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Sample records for detecting schistosomal antigens

  1. Molecular Detection of Schistosome Infections with a Disposable Microfluidic Cassette.

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    Jinzhao Song

    2015-12-01

    Full Text Available Parasitic helminths such as schistosomes, as well as filarial and soil-transmitted nematodes, are estimated to infect at least a billion people worldwide, with devastating impacts on human health and economic development. Diagnosis and monitoring of infection dynamics and efficacy of treatment depend almost entirely on methods that are inaccurate, labor-intensive, and unreliable. These shortcomings are amplified and take on added significance in mass drug administration programs, where measures of effectiveness depend on accurate monitoring of treatment success (or failure, changes in disease transmission rates, and emergence of possible drug resistance. Here, we adapt isothermal molecular assays such as loop-mediated isothermal amplification (LAMP to a simple, hand-held, custom-made field-ready microfluidic device that allows sensitive and specific detection of schistosome cell-free nucleic acids in serum and plasma (separated with a point-of-care plasma separator from Schistosoma mansoni-infected mice. Cell-free S. mansoni DNA was detected with our device without prior extraction from blood. Our chip exhibits high sensitivity (~2 x 10(-17 g/μL, with a positive signal for S. mansoni DNA detectable as early as one week post infection, several weeks before parasite egg production commences. These results indicate that incorporation of isothermal amplification strategies with our chips could represent a strategy for rapid, simple, low-cost diagnosis of both pre-patent and chronic schistosome infections as well as potential monitoring of treatment efficacy.

  2. Effect of praziquantel treatment during pregnancy on cytokine responses to schistosome antigens

    DEFF Research Database (Denmark)

    Tweyongyere, Robert; Mawa, Patrice A.; Ngom-Wegi, Sophy

    2008-01-01

    . Cytokine responses to S. mansoni worm and egg antigens were measured in whole blood culture before and 6 weeks after each treatment. RESULTS: Schistosome-specific cytokine responses were suppressed during pregnancy. Praziquantel treatment during pregnancy caused significant boosts in interferon-gamma (IFN......Praziquantel treatment of schistosomiasis boosts antischistosome responses, with type 2 helper T cell bias that may contribute to immunologically mediated killing and to protection against reinfection. Praziquantel treatment during pregnancy was recommended in 2002, but the immunological effects...... of the treatment had not been investigated. METHODS: A cohort of 387 Schistosoma mansoni-infected women were recruited from a larger trial of deworming during pregnancy. Women were randomized to receive either praziquantel or placebo during pregnancy. Six weeks after delivery, all women received praziquantel...

  3. Cytokine responses to the anti-schistosome vaccine candidate antigen glutathione-S-transferase vary with host age and are boosted by praziquantel treatment.

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    Claire D Bourke

    2014-05-01

    Full Text Available Improved helminth control is required to alleviate the global burden of schistosomiasis and schistosome-associated pathologies. Current control efforts rely on the anti-helminthic drug praziquantel (PZQ, which enhances immune responses to crude schistosome antigens but does not prevent re-infection. An anti-schistosome vaccine based on Schistosoma haematobium glutathione-S-transferase (GST is currently in Phase III clinical trials, but little is known about the immune responses directed against this antigen in humans naturally exposed to schistosomes or how these responses change following PZQ treatment.Blood samples from inhabitants of a Schistosoma haematobium-endemic area were incubated for 48 hours with or without GST before (n = 195 and six weeks after PZQ treatment (n = 107. Concentrations of cytokines associated with innate inflammatory (TNFα, IL-6, IL-8, type 1 (Th1; IFNγ, IL-2, IL-12p70, type 2 (IL-4, IL-5, IL-13, type 17 (IL-17A, IL-21, IL-23p19 and regulatory (IL-10 responses were quantified in culture supernatants via enzyme-linked immunosorbent assay (ELISA. Factor analysis and multidimensional scaling were used to analyse multiple cytokines simultaneously.A combination of GST-specific type 2 (IL-5 and IL-13 and regulatory (IL-10 cytokines was significantly lower in 10-12 year olds, the age group at which S. haematobium infection intensity and prevalence peak, than in 4-9 or 13+ year olds. Following PZQ treatment there was an increase in the number of participants producing detectable levels of GST-specific cytokines (TNFα, IL-6, IL-8, IFNγ, IL-12p70, IL-13 and IL-23p19 and also a shift in the GST-specific cytokine response towards a more pro-inflammatory phenotype than that observed before treatment. Participant age and pre-treatment infection status significantly influenced post-treatment cytokine profiles.In areas where schistosomiasis is endemic host age, schistosome infection status and PZQ treatment affect the

  4. Indian Schistosomes: A Need for Further Investigations

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    M. C. Agrawal

    2011-01-01

    Full Text Available India is uniquely positioned with regard to schistosomes and schistosomiasis—discovering seven new mammalian species with the existence of three more schistosome species: Orientobilharzia turkestanicum, O. harinasutai, and Schistosoma haematobium(?. An endemic focus of urinary schistosomiasis was reported from Gimvi village of Ratnagiri, Maharashtra with infrequent occurrence of schistosome eggs in human stools. Cercarial dermatitis has been reported to be more abundant in rural population using ponds, tanks, and so forth, for their domestic purposes. Few dermatitis cases were tested positive by CHR. Schistosome antigen was also detected in urine of five cases suggesting existence of active schistosomiasis in India. Nevertheless, human kind does not appear to be the usual host for Indian schistosomes in contrast to S. haematobium, S. mansoni, or S. japonicum. Various reasons for this phenomenon are discussed including evolution of Indian schistosomes, immune mechanisms, and environmental conditions. These and other aspects such as seasonal effect on the prevalence, snail infectivity, heterologous mating, existence of hybrids, and number of schistosomes in heterologous infections need further investigations with application of molecular techniques. Joint efforts by the national as well as international scientific community would be much more rewarding for better understanding of the parasite and the infection.

  5. Schistosome circulating anodic antigen in serum of individuals infected with Schistosoma japonicum from the Philippines before and after chemotherapy with praziquantel

    NARCIS (Netherlands)

    van 't Wout, A. B.; de Jonge, N.; Tiu, W. U.; Garcia, E. E.; Mitchell, G. F.; Deelder, A. M.

    1992-01-01

    The presence of the schistosome circulating anodic antigen (CAA) in serum of patients infected with Schistosoma japonicum from The Philippines has been investigated using an enzyme-linked immunosorbent assay (ELISA). Serum samples were tested from 48 patients who excreted S. japonicum eggs, 9

  6. [Effect of Parasep® feces centrifuge tube method on detecting schistosome eggs].

    Science.gov (United States)

    Ma, Nian; Zhang, Hua-ming; Liu, Xiong; Xiao, Chuan-yun; Wen, Xiao-hong; Li, Xia; Dong, Li-chun; Cui, Cai-xia; Tu, Zu-wu

    2014-08-01

    To evaluate the effect of the Parasep® feces centrifuge tube method on detecting schistosome eggs. A total of 803 residents aged from 6-65 years were selected in 2 schistosomiasis endemic villages, Jiangling County, Hubei Province, and their stool samples were collected and detected parallelly by the Kato-Katz technique, nylon silk egg hatching method, and Parasep® feces centrifuge tube method at the same time. Among the 803 people, 15 cases were found of schistosome egg positive, and the positive rate was 1.87%. The positive rates of the Kato-Katz technique, nylon silk egg hatching method, and Parasep® feces centrifuge tube method were 0.75%, 1.49% and 1.12%, respectively. The schistosome eggs got with the Parasep® feces centrifuge tube method were clear and easy to identify. In low endemic areas of schistosomiasis, the Parasep® feces centrifuge tube method can be used as schistosomiasis japonica etiology diagnosis method.

  7. Development of a Schistosoma mansoni shotgun O-glycan microarray and application to the discovery of new antigenic schistosome glycan motifs.

    Science.gov (United States)

    van Diepen, Angela; van der Plas, Arend-Jan; Kozak, Radoslaw P; Royle, Louise; Dunne, David W; Hokke, Cornelis H

    2015-06-01

    Upon infection with Schistosoma, antibody responses are mounted that are largely directed against glycans. Over the last few years significant progress has been made in characterising the antigenic properties of N-glycans of Schistosoma mansoni. Despite also being abundantly expressed by schistosomes, much less is understood about O-glycans and antibody responses to these have not yet been systematically analysed. Antibody binding to schistosome glycans can be analysed efficiently and quantitatively using glycan microarrays, but O-glycan array construction and exploration is lagging behind because no universal O-glycanase is available, and release of O-glycans has been dependent on chemical methods. Recently, a modified hydrazinolysis method has been developed that allows the release of O-glycans with free reducing termini and limited degradation, and we applied this method to obtain O-glycans from different S. mansoni life stages. Two-dimensional HPLC separation of 2-aminobenzoic acid-labelled O-glycans generated 362 O-glycan-containing fractions that were printed on an epoxide-modified glass slide, thereby generating the first shotgun O-glycan microarray containing naturally occurring schistosome O-glycans. Monoclonal antibodies and mass spectrometry showed that the O-glycan microarray contains well-known antigenic glycan motifs as well as numerous other, potentially novel, antibody targets. Incubations of the microarrays with sera from Schistosoma-infected humans showed substantial antibody responses to O-glycans in addition to those observed to the previously investigated N- and glycosphingolipid glycans. This underlines the importance of the inclusion of these often schistosome-specific O-glycans in glycan antigen studies and indicates that O-glycans contain novel antigenic motifs that have potential for use in diagnostic methods and studies aiming at the discovery of vaccine targets. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights

  8. Antigen detection systems

    Science.gov (United States)

    Infectious agents or their constituent parts (antigens or nucleic acids) can be detected in fresh, frozen, or fixed tissues or other specimens, using a variety of direct or indirect assays. The assays can be modified to yield the greatest sensitivity and specificity but in most cases a particular m...

  9. Murine eosinophils labeled with indium-111 oxine: localization to delayed hypersensitivity reactions against a schistosomal antigen and to lymphokine in vivo

    International Nuclear Information System (INIS)

    Rand, T.H.; Clanton, J.A.; Runge, V.; English, D.; Colley, D.G.

    1983-01-01

    We have evaluated a method for quantitation of eosinophil migration to stimuli in vivo. Upon transfusion into normal syngeneic mice, 111In-labeled eosinophils had an intravascular half-life of 9.5 hr and distributed predominantly into spleen, bone marrow, and liver. In either Schistosoma mansoni-infected mice or recipients of lymphoid cells from infected mice, intradermal (ear pinna) injection of the schistosomal egg antigenic preparation (SEA) elicited time-dependent accumulation of 111In-labeled eosinophils detectable by either gamma scintillation counting of tissue samples or by nuclear medicine external imaging. Intradermal administration of a lymphokine fraction (containing eosinophil stimulation promoter activity) similarly caused accumulation of 111In-labeled eosinophils. Both reactions depended on the concentration of stimulus (SEA or lymphokine). 111In-labeled neutrophils or macrophages or 125I-albumin did not preferentially accumulate at the reactions examined to the extent found with 111In-labeled eosinophils, indicating that localization of label depends on an active process and is due to eosinophils rather than a contaminating cell type. The method was used to estimate how long eosinotactic lymphokine remained at dermal sites: 60% of initial activity was present 12 hr after injection. The model is discussed with regard to the role of lymphokines in hypersensitivity reactions with eosinophil involvement, such as the granulomatous response to S. mansoni eggs

  10. [Demand for and the Development of Detection Techniques for Source of Schistosome Infection in China].

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    Wang, Shi-ping; He, Xin; Zhou, Yun-fei

    2015-12-01

    Schistosomiasis is a type of zoonotic parasitosis that severely impairs human health. Rapid detection of infection sources is a key to the control of schistosomiasis. With the effective control of schistosomiasis in China, the detection techniques for infection sources have also been developed. The rate and the intensity of infection among humans and livestocks have been significantly decreased in China, as the control program has entered the transmission control stage in most of the endemic areas. Under this situation, the traditional etiological diagnosing techniques and common immunological methods can not afford rapid detection of infection sources of schistosomiasis. Instead, we are calling for detection methods with higher sensitivity, specificity and stability while being less time-consuming, more convenient and less costing. In recent years, many improved or novel detection methods have been applied for the epidemiological surveillance of schistosomiasis, such as the automatic scanning microscopic image acquisition system, PCR-ELISA, immunosensors, loop-mediated isothermal amplification, etc. The development of new monitoring techniques can facilitate rapid detection of schistosome infection sources in endemic areas.

  11. Melatonin and schistosomal antigens ameliorate the anti-oxidative and biochemical response to Schistosoma mansoni infection in hamster

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    Omema SALAH

    2009-04-01

    Full Text Available The present study was designed to investigate the potential protective effect of melatonin as an antioxidant separately or in combination with antigens (cercarial; CAP or soluble worm; SWAP against Schistosoma mansoni infection in hamsters. Each hamster was sensitized with an initial immunization of 0.6 ml of the extracted antigen (30 μg protein/mL. After four days, a second injection of 0.4 mL was given (20 μg protein/mL. Then, each hamster was exposed to 260 ± 20 S.mansoni cercariae followed with melatonin treatment (3.5 mg/kg for thirty days from the 1st day of post infection. Levels of lipid peroxidation (LPO products, catalase (CAT activity, hepatic glutathione (GSH and biochemical changes in the liver and kidneys functions were investigated. The results revealed a high significant increasing of LPO and decreasing of CAT and GSH in liver of infected hamsters. Biochemical observations showed severe damage in the liver enzyme activities and increasing cholesterol level in infected animals. Melatonin co-treatment with antigen to the infected-hamster attenuated the increase of LPO and restored the activity of CAT and levels of hepatic GSH. Also, the biochemical damages in the liver and kidneys functions were reduced. The present study suggests that melatonin may be useful in combating free radical-induced damage due to infection toxicity. The immunization with previous antigens resulted in a remarkable improvement on the liver enzyme activities, which were increased after infection. Thus, vaccination of hamsters with antigens (both CAP and SWAP and melatonin treatment has more potent effect on the enhancement of antioxidant and biochemical of S. mansoni infected-hamster than each treatment separately. Immunization of the hamster with SWAP followed by melatonin was the best way among the other regime treatments to improve the biochemical and antioxidant parameters of the infected-hamsters

  12. Schistosomal glomerular disease (a review

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    Zilton A. Andrade

    1984-12-01

    Full Text Available In this review paper schistosomal glomerulopathy is defined as an immune-complex disease. The disease appears in 12-15 per cent of the individuals with hepatosplenic schistosomiasis. Portal hypertension with collateral circulation helps the by pass of the hepatic clearance process and the parasite antigens can bind to antibodies in the circulation and be trapped in the renal glomerulus. Chronic membranousproliferative glomerulonephritis is the most commom lesion present and the nephrotic syndrome is the usual form of clinical presentation. The disease can be experimentally produced, and schistosomal antigens and antibodies, as well as complement, can be demonstrated in the glomerular lesions. Specific treatment of schistosomiasis does not seem to alter the clinical course of schistosomal nephropathy.A glomerulopatia esquistossomotica e um exemplo de doenca causada por complexos imunes. Ela se manifesta em 12 a 15% dos portadores de forma hepato-eplenica da esquistossomose. A hipertensao porta, com circulacao colateral, facilita a ultrapassagem do filtro hepatico e os antigenos esquistossomoticos podem se acoplar aos anticorpos na circulacao e vir a se depositar nos glomerulos. O tipo histologico mais frequente e a glomerulonefrite cronica membrano-proliferativa, geralmente com sindrome nefrotica. A doenca e passivel de reproducao experimental e os antigenos esquistossomoticos, os anticorpos e fracoes do complemento podem ser demonstrados nas lesoes glomerulares. O tratamento especifico da esquistossomose nao mostrou ate o momento a capacidade de alterar o curso da nefropatia.

  13. Cell cultures for schistosomes - Chances of success or wishful thinking?

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    Quack, T; Wippersteg, V; Grevelding, C G

    2010-08-01

    Due to their worldwide importance for human and animal health, schistosomes are in the focus of national and international research activities. Their aims are to elucidate the genome, the transcriptome, the proteome and the glycome of schistosomes with the expectation to understand the biology of these blood flukes and to identify new candidate antigens for the development of a vaccine, or target molecules for the design of novel pharmaceutical compounds. All of these efforts have delivered a vast amount of information about the genetic equipment of schistosomes. In the emerging era of post-genomic research, however, methods and tools are necessary to interpret all available data and to characterise molecules of interest in more detail. In addition to transgenesis, it is generally accepted that cell lines for schistosomes are among the requirements to overcome present research limitations. In our commentary the prospect of establishing cell cultures for schistosomes is discussed. To this end we summarise the comprehensive endeavours made in the past regarding the establishment of invertebrate cell lines pointing to critical parameters that should be considered when making new attempts towards schistosome cell culturing. Furthermore, based on preliminary data with pilot-character, we discuss recent advances indicating the possibility of overcoming existing restrictions with respect to the 'immortalisation' of cells by oncogenes. Copyright 2010 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

  14. Evaluating the use of dedicated swab for rapid antigen detection ...

    African Journals Online (AJOL)

    Evaluating the use of dedicated swab for rapid antigen detection testing in group a ... African Journal of Clinical and Experimental Microbiology ... Several generations of rapid antigen detection tests (RADTs) have been developed to facilitate ...

  15. Nuclear techniques in schistosomiasis: Towards a schistosome vaccine

    International Nuclear Information System (INIS)

    Taylor, D.W.

    1986-01-01

    The paper reviews recent advances in schistosome research achieved through the application of nuclear techniques and aimed at the development of a vaccine. Two principal areas are discussed: first, immune effector mechanisms; and secondly, the application of hybridoma and recombinant DNA technology to the problem of production of large quantities of parasite antigens suitable for inclusion in an experimental vaccine. (author)

  16. Effect of praziquantel treatment of Schistosoma mansoni during pregnancy on intensity of infection and antibody responses to schistosome antigens

    DEFF Research Database (Denmark)

    Tweyongyere, Robert; Mawa, Patrice A.; Emojong, Nicholas O.

    2009-01-01

    with those first treated after delivery (undetected (88.5%), light (10.6%), moderate (0.9%) and heavy (0%), p = 0.16). Parasite specific antibody levels were lower during pregnancy than after delivery. Praziquantel treatment during pregnancy boosted anti-worm IgG isotypes and to a lesser extent Ig......E, but these boosts were less pronounced than in women whose treatment was delayed until after delivery. Praziquantel had limited effects on antibodies against egg antigens. Conclusion S mansoni antigen-specific antibody levels and praziquantel-induced boosts in antibody levels were broadly suppressed during...

  17. Prostatic specific antigen for prostate cancer detection

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    Lucas Nogueira

    2009-10-01

    Full Text Available Prostate-specific antigen (PSA has been used for prostate cancer detection since 1994. PSA testing has revolutionized our ability to diagnose, treat, and follow-up patients. In the last two decades, PSA screening has led to a substantial increase in the incidence of prostate cancer (PC. This increased detection caused the incidence of advanced-stage disease to decrease at a dramatic rate, and most newly diagnosed PC today are localized tumors with a high probability of cure. PSA screening is associated with a 75% reduction in the proportion of men who now present with metastatic disease and a 32.5% reduction in the age-adjusted prostate cancer mortality rate through 2003. Although PSA is not a perfect marker, PSA testing has limited specificity for prostate cancer detection, and its appropriate clinical application remains a topic of debate. Due to its widespread use and increased over-detection, the result has been the occurrence of over-treatment of indolent cancers. Accordingly, several variations as regards PSA measurement have emerged as useful adjuncts for prostate cancer screening. These procedures take into consideration additional factors, such as the proportion of different PSA isoforms (free PSA, complexed PSA, pro-PSA and B PSA, the prostate volume (PSA density, and the rate of change in PSA levels over time (PSA velocity or PSA doubling time. The history and evidence underlying each of these parameters are reviewed in the following article.

  18. Prostatic specific antigen for prostate cancer detection.

    Science.gov (United States)

    Nogueira, Lucas; Corradi, Renato; Eastham, James A

    2009-01-01

    Prostate-specific antigen (PSA) has been used for prostate cancer detection since 1994. PSA testing has revolutionized our ability to diagnose, treat, and follow-up patients. In the last two decades, PSA screening has led to a substantial increase in the incidence of prostate cancer (PC). This increased detection caused the incidence of advanced-stage disease to decrease at a dramatic rate, and most newly diagnosed PC today are localized tumors with a high probability of cure. PSA screening is associated with a 75% reduction in the proportion of men who now present with metastatic disease and a 32.5% reduction in the age-adjusted prostate cancer mortality rate through 2003. Although PSA is not a perfect marker, PSA testing has limited specificity for prostate cancer detection, and its appropriate clinical application remains a topic of debate. Due to its widespread use and increased over-detection, the result has been the occurrence of over-treatment of indolent cancers. Accordingly, several variations as regards PSA measurement have emerged as useful adjuncts for prostate cancer screening. These procedures take into consideration additional factors, such as the proportion of different PSA isoforms (free PSA, complexed PSA, pro-PSA and B PSA), the prostate volume (PSA density), and the rate of change in PSA levels over time (PSA velocity or PSA doubling time). The history and evidence underlying each of these parameters are reviewed in the following article.

  19. Polyclonal antibodies for the detection of Trypanosoma cruzi circulating antigens.

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    Edith S Málaga-Machaca

    2017-11-01

    Full Text Available Detection of Trypanosoma cruzi antigens in clinical samples is considered an important diagnostic tool for Chagas disease. The production and use of polyclonal antibodies may contribute to an increase in the sensitivity of immunodiagnosis of Chagas disease.Polyclonal antibodies were raised in alpacas, rabbits, and hens immunized with trypomastigote excreted-secreted antigen, membrane proteins, trypomastigote lysate antigen and recombinant 1F8 to produce polyclonal antibodies. Western blot analysis was performed to determine specificity of the developed antibodies. An antigen capture ELISA of circulating antigens in serum, plasma and urine samples was developed using IgY polyclonal antibodies against T. cruzi membrane antigens (capture antibody and IgG from alpaca raised against TESA. A total of 33 serum, 23 plasma and 9 urine samples were analyzed using the developed test. Among serum samples, compared to serology, the antigen capture ELISA tested positive in 55% of samples. All plasma samples from serology positive subjects were positive in the antigen capture ELISA. All urine positive samples had corresponding plasma samples that were also positive when tested by the antigen capture ELISA.Polyclonal antibodies are useful for detection of circulating antigens in both the plasma and urine of infected individuals. Detection of antigens is direct evidence of the presence of the parasite, and could be a better surrogate of current infection status.

  20. Detection of Rabies antigen in brains of suspected Rabid dogs ...

    African Journals Online (AJOL)

    Objective: To detect the presence of rabies antigen in brains of suspected rabid dogs. Materials and Methods: Ninety six (96) brain specimens from suspected rabid dogs were examined for the presence of rabies antigen using Seller's staining technique and enzyme immunoassay. Results: The two techniques were both ...

  1. Radioimmunoassay for the detection of Australia-SH antigen

    Energy Technology Data Exchange (ETDEWEB)

    Gerhardt, H [Giessen Univ. (Germany, F.R.). Zentrum fuer Innere Medizin

    1974-06-01

    Among infectious diseases, hepatitis presents a great problem in all countries with a high medical standard. The number of Australia antigen-positive cases rises from year to year, due to the increase in drug-fixer hepatitis and blood transfusions. Highly sensitive and at the same time practicable methods are therefore required for the identification of Australia antigen carriers and their elimination as blood donors. The most sensitive of all currently used tests for the detection of Australia antigen is the 'solid phase' radioimmunoassay since it permits an objective and quantitative measurement of the antigen.

  2. Detection of gonococcal antigens in urine by radioimmunoassay

    International Nuclear Information System (INIS)

    Thornley, M.J.; Wilson, D.V.; Hormaeche, R.D. de; Coombs, R.R.A.; Oates, J.K.

    1979-01-01

    A method of detecting gonococcal antigens by solid-phase radioimmunoassay with radioactively labelled antibody is described. A specificity test has been developed that enables this method to be used to detect gonococcal antigens in urine sediments. When sediments from samples of urine from male patients with gonorrhoea were tested, 31 (74%) of 42 gave positive results, clearly distinguishing them from sediments from urine samples from men with non-specific urethritis, none of which was positive. Ten of 14 urine sediments from urine samples from women with gonorrhoea gave positive results, as did 3 of 18 sediments from urine samples from women patients without gonorrhoea.These experiments demonstrate that gonococcal antigens can be detected in urine by radioimmunoassay; the method could be useful in diagnosis if, after refinement, its sensitivity and specificity were to be increased. (author)

  3. Acute Perforated Schistosomal Appendicitis: A Case Report ...

    African Journals Online (AJOL)

    Appendicitis is occasionally the first clinical manifestation of schistosomal infestation which may require treatment. A rare case of perforated schistosomal appendicitis in a 12 –year old Nigerian boy diagnosed on the basis of histological evaluation of the appendectomy specimen is reported to highlight the clinical ...

  4. [The clinical value of urinary antigen detection of Legionella pneumonia].

    Science.gov (United States)

    Jiang, Luxi; Chen, Yu; Xia, Shuyue; Ma, Jiangwei; Zhao, Hongwen; Lu, Ye; Tao, Sixu; Zhao, Li

    2015-01-01

    To investigate the clinical value of urinary antigen detection of Legionella, and to describe the clinical characteristics of Legionella pneumonia. Patients with suspected Legionella pneumonia were enrolled from the Respiratory departments of 3 tertiary hospitals in Shenyang during May 2011 to November 2013. Urinary Legionella antigen was detected for all the enrolled patients. Bacterial culture, polymerase chain reaction (PCR) for Legionella, and double Legionella antibody detection in sera were performed for each patient whose urinary antigen was positive. Patients confirmed to have Legionella pneumonia were pooled and analyzed. Totally 13 cases presenting with pneumonia were positive for Legionella by the urinary antigen method, and in one of them Legionella strain was isolated from the secretion of lower respiratory tract. PCR detection was performed in 8 patients, and 4 of them were positive. Legionella antibody detection was performed in 12 patients, and 7 of them were positive. Nine patients had a history of exposure to Legionella high-risk environments. The characteristics of the cases with Legionella pneumonia were as follows: characteristic orange sputum in 4 patients, digestive symptoms in 6, neurologic disorders in 8, hyponatremia in 10, hypoxia with oxygenation index 130) in 8 patients . Chest CT scan showed bilateral involvement in 6, ground-glass opacity combined with consolidation in 11, and moderate pleural effusion in 11 patients. Cavity and reversed halo sign were found in one case, respectively. All of the patients received fluoroquinolone treatment, and 11 patients recovered completely while 2 died of multiple organ dysfunction syndrome, one of them was complicated with secondary infection. Detection of urinary antigen of Legionella is very useful in the diagnosis of Legionella pneumonia. Attention should be paid to exposure history to the high-risk environments and multiple organ impairment when Legionella infection is suspected. Orange sputum

  5. Detection of Rabies Antigen in the Brain Tissues of Apparetly ...

    African Journals Online (AJOL)

    Rabies is a serious public health hazard and recently outbreaks of the disease have been reported in three local government areas in Cross River State. Detection of rabies antigen in the brain tissues of apparently healthy dogs indicates the presence of rabies virus and this is a significant factor in the transmission and ...

  6. Potential radioimmunoassay system for detection of Hanganutziu-Deicher type heterophile antigen(s) and antibodies in tissues and fluids

    Energy Technology Data Exchange (ETDEWEB)

    Mukuria, J C; Naiki, Masaharu; Hashimoto, Masato; Nishiura, Katsumi; Okabe, Masahiro; Kato, Shiro

    1985-06-12

    A relatively simple, specific and sensitive radioimmunoassay system has been developed for the detection of heterophile Hanganutziu-Deicher (H-D) antigen(s) and antibodies. The SVI-labeled H-D antigen-active molecule used for the assay is a bovine erythrocyte major glycoprotein previously found to have a strong H-D antigen potency. Different H-D antigen-active molecules were compared for heterophile H-D antigen potency. Eight different lung cancer tissues were assayed for H-D antigen. The sera from the 8 lung cancer patients were also screened by ELISA and RIA in an attmept to correlate expression of H-D antigen on tissues with elevation of H-D antibodies.

  7. Avian Schistosomes and Outbreaks of Cercarial Dermatitis

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    Mikeš, Libor; Lichtenbergová, Lucie; Skála, Vladimír; Soldánová, Miroslava; Brant, Sara Vanessa

    2015-01-01

    SUMMARY Cercarial dermatitis (swimmer's itch) is a condition caused by infective larvae (cercariae) of a species-rich group of mammalian and avian schistosomes. Over the last decade, it has been reported in areas that previously had few or no cases of dermatitis and is thus considered an emerging disease. It is obvious that avian schistosomes are responsible for the majority of reported dermatitis outbreaks around the world, and thus they are the primary focus of this review. Although they infect humans, they do not mature and usually die in the skin. Experimental infections of avian schistosomes in mice show that in previously exposed hosts, there is a strong skin immune reaction that kills the schistosome. However, penetration of larvae into naive mice can result in temporary migration from the skin. This is of particular interest because the worms are able to migrate to different organs, for example, the lungs in the case of visceral schistosomes and the central nervous system in the case of nasal schistosomes. The risk of such migration and accompanying disorders needs to be clarified for humans and animals of interest (e.g., dogs). Herein we compiled the most comprehensive review of the diversity, immunology, and epidemiology of avian schistosomes causing cercarial dermatitis. PMID:25567226

  8. Morphological Specifications of the Bird Schistosome Cercariae and Surface Carbohydrates as Receptors for Lectins

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    I Moebedi

    2007-04-01

    Full Text Available Background: To determine the morphological specifications of the bird schistosomes cercaria from Lymnaea gedrosiana and to detect the surface carbohydrates as receptors for host lectins in the host-parasite relationship systems such as avian schistosomiasis and human cercarial dermatitis. Methods: One hundred ninety two snails collected from Dezful areas in Khuzestan Province, in the south west of Iran, during 2005-2006 were examined for cercariae using shedding and crushing methods. In addition, surface carbohydrates on the cercariae were detected by lentil (Lens culinaris lectins. Results: From the total number of Lymnaea gedrosiana, which examined for bird schistosomes cercaria, 9(4% snails were found to be infected with furcocercus cercaria of the bird schistosomes (probably Gigantobilharzia sp.. Mannose monosaccharide CH2OH (CHOH4CHO as surface carbohydrate was also detected on the cercariae. Conclusion: Mannose carbohydrate on these cercariae may be used as receptor by lectins.

  9. Antigen spot test (AST): a highly sensitive assay for the detection of antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Herbrink, P; van Bussel, F J; Warnaar, S O [Rijksuniversiteit Leiden (Netherlands)

    1982-02-12

    A method is described for detection of antibodies by means of nitrocellulose or diazobenzyloxymethyl (DBM) paper on which various antigens have been spotted. The sensitivity of this antigen spot test (AST) is comparable with that of RIA and ELISA. The method requires only nanogram amounts of antigen. Since a variety of antigens can be spotted on a single piece of nitrocellulose or DBM paper, this antigen spot test is especially useful for specificity controls on antibodies.

  10. Interplay between CKS2, N-cadherin, and PD-ECGF in Non-Schistosomal and Schistosomal-Associated Bladder Cancer: A Prospective Comparative Study in the Egyptian Population

    Directory of Open Access Journals (Sweden)

    Sanaa Shawky

    2017-01-01

    Full Text Available Background: The current study investigated the possible role of the cell cycle regulator, cyclin-dependent kinases regulatory subunit-2; the angiogenic factor, plateletderived endothelial cell growth factor; and the cell adhesive molecule, neural cadherin, as prognostic factors in schistosomal and non-schistosomal-associated urothelial carcinomas. We also investigated the possible correlation between cyclin-dependent kinases regulatory subunit-2, platelet-derived endothelial cell growth factor, neural cadherin, tumor grade, and stage. Methods: The study included 40 patients with primary bladder cancer (25 nonschistosomal- associated and 15 schistosomal-associated who had no prior anticancer treatment. Tumor specimens were collected at the time of the transurethral resection. The vivid portions of the resected tumors were subjected to routine pathological examinations to determine stage, grade, and schistosomal infestation. Control bladder tissues (5 cases were obtained by cystoscopic biopsies from patients who underwent transurethral resection of the prostate. Platelet-derived endothelial cell growth factor and neural cadherin protein expressions were evaluated by immunohistochemical staining. RNA was extracted, reverse transcribed, and amplified by PCR using cyclindependent kinases regulatory subunit-2 specific primers. Relative expression was detected by a comparison of the expression in normal and tumor samples relative to GAPDH (housekeeping gene expression. Results:We detected a positive correlation between neural cadherin and plateletderived endothelial cell growth factor proteins in schistosomal-associated and non-schistosomal-associated bladder cancer. Significant overexpression of relative cyclin-dependent kinases regulatory subunit-2 gene, neural cadherin, and plateletderived endothelial cell growth factor proteins were detected in invasive stages and higher grades of bladder cancer. Differential expressions of neural cadherin and

  11. Immunoliposome-PCR: a generic ultrasensitive quantitative antigen detection system

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    He Junkun

    2012-06-01

    Full Text Available Abstract Background The accurate quantification of antigens at low concentrations over a wide dynamic range is needed for identifying biomarkers associated with disease and detecting protein interactions in high-throughput microarrays used in proteomics. Here we report the development of an ultrasensitive quantitative assay format called immunoliposome polymerase chain reaction (ILPCR that fulfills these requirements. This method uses a liposome, with reporter DNA encapsulated inside and biotin-labeled polyethylene glycol (PEG phospholipid conjugates incorporated into the outer surface of the liposome, as a detection reagent. The antigenic target is immobilized in the well of a microplate by a capture antibody and the liposome detection reagent is then coupled to a biotin-labeled second antibody through a NeutrAvidin bridge. The liposome is ruptured to release the reporter DNA, which serves as a surrogate to quantify the protein target using real-time PCR. Results A liposome detection reagent was prepared, which consisted of a population of liposomes ~120 nm in diameter with each liposome possessing ~800 accessible biotin receptors and ~220 encapsulated reporters. This liposome detection reagent was used in an assay to quantify the concentration of carcinoembryonic antigen (CEA in human serum. This ILPCR assay exhibited a linear dose–response curve from 10-10 M to 10-16 M CEA. Within this range the assay coefficient of variance was Conclusions The ILPCR assay has several advantages over other immuno-PCR methods. The reporter DNA and biotin-labeled PEG phospholipids spontaneously incorporate into the liposomes as they form, simplifying preparation of the detection reagent. Encapsulation of the reporter inside the liposomes allows nonspecific DNA in the assay medium to be degraded with DNase I prior to quantification of the encapsulated reporter by PCR, which reduces false-positive results and improves quantitative accuracy. The ability to

  12. Real-time prostate-specific antigen detection with prostate-specific antigen imprinted capacitive biosensors

    Energy Technology Data Exchange (ETDEWEB)

    Ertürk, Gizem [Department of Biotechnology, Lund University, Lund (Sweden); Department of Biology, Hacettepe University, Ankara (Turkey); Hedström, Martin [Department of Biotechnology, Lund University, Lund (Sweden); CapSenze HB, Medicon Village, SE-223 63 Lund (Sweden); Tümer, M. Aşkın [Department of Biology, Hacettepe University, Ankara (Turkey); Denizli, Adil [Department of Chemistry, Hacettepe University, Ankara (Turkey); Mattiasson, Bo, E-mail: Bo.Mattiasson@biotek.lu.se [Department of Biotechnology, Lund University, Lund (Sweden); CapSenze HB, Medicon Village, SE-223 63 Lund (Sweden)

    2015-09-03

    Prostate specific antigen (PSA) is a valuable biomarker for early detection of prostate cancer, the third most common cancer in men. Ultrasensitive detection of PSA is crucial to screen the prostate cancer in an early stage and to detect the recurrence of the disease after treatment. In this report, microcontact-PSA imprinted (PSA-MIP) capacitive biosensor chip was developed for real-time, highly sensitive and selective detection of PSA. PSA-MIP electrodes were prepared in the presence of methacrylic acid (MAA) as the functional monomer and ethylene glycol dimethacrylate (EGDMA) as the cross-linker via UV polymerization. Immobilized Anti-PSA antibodies on electrodes (Anti-PSA) for capacitance measurements were also prepared to compare the detection performances of both methods. The electrodes were characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM) and cyclic voltammetry (CV) and real-time PSA detection was performed with standard PSA solutions in the concentration range of 10 fg mL{sup −1}–100 ng mL{sup −1}. The detection limits were found as 8.0 × 10{sup −5} ng mL{sup −1} (16 × 10{sup −17} M) and 6.0 × 10{sup −4} ng mL{sup −1} (12 × 10{sup −16} M) for PSA-MIP and Anti-PSA electrodes, respectively. Selectivity studies were performed against HSA and IgG and selectivity coefficients were calculated. PSA detection was also carried out from diluted human serum samples and finally, reproducibility of the electrodes was tested. The results are promising and show that when the sensitivity of the capacitive system is combined with the selectivity and reproducibility of the microcontact-imprinting procedure, the resulting system might be used successfully for real-time detection of various analytes even in very low concentrations. - Highlights: • Microcontact imprinting method was used for preparing the sensor chip for capacitive biosensing. • High sensitivity was obtained. • Good selectivity was

  13. Real-time prostate-specific antigen detection with prostate-specific antigen imprinted capacitive biosensors

    International Nuclear Information System (INIS)

    Ertürk, Gizem; Hedström, Martin; Tümer, M. Aşkın; Denizli, Adil; Mattiasson, Bo

    2015-01-01

    Prostate specific antigen (PSA) is a valuable biomarker for early detection of prostate cancer, the third most common cancer in men. Ultrasensitive detection of PSA is crucial to screen the prostate cancer in an early stage and to detect the recurrence of the disease after treatment. In this report, microcontact-PSA imprinted (PSA-MIP) capacitive biosensor chip was developed for real-time, highly sensitive and selective detection of PSA. PSA-MIP electrodes were prepared in the presence of methacrylic acid (MAA) as the functional monomer and ethylene glycol dimethacrylate (EGDMA) as the cross-linker via UV polymerization. Immobilized Anti-PSA antibodies on electrodes (Anti-PSA) for capacitance measurements were also prepared to compare the detection performances of both methods. The electrodes were characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM) and cyclic voltammetry (CV) and real-time PSA detection was performed with standard PSA solutions in the concentration range of 10 fg mL"−"1–100 ng mL"−"1. The detection limits were found as 8.0 × 10"−"5 ng mL"−"1 (16 × 10"−"1"7 M) and 6.0 × 10"−"4 ng mL"−"1 (12 × 10"−"1"6 M) for PSA-MIP and Anti-PSA electrodes, respectively. Selectivity studies were performed against HSA and IgG and selectivity coefficients were calculated. PSA detection was also carried out from diluted human serum samples and finally, reproducibility of the electrodes was tested. The results are promising and show that when the sensitivity of the capacitive system is combined with the selectivity and reproducibility of the microcontact-imprinting procedure, the resulting system might be used successfully for real-time detection of various analytes even in very low concentrations. - Highlights: • Microcontact imprinting method was used for preparing the sensor chip for capacitive biosensing. • High sensitivity was obtained. • Good selectivity was demonstrated. • Stability of

  14. DETECTION OF CANINE PARVOVIRUS ANTIGEN IN DOGS IN KUMASI, GHANA.

    Science.gov (United States)

    Folitse, R D; Kodie, D O; Amemor, E; Dei, D; Tasiame, W; Burimuah, V; Emikpe, B O

    2018-01-01

    Canine Parvovirus (CPV) in dogs has been documented in many countries. However, evidence of the infection is scanty in Ghana. This study was conducted to detect canine parvovirus antigen in dogs presented with diarrhoea to the Government Veterinary Clinic in Kumasi, Ghana. Faecal samples from 72 dogs presented with diarrhoea were tested for the presence of canine parvovirus antigen using commercially available rapid test kit (BIT ® Rapid Colour Canine Parvovirus Ag Test Kit, BIOINDIST Co. Ltd, Korea) based on the principle of immunochromatography. Influence of breed, sex, age, vaccination history and the nature of diarrhoea were assessed. Data obtained was analysed with SPSS and subjected to the chi-square test. Significance was at α 0.05 . We found 61.11% tested positive (44/72) for CPV. Based on sex, 61.54% of males (20/33) and 60.61% of females tested positive (24/39). A total of 65.67% of samples from puppies below 6 months were positive. 56.25% of CPV vaccinated dogs and 70.83% of unvaccinated dogs were positive respectively. 69.05% of samples from haemorrhagic diarrhoeic dogs and 50.00% from non-haemorrhagic diarrhoeic dogs were positive of CPV. The study is the first documented evidence of the existence of CPV in Ghana. It also revealed that absence of bloody diarrhoea does not necessarily rule out CPV infection.

  15. DETECTION OF CANINE PARVOVIRUS ANTIGEN IN DOGS IN KUMASI, GHANA

    Science.gov (United States)

    Folitse, R. D; Kodie, D.O; Amemor, E.; Dei, D.; Tasiame, W.; Burimuah, V.; Emikpe, B.O

    2018-01-01

    Background: Canine Parvovirus (CPV) in dogs has been documented in many countries. However, evidence of the infection is scanty in Ghana. This study was conducted to detect canine parvovirus antigen in dogs presented with diarrhoea to the Government Veterinary Clinic in Kumasi, Ghana. Materials and Methods: Faecal samples from 72 dogs presented with diarrhoea were tested for the presence of canine parvovirus antigen using commercially available rapid test kit (BIT® Rapid Colour Canine Parvovirus Ag Test Kit, BIOINDIST Co. Ltd, Korea) based on the principle of immunochromatography. Influence of breed, sex, age, vaccination history and the nature of diarrhoea were assessed. Data obtained was analysed with SPSS and subjected to the chi-square test. Significance was at α0.05 Results: We found 61.11% tested positive (44/72) for CPV. Based on sex, 61.54% of males (20/33) and 60.61% of females tested positive (24/39). A total of 65.67% of samples from puppies below 6 months were positive. 56.25% of CPV vaccinated dogs and 70.83% of unvaccinated dogs were positive respectively. 69.05% of samples from haemorrhagic diarrhoeic dogs and 50.00% from non-haemorrhagic diarrhoeic dogs were positive of CPV. Conclusion: The study is the first documented evidence of the existence of CPV in Ghana. It also revealed that absence of bloody diarrhoea does not necessarily rule out CPV infection. PMID:29302647

  16. SCHISTOSOMAL APPENDICITIS IN A SLIDING HERNIA (CASE ...

    African Journals Online (AJOL)

    We report a rare case of a forty-seven year old Nigeria male with schistosomal appendicitis in a sliding hernia. The clinical and pathological features of the case are discussed, followed by a review of the literature. It is concluded that a high index of suspicion is necessary to diagnose unusual presentations of ...

  17. Immunological Consequences of Antihelminthic Treatment in Preschool Children Exposed to Urogenital Schistosome Infection

    Directory of Open Access Journals (Sweden)

    Nadine Rujeni

    2013-01-01

    Full Text Available Urogenital schistosomiasis, due to Schistosoma haematobium, is endemic in sub-Saharan Africa. Control is by targeted treatment with praziquantel but preschool age children are excluded from control programs. Immunological studies on the effect of treatment at this young age are scarce. In light of studies in older individuals showing that praziquantel alters antischistosome immune responses and responses to bystander antigens, this study aims to investigate how these responses would be affected by treatment at this young age. Antibody responses directed against schistosome antigens, Plasmodium falciparum crude and recombinant antigens, and the allergen house dust mite were measured in children aged 3 to 5 years before and 6 weeks after treatment. The change in serological recognition of schistosome proteins was also investigated. Treatment augmented antischistosome IgM and IgE responses. The increase in IgE responses directed against adult worm antigens was accompanied by enhanced antigen recognition by sera from the children. Antibody responses directed against Plasmodium antigens were not significantly affected by praziquantel treatment nor were levels of allergen specific responses. Overall, praziquantel treatment enhanced, quantitatively and qualitatively, the antiworm responses associated with protective immunity but did not alter Plasmodium-specific responses or allergen-specific responses which mediate pathology in allergic disease.

  18. Detection of proliferating cell nuclear antigens and interleukin-2 beta receptor molecules on mitogen- and antigen-stimulated lymphocytes.

    Science.gov (United States)

    Hesketh, J; Dobbelaere, D; Griffin, J F; Buchan, G

    1993-01-01

    The expression of interleukin-2 receptors (IL-2R) and proliferating cell nuclear antigens (PCNA) were compared for their usefulness as markers of lymphocyte activation. Heterologous polyclonal (anti-bovine IL-2R) and monoclonal (anti-human PCNA) antibodies were used to detect the expression of these molecules on activated deer lymphocytes. Both molecules were co-expressed on blast cells which had been activated with mitogen [concanavalin A (Con A)]. There was detectable up-regulation of IL-2R expression in response to antigen [Mycobacterium bovis-derived purified protein derivative (PPD)] stimulation while PCNA expression mimicked lymphocyte transformation (LT) reactivity. PCNA expression was found to more accurately reflect both antigen- and mitogen-activated lymphocyte activation, as estimated by LT activity. The expression of PCNA was used to identify antigen reactive cells from animals exposed to M. bovis. A very low percentage (1.1 +/- 0.4%) of peripheral blood lymphocytes from non-infected animals could be stimulated to express PCNA by in vitro culture with antigen (PPD). Within the infected group both diseased and healthy, 'in-contact', animals expressed significantly higher levels of PCNA upon antigen stimulation. PMID:8104884

  19. Investigation of contactless detection using a giant magnetoresistance sensor for detecting prostate specific antigen.

    Science.gov (United States)

    Sun, Xuecheng; Zhi, Shaotao; Lei, Chong; Zhou, Yong

    2016-08-01

    This paper presents a contactless detection method for detecting prostate specific antigen with a giant magnetoresistance sensor. In contactless detection case, the prostate specific antigen sample preparation was separated from the sensor that prevented the sensor from being immersed in chemical solvents, and made the sensor implementing in immediately reuse without wash. Experimental results showed that applied an external magnetic field in a range of 50 Oe to 90 Oe, Dynabeads with a concentration as low as 0.1 μg/mL can be detected by this system and could give an approximate quantitation to the logarithmic of Dynabeads concentration. Sandwich immunoassay was employed for preparing PSA samples. The PSA capture was implemented on a gold film modified with a self-assembled monolayer and using biotinylated secondary antibody against PSA and streptavidinylated Dynabeads. With DC magnetic field in the range of 50 to 90 Oe, PSA can be detected with a detection limit as low as 0.1 ng/mL. Samples spiked with different concentrations of PSA can be distinguished clearly. Due to the contactless detection method, the detection system exhibited advantages such as convenient manipulation, reusable, inexpensive, small weight. So, this detection method was a promising candidate in biomarker detection, especially in point of care detection.

  20. Evaluation of schistosome promoter expression for transgenesis and genetic analysis.

    Directory of Open Access Journals (Sweden)

    Shuang Liang

    Full Text Available Schistosome worms of the genus Schistosoma are the causative agents of schistosomiasis, a devastating parasitic disease affecting more than 240 million people worldwide. Schistosomes have complex life cycles, and have been challenging to manipulate genetically due to the dearth of molecular tools. Although the use of gene overexpression, gene knockouts or knockdowns are straight-forward genetic tools applied in many model systems, gene misexpression and genetic manipulation of schistosome genes in vivo has been exceptionally challenging, and plasmid based transfection inducing gene expression is limited. We recently reported the use of polyethyleneimine (PEI as a simple and effective method for schistosome transfection and gene expression. Here, we use PEI-mediated schistosome plasmid transgenesis to define and compare gene expression profiles from endogenous and nonendogenous promoters in the schistosomula stage of schistosomes that are potentially useful to misexpress (underexpress or overexpress gene product levels. In addition, we overexpress schistosome genes in vivo using a strong promoter and show plasmid-based misregulation of genes in schistosomes, producing a clear and distinct phenotype--death. These data focus on the schistosomula stage, but they foreshadow strong potential for genetic characterization of schistosome molecular pathways, and potential for use in overexpression screens and drug resistance studies in schistosomes using plasmid-based gene expression.

  1. A Model System for Concurrent Detection of Antigen and Antibody Based on Immunological Fluorescent Method

    Directory of Open Access Journals (Sweden)

    Yuan-Cheng Cao

    2015-01-01

    Full Text Available This paper describes a combined antigen/antibody immunoassay implemented in a 96-well plate using fluorescent spectroscopic method. First, goat anti-human IgG was used to capture human IgG (model antigen; goat anti-human IgG (Cy3 or FITC was used to detect the model antigen; a saturating level of model antigen was then added followed by unlabelled goat anti-human IgG (model antibody; finally, Cy3 labelled rabbit anti-goat IgG was used to detect the model antibody. Two approaches were applied to the concomitant assay to analyze the feasibility. The first approach applied FITC and Cy3 when both targets were present at the same time, resulting in 50 ng/mL of the antibody detection limit and 10 ng/mL of antigen detection limit in the quantitative measurements of target concentration, taking the consideration of FRET efficiency of 68% between donor and acceptor. The sequential approach tended to lower the signal/noise (S/N ratio and the detection of the model antigen (lower than 1 ng/mL had better sensitivity than the model antibody (lower than 50 ng/mL. This combined antigen/antibody method might be useful for combined detection of antigens and antibodies. It will be helpful to screen for both antigen and antibody particularly in the situations of the multiserotype and high-frequency mutant virus infections.

  2. Simultaneous detection of Hepatitis B surface antigen and its antibody by radioimmunoassay

    International Nuclear Information System (INIS)

    Crouzat-Reynes, Gerard; Perigois, Francois; Lecureuil, Michel; Lejeune, Bernard

    1981-01-01

    The authors describe an original radioimmunoassay which allows the simultaneous detection of hepatitis B surface antigen and its antibody in a biological sample. Antigen and antibody are indiscriminately detected in a first step and then distinguished in a second step using the same reagents [fr

  3. RAPID DETECTION OF PNEUMOCOCCAL ANTIGEN IN PLEURAL FLUID OF PATIENTS WITH COMMUNITY ACQUIRED PNEUMONIA

    NARCIS (Netherlands)

    BOERSMA, WG; LOWENBERG, A; HOLLOWAY, Y; KUTTSCHRUTTER, H; SNIJDER, JAM; KOETER, GH

    Background Detection of pneumococcal antigen may help to increase the rate of diagnosis of pneumococcal pneumonia. This study was designed to determine the value of rapid detection of pneumococcal antigen in pleural fluid from patients with community acquired pneumonia. Methods Thoracentesis was

  4. Biological control of schistosome transmission in flowing water habitats.

    Science.gov (United States)

    Jobin, W R; Laracuente, A

    1979-09-01

    Marisa cornuarietis was evaluated in Puerto Rico for control of schistosome transmission in flowing water. A population of Biomphalaria glabrata and their schistosome infections disappeared after introduction of 20,000 M. cornuarietis to an endemic stream, while in nearby untreated streams the B. glabrata population remained stable and the schistosome prevalence increased. This method cost U.S. $0.10 per capita for over a year of protection, 5%-10% of the cost of chemical control.

  5. Detection of HCV core antigen and its diagnostic significance

    Directory of Open Access Journals (Sweden)

    YANG Jie

    2013-02-01

    Full Text Available ObjectiveTo compare the abilities of the hepatitis C virus (HCV core antigen (cAg test and the HCV RNA assay for confirming anti-HCV presence in order to determine the clinical utility of the HCV-cAg as an alternative or confirmatory diagnostic tool. MethodsSerum samples collected from 158 patients diagnosed with HCV infection were subjected to the enzyme-linked immunosorbent assay-based HCV-cAg test. The optical density (OD measured values were used to calculate the ratio of specimen absorbance to the cutoff value (S/CO. Simultaneously, the serum samples were subjected to PCR-based nucleic acid amplification quantitative fluorescence detection of HCV RNA. ResultsNone of the serum samples had a S/CO value <1 for the HCV-cAg test (100% negative, but all of the samples had a S/CO value >5 (100% positive. The HCV-cAg test sensitivity was 87.05%, specificity was 76.67%, positive predictive value was 9653%, and negative predictive value was 44.23%. As the S/CO value gradually increased, the significantly higher positive coincident rate of the HCV RNA test decreased. The HCV RNA negative coincident rate was significantly higher than that of the HCV-cAg test. HCV-cAg S/CO values between 1 and 2 corresponded to an HCV RNA values between 1.0×103 copies/ml and 1.0×104 copies/ml. The highest S/CO value obtained was 1.992. ConclusionThe HCV-cAg test is comparable to the HCV RNA assay for diagnosing HCV infection.

  6. Development of recombinant antigen array for simultaneous detection of viral antibodies.

    Directory of Open Access Journals (Sweden)

    Yi Liu

    Full Text Available Protein microarrays have been developed to study antibody reactivity against a large number of antigens, demonstrating extensive perspective for clinical application. We developed a viral antigen array by spotting four recombinant antigens and synthetic peptide, including glycoprotein G of herpes simplex virus (HSV type 1 and 2, phosphoprotein 150 of cytomegalovirus (CMV, Rubella virus (RV core plus glycoprotein E1 and E2 as well as a E1 peptide with the optimal concentrations on activated glass slides to simultaneously detect IgG and IgM against HSV1, HSV2, CMV and RV in clinical specimens of sera and cerebrospinal fluids (CSFs. The positive reference sera were initially used to measure the sensitivity and specificity of the array with the optimal conditions. Then clinical specimens of 144 sera and 93 CSFs were tested for IgG and IgM antibodies directed against HSV1, HSV2, CMV and RV by the antigen array. Specificity of the antigen array for viral antibodies detection was satisfying compared to commercial ELISA kits but sensitivity of the array varied relying on quality and antigenic epitopes of the spotting antigens. In short, the recombinant antigen array has potential to simultaneous detect multiple viral antibodies using minute amount (3 µl of samples, which holds the particularly advantage to detect viral antibodies in clinical CSFs being suspicious of neonatal meningitis and encephalitis.

  7. Fast and efficient detection of tuberculosis antigens using liposome encapsulated secretory proteins of Mycobacterium tuberculosis

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    Dileep Tiwari

    2017-04-01

    Conclusion: Our study demonstrated that the newly developed liposome tuberculosis antigen card test detected antigens in our study population with approximately 97.48% sensitivity and 95.79% specificity. This is the first study to report the liposomal encapsulation of culture filtrate proteins from M. tuberculosis for diagnostic application.

  8. DETECTION OF PNEUMOCOCCAL CAPSULAR ANTIGEN IN THE PRESENCE OF PENICILLIN IN-VITRO

    NARCIS (Netherlands)

    HOLLOWAY, Y; BOERSMA, WG; KUTTSCHRUTTER, H; SNIJDER, JAM

    1993-01-01

    Eight strains of Streptococcus pneumoniae were tested in vitro for their ability to produce capsular antigen in the presence of penicillin. It was found that, provided 10(6) to 10(7) pneumococci/ml were present, capsular antigen could be detected during the 72 h in which the experiment was

  9. Detection of Burkholderia pseudomallei O-antigen serotypes in near-neighbor species

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    Stone Joshua K

    2012-11-01

    Full Text Available Abstract Background Burkholderia pseudomallei is the etiological agent of melioidosis and a CDC category B select agent with no available effective vaccine. Previous immunizations in mice have utilized the lipopolysaccharide (LPS as a potential vaccine target because it is known as one of the most important antigenic epitopes in B. pseudomallei. Complicating this strategy are the four different B. pseudomallei LPS O-antigen types: A, B, B2, and rough. Sero-crossreactivity is common among O-antigens of Burkholderia species. Here, we identified the presence of multiple B. pseudomallei O-antigen types and sero-crossreactivity in its near-neighbor species. Results PCR screening of O-antigen biosynthesis genes, phenotypic characterization using SDS-PAGE, and immunoblot analysis showed that majority of B. mallei and B. thailandensis strains contained the typical O-antigen type A. In contrast, most of B. ubonensis and B. thailandensis-like strains expressed the atypical O-antigen types B and B2, respectively. Most B. oklahomensis strains expressed a distinct and non-seroreactive O-antigen type, except strain E0147 which expressed O-antigen type A. O-antigen type B2 was also detected in B. thailandensis 82172, B. ubonensis MSMB108, and Burkholderia sp. MSMB175. Interestingly, B. thailandensis-like MSMB43 contained a novel serotype B positive O-antigen. Conclusions This study expands the number of species which express B. pseudomallei O-antigen types. Further work is required to elucidate the full structures and how closely these are to the B. pseudomallei O-antigens, which will ultimately determine the efficacy of the near-neighbor B serotypes for vaccine development.

  10. Detection of HBs antigens and antibodies by immunoenzymology and radioimmunology. Comparison of the results

    International Nuclear Information System (INIS)

    Fauchet, R.; Genetet, B.; Phengsavath

    1981-01-01

    The respective sensitivity threshold of immunoenzymology and radioimmunology in HBs antigen and antibody detection were compared and the optical density (o.d.) and counts per minute (cpm) values were correlated with the concentration in ng/ml of a given sample. The sensitivity comparison between RIA and EIA appears in favour of the former technique for both HBs antigen and HBs antibody detection. However the procedure tried here to detect HBs antibodies by immunoenzymology is simple, requires only the choice of neutralising antigenic pool and sensitivity threshold and could usefully be generalized for teams not authorized to handle radioelements. Quantification of the HBs antigen content in ng/ml is a difficult operation, needing great care in the dilution of the sera tested. The reproducibility is not perfect. The semi-quantitative RIA determination expressed in R.U. (radioimmunological units) seems adequate as a mean to follow the progress of an HBs antibody in both liver disease and vaccination [fr

  11. Performance Assessment of Four Chimeric Trypanosoma cruzi Antigens Based on Antigen-Antibody Detection for Diagnosis of Chronic Chagas Disease.

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    Fred Luciano Neves Santos

    Full Text Available The performance of serologic tests in chronic Chagas disease diagnosis largely depends on the type and quality of the antigen preparations that are used for detection of anti-Trypanosoma cruzi antibodies. Whole-cell T. cruzi extracts or recombinant proteins have shown variation in the performance and cross-reactivity. Synthetic chimeric proteins comprising fragments of repetitive amino acids of several different proteins have been shown to improve assay performances to detect Chagasic infections. Here, we describe the production of four chimeric T. cruzi proteins and the assessment of their performance for diagnostic purposes. Circular Dichroism spectra indicated the absence of well-defined secondary structures, while polydispersity evaluated by Dynamic Light Scattering revealed only minor aggregates in 50 mM carbonate-bicarbonate (pH 9.6, demonstrating that it is an appropriate buffering system for sensitizing microplates. Serum samples from T. cruzi-infected and non-infected individuals were used to assess the performance of these antigens for detecting antibodies against T. cruzi, using both enzyme-linked immunosorbent assay and a liquid bead array platform. Performance parameters (AUC, sensitivity, specificity, accuracy and J index showed high diagnostic accuracy for all chimeric proteins for detection of specific anti-T. cruzi antibodies and differentiated seropositive individuals from those who were seronegative. Our data suggest that these four chimeric proteins are eligible for phase II studies.

  12. Method to conjugate polysaccharide antigens to surfaces for the detection of antibodies.

    Science.gov (United States)

    Boas, Ulrik; Lind, Peter; Riber, Ulla

    2014-11-15

    A new generic method for the conjugation of lipopolysaccharide (LPS)-derived polysaccharide antigens from gram-negative bacteria has been developed using Salmonella as a model. After removal of lipid A from the LPS by mild acidolysis, the polysaccharide antigen was conjugated to polystyrene microbeads modified with N-alkyl hydroxylamine and N-alkyl-O-methyl hydroxylamine surface groups by incubation of antigen and beads for 16 h at 40 °C without the need for coupling agents. The efficiency of the new method was evaluated by flow cytometry in model samples and serum samples containing antibodies against Salmonella typhimurium and Salmonella dublin. The presented method was compared with a similar method for conjugation of Salmonella polysaccharide antigens to surfaces. Here, the new method showed higher antigen coupling efficiency by detecting low concentrations of antibodies. Furthermore, the polysaccharide-conjugated beads showed preserved bioactivity after 1 year of use. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Detection and quantification of Duffy antigen on bovine red blood cell membranes using a polyclonal antibody

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    Ana Teresa B.F. Antonangelo

    2012-09-01

    Full Text Available Babesiosis is one of the most important diseases affecting livestock agriculture worldwide. Animals from the subspecies Bos taurus indicus are more resistant to babesiosis than those from Bos taurus taurus. The genera Babesia and Plasmodium are Apicomplexa hemoparasites and share features such as invasion of red blood cells (RBC. The glycoprotein Duffy is the only human erythrocyte receptor for Pasmodium vivax and a mutation which abolishes expression of this glycoprotein on erythrocyte surfaces is responsible for making the majority of people originating from the indigenous populations of West Africa resistant to P. vivax. The current work detected and quantified the Duffy antigen on Bos taurus indicus and Bos taurus taurus erythrocyte surfaces using a polyclonal antibody in order to investigate if differences in susceptibility to Babesia are due to different levels of Duffy antigen expression on the RBCs of these animals, as is known to be the case in human beings for interactions of Plasmodium vivax-Duffy antigen. ELISA tests showed that the antibody that was raised against Duffy antigens detected the presence of Duffy antigen in both subspecies and that the amount of this antigen on those erythrocyte membranes was similar. These results indicate that the greater resistance of B. taurus indicus to babesiosis cannot be explained by the absence or lower expression of Duffy antigen on RBC surfaces.

  14. Development and Evaluation of a Rapid Antigen Detection and Serotyping Lateral Flow Antigen Detection System for Foot-and-Mouth Disease Virus.

    Directory of Open Access Journals (Sweden)

    Kazuki Morioka

    Full Text Available We developed a lateral flow strip using monoclonal antibodies (MAbs which allows for rapid antigen detection and serotyping of foot-and-mouth disease virus (FMDV. This FMDV serotyping strip was able to detect all 7 serotypes and distinguish serotypes O, A, C and Asia1. Its sensitivities ranged from 10(3 to 10(4 of a 50% tissue culture infectious dose of each FMDV stain; this is equal to those of the commercial product Svanodip (Boehringer Ingelheim Svanova, Uppsala, Sweden, which can detect all seven serotypes of FMDV, but does not distinguish them. Our evaluation of the FMDV serotyping strip using a total of 118 clinical samples (vesicular fluids, vesicular epithelial emulsions and oral and/or nasal swabs showed highly sensitive antigen detection and accuracy in serotyping in accordance with ELISA or RT-PCR. To the best of our knowledge, this is the first report on any FMDV serotyping strip that provides both rapid antigen detection and serotyping of FMDV at the same time on one strip without extra devices. This method will be useful in both FMD-free countries and FMD-infected countries, especially where laboratory diagnosis cannot be carried out.

  15. Detection of toxoplasma gondii antigens in sera from experimentally infected mice

    International Nuclear Information System (INIS)

    Shojaee, S.; Keshavarz, H.; Rezaian, M.; Mohebali, M.

    2007-01-01

    Detection of Toxoplasma antigen in serum of mice by Immunoblotting. strain. IgG isolated from rabbits that were immunized with T. gondii Immunoblotting was performed to detect T. gondii antigens in sera of mice. Serum samples from mice experimentally infected with T. gondii RH strain. The value of Immunoblotting in diagnosis of toxoplasmosis in acute stage of infection. The antigen bands detected in serum sample of mice were experimentally infected with T. gondii tachyzoite in immunoblotting. Six bands demonstrated on seventh post infection day six bands were identified. Similarly on sixth day four bands, on day five three bands and on fourth post infection day two bands were identified. No band was detected in control group sera. Immunoblotting is a sensitive method for diagnosis of acute stage of toxoplasmosis. (author)

  16. Prostate specific antigen velocity does not aid prostate cancer detection in men with prior negative biopsy.

    Science.gov (United States)

    Vickers, Andrew J; Wolters, Tineke; Savage, Caroline J; Cronin, Angel M; O'Brien, M Frank; Roobol, Monique J; Aus, Gunnar; Scardino, Peter T; Hugosson, Jonas; Schröder, Fritz H; Lilja, Hans

    2010-09-01

    Prostate specific antigen velocity has been proposed as a marker to aid in prostate cancer detection. We determined whether prostate specific antigen velocity could predict repeat biopsy results in men with persistently increased prostate specific antigen after initial negative biopsy. We identified 1,837 men who participated in the Göteborg or Rotterdam section of the European Randomized Screening study of Prostate Cancer and who underwent 1 or more subsequent prostate biopsies after an initial negative finding. We evaluated whether prostate specific antigen velocity improved predictive accuracy beyond that of prostate specific antigen alone. Of the 2,579 repeat biopsies 363 (14%) were positive for prostate cancer, of which 44 (1.7%) were high grade (Gleason score 7 or greater). Prostate specific antigen velocity was statistically associated with cancer risk but had low predictive accuracy (AUC 0.55, p <0.001). There was some evidence that prostate specific antigen velocity improved AUC compared to prostate specific antigen for high grade cancer. However, the small increase in risk associated with high prostate specific antigen velocity (from 1.7% to 2.8% as velocity increased from 0 to 1 ng/ml per year) had questionable clinical relevance. Men with prior negative biopsy are at lower risk for prostate cancer at subsequent biopsies with high grade disease particularly rare. We found little evidence to support prostate specific antigen velocity to aid in decisions about repeat biopsy for prostate cancer. 2010 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  17. [Contribution of urinary pneumococcal antigen detection combined with the research of legionella antigen for diagnosis of pneumonia in hospitalized patients].

    Science.gov (United States)

    Honoré, S; Trillard, M; Ould-Hocine, Z; Lesprit, P; Deforges, L; Legrand, P

    2004-10-01

    Bacteriological confirmation of pneumonia (PNM) in hospitalized patients is often erratic or belated. Because of importance of prognosis, early adaptation of treatment requires an empirical antimicrobial therapy (generally aminopenicillin and macrolide combination). The starting therapeutic strategy should profit by a fast and reliable test asserting a pneumococcal etiology. The Binax Now S. pneumoniae (BNP) test allows an urinary pneumococcal antigen (UPA) detection using an immunochromatographic membrane assay within 15 minutes. We first evaluated the BNP test for 28 patients with pneumococcal PNM proved by culture, and 118 negative control patients without PNM. The BNP test was then evaluated by testing urine from 158 hospitalized patients with a clinical picture of PNM (community-acquired: 90, nosocomial: 68) for whom a research of urinary Legionella antigen (Binax Now) was prescribed and was positive for only two cases. 57 patients (36.1%) were hospitalized in ICU. The sensitivity was 71.4% (85.7% for the 21 bacteriemic PNM), and the specificity was 98.3%; that is consistent with previous published data. Among the 158 patients with PNM, UPA was detected in 17 cases (10.8%): 15 within the community-acquired PNM (16.7%) and 2 (2.9%) within the nosocomial cases. The pneumococcal etiology was confirmed by bacteriological samples in 7/17 patients (6 by blood cultures). The 10 others showed clinical and radiological features in agreement with a pneumococcal PNM. Among the 141 patients with negative AUP, S. pneumoniae was isolated from 6 of them (2 in blood cultures). The Binax Now S. pneumoniae test allowed a fast and reliable etiological diagnosis in 10.8% of hospitalized PNM (16.7% of the community-acquired cases) having a research of urinary Legionella antigen (conceiving with severity factors). So it could conduce to an improved adjustment of the starting antimicrobial therapy of hospitalized adult patients with PNM.

  18. Shape anisotropy enhanced optomagnetic measurement for prostate-specific antigen detection via magnetic chain formation

    DEFF Research Database (Denmark)

    Tian, Bo; Wetterskog, Erik; Qiu, Zhen

    2017-01-01

    anisotropy), and directly increasing the optomagnetic signal (via optical shape anisotropy). We achieve a limit of detection (LOD) of 5.5 pM (0.82 ng/mL) for the detection of a model multivalent molecule, biotinylated anti-streptavidin, in PBS. For the measurements of prostate-specific antigen (PSA) in 50...

  19. Indirect solid-phase immunosorbent assay for detection of arenavirus antigens and antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, A P; Rezapkin, G V; Dzagurova, T K; Tkachenko, E A [Institute of Poliomyelitis anU Viral Encephalities of the U.S.S.R. Academy of Medical Sciences, Moscow

    1984-05-01

    Indirect enzyme-linked immunosorbent assay (ELISA) and solid phase radioimmunoassay (SPRIA) using either enti-human or anti-mouse IgG labelled with horseradish peroxidase and /sup 125/I, respectively, were developed for the detection of Junin, Machupo, Tacaribe, Amapari, Tamiami, Lassa and LCM arenaviruses. Both methods allow high sensitivity detection of arenavirus antigens and antibodies.

  20. Radioimmunoassay for detecting antibodies against murine malarial parasite antigens: monoclonal antibodies recognizing Plasmodium yoelii antigens

    International Nuclear Information System (INIS)

    Kim, K.J.; Taylor, D.W.; Evans, C.B.; Asofsky, R.

    1980-01-01

    A solid-phase radioimmunoassay (SPRIA) in microtiter wells was established for detecting antibodies against Plasmodium yoelii Ag. The SPRIA was found (1) to require as little as 5 μg of crude parasite Ag per well, (2) to be able to detect 0.5 ng of monoclonal Ab, and (3) to be 10 4 times more sensitive than the indirect fluorescent Ab staining technique. In a modification of the above assay using intact RBC as an Ag, hyperimmune serum showed significant binding to the surface of erythrocytes of mice infected with P. yoelii parasites but not to RBC of normal mice. Hybridomas were prepared by fusing infected mouse spleen cells with myeloma cells. Using the SPRIA, hybrids secreting Ab against P. yoelii 17XL Ag were detected

  1. Dengue NS1 Antigen - for Early Detection of Dengue Virus Infection

    Directory of Open Access Journals (Sweden)

    Amol Hartalkar

    2015-08-01

    Full Text Available Objectives: To evaluate the efficacy of NS1 antigen assay for early diagnosis of dengue virus infection in a tertiary care hospital. Methods: This cross sectional study was carried out in department of Medicine from August to December 2013. Total 100 patients with dengue fever were included. Complete blood count, alanine aminotransferase (ALT, aspartate aminotransferase (AST, Dengue NS1 antigen and IgM and IgG antibodies of dengue virus were done in all cases. Results: Of the 100 sera tested, 75% were positive for dengue virus infection based on dengue NS1 antigen, IgM antibody and IgG antibody. Dengue NS1 antigen and IgM, IgG antibody were able to detect dengue virus infection between day 1 to day 8 in 92% of samples, 86.7% of samples and 82.6% of samples respectively. Sixty nine percent (69% were found positive for dengue NS1 antigen, 65% were IgM positive and 62% were IgG positive. Based on the dengue NS1 antigen and IgM antibody combination, 74% were positive for dengue virus infections. Sensitivity of Dengue NS1 antigen was 92.3% and specificity of 74.28% in comparison to IgM antibody. Detection rate increased to 75%, based on the antigen and IgG antibody combination. Sensitivity of dengue NS1 antigen was 90.3% and specificity of 65.8% in comparison to IgG antibody. Conclusion: Dengue NS1 antigen is a useful, sensitive and specific test for early diagnosis of dengue virus infection and it improves diagnostic efficiency in combination with antibody test. Key words: Dengue fever, NS1 antigen. Introduction: Dengue fever (DF is the most common arboviral illness in humans. Each year, an estimated 50-100 million cases of dengue fever and 500,000 cases of dengue hemorrhagic fever occur worldwide, with 30000 deaths (mainly in children. Globally 2.5-3 billion people in approximately 112 tropical and subtropical countries are at risk of dengue.of samples respectively. Sixty nine percent (69% were found positive for dengue NS1 antigen, 65% were Ig

  2. Pelacakan Secara Imunohistokimiawi Antigen Virus pada Ayam yang Diinfeksi dengan Virus Penyakit Tetelo (IMMUNOHISTOCHEMICAL DETECTION OF VIRAL ANTIGEN IN TISSUE OF CHICKENS EXPERIMENTALLY INFECTED WITH NEWCASTLE DISEASE VIRUS

    Directory of Open Access Journals (Sweden)

    Anak Agung Ayu Mirah Adi

    2013-07-01

    Full Text Available In order to study the distribution of Newcastle disease virus (NDV following infection, chickenswere experimentally infected with visceretropic velogenic NDV isolate. Monoclonal antibodies (mAbsagainst the NDV LaSota vaccine strain were then produced to detect viral antigen in the infectedorgans. The mAbs were firstly tested for their specificity by enzyme linked immunosorbent assay(ELISA using NDV and normal allantoic fluids as antigens. Eight mAbs specific against NDVwere isolated and two mAbs were used for immunodetection of NDV antigen in chicken’s tissues.By immunohistochemistry labeled streptavidin-biotin (LSAB staining NDV–antigen was detectedin paraffin embedded tissues of NDV-infected chickens. NDV antigen was not detected in noninfected chickens. In the infected chickens, high intensity of NDV antigen was detected in thelymphoid tissues, lung and intestine. The NDV antigen with a lesser intensity was detected in thebrain, trachea, liver and myocardium. This study shows that although viscerotropic velogenicNDV isolate can infect almost all organs, the main target of infection are lung, intestine andlymphoids tissues

  3. Synthetic oligonucleotide antigens modified with locked nucleic acids detect disease specific antibodies

    DEFF Research Database (Denmark)

    Samuelsen, Simone V; Solov'yov, Ilia A.; Balboni, Imelda M.

    2016-01-01

    New techniques to detect and quantify antibodies to nucleic acids would provide a significant advance over current methods, which often lack specificity. We investigate the potential of novel antigens containing locked nucleic acids (LNAs) as targets for antibodies. Particularly, employing...... molecular dynamics we predict optimal nucleotide composition for targeting DNA-binding antibodies. As a proof of concept, we address a problem of detecting anti-DNA antibodies that are characteristic of systemic lupus erythematosus, a chronic autoimmune disease with multiple manifestations. We test the best...... that the novel method is a promising tool to create antigens for research and point-of-care monitoring of anti-DNA antibodies....

  4. Construction, expression, purification and biotin labeling of a single recombinant multi-epitope antigen for double-antigen sandwich ELISA to detect hepatitis C virus antibody.

    Science.gov (United States)

    He, Jing; Xiu, Bingshui; Wang, Guohua; Chen, Kun; Feng, Xiaoyan; Song, Xiaoguo; Zhu, Cuixia; Yang, Xiqin; Bai, Guanzhong; Ling, Shigan; Zhang, Heqiu

    2011-08-01

    Based on B cell epitope predictions, a recombinant antigen with multiple epitopes from four Hepatitis C Virus fragments (C, NS3, NS4 and NS5) were engineered. The recombinant gene was then highly expressed in E. coli. The non-modified and C-terminal-modified recombinant proteins were used for coating and biotin labeling, respectively, to establish the double-antigen sandwich ELISA. Ten positive reference samples confirmed by the CHIRON RIBA HCV 3.0 SIA kit were detected positive, Forty one plasma samples were positive among samples from 441 volunteers, which indicated that the recombinant antigen could readily react well with plasma HCV antibody. As critical reagents of double-antigen sandwich ELISA, the recombinant multi-epitope antigen and the C-terminal-modified and biotin-conjugated antigen show good antigenicity. In this study, we provide a simple approach to produce multiple epitopes within one recombinant protein in order to avoid the costly expression of less-effective pools of multiple proteins, which is the conventional strategy of diagnostic antigen production for HCV antibody detection.

  5. Radioimmunoassay in the detection of the hepatitis Be antigen/antibody system in asymptomatic carriers of hepatitis B surface antigen

    International Nuclear Information System (INIS)

    Pastore, G.; Dentico, P.; Angarano, G.; Schiraldi, O.; Zanetti, A.R.; Ferroni, P.

    1980-01-01

    A radioimmunoassay for hepatitis e antigen (HBeAg) and antibody to e (anti-HBe) was developed and sera of 71 asymptomatic chronic carriers of hepatitis B surface antigen (HBsAg), in 44 of whom liver biopsy was obtained, were tested. In addition, testing for Dane particle associated DNA polymerase activity was performed in all sera. HBeAg was detected in 14 subjects (19.7%) and anti-HBe in 46 (64.8%). The highest proportion of HBeAg positivity (40%) was found among carriers with histological evidence of chronic hepatitis, whereas anti-HBe was present in 80% of carriers with normal liver histology, in 58% of carriers with non-specific reactive hepatitis and in 60% of carriers with chronic liver lesions. DNA polymerase activity was present in 92.8% of sera positive for HBeAg, in 13% of sera positive for anti HBe, and in 9% of sera negative for both markers. Our results demonstrate that not all HBsAg carriers reactive to HBeAg show evidence of chronic hepatitis nor, conversely, that anti-HBe is invariably associated with the healthy carrier state of HBsAg. Finally, circulating Dane particles, as revealed by the presence of serum specific DNA polymerase activity, may also be present in anti-HBe positive sera other than those of some HBsAg carriers lacking both HBeAg and anti-HBe. (orig.) [de

  6. Detection of antigens of allergic diseases in children by radioallergosorbent test (RAST), 1

    International Nuclear Information System (INIS)

    Hirooka, Junko

    1977-01-01

    Detection of antigens mainly by RAST, measurement of immunoglobulin, and investigation of clinical history were performed on children with intractable bronchial asthma. The results were compared with those in cases of mild or moderate degree, and they were discussed. The obtained results were as follows: 1) Cases, of which the occurrence age of disease was under 2 years old, hold a majority in intractable cases, and the ratio was twice that of the control group. 2) A result of skin test was generally lower positive rate in the intractable group as compared to the control group. However, a result of prick test for buckwheat antigen in the intractable group showed higher positive rate than that in the control group. The intractable group tended to be separated into two extreme groups, one which showed positive to most of inhaled antigens in skin test, and another which showed negative to all antigens. 3) As a result of RAST, 13% of the intractable group showed positive to egg white out of food antigens, and it was three times the ratio of positive in the control group. One case showed strong positive to rice. 4) Two thirds of cases which showed positive in RAST for food antigens showed negative in prick test. 5) Total IgE in the serum of the intractable group was clearly lower in values than that of the control group. (Tsunoda, M.)

  7. Detection of avian influenza antibodies and antigens in poultry and ...

    African Journals Online (AJOL)

    Using HI test, the wild birds were negative for AI (H5) antibodies but ELISA detected AI (NP) antibodies in Black Stork (Ciconia nigra) with an overall seroprevalence of 4.5% and mean titre of 24.50±2.400 EU. Cloacal swabs from the same species of wild birds that were tested for antibodies and 710 oropharyngeal swabs ...

  8. Rapid solid-phase radioimmunoassay for detection of equine infectious anemia viral antigen and antibodies: parameters involved in standardization

    International Nuclear Information System (INIS)

    Horenstein, A.L.; Feinstein, R.E.

    1985-01-01

    Solid-phase radioimmunoassays (SPRIA) are described for the detection of equine infectious anemia (EIA) viral antigen and antibodies. Protein-antigen P29 currently used in the agar-gel immunodiffusion (AGID) test was used as antigen in the SPRIA. The specificity of the reaction was assessed by inhibition with the antigen. The reaction of immune serum against EIA-virus antigen adsorbed to the wells, was completely inhibited by the antigen in solution. This property was applied in an indirect competitive SPRIA for the detection of viral protein P29. The detection threshold of the SPRIA for EIA virus protein was about 5 ng and about 1 ng of antibody can be detected. The assay is rapid, specific and sensitive and allows the testing of multiple serum samples with the advantage of employing a single secondary labelled antibody. (orig.)

  9. Comparison between an immunochromatographic test with an amplified ELISA for detecting e antigen and anti-e antigen antibodies in chronic Hepatitis B

    International Nuclear Information System (INIS)

    Mainet Gonzalez, Damian; Palenzuela Gardon, Daniel O; Aguilar Rubido; Julio C

    2009-01-01

    The disappearance of the e antigen and the appearance of anti-e antigen antibodies are two biomarkers that indicate favorable prognosis in Hepatitis B. In this study the Advanced QualityTM immunochromatographic test for detecting those biomarkers was compared to the Vidas semi-quantitative ELISA test. Our hypothesis was that it is possible to use these biomarkers measured in a rapid and simple Advanced QualityTM immunochromatographic test for evaluating the therapeutic response in clinical trials with chronic hepatitis B patients. The two methods were done following the manufacturer's instructions. The sera were taken from 69 patients with chronic hepatitis B of the clinical trial of the CIGB 440 therapeutic candidate. The immunochromatographic test and ELISA for detecting e antigen and anti-e antigen antibodies presented from substantial to almost perfect agreement in the evaluation of the sera of chronic Hepatitis B patients in a clinical trial. The immunochromatographic test for detecting e antigen had a low positive average agreement and a high negative average agreement compared to the ELISA. Nevertheless, the immunochromatographic test for detecting anti-e antigen antibodies had a high negative and positive average agreement in comparison to the ELISA. The immunochromagraphic test for the e antigen had a lower positive average agreement compared to the ELISA and some patients infected with Hepatitis B virus could not be detected by the former assay. The immunochromatographic test for anti-e antigen antibodies showed a similar performance to that of ELISA and could therefore be used in clinical trials for chronic Hepatitis B in health institutions without the need of a highly qualified lab technician. (author)

  10. Detection of Helicobacter pylori urease antigen in saliva in patients with different gastric H. pylori status.

    Science.gov (United States)

    El Khadir, Mounia; Alaoui Boukhris, Samia; Benajah, Dafr-Allah; El Rhazi, Karima; Ibrahimi, Sidi Adil; El Abkari, Mohamed; Harmouch, Taoufiq; Nejjari, Chakib; Mahmoud, Mustapha; Benlemlih, Mohamed; Bennani, Bahia

    2016-07-01

    Finding a simple, accurate, and noninvasive diagnosis method is a substantial challenge for the detection of Helicobacter pylori. The aim of the present study was to compare the presence of H. pylori urease antigen in saliva with the presence of this bacterium in gastric mucosa. Saliva samples and gastric biopsies were taken from 153 consenting Moroccan patients. Saliva samples were analyzed using an immunochromatographic test for urease antigen H. pylori detection. Thereafter, the gastric biopsies were analyzed by histology and polymerase chain reaction (PCR) to detect this bacterium. From a total of 153 recruited Moroccan patients, H. pylori was detected in 28 (18.30%), 87 (57.24%), and 69 (45.10%) cases by saliva test, histology, and PCR, respectively. A significant association was observed between the presence of H. pylori antigen in saliva and age. However, no association was found with sex, H. pylori virulence factors, gastric disease outcome, and density of the bacterium on the gastric mucosa. Considering that only 90 patients presented concordant results on H. pylori diagnosis (positive or negative) by both histology and PCR, the immunochromatographic test showed very low sensitivity (29.79%) and high specificity (90.70%). Of these two tests, the positive and negative predictive values were 77.78% and 54.17%, respectively. The accuracy of the test for salivary detection of urease antigen H. pylori was 58.89%. This study demonstrated a low detection rate of H. pylori antigens in saliva compared with the presence of this bacterium in gastric mucosa, suggesting that saliva cannot be used as a suitable sample for the diagnosis of H. pylori in our study population. Copyright © 2016. Published by Elsevier Taiwan LLC.

  11. Detection of B-lymphocytes secreting antibodies to Dermatophagoides antigens

    DEFF Research Database (Denmark)

    Sparholt, S H; Barington, T; Schou, C

    1991-01-01

    Alutard, showed that 1 week after injection, circulating allergen-specific antibody-secreting cells (AbSC) were detected with this assay. The ranges were between 1 and 13 IgM-, 2 and 20 IgG- and 20 and 55 IgA allergen-specific AbSC per 10(6) MNC. It is expected that this assay will help to understand more...

  12. Detecting West Nile virus in owls and raptors by an antigen-capture assay.

    Science.gov (United States)

    Gancz, Ady Y; Campbell, Douglas G; Barker, Ian K; Lindsay, Robbin; Hunter, Bruce

    2004-12-01

    We evaluated a rapid antigen-capture assay (VecTest) for detection of West Nile virus in oropharyngeal and cloacal swabs, collected at necropsy from owls (N = 93) and raptors (N = 27). Sensitivity was 93.5%-95.2% for northern owl species but raptors.

  13. KAtex antigen-detection test as a diagnostic tool for latent visceral ...

    African Journals Online (AJOL)

    SERVER

    2008-04-03

    Apr 3, 2008 ... Urine samples were tested by kAtex kit to detect VL antigen. All sera .... IFA, and ELISA-IgG and IgM) to finding of agreement and validity and reliability .... Animal inoculation is not usually employed as a diag- nostic test, since ...

  14. Detection of urinary excreted fungal galactomannan-like antigens for diagnosis of invasive aspergillosis.

    Directory of Open Access Journals (Sweden)

    Simon F Dufresne

    Full Text Available Mortality associated with invasive aspergillosis (IA remains high, partly because of delayed diagnosis. Detection of microbial exoantigens, released in serum and other body fluids during infection, may help timely diagnosis. In course of IA, Aspergillus galactomannan (GM, a well established polysaccharide biomarker, is released in body fluids including urine. Urine is an abundant, safely collected specimen, well-suited for point-of-care (POC testing, which could play an increasing role in screening for early disease. Our main objective was to demonstrate GM antigenuria as a clinically relevant biological phenomenon in IA and establish proof-of-concept that it could be translated to POC diagnosis. Utilizing a novel IgM monoclonal antibody (MAb476 that recognizes GM-like antigens from Aspergillus and other molds, we demonstrated antigenuria in an experimental animal IA model (guinea pig, as well as in human patients. In addition, we investigated the chemical nature of the urinary excreted antigen in human samples, characterized antigen detection in urine by immunoassays, described a putative assay inhibitor in urine, and indicated means of alleviation of the inhibition. We also designed and used a lateral flow immunochromatographic assay to detect urinary excreted antigen in a limited number of IA patient urine samples. In this study, we establish that POC diagnosis of IA based on urinary GM detection is feasible. Prospective studies will be necessary to establish the performance characteristics of an optimized device and define its optimal clinical use.

  15. Detecting West Nile Virus in Owls and Raptors by an Antigen-capture Assay

    OpenAIRE

    Gancz, Ady Y.; Campbell, Douglas G.; Barker, Ian K.; Lindsay, Robbin; Hunter, Bruce

    2004-01-01

    We evaluated a rapid antigen-capture assay (VecTest) for detection of West Nile virus in oropharyngeal and cloacal swabs, collected at necropsy from owls (N = 93) and raptors (N = 27). Sensitivity was 93.5%–95.2% for northern owl species but

  16. Evaluation of five hepatitis delta virus marker assays for detection of antigen and antibody.

    OpenAIRE

    Bezeaud, A; Rosenswajg, M; Guillin, M C

    1989-01-01

    Five commercially available assays for hepatitis delta (HD) virus markers were compared for sensitivity, specificity, and reproducibility: three assays for antibody (anti-HD), provided by Diagnostics Pasteur, Organon Teknika, and Abbott Laboratories, and two assays for antigen (HD Ag), from Pasteur and Organon Teknika. The assay from Organon Teknika is the less sensitive assay for anti-HD detection. Although the sensitivities of the Pasteur and Abbott assays for anti-HD detection are similar,...

  17. Comparison of excretory-secretory antigen and positive faecal supernatant antigen in the detection of Echinococcus granulosus infection in dogs by CIEP

    Directory of Open Access Journals (Sweden)

    P. R. Prathiush

    Full Text Available Coproantigen detection of Echinococcosis in dogs by counter immunoelectrophoresis was standardized. Adult Echinococcus granulosus worms were obtained from intestine of a necropsied positive dog. Excretory-secretory antigen was prepared by culturing adult worms in Medium 199 (pH 7.4. Faeces of positive dog were collected and fecal supernatant was prepared and used for coproantigen detection. CIEP was carried out using tris-borate buffer (pH 8.0 at a constant current of 8mA/slide for 60 minutes. CIEP detected infection with both the antigens. [Vet World 2009; 2(11.000: 421-422

  18. Follow-up of neurocysticercosis patients after treatment using an antigen detection ELISA

    Directory of Open Access Journals (Sweden)

    Nguekam

    2003-03-01

    Full Text Available Seven patients with active neurocysticercosis (NCC received an eight days treatment with albendazole and were followed up using computed tomography (CT-scan and a monoclonal antibody based ELISA for the detection of circulating antigen (Ag-ELISA. Only three patients were cured as was shown by CT-scan and by the disappearance of circulating antigens one month after treatment. After a second course of albendazole therapy, two other patients became seronegative. CT-scan showed the disappearance of viable cysts in all persons who became seronegative whereas patients who were not cured remained seropositive. These preliminary results show that this Ag-ELISA is a promising technique for monitoring the success of treatment of NCC patients because of the excellent correlation between the presence of circulating antigens and of viable brain cysts.

  19. Detection of avian influenza antigens in proximity fiber, droplet, and optical waveguide microfluidics

    Science.gov (United States)

    Yoon, Jeong-Yeol; Heinze, Brian C.; Gamboa, Jessica; You, David J.

    2009-05-01

    Virus antigens of avian influenza subtype H3N2 were detected on two different microfluidic platforms: microchannel and droplet. Latex immunoagglutination assays were performed using 920-nm highly carboxylated polystyrene beads that are conjugated with antibody to avian influenza virus. The bead suspension was merged with the solutions of avian influenza virus antigens in a Y-junction of a microchannel made by polydimethylsiloxane soft lithography. The resulting latex immunoagglutinations were measured with two optical fibers in proximity setup to detect 45° forward light scattering. Alternatively, 10 μL droplets of a bead suspension and an antigen solution were merged on a superhydrophobic surface (water contact angle = 155°), whose movement was guided by a metal wire, and 180° back light scattering is measured with a backscattering optical probe. Detection limits were 0.1 pg mL-1 for both microchannel with proximity fibers and droplet microfluidics, thanks to the use of micro-positioning stages to help generate reproducible optical signals. Additionally, optical waveguide was tested by constructing optical waveguide channels (filled with mineral oil) within a microfluidic device to detect the same light scattering. Detection limit was 0.1 ng mL-1 for an optical waveguide device, with a strong potential of improvement in the near future. The use of optical waveguide enabled smaller device setup, easier operation, smaller standard deviations and broader linear range of assay than proximity fiber microchannel and droplet microfluidics. Total assay time was less than 10 min.

  20. Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool.

    Science.gov (United States)

    Mesquita, Flávio da Silva; Oliveira, Danielle Bruna Leal de; Crema, Daniela; Pinez, Célia Miranda Nunes; Colmanetti, Thaís Cristina; Thomazelli, Luciano Matsumia; Gilio, Alfredo Elias; Vieira, Sandra Elisabeth; Martinez, Marina Baquerizo; Botosso, Viviane Fongaro; Durigon, Edison Luiz

    The aim of this study was to evaluate the QuickVue ® RSV Test Kit (QUIDEL Corp, CA, USA) as a screening tool for respiratory syncytial virus in children with acute respiratory disease in comparison with the indirect immunofluorescence assay as gold standard. In Brazil, rapid antigen detection tests for respiratory syncytial virus are not routinely utilized as a diagnostic tool, except for the diagnosis of dengue and influenza. The authors retrospectively analyzed 486 nasopharyngeal aspirate samples from children under age 5 with acute respiratory infection, between December 2013 and August 2014, the samples were analyzed by indirect immunofluorescence assay and QuickVue ® RSV Test kit. Samples with discordant results were analyzed by real time PCR and nucleotide sequencing. From 313 positive samples by immunofluorescence assays, 282 (90%) were also positive by the rapid antigen detection test, two were positive only by rapid antigen detection test, 33 were positive only by immunofluorescence assays, and 171 were positive by both methods. The 35 samples with discordant results were analyzed by real time PCR; the two samples positive only by rapid antigen detection test and the five positive only by immunofluorescence assays were also positive by real time PCR. There was no relation between the negativity by QuickVue ® RSV Test and viral load or specific strain. The QuickVue ® RSV Test showed sensitivity of 90%, specificity of 98.8%, predictive positive value of 99.3%, and negative predictive value of 94.6%, with accuracy of 93.2% and agreement κ index of 0.85 in comparison to immunofluorescence assay. This study demonstrated that the QuickVue ® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics. Copyright © 2016 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  1. Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool,

    Directory of Open Access Journals (Sweden)

    Flávio da Silva Mesquita

    Full Text Available Abstract Objective: The aim of this study was to evaluate the QuickVue® RSV Test Kit (QUIDEL Corp, CA, USA as a screening tool for respiratory syncytial virus in children with acute respiratory disease in comparison with the indirect immunofluorescence assay as gold standard. In Brazil, rapid antigen detection tests for respiratory syncytial virus are not routinely utilized as a diagnostic tool, except for the diagnosis of dengue and influenza. Methods: The authors retrospectively analyzed 486 nasopharyngeal aspirate samples from children under age 5 with acute respiratory infection, between December 2013 and August 2014, the samples were analyzed by indirect immunofluorescence assay and QuickVue® RSV Test kit. Samples with discordant results were analyzed by real time PCR and nucleotide sequencing. Results: From 313 positive samples by immunofluorescence assays, 282 (90% were also positive by the rapid antigen detection test, two were positive only by rapid antigen detection test, 33 were positive only by immunofluorescence assays, and 171 were positive by both methods. The 35 samples with discordant results were analyzed by real time PCR; the two samples positive only by rapid antigen detection test and the five positive only by immunofluorescence assays were also positive by real time PCR. There was no relation between the negativity by QuickVue® RSV Test and viral load or specific strain. The QuickVue® RSV Test showed sensitivity of 90%, specificity of 98.8%, predictive positive value of 99.3%, and negative predictive value of 94.6%, with accuracy of 93.2% and agreement κ index of 0.85 in comparison to immunofluorescence assay. Conclusions: This study demonstrated that the QuickVue® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics.

  2. Detection and Characterization of Autoantibodies to Neuronal Cell-Surface Antigens in the Central Nervous System

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    Marleen eVan Coevorden-Hameete

    2016-05-01

    Full Text Available Autoimmune encephalitis (AIE is a group of disorders in which autoantibodies directed at antigens located on the plasma membrane of neurons induce severe neurological symptoms. In contrast to classical paraneoplastic disorders, AIE patients respond well to immunotherapy. The detection of neuronal surface autoantibodies in patients’ serum or CSF therefore has serious consequences for the patients’ treatment and follow-up and requires the availability of sensitive and specific diagnostic tests. This mini-review provides a guideline for both diagnostic and research laboratories that work on the detection of known surface autoantibodies and/or the identification of novel surface antigens. We discuss the strengths and pitfalls of different techniques for anti-neuronal antibody detection: 1 Immunohistochemistry and immunofluorescence on rat/ primate brain sections, 2 Immunocytochemistry of living cultured hippocampal neurons, 3 Cell Based Assay (CBA. In addition, we discuss the use of immunoprecipitation and mass spectrometry analysis for the detection of novel neuronal surface antigens, which is a crucial step in further disease classification and the development of novel CBAs.

  3. A solid phase radio immunoassay on hydrophobic membrane filters: detection of antibodies to gonocal surface antigens

    International Nuclear Information System (INIS)

    Lambden, P.R.; Watt, P.J.

    1978-01-01

    A solid phase radioimmunoassay (SPRIA) has been developed for detection of IgG antibodies to gonococcal outer membrane components. Gonococcal antigens was immobilised on a solid support by covalent coupling to CNBr-activated Sepharose in the presence of the detergent Triton X-100. Binding of specific antibody to the Sepharose-antigen complex was detected using radiolabelled Protein A as the antiglobulin. Protein A was labelled by radioacetylation with tritiated acetic anhydride, yielding a product of high specific activity and high stability. No detectable loss of activity was observed over a ten month period. The entire assay was performed on Mitex teflon hydrophobic membrane filters which held the Sepharose beads and aqueous supernatant as a discrete drop of liquid. The supernatants and incubation were easily and rapidly removed from the beads by suction on a specially-designed manifold system. This procedure removed the need for repeated and time-consuming centrifugations. Titres were obtained graphically from double log plots of cpm bound versus antiserum dilution by extrapolation of the straight line to a point corresponding to twice the control level of radioactivity binding. The assay proved to be a very reliable and simple procedure for the detection of IgG antibodies to gonococcal surface antigens. (Auth.)

  4. Comparative efficacy of antigen and antibody detection tests for human trichinellosis

    International Nuclear Information System (INIS)

    Ivanoska, D.; Cuperlovic, K.; Gamble, H.R.; Murrell, K.D.

    1989-01-01

    Sera collected from patients with suspected or confirmed exposure to Trichinella spiralis were tested for circulating parasite antigens and antiparasite antibodies. Using an immunoradiometric assay, excretory--secretory antigens from muscle-stage larvae of T. spiralis were detected in the sera of 47% of 62 patients with clinical trichinellosis and 13% of 39 patients without clinical signs but suspected of exposure to infected meat. In comparison, antibodies were detected using an indirect immunofluorescent test in the circulation of 100% of the 62 patients with clinical trichinellosis and 46% of the 39 patients with suspected exposure. The presence of antibodies specific to excretory-secretory products of T. spiralis muscle larvae was confirmed in the majority of the samples tested by a monoclonal antibody-based competitive inhibition assay. These results indicate that antibody detection is a more sensitive diagnostic method for human trichinellosis, but that antigen detection might be a useful confirmatory test because it is a direct demonstration of parasite products in the circulation

  5. Design of indirect solid-phase immunosorbent methods for detecting arenavirus antigens and antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Ivanov, A P; Rezapkin, G V; Dzagurova, T K; Tkachenko, E A

    1984-05-01

    Specifications have been elaborated for formulating indirect solid-phase enzyme-linked immunosorbent assay (ELISA) and radioimmunoassay (SPRIA) methods that employ anti-human and anti-mice G class immunoglobulin (IgG), conjugated with horseradish peroxidase and /sup 125/I for detecting the arenaviruses Junin, Machupo, Tacaribe, Amalpari, Tamiami, Lassa, and LCM (lymphocytic choriomeningitis). These methods make it possible to identify with a high degree of sensitivity arenavirus antigens and antibodies in various kinds of material.

  6. Detection of soluble antigens of Toxoplasma gondii by a four-layer modification of an enzyme immunoassay.

    Science.gov (United States)

    Turunen, H J

    1983-01-01

    A sensitive four-layer modification of an enzyme immunoassay for the detection of soluble antigens of Toxoplasma gondii is described. Microtiter plates were sensitized with rabbit anti-toxoplasma immunoglobulins (6 micrograms/ml) used as the primary antibodies; guinea pig anti-toxoplasma immunoglobulins (6 micrograms/ml) were used as the secondary trapping antibodies. Horseradish peroxidase-conjugated anti-guinea pig immunoglobulins were used as the indicator antibodies. The specificity of the antigen assay was confirmed by using guinea pig immunoglobulins from preimmunization sera. The sensitivity of the antigen assay was found to be at least 10 ng of antigen protein per ml. The suitability of the method for detecting antigens of T. gondii in different specimens was studied by experimental toxoplasma infection in mice. Antigenic components of T. gondii could be detected in different tissue specimens from infected animals from the first day after infection onwards. Toxoplasma antigen in serum and urine samples from infected mice reached detectable levels on day 2 after infection followed by a linear increase in antigen concentration in succeeding samples. This method might offer a valuable aid for a rapid etiological diagnosis also in human cases of acute toxoplasmosis. PMID:6345574

  7. ELISA for detection of variant rabbit haemorrhagic disease virus RHDV2 antigen in liver extracts.

    Science.gov (United States)

    Dalton, K P; Podadera, A; Granda, V; Nicieza, I; Del Llano, D; González, R; de Los Toyos, J R; García Ocaña, M; Vázquez, F; Martín Alonso, J M; Prieto, J M; Parra, F; Casais, R

    2018-01-01

    The emergence and rapid spread of variant of the rabbit hemorrhagic disease virus (RHDV2) require new diagnostic tools to ensure that efficient control measures are adopted. In the present study, a specific sandwich enzyme-linked immunosorbent assay (ELISA) for detection of RHDV2 antigens in rabbit liver homogenates, based on the use of an RHDV2-specific monoclonal antibody (Mab) 2D9 for antigen capture and an anti-RHDV2 goat polyclonal antibody (Pab), was developed. This ELISA was able to successfully detect RHDV2 and RHDV2 recombinant virions with high sensitivity (100%) and specificity (97.22%). No cross-reactions were detected with RHDV G1 viruses while low cross-reactivity was detected with one of the RHDVa samples analyzed. The ELISA afforded good repeatability and had high analytical sensitivity as it was able to detect a dilution 1:163,640 (6.10ng/mL) of purified RHDV-N11 VLPs, which contained approximately 3.4×10 8 molecules/mL particles. The reliable discrimination between closely related viruses is crucial to understand the epidemiology and the interaction of co-existing pathogens. In the work described here we design and validate an ELISA for laboratory based, specific, sensitive and reliable detection of RHDVb/RHDV2. This ELISA is a valuable, specific virological tool for monitoring virus circulation, which will permit a better control of this disease. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Epigenetics in schistosomes: what we know and what we need know

    Directory of Open Access Journals (Sweden)

    Liu Weiwei

    2016-11-01

    Full Text Available Schistosomes are metazoan parasites and can cause schistosomiasis. Epigenetic modifications include DNA methylation, histone modifications and non-coding RNAs. Some enzymes involved in epigenetic modification and microRNA processes have been developed as drugs to treat the disease. Compared with humans and vertebrates, an in-depth understanding of epigenetic modifications in schistosomes is starting to be realized. DNA methylation, histone modifications and non-coding RNAs play important roles in the development and reproduction of schistosomes and in interactions between the host and schistosomes. Therefore, exploring and investigating the epigenetic modifications in schistosomes will facilitate drug development and therapy for schistosomiasis. Here, we review the role of epigenetic modifications in the development, growth and reproduction of schistosomes, and the interactions between the host and schistosome. We further discuss potential epigenetic targets for drug discovery for the treatment of schistosomiasis.

  9. Schistosome syntenin partially protects vaccinated mice against Schistosoma mansoni infection.

    Directory of Open Access Journals (Sweden)

    Barbara C Figueiredo

    2014-08-01

    Full Text Available Schistosomiasis is a neglected tropical disease caused by several species of trematode of the genus Schistosoma. The disease affects more than 200 million people in the world and causes up to 280,000 deaths per year, besides having high morbidity due to chronic illness that damages internal organs. Current schistosomiasis control strategies are mainly based on chemotherapy, but many researchers believe that the best long-term strategy to control disease is a combination of drug treatment and immunization with an anti-schistosome vaccine. Among the most promising molecules as vaccine candidates are the proteins present in the tegument and digestive tract of the parasite.In this study, we describe for the first time Schistosoma mansoni syntenin (SmSynt and we evaluate its potential as a recombinant vaccine. We demonstrate by real-time PCR that syntenin is mainly expressed in intravascular life stages (schistosomula and adult worms of the parasite life cycle and, by confocal microscopy, we localize it in digestive epithelia in adult worms and schistosomula. Administration of siRNAs targeting SmSynt leads to the knock-down of syntenin gene and protein levels, but this has no demonstrable impact on parasite morphology or viability, suggesting that high SmSynt gene expression is not essential for the parasites in vitro. Mice immunization with rSmSynt, formulated with Freund's adjuvant, induces a Th1-type response, as suggested by the production of IFN-γ and TNF-α by rSmSynt-stimulated cultured splenocytes. The protective effect conferred by vaccination with rSmSynt was demonstrated by 30-37% reduction of worm burden, 38-43% reduction in the number, and 35-37% reduction in the area, of liver granulomas.Our report is the first characterization of syntenin in Schistosoma mansoni and our data suggest that this protein is a potential candidate for the development of a multi-antigen vaccine to control schistosomiasis.

  10. Detection of Puumala hantavirus antigen in human intestine during acute hantavirus infection.

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    Joerg Latus

    Full Text Available BACKGROUND: Puumala virus (PUUV is the most important hantavirus species in Central Europe. Nephropathia epidemica (NE, caused by PUUV, is characterized by acute renal injury (AKI with thrombocytopenia and frequently gastrointestinal symptoms. METHODS: 456 patients with serologically and clinically confirmed NE were investigated at time of follow-up in a single clinic. The course of the NE was investigated using medical reports. We identified patients who had endoscopy with intestinal biopsy during acute phase of NE. Histopathological, immunohistochemical and molecular analyses of the biopsies were performed. RESULTS: Thirteen patients underwent colonoscopy or gastroscopy for abdominal pain, diarrhea, nausea and vomiting during acute phase of NE. Immunohistochemistry (IHC revealed PUUV nucleocapsid antigen in 11 biopsies from 8 patients; 14 biopsies from 5 patients were negative for PUUV nucleocapsid antigen. IHC localized PUUV nucleocapsid antigen in endothelial cells of capillaries or larger vessels in the lamina propria. Rate of AKI was not higher and severity of AKI was not different in the PUUV-positive compared to the PUUV-negative group. All IHC positive biopsies were positive for PUUV RNA using RT-PCR. Phylogenetic reconstruction revealed clustering of all PUUV strains from this study with viruses previously detected from the South-West of Germany. Long-term outcome was favorable in both groups. CONCLUSIONS: In patients with NE, PUUV nucleocapsid antigen and PUUV RNA was detected frequently in the intestine. This finding could explain frequent GI-symptoms in NE patients, thus demonstration of a more generalized PUUV infection. The RT-PCR was an effective and sensitive method to detect PUUV RNA in FFPE tissues. Therefore, it can be used as a diagnostic and phylogenetic approach also for archival materials. AKI was not more often present in patients with PUUV-positive IHC. This last finding should be investigated in larger numbers of

  11. Impedance-Based Miniaturized Biosensor for Ultrasensitive and Fast Prostate-Specific Antigen Detection

    Directory of Open Access Journals (Sweden)

    Ganna Chornokur

    2011-01-01

    Full Text Available This paper reports the successful fabrication of an impedance-based miniaturized biosensor and its application for ultrasensitive Prostate-Specific Antigen (PSA detection in standard and real human plasma solution, spiked with different PSA concentrations. The sensor was fabricated using photolithographic techniques, while monoclonal antibodies specific to human PSA were used as primary capture antibodies. Electrochemical impedance spectroscopy (EIS was employed as a detection technique. The sensor exhibited a detection limit of 1 pg/ml for PSA with minimal nonspecific binding (NSB. This detection limit is an order of magnitude lower than commercial PSA ELISA assays available on the market. The sensor can be easily modified into an array for the detection of other biomolecules of interest, enabling accurate, ultrasensitive, and inexpensive point-of-care sensing technologies.

  12. Detection and monitoring of human bocavirus 1 infection by a new rapid antigen test

    Directory of Open Access Journals (Sweden)

    A.H.L. Bruning

    2016-05-01

    Full Text Available Clinically relevant diagnosis of human bocavirus 1 (HBoV1 is challenging, as the virus is frequently detected in asymptomatic patients, and cofindings with other respiratory viruses are common. The clinical value of current diagnostic methods, such as PCR, is therefore low, and alternative diagnostic strategies are needed. We describe for the first time the use of an antigen detection assay for the rapid identification of HBoV1 in a paediatric patient with respiratory tract infection symptoms. We estimate the duration of active HBoV1 infection to be 6 days.

  13. A simple assay for the detection of antibodies to endocrine islet cell surface antigens

    International Nuclear Information System (INIS)

    Contreas, G.; Madsen, O.D.; Vissing, H.; Lernmark, Aa.

    1986-01-01

    A simple and sensitive immunoradiometric assay for the detection of islet cell surface antibodies (CIRMA) has been developed. Live, transformed islet cells derived from a liver metastasis of a transplantable islet cell tumor were grown in removable microtiter wells and incubated with antibody. Cell-bound antibodies were quantitated using 125 I-labelled second antibodies. The assay was used to detect islet cell antibodies present in sera from non-diabetic and diabetic BB rats and proved to be particularly effective for screening hybridoma supernatants in order to identify monoclonal antibodies recognizing islet cell surface antigens. (Auth.)

  14. Molecular diversity of avian schistosomes in Danish freshwater snails

    DEFF Research Database (Denmark)

    Christiansen, Anne Ø.; Olsen, Annette; Buchmann, Kurt

    2016-01-01

    Avian schistosomes are widespread parasites of snails and waterfowl and may cause cercarial dermatitis (swimmer's itch) in humans, a disease that is frequently reported in European countries. These parasites are known to occur in Denmark, but here, we applied a new approach using molecular tools ...

  15. The schistosome oesophageal gland: initiator of blood processing.

    Directory of Open Access Journals (Sweden)

    Xiao-Hong Li

    Full Text Available BACKGROUND: Although the ultrastructure of the schistosome esophageal gland was described >35 years ago, its role in the processing of ingested blood has never been established. The current study was prompted by our identification of MEG-4.1 expression in the gland and the observation of erythrocyte uncoating in the posterior esophagus. METHODOLOGY/PRINCIPAL FINDINGS: The salient feature of the posterior esophagus, characterized by confocal and electron microscopy, is the enormous increase in membrane surface area provided by the plate-like extensions and basal invaginations of the lining syncytium, with unique crystalloid vesicles releasing their contents between the plates. The feeding process was shown by video microscopy to be divided into two phases, blood first accumulating in the anterior lumen before passing as a bolus to the posterior. There it streamed around a plug of material revealed by confocal microscopy as tethered leucocytes. These were present in far larger numbers than predicted from the volume of the lumen, and in varying states of damage and destruction. Intact erythrocytes were detected in the anterior esophagus but not observed thereafter, implying that their lysis occurred rapidly as they enter the posterior. Two further genes, MEGs 4.2 and 14, were shown to be expressed exclusively in the esophageal gland. Bioinformatics predicted that MEGs 4.1 and 4.2 possessed a common hydrophobic region with a shared motif, while antibodies to SjMEG-4.1 showed it was bound to leucocytes in the esophageal lumen. It was also predicted that MEGs 4.1 and 14 were heavily O-glycosylated and this was confirmed for the former by 2D-electrophoresis and Western blotting. CONCLUSIONS/SIGNIFICANCE: The esophageal gland and its products play a central role in the processing of ingested blood. The binding of host antibodies in the esophageal lumen shows that some constituents are antibody targets and could provide a new source of vaccine candidates.

  16. Development of a new in vivo kit for detection of prostate specific antigen in human serum using immunoradiometric assay method

    International Nuclear Information System (INIS)

    Babaei, M. H.; Behradkia, P.; Shafii, M.; Movla, M.; Forutan, H.; Najafi, R.

    2006-01-01

    Prostate is a leading site for the cancer incidence, accounted for 31.0% of new cancer cases in men. Prostate-specific antigen is widely used in the detection and monitoring of the prostate cancer. Currently, immunoassay is used to detect Prostate-specific antigen in human serum. This technique is based on the interaction between antibody and antigen. The varied immunoassay formats and equipment to run the assays allow the users to measure the analytes rapidly, with the flexibility to run a small or a large number of samples. Among different immunoassay methods, immunoradiometric assay is a more sensitive and valuable detection approach. This study has been made in 4 parts: (1) purification of Prostate-specific antigen from seminal fluid; (2) preparation of hybridoma cells which secrete monoclonal antibody (mAb) against Prostate-specific antigen , (3) selection of pair monoclonal antibody among those antibodies, and finally (4) design of an immunoradiometric assay kit and it's quality control . The results of this study were: (1) obtaining a huge amount of Prostate-specific antigen as semi-purified and purified, that is a valuable material for preparation of standard kits; (2) preparation of 8 kinds of monoclonal antibodies; (3) finding 4 pairs of monoclonal antibodies which react with different epitopes on Prostate-specific antigen molecule; and (4) preparation of immunoradiometric assay kit for measuring Prostate-specific antigen concentration in human serum

  17. [Comparison and evaluation of the Binax EIA and Biotest EIA urinary antigen kits for detection of Legionella pneumophila antigen in urine samples].

    Science.gov (United States)

    Rastawicki, Waldemar; Rokosz, Natalia; Jagielski, Marek

    2011-01-01

    The Binax and the Biotest urinary antigen kits for detection of L. pneumophila antigen were compared by testing of selected 67 urine samples obtained from EWGLI as reference samples in External Quality Assessment Scheme. Thirty nine were positive with the Binax kit (100% of sensitivity), and 33 were positive with the Biotest (84.6% of sensitivity). The test specificities were 100% for the both kits. It was concluded that the Binax kit was more suitable for the routine diagnosis of Legionella infections than the Biotest kit.

  18. Detection of hMPV antigen by EIA in clinical specimens.

    Science.gov (United States)

    Pancer, Katarzyna; Ciaćka, Agnieszka; Gut, Włodzimierz; Lipka, Bozena; Mierzejewska, Justyna; Milewska-Bobula, Bogumiła; Smorczewska-Kiljan, Anna; Jahnz-Rózyk, Karina; Litwińska, Bogumiła

    2011-01-01

    Human Metapneumovirus (hMPV) is one of the latest discovered viruses. It has been classified to Paramyxoviridae family. It is the second viral etiological agent, after RSV, which causes respiratory tract infections (RTI) in children, especially children below 5 years old. It is estimated that 5-25% of RTI in children is due to hMPV. In adults hMPV reinfections are bounded to upper respiratory tract infections. The aim of the study was to establish usefulness of ELISA test in detecting hMPV antigen and to analyze hMPV infection in connection to clinical diagnosis. 273 nasopharyngeal swabs from children (189 swabs) and adults (84 swabs) with respiratory tract infections collected from 2008 to 2010 were examined. Due to similarity of hMPV and RSV viruses and overlapping of their epidemic season rapid immunochromatographic test for RSV antigen detection was also performed in case of 120 samples, hMPV antigen was detected in 24.5% of all swabs (n = 67): in 0.0% probes in 2008, 29.0% in 2009 and 36.8% in first quarter of 2010. The highest rate ofhMPV infection was detected from summer of 2009 till the end of March 2010 (VIII-IX 2009 - 62.5%, X-XII 2009 - 44.1% and I-III 2010 -36.8%). We analyzed respiratory tract diseases reported in patients with hMPV infection. Infection due to hMPV was found in 26.5% of children and 24.0% of adults with recognized pneumonia, respectively in 28.4 and 17.6% of patients with bronchitis. Bronchiolitis was diagnosed in two children with hMPV. RSV and hMPV coinfections were confirmed in 15 out of 120 examined probes. Cross reaction pattern was excluded thanks to ELISA hMPV antigen test which was performed with suspension of RSV and thanks to statistical analysis. Coinfections were confirmed in 8% of pneumonia, 11% of bronchitis and 24.2% of the rest concomitant diagnoses. We found hMPV infection as the significant agent ofpneumonia not only in children but also in adults. ELISA hMPV antigen test can be used in diagnosis of etiological agent

  19. Anti-schistosomal intervention targets identified by lifecycle transcriptomic analyses.

    Directory of Open Access Journals (Sweden)

    Jennifer M Fitzpatrick

    2009-11-01

    Full Text Available Novel methods to identify anthelmintic drug and vaccine targets are urgently needed, especially for those parasite species currently being controlled by singular, often limited strategies. A clearer understanding of the transcriptional components underpinning helminth development will enable identification of exploitable molecules essential for successful parasite/host interactions. Towards this end, we present a combinatorial, bioinformatics-led approach, employing both statistical and network analyses of transcriptomic data, for identifying new immunoprophylactic and therapeutic lead targets to combat schistosomiasis.Utilisation of a Schistosoma mansoni oligonucleotide DNA microarray consisting of 37,632 elements enabled gene expression profiling from 15 distinct parasite lifecycle stages, spanning three unique ecological niches. Statistical approaches of data analysis revealed differential expression of 973 gene products that minimally describe the three major characteristics of schistosome development: asexual processes within intermediate snail hosts, sexual maturation within definitive vertebrate hosts and sexual dimorphism amongst adult male and female worms. Furthermore, we identified a group of 338 constitutively expressed schistosome gene products (including 41 transcripts sharing no sequence similarity outside the Platyhelminthes, which are likely to be essential for schistosome lifecycle progression. While highly informative, statistics-led bioinformatics mining of the transcriptional dataset has limitations, including the inability to identify higher order relationships between differentially expressed transcripts and lifecycle stages. Network analysis, coupled to Gene Ontology enrichment investigations, facilitated a re-examination of the dataset and identified 387 clusters (containing 12,132 gene products displaying novel examples of developmentally regulated classes (including 294 schistosomula and/or adult transcripts with no

  20. Dynamic imaging of experimental Leishmania donovani-induced hepatic granulomas detects Kupffer cell-restricted antigen presentation to antigen-specific CD8 T cells.

    Directory of Open Access Journals (Sweden)

    Lynette Beattie

    2010-03-01

    Full Text Available Kupffer cells (KCs represent the major phagocytic population within the liver and provide an intracellular niche for the survival of a number of important human pathogens. Although KCs have been extensively studied in vitro, little is known of their in vivo response to infection and their capacity to directly interact with antigen-specific CD8(+ T cells. Here, using a combination of approaches including whole mount and thin section confocal microscopy, adoptive cell transfer and intra-vital 2-photon microscopy, we demonstrate that KCs represent the only detectable population of mononuclear phagocytes within granulomas induced by Leishmania donovani infection that are capable of presenting parasite-derived peptide to effector CD8(+ T cells. This restriction of antigen presentation to KCs within the Leishmania granuloma has important implications for the identification of new candidate vaccine antigens and for the design of novel immuno-therapeutic interventions.

  1. Case of rhesus antigen weak D type 4.2. (DAR category detection

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    L. L. Golovkina

    2015-01-01

    Full Text Available Serological methods of Rhesus antigens identification in humans cannot identify D-antigen variants. In this article the serological characteristics of Rhesus antigen D weak type 4.2. (Category DAR are described.

  2. Glycomic Analysis of Life Stages of the Human Parasite Schistosoma mansoni Reveals Developmental Expression Profiles of Functional and Antigenic Glycan Motifs.

    Science.gov (United States)

    Smit, Cornelis H; van Diepen, Angela; Nguyen, D Linh; Wuhrer, Manfred; Hoffmann, Karl F; Deelder, André M; Hokke, Cornelis H

    2015-07-01

    Glycans present on glycoproteins and glycolipids of the major human parasite Schistosoma mansoni induce innate as well as adaptive immune responses in the host. To be able to study the molecular characteristics of schistosome infections it is therefore required to determine the expression profiles of glycans and antigenic glycan-motifs during a range of critical stages of the complex schistosome lifecycle. We performed a longitudinal profiling study covering schistosome glycosylation throughout worm- and egg-development using a mass spectrometry-based glycomics approach. Our study revealed that during worm development N-glycans with Galβ1-4(Fucα1-3)GlcNAc (LeX) and core-xylose motifs were rapidly lost after cercariae to schistosomula transformation, whereas GalNAcβ1-4GlcNAc (LDN)-motifs gradually became abundant and predominated in adult worms. LeX-motifs were present on glycolipids up to 2 weeks of schistosomula development, whereas glycolipids with mono- and multifucosylated LDN-motifs remained present up to the adult worm stage. In contrast, expression of complex O-glycans diminished to undetectable levels within days after transformation. During egg development, a rich diversity of N-glycans with fucosylated motifs was expressed, but with α3-core fucose and a high degree of multifucosylated antennae only in mature eggs and miracidia. N-glycan antennae were exclusively LDN-based in miracidia. O-glycans in the mature eggs were also diverse and contained LeX- and multifucosylated LDN, but none of these were associated with miracidia in which we detected only the Galβ1-3(Galβ1-6)GalNAc core glycan. Immature eggs also exhibited short O-glycan core structures only, suggesting that complex fucosylated O-glycans of schistosome eggs are derived primarily from glycoproteins produced by the subshell envelope in the developed egg. Lipid glycans with multifucosylated GlcNAc repeats were present throughout egg development, but with the longer highly fucosylated

  3. Lymphocyte proliferation to mycobacterial antigens is detectable across a spectrum of HIV-associated tuberculosis

    Directory of Open Access Journals (Sweden)

    Bakari Muhammad

    2009-02-01

    Full Text Available Abstract Background Identifying novel TB diagnostics is a major public health priority. We explored the diagnostic characteristics of antimycobacterial lymphocyte proliferation assays (LPA in HIV-infected subjects with latent or active TB. Methods HIV-infected subjects with bacille Calmette Guérin (BCG scars and CD4 counts ≥ 200 cells/mm3 entering a TB booster vaccine trial in Tanzania had baseline in vivo and in vitro immune tests performed: tuberculin skin tests (TST, LPA and five day assays of interferon gamma (IFN-γ release. Assay antigens were early secreted antigenic target 6 (ESAT-6, antigen 85 (Ag85, and Mycobacterium tuberculosis whole cell lysate (WCL. Subjects were screened for active TB at enrollment by history, exam, sputum smear and culture. We compared antimycobacterial immune responses between subjects with and without latent or active TB at enrollment. Results Among 1885 subjects screened, 635 had latent TB and 13 had active TB. Subjects with latent TB were more likely than subjects without TB to have LPA responses to ESAT-6 (13.2% vs. 5.5%, P Conclusion Lymphoproliferative responses to mycobacteria are detectable during HIV-associated active TB, and are less sensitive but more specific than TST. Trial registration ClinicalTrials.gov Identifier NCT00052195.

  4. Limitations of the radioimmunoprecipitation polyethylene glycol assay (RIPEGA) for detection of filarial antigens in serum

    International Nuclear Information System (INIS)

    Hamilton, R.G.; Alexander, E.; Adkinson, N.F.

    1984-01-01

    The performance of the radioimmunoprecipitation polyethylene glycol assay (RIPEGA) was examined for quantitation of filarial antigens (Brugia malayi and Dirofilaria immitis) in serum from infected human and animal hosts and non-infected controls. Multiple PEG concentrations were employed to determine the level of non-specific binding (NSB) in non-exposed human sera (NEHS) containing no filarial antigen. The NSB observed when 3 different 125 I-labelled IgG antibodies were added to 26 NEHS varied 3-fold and was correlated significantly with total serum IgM (r = 0.80, P 2 fragment of the 125 I-labelled antibody was used, but the correlation of NSB with total serum IgM remained significant (r = 0.57, P < 0.01). The presence of rheumatoid factor in NEHS sera also significantly increased NSB by an average of 3-fold. These effects eliminated the assay's ability to detect in sera from infected hosts filarial antigen the presence of which could be readily demonstrated by an immunoradiometric assay. The RIPEGA's precision (intra-assay coefficient of variation (CV) = 21% at 35% Bsub(max)) and reproducibility (inter-assay CV = 29% at 35% Bsub(max)) are less satisfactory than many alternative immunoassays. (Auth.)

  5. Immunization of cattle against Schistosome bovis (including pathophysiological studies on schistosome infection in bovines)

    International Nuclear Information System (INIS)

    Hussain, M.F.

    1978-12-01

    Bovine schistosomiasis caused by S. bovis constitutes a serious veterinary problem in the Sudan, yet very little is known about the epidemiology, pathogenesis and immunology of the disease. Over the past 5 years, work on these aspects has been conducted at Khartoum and several outlying areas of the White Nile Province in Sudan. In studies involving over 1,000 cattle, it was found that almost 100% of animals are infected by 2 years of age but that the prevalence falls to less than 60% over the following 7 years. There was also a marked reduction in the intensity of infection with increasing age, indicating the development of a high degree of acquired resistance. This was confirmed experimentally by challenging animals from an endemic area with massive numbers of cercariae. These animals completely resisted the challenge whereas animals never previously exposed either died or became moribund due to the severe haemorrhagic diarrhoea resulting from the passage of schistosome eggs through the gut wall. Attempts were made to vaccinate calves using irradiated organisms. These gave 70-80% protection against a challenge infection and this was sufficient to allow these animals to gain weight and remain clinically healthy. Animals not given the vaccine deteriorated. The efficacy of the vaccine was then tested under field conditions and found to give a high level of protection against S. bovis. These animals were also less susceptible to intercurrent infections

  6. Development of a PMMA Electrochemical Microfluidic Device for Carcinoembryonic Antigen Detection

    Science.gov (United States)

    Van Anh, Nguyen; Van Trung, Hoang; Tien, Bui Quang; Binh, Nguyen Hai; Ha, Cao Hong; Le Huy, Nguyen; Loc, Nguyen Thai; Thu, Vu Thi; Lam, Tran Dai

    2016-05-01

    In this study, a poly(methyl methacrylate) (PMMA) microfluidic device fabricated by an inexpensive CO2 laser etching system was developed for detection of carcino-embryonic antigens (CEA). The device was capable of working in continuous mode and was designed with the aid of numerical simulation. The detection of target CEA was based on immuno-assay via magnetic particles and electrochemical sensing. The as-prepared microfluidic can be used to detect CEA at the relatively low concentration of 150 pg mL-1. The device could be reused many times, since the capture and removal of magnetic particles in the assay could be manipulated by an external magnetic field. The proposed approach appears to be suitable for high-throughput and automated analysis of large biomolecules such as tumor markers and pathogens.

  7. Detection of a human intracisternal A-type retroviral particle antigenically related to HIV

    Science.gov (United States)

    Garry, R. F.; Fermin, C. D.; Hart, D. J.; Alexander, S. S.; Donehower, L. A.; Luo-Zhang, H.

    1990-01-01

    Sjogren's syndrome is an autoimmune disease that is characterized by dryness of the mouth and eyes. The loss of salivary and lacrimal gland function is accompanied by lymphocytic infiltration. Because similar symptoms and glandular pathology are observed in certain persons infected with human immunodeficiency virus (HIV), a search was initiated for a possible retroviral etiology in this syndrome. A human intracisternal A-type retroviral particle that is antigenically related to HIV was detected in lymphoblastoid cells exposed to homogenates of salivary tissue from patients with Sjogren's syndrome. Comparison of this retroviral particle to HIV indicates that they are distinguishable by several ultrastructural, physical, and enzymatic criteria.

  8. The diagnostic accuracy of carcinoembryonic antigen to detect colorectal cancer recurrence – A systematic review

    DEFF Research Database (Denmark)

    Sørensen, Caspar G; Karlsson, William K; Pommergaard, Hans-Christian

    2016-01-01

    INTRODUCTION: Carcinoembryonic Antigen (CEA) has been used as a tumor marker in the follow-up of colorectal cancer for more than 40 years. Controversy exists regarding its diagnostic applicability due to a relatively low sensitivity and a questionable effect on mortality. The aim of this review...... was to assess the diagnostic accuracy of CEA in detecting recurrence after intended curative surgery for primary colorectal cancer. METHODS: Systematic literature searches were performed in PubMed, EMBASE and Cochrane databases, and articles were chosen based on predefined inclusion criteria. Reference lists...

  9. Detection of viral antigens by solid phase radioimmunoassay on polyethylene film

    Energy Technology Data Exchange (ETDEWEB)

    Prokudina, E N; Semenova, N P; Zhdanov, V M

    1986-04-01

    Polyethylene film, without any pretreatment, may serve as a solid phase (SP) for RIA. Viral antigens (HBsAg, and influenza virus) are detected by SP-RIA on the film with a sensitivity of about 2-3 ng/ml or 40-60 pg/assay. The use of polyethylene film allows one to record RIA autographically. The use of micro amounts of reagents and specimens tested is an added advantage. No special equipment is necessary, the method is inexpensive, easy to perform and may be used for mass screening. (Auth.). 7 refs.; 4 figs.

  10. Antigen based detection of cystic echinococcosis in buffaloes using ELISA and Dot-EIA.

    Science.gov (United States)

    Sangaran, A; Bino Sundar, S T; Latha, Bhaskaran Ravi

    2017-03-01

    Cystic echinococcosis is caused by the larval stage of the dog tapeworm, Echinococcus granulosus . The disease is recognized as one of the world's major zoonoses affecting human beings and domestic animals apart from its economic and public health importance. Development of the cysts in the intermediate host such as buffaloes occurs in the lungs, liver and other organs. In this study, detection of circulating antigen in the diagnosis of cystic echinococcosis in buffaloes was done using enzyme linked immunosorbent assay and Dot-Enzyme immunoassay (Dot-EIA). The sensitivity and specificity were determined as 89 and 92 % respectively, whereas those of Dot-EIA were determined as 94 and 96 %.

  11. Use of Novel Recombinant Antigens in the Interferon Gamma Assay for Detection of Mycobacterium Avium Subsp. Paratuberculosis Infection in Cattle

    DEFF Research Database (Denmark)

    Mikkelsen, Heidi; Aagaard, Claus; Nielsen, Søren Saxmose

    2012-01-01

    of the study were to evaluate immunogenicity and specificity of 14 novel recombinant antigens for use in the IFN-γ assay and to assess the consistency of IFN-γ responses. The antigens used were 4 ESAT-6 family members, 4 latency proteins, 4 secreted proteins including Ag85B, 3 other antigens and PPDj......Early stage Mycobacterium avium subsp. paratuberculosis (MAP) infection can be detected by measuring antigen specific cell mediated immune responses by the interferon gamma (IFN-γ) assay. Available IFN-γ assay use purified protein derivate of Johnin (PPDj) leading to low specificity. The objectives...... of the infected and non-infected herds were significantly (Passay using PPDj did not correlate with the results using the novel antigens since 5 of the 17 animals that were positive to PPDj were...

  12. Hybrid Synthetic Receptors on MOSFET Devices for Detection of Prostate Specific Antigen in Human Plasma.

    Science.gov (United States)

    Tamboli, Vibha K; Bhalla, Nikhil; Jolly, Pawan; Bowen, Chris R; Taylor, John T; Bowen, Jenna L; Allender, Chris J; Estrela, Pedro

    2016-12-06

    The study reports the use of extended gate field-effect transistors (FET) for the label-free and sensitive detection of prostate cancer (PCa) biomarkers in human plasma. The approach integrates for the first time hybrid synthetic receptors comprising of highly selective aptamer-lined pockets (apta-MIP) with FETs for sensitive detection of prostate specific antigen (PSA) at clinically relevant concentrations. The hybrid synthetic receptors were constructed by immobilizing an aptamer-PSA complex on gold and subjecting it to 13 cycles of dopamine electropolymerization. The polymerization resulted in the creation of highly selective polymeric cavities that retained the ability to recognize PSA post removal of the protein. The hybrid synthetic receptors were subsequently used in an extended gate FET setup for electrochemical detection of PSA. The sensor was reported to have a limit of detection of 0.1 pg/mL with a linear detection range from 0.1 pg/mL to 1 ng/mL PSA. Detection of 1-10 pg/mL PSA was also achieved in diluted human plasma. The present apta-MIP sensor developed in conjunction with FET devices demonstrates the potential for clinical application of synthetic hybrid receptors for the detection of clinically relevant biomarkers in complex samples.

  13. A comparative study of blood smear, QBC and antigen detection for diagnosis of malaria.

    Science.gov (United States)

    Parija, S C; Dhodapkar, Rahul; Elangovan, Subashini; Chaya, D R

    2009-01-01

    Rapid diagnosis is prerequisite for effective treatment and reducing mortality and morbidity of malaria. This study was taken up to compare the efficacy of various methods available, i.e., thick and thin smear, quantitative buffy coat (QBC), plasmodium lactate dehydrogenase and aldolase in blood of patient. A total of 411 samples were collected from patients presenting with classic symptoms of malaria. For traditional microscopy; thick and thin smears were prepared and stained with Leishman's stain, taking thick smear as gold standard, thin smear had a sensitivity and specificity of 54.8% and 100%, respectively. QBC and antigen detection was done using commercially available kits; out of 411 samples, QBC and Malariagen were positive in 66 and 62 cases, with a sensitivity of 78% and 75%, respectively. Leishman's thick smear, although cost effective, is difficult to interpret for inexperienced microscopists; so if facilities are available, QBC should be used for routine diagnosis. In places where facilities are not available, rapid, simple and easy to interpret antigen detection test can be used despite low sensitivity.

  14. A comparative study of blood smear, QBC and antigen detection for diagnosis of malaria

    Directory of Open Access Journals (Sweden)

    Parija S

    2009-04-01

    Full Text Available Rapid diagnosis is prerequisite for effective treatment and reducing mortality and morbidity of malaria. This study was taken up to compare the efficacy of various methods available, i.e., thick and thin smear, quantitative buffy coat (QBC, plasmodium lactate dehydrogenase and aldolase in blood of patient. A total of 411 samples were collected from patients presenting with classic symptoms of malaria. For traditional microscopy; thick and thin smears were prepared and stained with Leishman′s stain, taking thick smear as gold standard, thin smear had a sensitivity and specificity of 54.8% and 100%, respectively. QBC and antigen detection was done using commercially available kits; out of 411 samples, QBC and Malariagen were positive in 66 and 62 cases, with a sensitivity of 78% and 75%, respectively. Leishman′s thick smear, although cost effective, is difficult to interpret for inexperienced microscopists; so if facilities are available, QBC should be used for routine diagnosis. In places where facilities are not available, rapid, simple and easy to interpret antigen detection test can be used despite low sensitivity.

  15. Detection of carcinoembryonic antigen using functional magnetic and fluorescent nanoparticles in magnetic separators

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, H. Y., E-mail: annetsai@csmu.edu.tw [Chung Shan Medical University, Department of Applied Chemistry (China); Chang, C. Y.; Li, Y. C.; Chu, W. C.; Viswanathan, K.; Bor Fuh, C., E-mail: cbfuh@ncnu.edu.tw [National Chi Nan University, Department of Applied Chemistry (China)

    2011-06-15

    We combined a sandwich immunoassay, anti-CEA/CEA/anti-CEA, with functional magnetic ({approx}80 nm) and fluorescent ({approx}180 nm) nanoparticles in magnetic separators to demonstrate a detection method for carcinoembryonic antigen (CEA). Determination of CEA in serum can be used in clinical diagnosis and monitoring of tumor-related diseases. The CEA concentrations in samples were deduced and determined based on the reference plot using the measured fluorescent intensity of sandwich nanoparticles from the sample. The linear range of CEA detection was from 18 ng/mL to 1.8 pg/mL. The detection limit of CEA was 1.8 pg/mL. In comparison with most other detection methods, this method had advantages of lower detection limit and wider linear range. The recovery was higher than 94%. The CEA concentrations of two serum samples were determined to be 9.0 and 55 ng/mL, which differed by 6.7% (9.6 ng/mL) and 9.1% (50 ng/mL) from the measurements of enzyme-linked immunosorbent assay (ELISA), respectively. The analysis time can be reduced to one third of ELISA. This method has good potential for other biomarker detections and biochemical applications.

  16. An improved haemolytic plaque assay for the detection of cells secreting antibody to bacterial antigens

    DEFF Research Database (Denmark)

    Barington, T; Heilmann, C

    1992-01-01

    Recent advances in the development of conjugate polysaccharide vaccines for human use have stimulated interest in the use of assays detecting antibody-secreting cells (AbSC) with specificity for bacterial antigens. Here we present improved haemolytic plaque-forming cell (PFC) assays detecting Ab......SC with specificity for tetanus and diphtheria toxoid as well as for Haemophilus influenzae type b and pneumococcal capsular polysaccharides. These assays were found to be less time consuming, more economical and yielded 1.9-3.4-fold higher plaque numbers than traditional Jerne-type PFC assays. In the case of anti......-polysaccharide antibodies aggregation of secreted monomeric antibody (IgG) is critical for plaque formation and increases the avidity of binding to target cells....

  17. Detection of hepatitis B surface antigen by solid phase radioimmunoassay and immunometric assay (using enhanced luminescence)

    International Nuclear Information System (INIS)

    Nicholson, S.; Efandis, T.; Gust, I.

    1991-01-01

    A study was performed to assess the sensitivity and specificity of the amerlite monoclonal immunoassay for detection of hepatitis B surface antigen (HBsAG) by comparison with the Abbott Ausria II radioimmunoassay (RI). Serial bleeds from 34 patients with acute or chronic hepatitis B were tested by both assays. The Abbott Ausria II assay detected HBsAG longer than the Amersham Amerlite assay on two occasions and earlier on one occasion. Twelve patients with low HBsAg positive results (confirmed by Ausria II) were tested by the Amerlite assay, four were repeatably positive, five repeatably negative and three gave borderline results (which on repeat testing were negative). A similar trend was seen when a panel of sera containing known concentrations of HBsAG was tested. Replicate testing of 10 specimens eight times showed very good reproducibility by the Amerlite assay. Overall, the specificity of both assays was comparable, however differences in sensitivity were observed. 3 tabs

  18. Preparation of miniantibodies to Azospirillum brasilense Sp245 surface antigens and their use for bacterial detection.

    Science.gov (United States)

    Dykman, Lev A; Staroverov, Sergei A; Guliy, Olga I; Ignatov, Oleg V; Fomin, Alexander S; Vidyasheva, Irina V; Karavaeva, Olga A; Bunin, Viktor D; Burygin, Gennady L

    2012-01-01

    This article reports the first preparation of miniantibodies to Azospirillum brasilense Sp245 surface antigens by using a combinatorial phage library of sheep antibodies. The prepared phage antibodies were used for the first time for lipopolysaccharide and flagellin detection by dot assay, electro-optical analysis of cell suspensions, and transmission electron microscopy. Interaction of A. brasilense Sp245 with antilipopolysaccharide and antiflagellin phage-displayed miniantibodies caused the magnitude of the electro-optical signal to change considerably. The electro-optical results were in good agreement with the electron microscopic data. This is the first reported possibility of employing phage-displayed miniantibodies in bacterial detection aided by electro-optical analysis of cell suspensions.

  19. Enzyme linked immunosorbent assay for detecting antibody to Trichomonas vaginalis: use of whole cells and aqueous extract as antigen.

    OpenAIRE

    Alderete, J F

    1984-01-01

    An enzyme linked immunosorbent assay (ELISA) for detecting antibody to antigenic Trichomonas vaginalis macromolecules has been identified using whole cells or an aqueous protein extract as antigen. The test was developed under optimum conditions using serum samples from experimental animals. The sensitivity of the ELISA was equal to or greater than that obtained by radioimmunoprecipitation and electrophoresis-fluorography techniques. The ELISA was capable of assessing antibody responses durin...

  20. Carcinoma-associated antigens

    International Nuclear Information System (INIS)

    Bartorelli, A.; Accinni, R.

    1981-01-01

    This invention relates to novel antigens associated with breast carcinoma, anti-sera specific to said antigens, 125 I-labeled forms of said antigens and methods of detecting said antigens in serum or plasma. The invention also relates to a diagnostic kit containing standardised antigens or antisera or marked forms thereof for the detection of said antigens in human blood, serum or plasma. (author)

  1. Impact of the rapid antigen detection test in diagnosis and treatment of acute pharyngotonsillitis in a pediatric emergency room.

    Science.gov (United States)

    Cardoso, Débora Morais; Gilio, Alfredo Elias; Hsin, Shieh Huei; Machado, Beatriz Marcondes; de Paulis, Milena; Lotufo, João Paulo B; Martinez, Marina Baquerizo; Grisi, Sandra Josefina E

    2013-01-01

    To evaluate the impact of the routine use of rapid antigen detection test in the diagnosis and treatment of acute pharyngotonsillitis in children. This is a prospective and observational study, with a protocol compliance design established at the Emergency Unit of the University Hospital of Universidade de São Paulo for the care of children and adolescents diagnosed with acute pharyngitis. 650 children and adolescents were enrolled. Based on clinical findings, antibiotics would be prescribed for 389 patients (59.8%); using the rapid antigen detection test, they were prescribed for 286 patients (44.0%). Among the 261 children who would not have received antibiotics based on the clinical evaluation, 111 (42.5%) had positive rapid antigen detection test. The diagnosis based only on clinical evaluation showed 61.1% sensitivity, 47.7% specificity, 44.9% positive predictive value, and 57.5% negative predictive value. The clinical diagnosis of streptococcal pharyngotonsillitis had low sensitivity and specificity. The routine use of rapid antigen detection test led to the reduction of antibiotic use and the identification of a risk group for complications of streptococcal infection, since 42.5% positive rapid antigen detection test patients would not have received antibiotics based only on clinical diagnosis.

  2. Screen Printed Carbon Electrode Based Electrochemical Immunosensor for the Detection of Dengue NS1 Antigen

    Directory of Open Access Journals (Sweden)

    Om Parkash

    2014-11-01

    Full Text Available An electrochemical immunosensor modified with the streptavidin/biotin system on screen printed carbon electrodes (SPCEs for the detection of the dengue NS1 antigen was developed in this study. Monoclonal anti-NS1 capture antibody was immobilized on streptavidin-modified SPCEs to increase the sensitivity of the assay. Subsequently, a direct sandwich enzyme linked immunosorbent assay (ELISA format was developed and optimized. An anti-NS1 detection antibody conjugated with horseradish peroxidase enzyme (HRP and 3,3,5,5'-tetramethybezidine dihydrochloride (TMB/H2O2 was used as an enzyme mediator. Electrochemical detection was conducted using the chronoamperometric technique, and electrochemical responses were generated at −200 mV reduction potential. The calibration curve of the immunosensor showed a linear response between 0.5 µg/mL and 2 µg/mL and a detection limit of 0.03 µg/mL. Incorporation of a streptavidin/biotin system resulted in a well-oriented antibody immobilization of the capture antibody and consequently enhanced the sensitivity of the assay. In conclusion, this immunosensor is a promising technology for the rapid and convenient detection of acute dengue infection in real serum samples.

  3. A novel approach for reliable detection of cathepsin S activities in mouse antigen presenting cells.

    Science.gov (United States)

    Steimle, Alex; Kalbacher, Hubert; Maurer, Andreas; Beifuss, Brigitte; Bender, Annika; Schäfer, Andrea; Müller, Ricarda; Autenrieth, Ingo B; Frick, Julia-Stefanie

    2016-05-01

    Cathepsin S (CTSS) is a eukaryotic protease mostly expressed in professional antigen presenting cells (APCs). Since CTSS activity regulation plays a role in the pathogenesis of various autoimmune diseases like multiple sclerosis, atherosclerosis, Sjögren's syndrome and psoriasis as well as in cancer progression, there is an ongoing interest in the reliable detection of cathepsin S activity. Various applications have been invented for specific detection of this enzyme. However, most of them have only been shown to be suitable for human samples, do not deliver quantitative results or the experimental procedure requires technical equipment that is not commonly available in a standard laboratory. We have tested a fluorogen substrate, Mca-GRWPPMGLPWE-Lys(Dnp)-DArg-NH2, that has been described to specifically detect CTSS activities in human APCs for its potential use for mouse samples. We have modified the protocol and thereby offer a cheap, easy, reproducible and quick activity assay to detect CTSS activities in mouse APCs. Since most of basic research on CTSS is performed in mice, this method closes a gap and offers a possibility for reliable and quantitative CTSS activity detection that can be performed in almost every laboratory. Copyright © 2016. Published by Elsevier B.V.

  4. Fluorescence-based endoscopic imaging of Thomsen-Friedenreich antigen to improve early detection of colorectal cancer.

    Science.gov (United States)

    Sakuma, Shinji; Yu, James Y H; Quang, Timothy; Hiwatari, Ken-Ichiro; Kumagai, Hironori; Kao, Stephanie; Holt, Alex; Erskind, Jalysa; McClure, Richard; Siuta, Michael; Kitamura, Tokio; Tobita, Etsuo; Koike, Seiji; Wilson, Kevin; Richards-Kortum, Rebecca; Liu, Eric; Washington, Kay; Omary, Reed; Gore, John C; Pham, Wellington

    2015-03-01

    Thomsen-Friedenreich (TF) antigen belongs to the mucin-type tumor-associated carbohydrate antigen. Notably, TF antigen is overexpressed in colorectal cancer (CRC) but is rarely expressed in normal colonic tissue. Increased TF antigen expression is associated with tumor invasion and metastasis. In this study, we sought to validate a novel nanobeacon for imaging TF-associated CRC in a preclinical animal model. We developed and characterized the nanobeacon for use with fluorescence colonoscopy. In vivo imaging was performed on an orthotopic rat model of CRC. Both white light and fluorescence colonoscopy methods were utilized to establish the ratio-imaging index for the probe. The nanobeacon exhibited specificity for TF-associated cancer. Fluorescence colonoscopy using the probe can detect lesions at the stage which is not readily confirmed by conventional visualization methods. Further, the probe can report the dynamic change of TF expression as tumor regresses during chemotherapy. Data from this study suggests that fluorescence colonoscopy can improve early CRC detection. Supplemented by the established ratio-imaging index, the probe can be used not only for early detection, but also for reporting tumor response during chemotherapy. Furthermore, since the data obtained through in vivo imaging confirmed that the probe was not absorbed by the colonic mucosa, no registered toxicity is associated with this nanobeacon. Taken together, these data demonstrate the potential of this novel probe for imaging TF antigen as a biomarker for the early detection and prediction of the progression of CRC at the molecular level. © 2014 UICC.

  5. On the importance of controlling film architecture in detecting prostate specific antigen

    Science.gov (United States)

    Graça, Juliana Santos; Miyazaki, Celina Massumi; Shimizu, Flavio Makoto; Volpati, Diogo; Mejía-Salazar, J. R.; Oliveira, Osvaldo N., Jr.; Ferreira, Marystela

    2018-03-01

    Immunosensors made with nanostructured films are promising for detecting cancer biomarkers, even at early stages of the disease, but this requires control of film architecture to preserve the biological activity of immobilized antibodies. In this study, we used electrochemical impedance spectroscopy (EIS) to detect Prostate Specific Antigen (PSA) with immunosensors produced with layer-by-layer (LbL) films containing anti-PSA antibodies in two distinct film architectures. The antibodies were either adsorbed from solutions in which they were free, or from solutions where they were incorporated into liposomes of dipalmitoyl phosphatidyl glycerol (DPPG). Incorporation into DPPG liposomes was confirmed with surface plasmon resonance experiments, while the importance of electrostatic interactions on the electrical response was highlighted using the Finite Difference Time-Domain Method (FDTD). The sensitivity of both architectures was sufficient to detect the threshold value to diagnose prostate cancer (ca. 4 ng mL-1). In contrast to expectation, the sensor with the antibodies incorporated into DPPG liposomes had lower sensitivity, though the range of concentrations amenable to detection increased, according to the fitting of the EIS data using the Langmuir-Freundlich adsorption model. The performance of the two film architectures was compared qualitatively by plotting the data with a multidimensional projection technique, which constitutes a generic approach for optimizing immunosensors and other types of sensors.

  6. Gold nanoparticle-based low limit of detection Love wave biosensor for carcinoembryonic antigens.

    Science.gov (United States)

    Li, Shuangming; Wan, Ying; Su, Yan; Fan, Chunhai; Bhethanabotla, Venkat R

    2017-09-15

    In this work, a Love wave biosensing platform is described for detecting cancer-related biomarker carcinoembryonic antigen (CEA). An ST 90°-X quartz Love wave device with a layer of SiO 2 waveguide was combined with gold nanoparticles (Au NPs) to amplify the mass loading effect of the acoustic wave sensor to achieve a limit of detection of 37pg/mL. The strategy involves modifying the Au NPs with anti-CEA antibody conjugates to form nanoprobes in a sandwich immunoassay. The unamplified detection limit of the Love wave biosensor is 9.4ng/mL. This 2-3 order of magnitude reduction in the limit of detection brings the SAW platform into the range useful for clinical diagnosis. Measurement electronics and microfluidics are easily constructed for acoustic wave biosensors, such as the Love wave device described here, allowing for robust platforms for point of care applications for cancer biomarkers in general. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Immunodiagnosis of fascioliasis using sandwich enzyme-linked immunosorbent assay for detection of Fasciola gigantica paramyosin antigen

    Science.gov (United States)

    Abou-Elhakam, Hany Mohamed Adel; Bauomy, Ibraheem Rabia; El Deeb, Somaya Osman; El Amir, Azza Mohamed

    2013-01-01

    Background: Many immunological techniques have been developed over years using the different Fasciola antigens for diagnosis of parasitic infection and to replace the parasitological techniques, which are time consuming and usually lack sensitivity and reproducibility. Materials and Methods: In this study, Fasciola gigantica paramyosin (Pmy) antigen was early detected in cattle sera using sandwich enzyme-linked immunosorbent assay (ELISA), to evaluate the Pmy antigen performance in diagnosis. This work was conducted on 135 cattle blood samples, which were classified according to parasitological investigation into, healthy control (30), fascioliasis (75), and other parasites (30) groups. Results: The sensitivity of Sandwich ELISA was 97.33%, and the specificity was 95%, in comparison with parasitological examination, which recorded 66.66% sensitivity and 100% specificity, respectively. Conclusions: It was clear that the native F. gigantica Pmy is considered as a powerful antigen in early immunodiagnosis of fascioliasis, using a highly sensitive and specific sandwich ELISA technique. PMID:23961441

  8. A comparison of labelled antibody methods for the detection of virus antigens in cell monolayers

    International Nuclear Information System (INIS)

    Oram, J.D.; Crooks, A.J.

    1979-01-01

    A number of labelled antibody methods have been applied to the detection of Semliki Forest virus antigens after replication of the virus in monolayers of host cells in multi-well polystyrene plates. The importance of several reaction variables has been investigated and the sensitivity of the methods compared for different periods of virus replication. Direct assays with radio-labelled antibody (RLA) and indirect assays peroxidase-antiperoxidase complexes (PAP) were equally sensitive. Direct and indirect assays using enzyme-linked antibodies (ELA) were slightly less sensitive than the direct RLA and PAP methods but were more sensitive than the indirect RLA or fluorescent antibody (FLA) methods. Direct assays using ELA were more rapid and easier to perform than the other assay methods. (Auth.)

  9. Large-scale detection of antigen-specific T cells using peptide-MHC-I multimers labeled with DNA barcodes

    DEFF Research Database (Denmark)

    Bentzen, Amalie Kai; Marquard, Andrea Marion; Lyngaa, Rikke Birgitte

    2016-01-01

    -major histocompatibility complex (MHC) multimers labeled with individual DNA barcodes to screen >1,000 peptide specificities in a single sample, and detect low-frequency CD8 T cells specific for virus- or cancer-restricted antigens. When analyzing T-cell recognition of shared melanoma antigens before and after adoptive...... cell therapy in melanoma patients, we observe a greater number of melanoma-specific T-cell populations compared with cytometry-based approaches. Furthermore, we detect neoepitope-specific T cells in tumor-infiltrating lymphocytes and peripheral blood from patients with non-small cell lung cancer...

  10. Detection of Hepatitis B Virus Antigens in Paraffin-embedded Liver Specimens from the Amazon Region, Brazil

    Directory of Open Access Journals (Sweden)

    Simonetti SRR

    2002-01-01

    Full Text Available Hepatic viscerotomy of paraffin-preserved old specimens, collected in the period from 1934 to 1967, were analyzed by immunohistochemical assays to detect hepatitis B, hepatitis D, dengue and yellow fever virus antigens. The material belongs to the Yellow Fever Collection, Department of Pathology, Instituto Oswaldo Cruz, Rio de Janeiro, Brazil and the cases were diagnosed at that time according to clinical aspects and histopathological findings reporting viral hepatitis, yellow fever, focal necrosis and hepatic atrophy. From the 79 specimens, 69 were collected at the Labrea Region and the other 10 in different other localities in the Amazon Region. The five micra thick histological slices were analyzed for the presence of hepatitis B surface antigen (HBsAg and hepatitis B core antigen (HBcAg by immunoperoxidase technique. An immunofluorescence assay was applied to the detection of hepatitis D, yellow fever and dengue virus antigens. Nine (11.4% histological samples were HBsAg reactive and 5 (6.3% were HBcAg reactive. The oldest reactive sample was from 1934. Viral antigens related to the other pathologies were not detected in this study. Our results confirm that the methodology described may be used to elucidate the aetiology of hepatitis diseases even after a long time of conservation of the specimens.

  11. Development of a double-antibody radioimmunoassay for detecting ovarian tumor-associated antigen fraction OCA in plasma

    International Nuclear Information System (INIS)

    Knauf, S.; Urbach, G.I.

    1978-01-01

    Ovarian tumor-associated antigen isolated from human tumor tissue was shown to have a different mobility from that of carcinoembryonic antigen (CEA) in both acrylamide gel electrophoresis and immunoelectrophoresis in agarose. The ovarian tumor antigen is composed of six species with different electrophoretic mobility in acrylamide gel electrophoresis. Three of these species were detected in Sephadex G-100 ovarian fraction OCA (from the void volume peak) and the other three species of lower apparent molecular weight were detected in fraction OCD (from the second peak). Fractions OCA and OCD did not share common antigenic determinants as determined by immunodiffusion. CEA was shown to share antigenic determinants with both OCA and OCD. A double-antibody radioimmunoassay capable of detecting nanogram quantities of plasma OCA was developed. In a preliminary study of ovarian cancer patients, OCA appeared to be a more sensitive marker for ovarian cancer than CEA. There was virtually no correlation (r 2 = 0.1) between OCA and CEA levels in these patients, as determined by radioimmunoassay

  12. Solid phase radioimmunoassay for detection of malaria antigen. Comparison of monoclonal and polyclonal antibodies

    International Nuclear Information System (INIS)

    Khusmith, S.; Tharavanij, S.; Patarapotikul, J.; Kasemsuth, R.; Bunnag, D.

    1986-01-01

    A solid phase competitive binding radioimmunoassay (RIA) was developed for the detection of Plasmodium falciparum in infected blood. A suspension of NP40 treated red blood cells was mixed with labelled antimalarial IgG, incubated and then added to malarial antigen coated microtitre plate. Antimalarial IgGs were purified either from high titre sera from individuals living in a malaria endemic area in Thailand or from a locally produced monoclonal antibody (MAB) which showed a bright generalized immunofluorescent staining pattern against all blood stages of P. falciparum, including gametocytes. This MAB reacted with 27 of 31 P. falciparum isolates from Thailand. Using dilution of red blood cells from in vitro cultures of P. falciparum, the test was found to detect parasites at levels equivalent to 13 and 2.2 parasites/10 6 red blood cells with labelled polyclonal IgG (PIgG) and labelled monoclonal IgG (MIgG), respectively. No false positive results were obtained among samples from non-malarial subjects. Of the samples that gave negative results upon microscopic examination, 50 and 35% were still positive with RIA using MIgG and PIgG, respectively. There was a correlation between RIA and the number of parasites, especially when MIgG was used. The results indicate that the IgG fraction of sera from individuals with natural acquired immunity to malaria showed a lower degree of sensitivity in parasite detection than the IgG from monoclonal antibody. (author)

  13. Detection of target staphylococcal enterotoxin B antigen in orange juice and popular carbonated beverages using antibody-dependent antigen-capture assays.

    Science.gov (United States)

    Principato, MaryAnn; Njoroge, Joyce M; Perlloni, Andrei; O' Donnell, Michael; Boyle, Thomas; Jones, Robert L

    2010-10-01

    There is a critical need for qualitative and quantitative methodologies that provide the rapid and accurate detection of food contaminants in complex food matrices. However, the sensitivity of the assay can be affected when antigen-capture is applied to certain foods or beverages that are extremely acidic. This study was undertaken to assess the effects of orange juice and popular carbonated soft drink upon the fidelity of antibody-based antigen-capture assays and to develop simple approaches that could rescue assay performance without the introduction of additional or extensive extraction procedures. We examined the effects of orange juice and a variety of popular carbonated soft drink beverages upon a quantitative Interleukin-2 (IL-2) enzyme-linked immunosorbent assay (ELISA) assay system and a lateral flow device (LFD) adapted for the detection of staphylococcal enterotoxin B (SEB) in foods. Alterations in the performance and sensitivity of the assay were directly attributable to the food matrix, and alterations in pH were especially critical. The results demonstrate that approaches such as an alteration of pH and the use of milk as a blocking agent, either singly or in combination, will partially rescue ELISA performance. The same approaches permit lateral flow to efficiently detect antigen. Practical Application: The authors present ways to rescue an ELISA assay compromised by acidity in beverages and show that either the alteration of pH, or the use of milk as a blocking agent are not always capable of restoring the assay to its intended efficiency. However, the same methods, when employed with lateral flow technology, are rapid and extremely successful.

  14. Diagnosis of Fasciola gigantica infection in cattle using capture-ELISA assay for detecting antigen in faeces

    Directory of Open Access Journals (Sweden)

    Sarwitri Endah Estuningsih

    2006-10-01

    Full Text Available Capture-ELISA assay is a diagnosis for antigen detection in the serum or faeces using polyclonal or monoclonal antibodies. The purpose of this study was to determine the sensitivity and specificity of capture-ELISA assay using polyclonal antibody for diagnosing Fasciola gigantica infection in cattle by detecting antigen in the faeces. In this study, faecal samples and livers were collected from 141 cattle slaughtered in the abattoir in Jakarta. From each animal, liver was processed for liver flukes count and the corresponding faecal sample was analysed for coproantigen. The result of capture-ELISA assay for antigen detection showed that from 85 cattle infected with Fasciola gigantica, 83 had OD > 0.52 (range from 0.52-1.39 and 2 cattle had OD < 0.52 (range from 0.17-0.51. The sensitivity and specificity of the assay were 97.6% and 92.8% respectively. The assay also able to detect 50 ng/ml of antigen in faecal supernatant. It suggests that this assay will have the advantage over the other methods on its ability to detect the active infection. Collection of faeces, rather than serum, will allow a more cost-effective and adaptable method.

  15. Schistosome serine protease inhibitors: parasite defense or homeostasis?

    Directory of Open Access Journals (Sweden)

    Landys A. Lopez Quezada

    2011-06-01

    Full Text Available Serpins are a structurally conserved family of macromolecular inhibitors found in numerous biological systems. The completion and annotation of the genomes of Schistosoma mansoni and Schistosoma japonicum has enabled the identification by phylogenetic analysis of two major serpin clades. S. mansoni shows a greater multiplicity of serpin genes, perhaps reflecting adaptation to infection of a human host. Putative targets of schistosome serpins can be predicted from the sequence of the reactive center loop (RCL. Schistosome serpins may play important roles in both post-translational regulation of schistosome-derived proteases, as well as parasite defense mechanisms against the action of host proteases.Serpinas são uma família de inibidores macromoleculares estruturalmente conservados encontrados em inúmeros sistemas biológicos. O término e a anotação dos genomas de Schistosoma mansoni e de Schistosoma japonicum permitiram a identificação por análise filogenética de dois principais clados de serpinas. S. mansoni mostra uma multiplicidade maior de genes de serpinas, talvez refletindo uma adaptação à infecção de um hospedeiro humano. Alvos putativos das serpinas de esquistossomos podem ser preditos a partir da sequência do "loop" do centro reativo. Serpinas de esquistossomos podem ter importantes papeis tanto na regulação pós-traducional de proteases derivadas do esquistossoma, quanto nos mecanismos de defesa contra a ação de proteases do hospedeiro.

  16. Evaluation of a newly designed sandwich enzyme linked immunosorbent assay for the detection of hydatid antigen in serum, urine and cyst fluid for diagnosis of cystic echinococcosis.

    Science.gov (United States)

    Chaya, Dr; Parija, Subhash Chandra

    2013-07-01

    Cystic echinococcosis (CE) is a zoonotic disease of humans with variable clinical manifestations. Imaging and immunological methods are currently the mainstay of diagnosis of this disease. Although the immunological tests for detection of anti-echinococcal antibodies have several disadvantages, they are widely being used. Antigen is far more superior than antibody detection test as they can provide a specific parasitic diagnosis. A sandwich enzyme linked immunosorbent assay (ELISA) was designed using antibodies to 24 kDa urinary hydatid antigen for the detection of hydatid antigens in urine, serum and cyst fluid specimens. The performance of this novel test was compared with that of other hydatid antibody detection ELISA and enzyme immune transfer blot (EITB) using radiological and surgical confirmation as the gold standard. The antigen detection ELISA showed 100% sensitivity and specificity when tested with cyst fluid. On testing urine and serum, the antigen detection ELISA was found to be more specific than antibody detection ELISA. EITB was found to be the most sensitive and specific test. ELISA using polyclonal antibodies against 24 kDa urinary hydatid protein was moderately sensitive to detect hydatid antigen in serum and urine. Hence polyclonal antibodies to 24 kDa urinary hydatid antigen can be used as an alternative source of antibody to detect hydatid antigen in serum, urine and cyst fluid. In the present study, EITB was found to be highly specific test for detection of hydatid antibodiesin serum. 24 kDa protein was found to be specific and of diagnostic value in CE.

  17. Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool

    Directory of Open Access Journals (Sweden)

    Flávio da Silva Mesquita

    2017-05-01

    Full Text Available Objective: The aim of this study was to evaluate the QuickVue® RSV Test Kit (QUIDEL Corp, CA, USA as a screening tool for respiratory syncytial virus in children with acute respiratory disease in comparison with the indirect immunofluorescence assay as gold standard. In Brazil, rapid antigen detection tests for respiratory syncytial virus are not routinely utilized as a diagnostic tool, except for the diagnosis of dengue and influenza. Methods: The authors retrospectively analyzed 486 nasopharyngeal aspirate samples from children under age 5 with acute respiratory infection, between December 2013 and August 2014, the samples were analyzed by indirect immunofluorescence assay and QuickVue® RSV Test kit. Samples with discordant results were analyzed by real time PCR and nucleotide sequencing. Results: From 313 positive samples by immunofluorescence assays, 282 (90% were also positive by the rapid antigen detection test, two were positive only by rapid antigen detection test, 33 were positive only by immunofluorescence assays, and 171 were positive by both methods. The 35 samples with discordant results were analyzed by real time PCR; the two samples positive only by rapid antigen detection test and the five positive only by immunofluorescence assays were also positive by real time PCR. There was no relation between the negativity by QuickVue® RSV Test and viral load or specific strain. The QuickVue® RSV Test showed sensitivity of 90%, specificity of 98.8%, predictive positive value of 99.3%, and negative predictive value of 94.6%, with accuracy of 93.2% and agreement κ index of 0.85 in comparison to immunofluorescence assay. Conclusions: This study demonstrated that the QuickVue® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics. Resumo: Objetivo: Avaliar o teste QuickVue® RSV Test Kit (QUIDEL Corp, CA, EUA para o diagn

  18. Utility of galactomannan antigen detection in bronchoalveolar lavage fluid in immunocompromised patients.

    Science.gov (United States)

    Brownback, Kyle R; Pitts, Lucas R; Simpson, Steven Q

    2013-09-01

    Diagnosis of invasive pulmonary aspergillosis (IPA) is a challenging process in immunocompromised patients. Galactomannan (GM) antigen detection in bronchoalveolar lavage (BAL) fluid is a method to detect IPA with improved sensitivity over conventional studies. We sought to determine the diagnostic yield of BAL GM assay in a diverse population of immunocompromised patients. A retrospective review of 150 fiberoptic bronchoscopy (FOB) with BAL for newly diagnosed pulmonary infiltrate in immunocompromised patients was performed. Patient information, procedural details and laboratory studies were collected. BAL and serum samples were evaluated for GM using enzyme-linked immunoassay. Of 150 separate FOB with BAL, BAL GM was obtained in 143 samples. There were 31 positive BAL GM assays. In those 31 positive tests, 13 were confirmed as IPA, giving a positive predictive value of 41.9%. There was one false negative BAL GM. Of the 18 false positive BAL GM, 4 were receiving piperacillin-tazobactam and 11 were receiving an alternative beta-lactam antibiotic. BAL GM assay shows excellent sensitivity for diagnosing IPA. There was a significant number of false positive BAL GM assays and several of those patients were receiving beta-lactam antibiotics at the time of bronchoscopy. © 2013 Blackwell Verlag GmbH.

  19. Prostate Cancer Detection and Prognosis: From Prostate Specific Antigen (PSA) to Exosomal Biomarkers.

    Science.gov (United States)

    Filella, Xavier; Foj, Laura

    2016-10-26

    Prostate specific antigen (PSA) remains the most used biomarker in the management of early prostate cancer (PCa), in spite of the problems related to false positive results and overdiagnosis. New biomarkers have been proposed in recent years with the aim of increasing specificity and distinguishing aggressive from non-aggressive PCa. The emerging role of the prostate health index and the 4Kscore is reviewed in this article. Both are blood-based tests related to the aggressiveness of the tumor, which provide the risk of suffering PCa and avoiding negative biopsies. Furthermore, the use of urine has emerged as a non-invasive way to identify new biomarkers in recent years, including the PCA3 and TMPRSS2:ERG fusion gene. Available results about the PCA3 score showed its usefulness to decide the repetition of biopsy in patients with a previous negative result, although its relationship with the aggressiveness of the tumor is controversial. More recently, aberrant microRNA expression in PCa has been reported by different authors. Preliminary results suggest the utility of circulating and urinary microRNAs in the detection and prognosis of PCa. Although several of these new biomarkers have been recommended by different guidelines, large prospective and comparative studies are necessary to establish their value in PCa detection and prognosis.

  20. Metal-organic gel enhanced fluorescence anisotropy for sensitive detection of prostate specific antigen

    Science.gov (United States)

    Zhao, Ting Ting; Peng, Zhe Wei; Yuan, Dan; Zhen, Shu Jun; Huang, Cheng Zhi; Li, Yuan Fang

    2018-03-01

    In this contribution, we demonstrated that Cu-based metal-organic gel (Cu-MOG) was able to serve as a novel amplification platform for fluorescence anisotropy (FA) assay for the first time, which was confirmed by the sensitive detection of a common cancer biomarker, prostate specific antigen (PSA). The dye-labeled probe aptamer (PA) product was adsorbed onto the benzimidazole derivative-containing Cu-MOG via electrostatic incorporation and strong π-π stacking interactions, which significantly increased the FA value due to the enlargement of the molecular volume of the PA/Cu-MOG complex. With the introduction of target PSA, the FA value was obviously decreased on account of the specific recognition between PSA and PA which resulted in the detachment of PA from the surface of MOG. The linear range was from 0.5-8 ng/mL, with a detection limit of 0.33 ng/mL. Our work has thus helped to demonstrate promising application of MOG material in the fields of biomolecules analysis and disease diagnosis.

  1. Detection of Avian Antigen-Specific T Cells Induced by Viral Vaccines

    DEFF Research Database (Denmark)

    Dalgaard, Tina Sørensen; Norup, Liselotte Rothmann; Juul-Madsen, Helle Risdahl

    2016-01-01

    Live attenuated viral vaccines are widely used in commercial poultry production, but the development of new effective inactivated/subunit vaccines is needed. Studies of avian antigen-specific T cells are primarily based on analyses ex vivo after activating the cells with recall antigen. There is ......Live attenuated viral vaccines are widely used in commercial poultry production, but the development of new effective inactivated/subunit vaccines is needed. Studies of avian antigen-specific T cells are primarily based on analyses ex vivo after activating the cells with recall antigen...

  2. Improving dengue viral antigens detection in dengue patient serum specimens using a low pH glycine buffer treatment.

    Science.gov (United States)

    Shen, Wen-Fan; Galula, Jedhan Ucat; Chang, Gwong-Jen J; Wu, Han-Chung; King, Chwan-Chuen; Chao, Day-Yu

    2017-04-01

    Early diagnosis of dengue virus (DENV) infection to monitor the potential progression to hemorrhagic fever can influence the timely management of dengue-associated severe illness. Nonstructural protein 1 (NS1) antigen detection in acute serum specimens has been widely accepted as an early diagnostic assay for dengue infection; however, lower sensitivity of the NS1 antigen-capture enzyme-linked immunosorbent assay (Ag-ELISA) in secondary dengue viral infection has been reported. In this study, we developed two forms of Ag-ELISA capable of detecting E-Ag containing virion and virus-like particles, and secreted NS1 (sNS1) antigens, respectively. The temporal kinetics of viral RNA, sNS1, and E-Ag were evaluated based on the in vitro infection experiment. Meanwhile, a panel of 62 DENV-2 infected patients' sera was tested. The sensitivity was 3.042 ng/mL and 3.840 ng/mL for sNS1 and E, respectively. The temporal kinetics of the appearance of viral RNA, E, NS1, and infectious virus in virus-infected tissue culture media suggested that viral RNAs and NS1 antigens could be detected earlier than E-Ag and infectious virus. Furthermore, a panel of 62 sera from patients infected by DENV Serotype 2 was tested. Treating clinical specimens with the dissociation buffer increased the detectable level of E from 13% to 92% and NS1 antigens from 40% to 85%. Inclusion of a low-pH glycine buffer treatment step in the commercially available Ag-ELISA is crucial for clinical diagnosis and E-containing viral particles could be a valuable target for acute DENV diagnosis, similar to NS1 detection. Copyright © 2015. Published by Elsevier B.V.

  3. Immunohistochemical detection of PGL-1, LAM, 30 kD and 65 kD antigens in leprosy infected paraffin preserved skin and nerve sections

    NARCIS (Netherlands)

    van den Bos, I. C.; Khanolkar-Young, S.; Das, P. K.; Lockwood, D. N.

    1999-01-01

    A panel of lipid, carbohydrate and protein antibodies were optimized for use in detecting M. leprae antigens in paraffin embedded material. Skin and nerve biopsies from 13 patients across the leprosy spectrum were studied. All antibodies detected antigen in tissues with a BI > 1. Phenolic-glycolipid

  4. Fabrication of graphene/gold-modified screen-printed electrode for detection of carcinoembryonic antigen

    Energy Technology Data Exchange (ETDEWEB)

    Chan, K.F. [Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, UPM Serdang, 43400 Selangor (Malaysia); Lim, H.N., E-mail: janetlimhn@gmail.com [Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, UPM Serdang, 43400 Selangor (Malaysia); Shams, N. [Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, UPM Serdang, 43400 Selangor (Malaysia); Jayabal, S.; Pandikumar, A.; Huang, N.M. [Low Dimensional Materials Research Centre (LDMRC), Physics Department, Faculty of Science, University of Malaya, 50603 Kuala Lumpur (Malaysia)

    2016-01-01

    Immunosensors based on gold nanoparticles and reduced graphene oxide (AuNPs/rGO)-modified screen-printed electrodes (SPEs) were successfully synthesized using an electrochemical deposition method. The modified SPEs were characterized using a field emission scanning electron microscope (FESEM) and Raman spectroscopy to analyze the morphology and composition of AuNPs and rGO. Both the FESEM and Raman spectroscopy revealed that the AuNPs were successfully anchored on the thin film of rGO deposited on the surface of the SPEs. Characterization with a ferri–ferrocyanide couple [Fe(CN){sub 6}{sup 3−/4−}] showed that the electron transfer kinetic between the analyte and electrode was enhanced after the modification with the AuNPs/rGO composite on the electrode surface, in addition to increasing the effective surface area of the electrode. The modified SPE was immobilized with a sandwich type immunosensor to mimic the ELISA (enzyme-linked immunosorbent assay) immunoassay. The modified SPE that was fortified with the sandwich type immunosensor exhibited double electrochemical responses in the detection of carcinoembryonic antigen (CEA), with linear ranges of 0.5–50 ng/mL and 250–2000 ng/mL and limits of detection of 0.28 ng/mL and 181.5 ng/mL, respectively. - Highlights: • An AuNP/rGO-modified SPE is prepared via an in-situ electrodeposition method. • It is introduced in a sandwich-type immunoassay for the detection of CEA. • The LODs for CEA are 0.28 ng/mL for 0.5–25 ng/mL, and 181.5 ng/mL for 250–2000 ng/mL.

  5. Transrectal ultrasound in detecting prostate cancer compared with serum total prostate-specific antigen levels

    International Nuclear Information System (INIS)

    Tamsel, S.; Killi, R.; Demirpolat, G.; Hekimgil, M.; Soydan, S.; Altay, B.

    2008-01-01

    We carried out a retrospective study to review the efficiency of grey-scale transrectal ultrasonography (TRUS) in detecting prostate cancer compared with the data in recent published work, including alternative imaging methods of the prostate gland. Our study group consisted of 830 patients who underwent TRUS-guided biopsy of the prostate between May 2000 and June 2004. The relation between abnormal TRUS findings and serum total prostate-specific antigen (tPSA) levels was evaluated in patients with prostate cancer who were divided into three different groups according to serum tPSA levels. Group I included patients with tPSA levels of 4-9.9 ng/mL, group II included tPSA levels of 10-19.9 ng/mL and group III included patients with tPSA levels of 20 ng/mL or more. In general, TRUS detected 185 (64%) of 291 cancers with a specificity of 89%, a PPV of 76% and an accuracy of 80%. TRUS findings enabled the correct identification of 22 (56%) of the 39 cancers in group I, 28 (30%) of the 93 cancers in group II and 135 (85%) of the 159 cancers in group III. In conclusion, TRUS alone has a limited potential to identify prostate cancer, especially in patients with tPSA levels lower than 20 ng/mL. Therefore, increased numbers of systematically placed biopsy cores must be taken or alternative imaging methods are required to direct TRUS-guided biopsy for improving prostate cancer detection.

  6. Detection of intracellular canine distemper virus antigen in mink inoculated with an attenuated or a virulent strain of canine distemper virus.

    Science.gov (United States)

    Blixenkrone-Møller, M

    1989-09-01

    Using an indirect immunofluorescence technique, the distribution of viral antigen in various tissues and blood mononuclear leukocytes was studied in wild mink, either vaccinated with an attenuated vaccine strain of canine distemper virus (CDV) or experimentally inoculated with the virulent Snyder-Hill strain of CDV. Viral antigen was detected in cells of the lymphoid system 6 to 12 days after vaccination. From 2 to 3 days after inoculation with the virulent strain, CDV antigen was demonstrated in cells of the lymphoid system and, during the incubation period, the antigen had spread to the epithelia and brain at days 6 and 12, respectively. In clinical cases of acute fatal canine distemper, the viral antigen was detected in a wide variety of tissues, including the cells of the lymphoid system, epithelial cells of skin, mucous membranes, lung, kidney, and cells of the CNS. The diagnostic importance of CDV antigen detection is discussed on the basis of these findings.

  7. Quantitative detection of the tumor-associated antigen large external antigen in colorectal cancer tissues and cells using quantum dot probe

    Directory of Open Access Journals (Sweden)

    Wang S

    2016-01-01

    Full Text Available Shuo Wang, Wanming Li, Dezheng Yuan, Jindan Song, Jin Fang Department of Cell Biology, Key Laboratory of Cell Biology, Ministry of Public Health, and Key Laboratory of Medical Cell Biology, Ministry of Education, China Medical University, Shenyang, People’s Republic of China Abstract: The large external antigen (LEA is a cell surface glycoprotein that has been proven to be highly expressed in colorectal cancer (CRC as a tumor-associated antigen. To evaluate and validate the relationship between LEA expression and clinical characteristics of CRC with high efficiency, LEA expression levels were detected in 85 tissue blocks from CRC patients by quantum dot-based immunohistochemistry (QD-IHC combined with imaging quantitative analysis using quantum dots with a 605 nm emission wavelength (QD605 conjugated to an ND-1 monoclonal antibody against LEA as a probe. Conventional IHC was performed in parallel for comparison. Both QD-IHC and conventional IHC showed that LEA was specifically expressed in CRC, but not in non-CRC tissues, and high LEA expression was significantly associated with a more advanced T-stage (P<0.05, indicating that LEA is likely to serve as a CRC prognostic marker. Compared with conventional IHC, receiver operating characteristic analysis revealed that QD-IHC possessed higher sensitivity, resulting in an increased positive detection rate of CRC, from 70.1% to 89.6%. In addition, a simpler operation, objective analysis of results, and excellent repeatability make QD-IHC an attractive alternative to conventional IHC in clinical practice. Furthermore, to explore whether the QD probes can be utilized to quantitatively detect living cells or single cells, quantum dot-based immunocytochemistry (QD-ICC combined with imaging quantitative analysis was developed to evaluate LEA expression in several CRC cell lines. It was demonstrated that QD-ICC could also predict the correlation between LEA expression and the T-stage characteristics of

  8. Inclusion bodies of recombinant Epstein-Barr virus capsid antigen p18 as potential immobilized antigens in enzyme immunoassays for detection of nasopharyngeal carcinoma.

    Science.gov (United States)

    Lim, Chun Shen; Goh, Siang Ling; Kariapper, Leena; Krishnan, Gopala; Lim, Yat-Yuen; Ng, Ching Ching

    2015-08-25

    Development of indirect enzyme-linked immunosorbent assays (ELISAs) often utilizes synthetic peptides or recombinant proteins from Escherichia coli as immobilized antigens. Because inclusion bodies (IBs) formed during recombinant protein expression in E. coli are commonly thought as misfolded aggregates, only refolded proteins from IBs are used to develop new or in-house diagnostic assays. However, the promising utilities of IBs as nanomaterials and immobilized enzymes as shown in recent studies have led us to explore the potential use of IBs of recombinant Epstein-Barr virus viral capsid antigen p18 (VCA p18) as immobilized antigens in ELISAs for serologic detection of nasopharyngeal carcinoma (NPC). Thioredoxin fusion VCA p18 (VCA-Trx) and IBs of VCA p18 without fusion tags (VCA-IBs) were purified from E. coli. The diagnostic performances of IgG/VCA-IBs, IgG/VCA-Denat-IBs (using VCA-IBs coated in 8mol/l urea), IgG/VCA-Trx, and IgG/VCA-Peptide assays were compared by screening 100 NPC case-control pairs. The IgG/VCA-Denat-IBs assay showed the best area under the receiver operating characteristic curve (AUC: 0.802; p<0.05), while the AUCs for the IgG/VCA-IBs, IgG/VCA-Trx, and IgG/VCA-Peptide assays were comparable (AUC: 0.740, 0.727, and 0.741, respectively). We improved the diagnostic performance of the ELISA significantly using IBs of recombinant VCA p18. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Anti-Taenia solium monoclonal antibodies for the detection of parasite antigens in body fluids from patients with neurocysticercosis.

    Science.gov (United States)

    Paredes, Adriana; Sáenz, Patricia; Marzal, Miguel W; Orrego, Miguel A; Castillo, Yesenia; Rivera, Andrea; Mahanty, Siddhartha; Guerra-Giraldez, Cristina; García, Hector H; Nash, Theodore E

    2016-07-01

    Neurocysticercosis (NCC), an infection of the brain by Taenia solium (Ts) cysts, is the most common cause of adult-onset epilepsy in developing countries. Serological testing consists primarily of varying methods to detect antibodies in body fluids and more recently antigen (Ag) detection assays to identify individuals or animals with viable parasites. Antigen assays currently in use employ monoclonal antibodies (mAbs) raised against T. saginata, which have known cross reactivity to animal cestodes but are highly specific in human samples. We produced, characterized and tested 21 mAbs raised against T. solium whole cyst antigens, vesicular fluid or excretory secretory products. Reactivity of the TsmAbs against specific cyst structures was determined using immunofluorescence and immunohistochemistry on histological sections of Ts muscle cysts. Four TsmAbs reacted to vesicular space alone, 9 to the neck and cyst wall, one to the neck and vesicular space and 7 to the neck, cyst wall and vesicular space. An in-house ELISA assay to detect circulating Ts antigen, using the TsmAbs as capture antibodies and a rabbit polyclonal anti-Ts whole cyst antibody as a detector antibody demonstrated that eight of the 21 TsmAbs detected antigens in known NCC-positive human sera and three of these also in urine samples. Reactivity was expressed as normalized ratios of optical densities (OD positive control/OD negative control). Three TsmAbs had ratios >10 and five between 2 and 10. The TsmAbs have potential utility for the diagnosis and post-treatment monitoring of patients with viable NCC infections. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. Next-generation detection of antigen-responsive T cells using DNA barcode-labeled peptidemajor histocompatibility complex I multimers

    DEFF Research Database (Denmark)

    Bentzen, Amalie Kai; Marquard, Andrea Marion; Lyngaa, Rikke Birgitte

    2016-01-01

    diversity of T cell recognition in humans. Consequently it has been impossible to comprehensively analyze T cell responsiveness in cancer, infectious and autoimmune diseases. We present and validate a novel technology that enables parallel detection of numerous different peptide-MHC responsive T cells...... with combinatorial encoding of fluorescent-labeled MHC multimers. Finally, we have demonstrated that this technology can be applied for multiplex T cell detection both in limited biological samples, such as uncultured tumor material, and for simultaneous assessment of target recognition and functional capability...... of T cells. This technology enables true high-throughput detection of antigen-responsive T cells and will advance our understanding of immune recognition from model antigens to genomewide immune assessments on a personalized basis....

  11. Detection of Giardia duodenalis antigen in human fecal eluates by enzyme-linked immunosorbent assay using polyclonal antibodies

    Directory of Open Access Journals (Sweden)

    Sofía Duque-Beltrán

    2002-12-01

    Full Text Available The present study developed and standardized an enzime-linked immunosorbent assay (ELISA to detect Giardia antigen in feces using rabbit polyclonal antibodies. Giardia cysts were purified from human fecal samples by sucrose and percoll gradients. Gerbils (Meriones unguiculatus were infected to obtain trophozoites. Rabbits were inoculated with either cyst or trophozoite antigens of 14 Colombian Giardia isolates to develop antibodies against the respective stages. The IgG anti-Giardia were purified by sequential caprylic acid and ammonium sulfate precipitation. A portion of these polyclonal antibodies was linked to alkaline phosphatase (conjugate. One hundred and ninety six samples of human feces, from different patients, were tested by parasitologic diagnosis: 69 were positive for Giardia cysts, 56 had no Giardia parasites, and 71 revealed parasites other than Giardia. The optimal concentration of polyclonal antibodies for antigen capture was 40 µg/ml and the optimal conjugate dilution was 1:100. The absorbance cut-off value was 0.24. The parameters of the ELISA test for Giardia antigen detection were: sensitivity, 100% (95% CI: 93.4-100%; specificity, 95% (95% CI: 88.6-97.6%; positive predictive value, 91% (95% CI: 81.4-95.9%; and negative predictive value, 100% (95% CI: 96.1-100%. This ELISA will improve the diagnosis of Giardia infections in Colombia and will be useful in following patients after treatment.

  12. Two types of nanoparticle-based bio-barcode amplification assays to detect HIV-1 p24 antigen

    Directory of Open Access Journals (Sweden)

    Dong Huahuang

    2012-08-01

    Full Text Available Abstract Background HIV-1 p24 antigen is a major viral component of human immunodeficiency virus type 1 (HIV-1 which can be used to identify persons in the early stage of infection and transmission of HIV-1 from infected mothers to infants. The detection of p24 is usually accomplished by using an enzyme-linked immunosorbent assay (ELISA with low detection sensitivity. Here we report the use of two bio-barcode amplification (BCA assays combined with polymerase chain reaction (PCR and gel electrophoresis to quantify HIV-1 p24 antigen. Method A pair of anti-p24 monoclonal antibodies (mAbs were used in BCA assays to capture HIV-1 p24 antigen in a sandwich format and allowed for the quantitative measurement of captured p24 using PCR and gel electrophoresis. The first 1 G12 mAb was coated on microplate wells or magnetic microparticles (MMPs to capture free p24 antigens. Captured p24 in turn captured 1D4 mAb coated gold nanoparticle probes (GNPs containing double-stranded DNA oligonucleotides. One strand of the oligonucleotides was covalently immobilized whereas the unbound complimentary bio-barcode DNA strand could be released upon heating. The released bio-barcode DNA was amplified by PCR, electrophoresed in agarose gel and quantified. Results The in-house ELISA assay was found to quantify p24 antigen with a limit of detection (LOD of 1,000 pg/ml and a linear range between 3,000 and 100,000 pg/ml. In contrast, the BCA-based microplate method yielded an LOD of 1 pg/ml and a linear detection range from 1 to 10,000 pg/ml. The BCA-based MMP method yielded an LOD of 0.1 pg/ml and a linear detection range from 0.1 to 1,000 pg/ml. Conclusions When combined with PCR and simple gel electrophoresis, BCA-based microplate and MMPs assays can be used to quantify HIV-1 p24 antigen. These methods are 3–4 orders of magnitude more sensitive than our in-house ELISA-based assay and may provide a useful approach to detect p24 in patients newly infected

  13. [Detection of fps tumor antigen with mono-specific anti-fps serum in tumors induced by acute transforming ALV].

    Science.gov (United States)

    Wang, Yixin; Chen, Hao; Zhao, Peng; Li, Jianliang; Cui, Zhizhong

    2013-03-04

    To prepare anti-fps mono-specific serum, and detect the fps antigen in tumors induced by acute transforming avian leukosis/sarcoma virus containing v-fps oncogene. Two part of v-fps gene was amplified by RT-PCR using the Fu-J viral RNA as the template. Mono-specific serum was prepared by immuning Kunming white mouse with both two recombinant infusion proteins expressed by the prokaryotic expression system. Indirect immunofluorescent assay was used to detect fps antigen in tumor tissue suspension cells and CEF infected by sarcoma supernatant. Immunohistochemical method was used to detect fps antigen in tumor tissue. The mouse mono-specific serum was specific as it had no cross reaction with classical ALV-J strains. The result reveals that the tumor tissue suspension cells, the CEF infected by sarcoma supernatant, and the slice immunohistochemistry of the sarcoma showed positive results. The anti-fps mono-specific serum was prepared, and the detection method was established, which laid the foundation for the study of viral biological characteristics and mechanism of tumourgenesis of acute transforming avian leukosis/sarcoma virus containing v-fps oncogene.

  14. Hyperplasia of elastic tissue in hepatic schistosomal fibrosis

    Directory of Open Access Journals (Sweden)

    Zilton A. Andrade

    1991-12-01

    Full Text Available Elastic tissue hyperplasia, revealed by means of histological, immunocytochemical and ultrastructural methods, appeared as a prominent change in surgical liver biopsies taken from 61 patients with schistosomal periportal and septal fibrosis. Such hyperplasia was absent in ecperimental murine schistosomiasis, including mice with "pipe-stem" fibrosis. Displaced connective tissue cells in periportal areas, such as smooth muscle cells, more frequently observed in human material, could be the site of excessive elastin synthesis, and could explain the differences observed in human and experimental materials. Elastic tissue, sometimes represented by its microfibrillar components, also appeared to be more condensed in areas of matrix (collagen degradation, suggesting a participation of this tissue in the remodelling of the extracellular matrix. By its rectratile properties elastic tissue hyperplasia in hepatic schistosomiasis can cause vascular narrowing and thus play a role in the pathogenesis of portal hypeertension.

  15. Antigen detection of rabies virus in brain smear using direct Rapid Immunohistochemistry Test

    Directory of Open Access Journals (Sweden)

    Damayanti R

    2014-03-01

    Full Text Available Rabies is zoonotic disease caused by a fatal, neurotropic virus. Rabies virus is classified into the Genus of Lyssavirus under the yang family of Rhabdoviridae. Rabies affecting hot- blooded animals, as well as human. Dogs, cats, monkeys are the vectors or reservoirs for rabies and the virus was transmitted through the saliva after infected animal’s bites. The aim of this study was to conduct rapid diagnosis to detect rabies viral antigen in brain smear using immunohistochemical (IHC method namely direct Rapid Immunohistochemical Test (dRIT. A total number of 119 brain samples were achieved from Bukittinggi Veterinary Laboratory, West Sumatra. Standardisation and validation of the method were compared to Fluorescent Antibody Test (FAT as a golden standard for rabies diagnosis. Results show that dRIT was a very good method, it can be performed within two hours without the need of fluorescent microscope. The samples were tested using FAT and from 119 samples tested, 80 (67.23% samples were positive for rabies and 39 (32.77% samples were negative for rabies whereas using dRIT showed that 78 (65.54% samples were positive for rabies and 41 (34.45% samples were negative for rabies. The dRIT results were validated by comparing them with FAT results as a golden standard for rabies. The relative sensitivity of dRIT to FAT was 97.5% and the relative specificity to FAT was 100% (with Kappa value of 0.976, stated as excellent. The achievement showed that dRIT is very potential diagnostic tool and is highly recommended to be used widely as a rapid diagnosis tool for rabies.

  16. Comparison of nine antigen detection kits for diagnosis of urogenital infections due to Chlamydia psittaci in koalas.

    OpenAIRE

    Wood, M M; Timms, P

    1992-01-01

    Chlamydia psittaci is the major cause of infectious disease in the koala (Phascolarctos cinereus). It causes four disease syndromes in the koala, namely, conjunctivitis, rhinitis, cystitis, and infertility (females only). Diagnosis of chlamydial infections in koalas relies primarily on isolation of the organism in cell culture. Serology has generally not been useful, and little use has previously been made of the commercially available antigen detection kits. We examined the sensitivity, spec...

  17. Detection of soluble antigens of Toxoplasma gondii by a four-layer modification of an enzyme immunoassay.

    OpenAIRE

    Turunen, H J

    1983-01-01

    A sensitive four-layer modification of an enzyme immunoassay for the detection of soluble antigens of Toxoplasma gondii is described. Microtiter plates were sensitized with rabbit anti-toxoplasma immunoglobulins (6 micrograms/ml) used as the primary antibodies; guinea pig anti-toxoplasma immunoglobulins (6 micrograms/ml) were used as the secondary trapping antibodies. Horseradish peroxidase-conjugated anti-guinea pig immunoglobulins were used as the indicator antibodies. The specificity of th...

  18. Use of Digital Rectal Examination as an Adjunct to Prostate Specific Antigen in the Detection of Clinically Significant Prostate Cancer.

    Science.gov (United States)

    Halpern, Joshua A; Oromendia, Clara; Shoag, Jonathan E; Mittal, Sameer; Cosiano, Michael F; Ballman, Karla V; Vickers, Andrew J; Hu, Jim C

    2018-04-01

    Guidelines from the NCCN ® (National Comprehensive Cancer Network®) advocate digital rectal examination screening only in men with elevated prostate specific antigen. We investigated the effect of prostate specific antigen on the association of digital rectal examination and clinically significant prostate cancer in a large American cohort. We evaluated the records of the 35,350 men who underwent digital rectal examination in the screening arm of the Prostate, Lung, Colorectal and Ovarian Cancer Screening trial for the development of clinically significant prostate cancer (Gleason 7 or greater). Followup was 343,273 person-years. The primary outcome was the rate of clinically significant prostate cancer among men with vs without suspicious digital rectal examination. We performed competing risks regression to evaluate the interaction between time varying suspicious digital rectal examination and prostate specific antigen. A total of 1,713 clinically significant prostate cancers were detected with a 10-year cumulative incidence of 5.9% (95% CI 5.6-6.2). Higher risk was seen for suspicious vs nonsuspicious digital rectal examination. Increases in absolute risk were small and clinically irrelevant for normal (less than 2 ng/ml) prostate specific antigen (1.5% vs 0.7% risk of clinically significant prostate cancer at 10 years), clinically relevant for elevated (3 ng/ml or greater) prostate specific antigen (23.0% vs 13.7%) and modestly clinically relevant for equivocal (2 to 3 ng/ml) prostate specific antigen (6.5% vs 3.5%). Digital rectal examination demonstrated prognostic usefulness when prostate specific antigen was greater than 3 ng/ml, limited usefulness for less than 2 ng/ml and marginal usefulness for 2 to 3 ng/ml. These findings support the restriction of digital rectal examination to men with higher prostate specific antigen as a reflex test to improve specificity. It should not be used as a primary screening modality to improve sensitivity. Copyright

  19. Optimization of Diagnostic Elisa - Based Tests for the Detection of Auto-Antibodies Against Tumor Antigens in Human Serum

    Directory of Open Access Journals (Sweden)

    Daria Štefatić

    2008-08-01

    Full Text Available Colorectal cancer is one of the most common cancer types worldwide and it continues to be a serious public health problem. Early detection and diagnosis are of great importance in cancer management. At present, diagnostic blood tests are based on the detection of tumor-associated markers such as carcinoembryonic antigen (CEA, the cancer antigen CA19-9 for gastrointestinal cancer, CA15-3 for breast cancer or CA125 for ovarian cancer. The lack of sensitivity and specificity of these markers prevents their general use in cancer screening of an average risk population. Therefore, new cancer biomarkers or better screening methods are necessary to improve the diagnostics of the disease. This study was directed to the optimization of a diagnostic, enzyme linked immunosorbent assay (ELISA based test to identify and validate new serum markers, such as extracellular Protein Kinase A (ecPKA and Nicotinamide A-Meth- yltransferase (NNMT. In this type of assay, the cancer antigens are quantified indirectly - by detecting the presence of auto-antibodies against tumor proteins in human serum. The result of the optimization and validation process was in the case of ecPKA a reproducible and stable assay. In case of NNMT the assay was probably not sensitive enough.

  20. Development of a Novel, Ultra-rapid Biosensor for the Qualitative Detection of Hepatitis B Virus-associated Antigens and Anti-HBV, Based on “Membrane-engineered” Fibroblast Cells with Virus-Specific Antibodies and Antigens

    Directory of Open Access Journals (Sweden)

    Antonios Perdikaris

    2009-03-01

    Full Text Available A novel miniature cell biosensor detection system for the detection of Hepatis B virus (HBV-associated antigens and anti-HBV is described. The biosensor is based on “membrane-engineered” Vero fibroblast cells immobilized in an alginate matrix. The membrane-engineering process involved the electroinsertion of anti-HBV specific antibodies (anti-HBs, anti-HBe or antigens (HBsAg in the membranes of the Vero cells. The attachment of a homologous antigen to the electroinserted antibody (or, respectively, of the antibody to the electroinserted antigen triggered specific changes to the cell membrane potential that were measured by appropriate microelectrodes, according to the principle of the Bioelectric Recognition Assay (BERA. The sensor was used for screening 133 clinical blood serum samples according to a double-blind protocol. Considerably higher sensor responses were observed against HBV-positive samples, compared with responses against negative samples or samples positive for heterologous hepatitis viruses such as Hepatitis C (HCV virus. Detection of anti-HBs antibodies was made possible by using a biosensor based on immobilized Vero cells bearing the respective antigen (HBsAg. The observed response was rapid (45 sec and quite reproducible. Fluorescence microscopy observations showed that attachment of HBV particles to cells membrane-engineered with anti-HBs was associated with a decrease of [Ca2+]cyt. The perspectives for using the novel biosensor as a qualitative, rapid screening, high throughput assay for HBV antigens and anti-HBs in clinical samples is discussed.

  1. Studies on Antigenic Communities between the Yamanashi and Chinese Strains of Schistosoma japonicum Eggs and Oncomelania Snails by Immunoelectrophoresis

    OpenAIRE

    Iwanaga, Yuzuru; Tsuji, Moriyasu; Tanaka, Noriyasu

    1988-01-01

    Antigenic communities were studied with sera from rabbits immunized with the Yamanashi and Chinese strains of Schistosoma japonicum eggs, and the antigens of five subspecies of Oncomelania snails, by immunoelectrophoresis. With regard to antigenic communities defined by the Yamanashi strain of S. japonicum eggs and Oncomelania snails, the schistosome egg produced 5 to 6 bands with Oncomelania hupensis nosophora, 3 to 4 bands with O.h.hupensis, 3 bands with O.h.chiui, 2 bands with O.h.quad...

  2. Use of a solid-phase radioimmunoassay and formalin-fixed whole bacterial antigen in the detection of antigen-specific immunoglobulin in prostatic fluid.

    OpenAIRE

    Shortliffe, L M; Wehner, N; Stamey, T A

    1981-01-01

    The prostatic fluid of two patients with Escherichia coli bacterial prostatitis was analyzed for evidence of a local immune response to bacterial infection. A solid-phase radioimmunoassay was modified to measure the immunoglobulin (Ig)A and IgG antigen-specific antibody responses to infecting bacteria in serum and prostatic fluid from patient. Formalin-fixed whole E. coli were used as antigen. In one patient with acute E. coli prostatic infection, measurements of antigen-specific antibody con...

  3. Detection and Antigenic Profiling of Undeclared Peanut in Imported Garlic Using an xMAP Multiplex Immunoassay for Food Allergens.

    Science.gov (United States)

    Pedersen, Ronnie O; Peters, Tim; Panda, Rakhi; Wehling, Paul; Garber, Eric A E

    2017-07-01

    A shipment of imported garlic powder was suspected of containing peanut. Samples (subs) collected from the shipment displayed considerable variability in peanut antigenicity when analyzed by enzyme-linked immunosorbent assay (ELISA). This raised questions regarding whether peanut was actually present, the amount present, and the basis for the variability in antigenic content. Analyses that used an xMAP multiplex assay for the detection of peanut and additional food allergens generated responses that were characteristic of peanut. Specifically, the relative intensities of two different peanut-specific antibodies coupled to beads (peanut-37 and -38) and the antigen profiles were identical to garlic controls spiked with peanut. In addition, the xMAP data did not indicate the presence of other allergens. Quantitative analyses indicated an approximately fivefold variation in peanut concentration among different subs. In contrast, within a sub, the apparent peanut concentration appeared constant. Particle size analyses of the garlic powder subs indicated a single distribution profile, with a peak at 380 μm. ELISA analysis of sieve-fractionated garlic powder from one of the subs indicated that slightly less than half of the detectable peanut was smaller than 212 μm, with the remainder almost evenly split between 212 and 300 μm and >300 μm. Modeling to predict possible oral exposure levels of peanut other than those directly measured requires additional research on the physicochemical properties of peanut and garlic, along with information on the production of the garlic powder.

  4. The use of antigen-detection ELISA for the diagnosis of bovine trypanosomosis in Cote d'Ivoire

    International Nuclear Information System (INIS)

    Kone, P.; Komoin-Oka, C.; N'Depo, A.

    1997-01-01

    An Antigen ELISA (Ag-ELISA) detecting circulating antigens of trypanosomes was evaluated in the central region of Cote d'Ivoire for the serodiagnosis of cattle trypanosomosis. Of 1423 sera examined, only 43 were positive in the MHCT/BCT, 105 (7%) were detected using stained blood smears, and 74 (5%) were found positive using the Ag-ELISA. The predominant trypanosome species was T. brucei, being present in 84% of the positive samples as detected by the BCT, in 96% using stained bloodsmears, and in 72% by Ag-ELISA. T.vivax was detected less frequently. The serological (ELISA) test did not detect all positive animals as found by the haematological techniques. However, the two techniques should be used in a complementary way to improve the diagnosis of the disease. The results confirm that the prevalence of trypanosomes in cattle is low in the study area. The low prevalence can be due to prophylaxis and therapy of livestock in combination with successful tsetse trapping. (author). 4 refs, 2 figs, 4 tabs

  5. The use of antigen-detection ELISA for the diagnosis of bovine trypanosomosis in Cote d`Ivoire

    Energy Technology Data Exchange (ETDEWEB)

    Kone, P [Laboratoire Regional de Pathologie Animale de Bouake (LANADA), Bouake (Cote d` Ivoire); Komoin-Oka, C; N` Depo, A [Laboratoire Central de Pathologie Animale de Bingerville (LANADA), Bingerville (Cote d` Ivoire)

    1997-02-01

    An Antigen ELISA (Ag-ELISA) detecting circulating antigens of trypanosomes was evaluated in the central region of Cote d`Ivoire for the serodiagnosis of cattle trypanosomosis. Of 1423 sera examined, only 43 were positive in the MHCT/BCT, 105 (7%) were detected using stained blood smears, and 74 (5%) were found positive using the Ag-ELISA. The predominant trypanosome species was T. brucei, being present in 84% of the positive samples as detected by the BCT, in 96% using stained bloodsmears, and in 72% by Ag-ELISA. T.vivax was detected less frequently. The serological (ELISA) test did not detect all positive animals as found by the haematological techniques. However, the two techniques should be used in a complementary way to improve the diagnosis of the disease. The results confirm that the prevalence of trypanosomes in cattle is low in the study area. The low prevalence can be due to prophylaxis and therapy of livestock in combination with successful tsetse trapping. (author). 4 refs, 2 figs, 4 tabs.

  6. Development and validation of an immunoperoxidase antigen detection test for improved diagnosis of rabies in Indonesia.

    Science.gov (United States)

    Rahmadane, Ibnu; Certoma, Andrea F; Peck, Grantley R; Fitria, Yul; Payne, Jean; Colling, Axel; Shiell, Brian J; Beddome, Gary; Wilson, Susanne; Yu, Meng; Morrissy, Chris; Michalski, Wojtek P; Bingham, John; Gardner, Ian A; Allen, John D

    2017-11-01

    Rabies continues to pose a significant threat to human and animal health in regions of Indonesia. Indonesia has an extensive network of veterinary diagnostic laboratories and the 8 National laboratories are equipped to undertake diagnostic testing for rabies using the commercially-procured direct fluorescent antibody test (FAT), which is considered the reference (gold standard) test. However, many of the Indonesian Provincial diagnostic laboratories do not have a fluorescence microscope required to undertake the FAT. Instead, certain Provincial laboratories continue to screen samples using a chemical stain-based test (Seller's stain test, SST). This test has low diagnostic sensitivity, with negative SST-tested samples being forwarded to the nearest National laboratory resulting in significant delays for completion of testing and considerable additional costs. This study sought to develop a cost-effective and diagnostically-accurate immunoperoxidase antigen detection (RIAD) test for rabies that can be readily and quickly performed by the resource-constrained Provincial laboratories. This would reduce the burden on the National laboratories and allow more rapid diagnoses and implementation of post-exposure prophylaxis. The RIAD test was evaluated using brain smears fixed with acetone or formalin and its performance was validated by comparison with established rabies diagnostic tests used in Indonesia, including the SST and FAT. A proficiency testing panel was distributed between Provincial laboratories to assess the reproducibility of the test. The performance of the RIAD test was improved by using acetone fixation of brain smears rather than formalin fixation such that it was of equivalent accuracy to that of the World Organisation for Animal Health (OIE)-recommended FAT, with both tests returning median diagnostic sensitivity and specificity values of 0.989 and 0.993, respectively. The RIAD test and FAT had higher diagnostic sensitivity than the SST (median = 0

  7. Development and validation of an immunoperoxidase antigen detection test for improved diagnosis of rabies in Indonesia.

    Directory of Open Access Journals (Sweden)

    Ibnu Rahmadane

    2017-11-01

    Full Text Available Rabies continues to pose a significant threat to human and animal health in regions of Indonesia. Indonesia has an extensive network of veterinary diagnostic laboratories and the 8 National laboratories are equipped to undertake diagnostic testing for rabies using the commercially-procured direct fluorescent antibody test (FAT, which is considered the reference (gold standard test. However, many of the Indonesian Provincial diagnostic laboratories do not have a fluorescence microscope required to undertake the FAT. Instead, certain Provincial laboratories continue to screen samples using a chemical stain-based test (Seller's stain test, SST. This test has low diagnostic sensitivity, with negative SST-tested samples being forwarded to the nearest National laboratory resulting in significant delays for completion of testing and considerable additional costs. This study sought to develop a cost-effective and diagnostically-accurate immunoperoxidase antigen detection (RIAD test for rabies that can be readily and quickly performed by the resource-constrained Provincial laboratories. This would reduce the burden on the National laboratories and allow more rapid diagnoses and implementation of post-exposure prophylaxis. The RIAD test was evaluated using brain smears fixed with acetone or formalin and its performance was validated by comparison with established rabies diagnostic tests used in Indonesia, including the SST and FAT. A proficiency testing panel was distributed between Provincial laboratories to assess the reproducibility of the test. The performance of the RIAD test was improved by using acetone fixation of brain smears rather than formalin fixation such that it was of equivalent accuracy to that of the World Organisation for Animal Health (OIE-recommended FAT, with both tests returning median diagnostic sensitivity and specificity values of 0.989 and 0.993, respectively. The RIAD test and FAT had higher diagnostic sensitivity than the SST

  8. Detection and partial characterization of a midlamina lucida-hemidesmosome-associated antigen (19-DEJ-1) present within human skin

    DEFF Research Database (Denmark)

    Fine, J D; Horiguchi, Y; Jester, J

    1989-01-01

    , esophagus, cervix, and cornea, and BMs surrounding smooth muscle in medium-sized vessels, placenta, uterus, and esophagus. When 16 human fetal skins (aged 54-142 gestational days) were examined, the antigen was first detected at 81 days. Using immunoperoxidase and immunogold staining techniques, indirect......A murine anti-human monoclonal antibody (19-DEJ-1) has been produced that binds to basement membranes (BMs) of the dermoepidermal junction and arrector pili muscles but not to either dermal glandular or vascular BMs. 19-DEJ-1 also recognizes BMs underneath epithelia of buccal mucosa, tongue......-specific proteoglycan that is present within BMs along the epithelial-connective tissue interface and around smooth muscle in skin and other selected organs. Its unique ultrastructural localization suggests the possibility that 19-DEJ-1 may recognize an antigenic epitope of either anchoring filaments or alternatively...

  9. Evaluation of two reverse passive haemagglutination techniques and a solid-phase radioimmunoassay for detection of hepatitis B surface antigen

    Energy Technology Data Exchange (ETDEWEB)

    Zhuang, H [Beijing Medical College (China); Coulepis, A G; Gust, I D [Fairfield Hospital for Communicable Diseases, Melbourne (Australia)

    1972-08-01

    The sensitivity and specificity of two commercially available reverse passive haemagglutination tests (Hepatest and Raphadex B) for the detection of hepatitis B surface antigen, were compared with the most widely used radioimmunoassay (Ausria II-125). A selected group of 282 sera were tested: these included the Australian hepatitis B reference panel, and a batch of 257 sera collected from patients with acute hepatitis B, chronic carriers of hepatitis B surface antigen and two populations in which hepatitis B virus infection is known to be endemic. The two reverse passive haemagglutination techniques were of comparable sensitivity but slightly less sensitive than radioimmunoassay. While radioimmunoassay still remains the test of choice for blood transfusion services, the reverse passive haemagglutination techniques are of great value for smaller laboratories and for field studies because of their longer shelf life, the absence of radioactive reagents and the lack of need to acquire a gammacounter.

  10. Detection and localization of rabbit hepatitis e virus and antigen in systemic tissues from experimentally intraperitoneally infected rabbits.

    Directory of Open Access Journals (Sweden)

    Jingjing Mao

    Full Text Available Rabbit hepatitis E virus (HEV is a novel genotype of HEV, and is considered to pose a risk of zoonotic transmission. Research into the systemic distribution of rabbit HEV in rabbits during different periods of infection has rarely been reported. To better understand this virus, we infected rabbits with second-passage rabbit HEV via an intraperitoneal route. After inoculation, the infection showed two types, temporary and constant infection. The detection of HEV RNA in the feces varied with time, and serum antigen correlated with fecal HEV RNA. Viremia only appeared 72 days after inoculation. The rabbits remained antibody negative throughout the experimental period. When HEV was localized, several organs besides the liver were HEV RNA positive. Tissue antigen was observed immunohistochemically in the different cells of various organs, especially in parts of the small intestine and the characteristic rabbit gut-associated lymphoid tissue. These data provide valuable information for future research into the pathogenesis of HEV.

  11. Oriented Immobilization of Fab Fragments by Site-Specific Biotinylation at the Conserved Nucleotide Binding Site for Enhanced Antigen Detection.

    Science.gov (United States)

    Mustafaoglu, Nur; Alves, Nathan J; Bilgicer, Basar

    2015-09-08

    Oriented immobilization of antibodies and antibody fragments has become increasingly important as a result of the efforts to reduce the size of diagnostic and sensor devices to miniaturized dimensions for improved accessibility to the end-user. Reduced dimensions of sensor devices necessitate the immobilized antibodies to conserve their antigen binding activity for proper operation. Fab fragments are becoming more commonly used in small-scaled diagnostic devices due to their small size and ease of manufacture. In this study, we used the previously described UV-NBS(Biotin) method to functionalize Fab fragments with IBA-EG11-Biotin linker utilizing UV energy to initiate a photo-cross-linking reaction between the nucleotide binding site (NBS) on the Fab fragment and IBA-Biotin molecule. Our results demonstrate that immobilization of biotinylated Fab fragments via UV-NBS(Biotin) method generated the highest level of immobilized Fab on surfaces when compared to other typical immobilization methods while preserving antigen binding activity. UV-NBS(Biotin) method provided 432-fold, 114-fold, and 29-fold improved antigen detection sensitivity than physical adsorption, NHS-Biotin, and ε-NH3(+), methods, respectively. Additionally, the limit of detection (LOD) for PSA utilizing Fab fragments immobilized via UV-NBS(Biotin) method was significantly lower than that of the other immobilization methods, with an LOD of 0.4 pM PSA. In summary, site-specific biotinylation of Fab fragments without structural damage or loss in antigen binding activity provides a wide range of application potential for UV-NBS immobilization technique across numerous diagnostic devices and nanotechnologies.

  12. A sensitive immunoradiometric assay for the detection of hepatitis B surface antigen

    International Nuclear Information System (INIS)

    Cameron, C.H.; Combridge, B.S.; Howell, D.R.; Barbara, J.A.J.

    1980-01-01

    A solid-phase immunoradiometric assay for hepatitis B surface antigen is described which has been in use since 1972. Initially it was used for reference laboratory work, but from 1974 it has also been used for screening blood and blood products. Methods for the production of reagents and their use in blood transfusion and reference work, are outlined. (Auth.)

  13. Method to conjugate polysaccharide antigens to surfaces for the detection of antibodies

    DEFF Research Database (Denmark)

    Boas, Ulrik; Lind, Peter; Riber, Ulla

    2014-01-01

    microbeads modified with N-alkyl hydroxylamine and N-alkyl-O-methyl hydroxylamine surface groups by incubation of antigen and beads for 16 h at 40 oC without the need for coupling agents. The efficiency of the new method was evaluated by flow cytometry in model samples and serum samples containing antibodies...

  14. Detection of immune-complex-dissociated nonstructural-1 antigen in patients with acute dengue virus infections

    NARCIS (Netherlands)

    P. Koraka (Penelope); C.P. Burghoorn-Maas; A. Falconar; T.E. Setiati (Tatty); K. Djamiatun; J. Groen (Jan); A.D.M.E. Osterhaus (Albert)

    2003-01-01

    textabstractAccurate and timely diagnosis of dengue virus (DEN) infections is essential for the differential diagnosis of patients with febrile illness and hemorrhagic fever. In the present study, the diagnostic value of a newly developed immune-complex dissociated nonstructural-1 (NS-1) antigen dot

  15. Detection of immune-complex-dissociated nonstructural-1 antigen in patients with acute dengue virus infections.

    NARCIS (Netherlands)

    Koraka, P.; Burghoorn-Maas, C.P.; Falconar, A.; Setiati, T.E.; Djamiatun, K.; Groen, J.; Osterhaus, A.D.

    2003-01-01

    Accurate and timely diagnosis of dengue virus (DEN) infections is essential for the differential diagnosis of patients with febrile illness and hemorrhagic fever. In the present study, the diagnostic value of a newly developed immune-complex dissociated nonstructural-1 (NS-1) antigen dot blot

  16. Enzyme-linked immunosorbent assays for detection of equine antibodies specific to Sarcocystis neurona surface antigens.

    Science.gov (United States)

    Hoane, Jessica S; Morrow, Jennifer K; Saville, William J; Dubey, J P; Granstrom, David E; Howe, Daniel K

    2005-09-01

    Sarcocystis neurona is the primary causative agent of equine protozoal myeloencephalitis (EPM), a common neurologic disease of horses in the Americas. We have developed a set of enzyme-linked immunosorbent assays (ELISAs) based on the four major surface antigens of S. neurona (SnSAGs) to analyze the equine antibody response to S. neurona. The SnSAG ELISAs were optimized and standardized with a sample set of 36 equine sera that had been characterized by Western blotting against total S. neurona parasite antigen, the current gold standard for S. neurona serology. The recombinant SnSAG2 (rSnSAG2) ELISA showed the highest sensitivity and specificity at 95.5% and 92.9%, respectively. In contrast, only 68.2% sensitivity and 71.4% specificity were achieved with the rSnSAG1 ELISA, indicating that this antigen may not be a reliable serological marker for analyzing antibodies against S. neurona in horses. Importantly, the ELISA antigens did not show cross-reactivity with antisera to Sarcocystis fayeri or Neospora hughesi, two other equine parasites. The accuracy and reliability exhibited by the SnSAG ELISAs suggest that these assays will be valuable tools for examining the equine immune response against S. neurona infection, which may help in understanding the pathobiology of this accidental parasite-host interaction. Moreover, with modification and further investigation, the SnSAG ELISAs have potential for use as immunodiagnostic tests to aid in the identification of horses affected by EPM.

  17. MHC-based detection of antigen-specific CD8(+) T cell responses

    DEFF Research Database (Denmark)

    Hadrup, Sine Reker; Schumacher, Nana Maria Pii

    2010-01-01

    The hallmark of adaptive immunity is its ability to recognise a wide range of antigens and technologies that capture this diversity are therefore of substantial interest. New methods have recently been developed that allow the parallel analysis of T cell reactivity against vast numbers of different...

  18. Altered patterns of gene expression underlying the enhanced immunogenicity of radiation-attenuated schistosomes.

    Directory of Open Access Journals (Sweden)

    Gary P Dillon

    2008-05-01

    Full Text Available Schistosome cercariae only elicit high levels of protective immunity against a challenge infection if they are optimally attenuated by exposure to ionising radiation that truncates their migration in the lungs. However, the underlying molecular mechanisms responsible for the altered phenotype of the irradiated parasite that primes for protection have yet to be identified.We have used a custom microarray comprising probes derived from lung-stage parasites to compare patterns of gene expression in schistosomula derived from normal and irradiated cercariae. These were transformed in vitro and cultured for four, seven, and ten days to correspond in development to the priming parasites, before RNA extraction. At these late times after the radiation insult, transcript suppression was the principal feature of the irradiated larvae. Individual gene analysis revealed that only seven were significantly down-regulated in the irradiated versus normal larvae at the three time-points; notably, four of the protein products are present in the tegument or associated with its membranes, perhaps indicating a perturbed function. Grouping of transcripts using Gene Ontology (GO and subsequent Gene Set Enrichment Analysis (GSEA proved more informative in teasing out subtle differences. Deficiencies in signalling pathways involving G-protein-coupled receptors suggest the parasite is less able to sense its environment. Reduction of cytoskeleton transcripts could indicate compromised structure which, coupled with a paucity of neuroreceptor transcripts, may mean the parasite is also unable to respond correctly to external stimuli.The transcriptional differences observed are concordant with the known extended transit of attenuated parasites through skin-draining lymph nodes and the lungs: prolonged priming of the immune system by the parasite, rather than over-expression of novel antigens, could thus explain the efficacy of the irradiated vaccine.

  19. Antigen detection in vivo after immunization with different presentation forms of rabies virus antigen: Involvement of marginal metallophilic macrophages in the uptake of immune-stimulating complexes

    NARCIS (Netherlands)

    Claassen, I.J.T.M.; Osterhaus, A.D.M.E.; Claassen, E.

    1995-01-01

    Several mechanisms have been postulated to explain the relatively high immunogenicity of antigens presented in immune-stimulating complexes (iscom). Their potency can in part be explained by the specific targeting of these structures to cells presenting antigens to the immune system. However, until

  20. Antigen detection in vivo after immunization with different presentation forms of rabies virus antigen: involvement of marginal metallophilic macrophages in the uptake of immune-stimulating complexes.

    NARCIS (Netherlands)

    I.J.Th.M. Claassen (Ivo); A.D.M.E. Osterhaus (Albert); H.J.H.M. Claassen (Eric)

    1995-01-01

    textabstractSeveral mechanisms have been postulated to explain the relatively high immunogenicity of antigens presented in immune-stimulating complexes (iscom). Their potency can in part be explained by the specific targeting of these structures to cells presenting antigens to the immune system.

  1. Comparison of a stool antigen detection kit and PCR for diagnosis of Entamoeba histolytica and Entamoeba dispar infections in asymptomatic cyst passers in Iran.

    Science.gov (United States)

    Solaymani-Mohammadi, Shahram; Rezaian, Mostafa; Babaei, Zahra; Rajabpour, Azam; Meamar, Ahmad R; Pourbabai, Ahmad A; Petri, William A

    2006-06-01

    The present study was conducted to compare stool antigen detection with PCR for the diagnosis of Entamoeba sp. infection in asymptomatic cyst passers from Iran. Entamoeba dispar and, in one case, E. moshkovskii were the Entamoeba spp. found in the amebic cyst passers. There was a 100% correlation between the results from the TechLab E. histolytica II stool antigen kit and those from nested PCR. We concluded that E. dispar is much more common in asymptomatic cyst passers in Iran and that antigen detection and PCR are comparable diagnostic modalities.

  2. Detection of the circulating antigen 14-3-3 protein of Schistosoma japonicum by time-resolved fluoroimmunoassay in rabbits

    Directory of Open Access Journals (Sweden)

    Wang Jie

    2011-05-01

    Full Text Available Abstract Background Schistosomiasis remains a major public health concern that afflicts millions of people worldwide. Low levels of Schistosoma infection require more sensitive diagnostic methods. In this study, a time-resolved fluoroimmunoassay (TRFIA was developed for detecting the signal transduction protein 14-3-3, a circulating antigen of Schistosoma japonicum. Results The detection limit of 14-3-3-TRFIA was 0.78 ng/ml, with a linear measurement range from 0.78 to 800 ng/ml. The average intra-assay and inter-assay variability of this TRFIA was 8.9% and 12.2% respectively, and the mean recovery rate ranged from 92.1% to 115.5%. Within the first 21 days post-infection in rabbits, the positive rates of the 14-3-3-TRFIA were distinctly higher compared to ELISA. All these findings illustrate that 14-3-3-TRFIA has a higher detection efficacy and is a good early diagnostic method for active Schistosoma infection. Conclusions A sandwich TRFIA for detecting the circulating antigen 14-3-3 of S. japonicum has been developed, and has demonstrated to be a good potential diagnostic method for schistosomiasis.

  3. Application of RNAi to Genomic Drug Target Validation in Schistosomes.

    Directory of Open Access Journals (Sweden)

    Alessandra Guidi

    2015-05-01

    Full Text Available Concerns over the possibility of resistance developing to praziquantel (PZQ, has stimulated efforts to develop new drugs for schistosomiasis. In addition to the development of improved whole organism screens, the success of RNA interference (RNAi in schistosomes offers great promise for the identification of potential drug targets to initiate drug discovery. In this study we set out to contribute to RNAi based validation of putative drug targets. Initially a list of 24 target candidates was compiled based on the identification of putative essential genes in schistosomes orthologous of C. elegans essential genes. Knockdown of Calmodulin (Smp_026560.2 (Sm-Calm, that topped this list, produced a phenotype characterised by waves of contraction in adult worms but no phenotype in schistosomula. Knockdown of the atypical Protein Kinase C (Smp_096310 (Sm-aPKC resulted in loss of viability in both schistosomula and adults and led us to focus our attention on other kinase genes that were identified in the above list and through whole organism screening of known kinase inhibitor sets followed by chemogenomic evaluation. RNAi knockdown of these kinase genes failed to affect adult worm viability but, like Sm-aPKC, knockdown of Polo-like kinase 1, Sm-PLK1 (Smp_009600 and p38-MAPK, Sm-MAPK p38 (Smp_133020 resulted in an increased mortality of schistosomula after 2-3 weeks, an effect more marked in the presence of human red blood cells (hRBC. For Sm-PLK-1 the same effects were seen with the specific inhibitor, BI2536, which also affected viable egg production in adult worms. For Sm-PLK-1 and Sm-aPKC the in vitro effects were reflected in lower recoveries in vivo. We conclude that the use of RNAi combined with culture with hRBC is a reliable method for evaluating genes important for larval development. However, in view of the slow manifestation of the effects of Sm-aPKC knockdown in adults and the lack of effects of Sm-PLK-1 and Sm-MAPK p38 on adult viability

  4. Avoiding false positive antigen detection by flow cytometry on blood cell derived microparticles: the importance of an appropriate negative control.

    Directory of Open Access Journals (Sweden)

    Emerence Crompot

    Full Text Available Microparticles (MPs, also called microvesicles (MVs are plasma membrane-derived fragments with sizes ranging from 0.1 to 1μm. Characterization of these MPs is often performed by flow cytometry but there is no consensus on the appropriate negative control to use that can lead to false positive results.We analyzed MPs from platelets, B-cells, T-cells, NK-cells, monocytes, and chronic lymphocytic leukemia (CLL B-cells. Cells were purified by positive magnetic-separation and cultured for 48h. Cells and MPs were characterized using the following monoclonal antibodies (CD19,20 for B-cells, CD3,8,5,27 for T-cells, CD16,56 for NK-cells, CD14,11c for monocytes, CD41,61 for platelets. Isolated MPs were stained with annexin-V-FITC and gated between 300nm and 900nm. The latex bead technique was then performed for easy detection of MPs. Samples were analyzed by Transmission (TEM and Scanning Electron microscopy (SEM.Annexin-V positive events within a gate of 300-900nm were detected and defined as MPs. Our results confirmed that the characteristic antigens CD41/CD61 were found on platelet-derived-MPs validating our technique. However, for MPs derived from other cell types, we were unable to detect any antigen, although they were clearly expressed on the MP-producing cells in the contrary of several data published in the literature. Using the latex bead technique, we confirmed detection of CD41,61. However, the apparent expression of other antigens (already deemed positive in several studies was determined to be false positive, indicated by negative controls (same labeling was used on MPs from different origins.We observed that mother cell antigens were not always detected on corresponding MPs by direct flow cytometry or latex bead cytometry. Our data highlighted that false positive results could be generated due to antibody aspecificity and that phenotypic characterization of MPs is a difficult field requiring the use of several negative controls.

  5. Detection of autoimmune antibodies in localized scleroderma by synthetic oligonucleotide antigens

    DEFF Research Database (Denmark)

    Samuelsen, Simone; Jørgensen, Christian Damsgaard; Mellins, Elizabeth D

    2018-01-01

    In this study, we developed a series of synthetic oligonucleotides that allowed us to investigate the details on the antigen recognition by autoimmune antibodies in localized scleroderma subjects. Besides dramatically improved analytical specificity of the assay, our data suggests a potential...... linking for antibodies to DNA to the biological status of disease state in localized scleroderma. Moreover, introducing chemical modifications into short synthetic deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) molecules completely changed the binding titers of corresponding antibodies...... and their clinical relevance. The strongest observed effect was registered for the localized scleroderma skin damage index (LoSDI) on the IgG antibodies to TC dinucleotide-rich double-stranded antigen (p

  6. [Recombinant OspC identification and antigenicity detection from Borrelia burgdorferi PD91 in China].

    Science.gov (United States)

    Chen, Jian; Wan, Kang-Lin

    2003-10-01

    To recombine OspC gene from Borrelia burgdorferi PD91 of China and expressed it in E. coli for early diagnosis of Lyme disease. The OspC gene was amplified from the genome of Borrelia burgdorferi PD91 strain by polymerase chain reaction and recombined with plasmid PET-11D. The recombinant plasmid PET-11D-OspC was identified with PCR, restriction endonuclease analysis and sequencing. The antigenicity was verified with Western Blot. OspC gene was cloned correctly into vector PET-11D. The resultant sequence was definitely different from the published sequence. The recombinant OspC seemed to have had strong antigenicity. The findings laid basis for the studies on early diagnosis of Lyme disease.

  7. Simple Objective Detection of Human Lyme Disease Infection Using Immuno-PCR and a Single Recombinant Hybrid Antigen

    Science.gov (United States)

    Halpern, Micah D.; Molins, Claudia R.; Schriefer, Martin

    2014-01-01

    A serology-based tiered approach has, to date, provided the most effective means of laboratory confirmation of clinically suspected cases of Lyme disease, but it lacks sensitivity in the early stages of disease and is often dependent on subjectively scored immunoblots. We recently demonstrated the use of immuno-PCR (iPCR) for detecting Borrelia burgdorferi antibodies in patient serum samples that were positive for Lyme disease. To better understand the performance of the Lyme disease iPCR assay, the repeatability and variability of the background of the assay across samples from a healthy population (n = 36) were analyzed. Both of these parameters were found to have coefficients of variation of Lyme disease patient serum samples (n = 12) demonstrated a strong correlation with that of 2-tier testing. Furthermore, a simplified iPCR approach using a single hybrid antigen and detecting only IgG antibodies confirmed the 2-tier diagnosis in the Lyme disease patient serum samples (n = 12). Validation of the hybrid antigen IgG iPCR assay using a blinded panel of Lyme disease and non-Lyme disease patient serum samples (n = 92) resulted in a sensitivity of 69% (95% confidence interval [CI], 50% to 84%), compared to that of the 2-tier analysis at 59% (95% CI, 41% to 76%), and a specificity of 98% (95% CI, 91% to 100%) compared to that of the 2-tier analysis at 97% (95% CI, 88% to 100%). A single-tier hybrid antigen iPCR assay has the potential to be an improved method for detecting host-generated antibodies against B. burgdorferi. PMID:24899074

  8. IMPROVEMENT OF SCHISTOSOMAL PORTAL HYPERTENSIVE COLOPATHY AFTER SURGICAL TREATMENT

    Directory of Open Access Journals (Sweden)

    Maria Angelina Carvalho MIRANDA

    2013-04-01

    Full Text Available Context Data on vascular alterations in patients with hepatosplenic schistosomiasis and portal hypertensive colopathy and changes in these after surgery to decrease portal hypertension are limited. Objective The purpose of this study was to analyse the alterations of portal hypertensive colopathy previously and 6-12 months after splenectomy and gastric devascularization. Methods Twelve patients with hepatosplenic schistosomiasis who also had upper gastrointestinal bleeding were studied prospectively. Their endoscopic findings before and 6-12 months after the surgery were analysed. In addition, mucosal biopsies from ascending colon, sigmoid colon and rectum at these time points were subjected to histological and histomorphometric assessment. It was used a control group due to lack of normal pattern of the histomorphometric measures of vessels in individuals without portal hypertension. The critical level of significance adopted in all tests was of a maximum probability error of 5%. Results Surgery did not lead to significant improvement in histological and endoscopic findings. However, on histomorphometry, there was a significant decrease in the area, diameter and thickness of the vessels in mucosa at all colonic sites. Conclusion Surgery for decompression of schistosomal portal hypertension has a beneficial effect on the associated colopathy, being best indicated in patients with gastrointestinal bleeding and esophageal varices.

  9. A novel dendritic cell-based direct ex vivo assay for detection and enumeration of circulating antigen-specific human T cells.

    Science.gov (United States)

    Carrio, Roberto; Zhang, Ge; Drake, Donald R; Schanen, Brian C

    2018-05-07

    Although a variety of assays have been used to examine T cell responses in vitro, standardized ex vivo detection of antigen-specific CD4 + T cells from human circulatory PBMCs remains constrained by low-dimensional characterization outputs and the need for polyclonal, mitogen-induced expansion methods to generate detectable response signals. To overcome these limitations, we developed a novel methodology utilizing antigen-pulsed autologous human dendritic target cells in a rapid and sensitive assay to accurately enumerate antigen-specific CD4 + T cell precursor frequency by multiparametric flow cytometry. With this approach, we demonstrate the ability to reproducibly quantitate poly-functional T cell responses following both primary and recall antigenic stimulation. Furthermore, this approach enables more comprehensive phenotypic profiling of circulating antigen-specific CD4 + T cells, providing valuable insights into the pre-existing polarization of antigen-specific T cells in humans. Combined, this approach permits sensitive and detailed ex vivo detection of antigen-specific CD4 + T cells delivering an important tool for advancing vaccine, immune-oncology and other therapeutic studies.

  10. Use of an immunodominant p17 antigenic fraction of Neospora caninum in detection of antibody response in cattle

    Directory of Open Access Journals (Sweden)

    Gema Álvarez García

    2006-08-01

    Full Text Available A Neospora caninum 17 kDa protein fraction (p17 has been described as an immunodominant antigen (IDA under reducing and non-reducing conditions. The aim of the present study was to investigate the diagnostic utility of p17 in cattle. In order to achieve this, p17 was purified by electroelution from whole N. caninum tachyzoite soluble extract and a p17-based Western blot (WB-p17 was developed. The p17 recognition was measured by densitometry and expressed as OD values to check the validity of the WB-p17. A total of 131 sera including sequential samples from naturally- and experimentally-infected calves and breeding cattle were analysed by WB-p17 and compared with IFAT using whole formalin-fixed tachyzoites as a reference test. The results obtained highlight the feasibility of using the N. caninum p17 in a diagnostic test in cattle. Firstly, the assay based on the p-17 antigen discriminated between known positive and negative sera from different cattle populations, breeding cattle and calves. Secondly, the p17 antigen detected fluctuations in the antibody levels and seroconversion in naturally- and experimentally-infected cattle. Significant differences in p-17 antigen recognition were observed between naturally infected aborting and non-aborting cattle, as well as significant antibody fluctuations over time in experimentally infected cattle, which varied between groups. Furthermore, the results obtained with WB-p17 are in accordance with the results obtained with the IFAT, as high agreement values were obtained when all bovine subpopulations were included (kappa = 0.86.

  11. Detection of survivin, carcinoembryonic antigen and ErbB2 level in oral squamous cell carcinoma patients.

    Science.gov (United States)

    Li, Shu-Xia; Yang, Yan-Qi; Jin, Li-Jian; Cai, Zhi-Gang; Sun, Zheng

    2016-01-01

    The aim of this study was to detect the survivin, carcinoembryonic antigen (CEA) and ErbB2 in the saliva, serum and local tumor-exfoliated cells of oral squamous cell carcinoma (OSCC) patients, for providing reliable tumor markers for the early detection of oral malignant cancer. The saliva, serum, and local tumor-exfoliated cell samples of 26 OSCC patients without chemotherapy and 10 non-cancer patients were collected in Department of Oral and Maxillofacial Surgery, School of Stomatology, Peking University. The contents of survivin, CEA and ErbB2 using were detected usingenzyme-linked immunosorbent assay. The survivin and CEA levels in saliva and local tumor-exfoliated cells of OSCC patients were significantly higher than those in the non-cancer patients (P oral malignant cancer.

  12. The simultaneous ex vivo detection of low-frequency antigen-specific CD4+ and CD8+ T-cell responses using overlapping peptide pools.

    Science.gov (United States)

    Singh, Satwinder Kaur; Meyering, Maaike; Ramwadhdoebe, Tamara H; Stynenbosch, Linda F M; Redeker, Anke; Kuppen, Peter J K; Melief, Cornelis J M; Welters, Marij J P; van der Burg, Sjoerd H

    2012-11-01

    The ability to measure antigen-specific T cells at the single-cell level by intracellular cytokine staining (ICS) is a promising immunomonitoring tool and is extensively applied in the evaluation of immunotherapy of cancer. The protocols used to detect antigen-specific CD8+ T-cell responses generally work for the detection of antigen-specific T cells in samples that have undergone at least one round of in vitro pre-stimulation. Application of a common protocol but now using long peptides as antigens was not suitable to simultaneously detect antigen-specific CD8+ and CD4+ T cells directly ex vivo in cryopreserved samples. CD8 T-cell reactivity to monocytes pulsed with long peptides as antigens ranged between 5 and 25 % of that observed against monocytes pulsed with a direct HLA class I fitting minimal CTL peptide epitope. Therefore, we adapted our ICS protocol and show that the use of tenfold higher concentration of long peptides to load APC, the use of IFN-α and poly(I:C) to promote antigen processing and improve T-cell stimulation, does allow for the ex vivo detection of low-frequency antigen-specific CD8+ and CD4+ T cells in an HLA-independent setting. While most of the improvements were related to increasing the ability to measure CD8+ T-cell reactivity following stimulation with long peptides to at least 50 % of the response detected when using a minimal peptide epitope, the final analysis of blood samples from vaccinated patients successfully showed that the adapted ICS protocol also increases the ability to ex vivo detect low-frequency p53-specific CD4+ T-cell responses in cryopreserved PBMC samples.

  13. c-KIT positive schistosomal urinary bladder carcinoma are frequent but lack KIT gene mutations.

    Science.gov (United States)

    Shams, Tahany M; Metawea, Mokhtar; Salim, Elsayed I

    2013-01-01

    Urinary bladder squamous cell carcinoma (SCC), one of the most common neoplasms in Egypt, is attributed to chronic urinary infection with Schistosoma haematobium (Schistosomiasis). The proto-oncogene c-KIT, encoding a tyrosine kinase receptor and implicated in the development of a number of human malignancies, has not been studied so far in schistosomal urinary bladder SCCs. We therefore determined immunohistochemical (IHC) expression of c-KIT in paraffin sections from 120 radical cystectomies of SCCs originally obtained from the Pathology Department of Suez Canal University (Ismailia, Egypt). Each slide was evaluated for staining intensity where the staining extent of >10% of cells was considered positive. c-KIT overexpression was detected in 78.3% (94/120) of the patients, the staining extents in the tumor cells were 11-50% and >50% in 40 (42.6%) and 54 (57.4%) respectively. The positive cases had 14.9%, 63.8%, 21.3% as weak, moderate and strong intensity respectively. Patients with positive bilharzial ova had significantly higher c-KIT expression than patients without (95.2% vs. 38.9%, P=0.000). Mutation analysis of exons 9-13 was negative in thirty KIT positive cases. The high rate of positivity in SBSCC was one of the striking findings; However, CD117 may be a potential target for site specific immunotherapy to improve the outcome of this tumor.

  14. Generation of monoclonal antibodies against prostate specific antigen (PSA) for the detection of PSA and its purification

    International Nuclear Information System (INIS)

    Acevedo Castro, Boris Ernesto

    2012-01-01

    The prostate cancer in Cuba is a problem of health (2672 diagnosed cases and 2769 deaths in 2007). Various diagnostic methods have been implemented for the detection and management of this disease, emphasizing among them (PSA) prostate-specific antigen serological determination. At this work was generated and characterized a panel of 11 antibodies (AcMs) monoclonal IgG1 detected with high affinity described major epitopes of the PSA, both in solution and attached to the test plate. From the panel obtained AcMs was the standardization of an essay type ELISA for the detection of serum total PSA (associated and free) equimolar, based on antibody monoclonal CB-PSA.4 in the coating and the CB-PSA.9 coupled with biotin as liner, with a detection limit of 0.15 ng/mL. Similarly, standardized system for detection in serum free PSA, based on the AcMs CB-PSA.4 (coating) and CB-PSA.2 coupled with biotin (liner), with a detection limit of 0.5 ng/mL. Finally, with the purpose of using PSA as standard in trials type ELISA, developed a simple method of inmunopurificación based on the AcM, CB-PSA.2, which was obtained the PSA with a purity exceeding 90%. Immunoassay Centre on the basis of the AcMs panel and the results of this study, developed and recorded two diagnostic systems for the detection of PSA in human serum. (author)

  15. Chimeric antigen receptor (CAR-specific monoclonal antibody to detect CD19-specific T cells in clinical trials.

    Directory of Open Access Journals (Sweden)

    Bipulendu Jena

    Full Text Available Clinical trials targeting CD19 on B-cell malignancies are underway with encouraging anti-tumor responses. Most infuse T cells genetically modified to express a chimeric antigen receptor (CAR with specificity derived from the scFv region of a CD19-specific mouse monoclonal antibody (mAb, clone FMC63. We describe a novel anti-idiotype monoclonal antibody (mAb to detect CD19-specific CAR(+ T cells before and after their adoptive transfer. This mouse mAb was generated by immunizing with a cellular vaccine expressing the antigen-recognition domain of FMC63. The specificity of the mAb (clone no. 136.20.1 was confined to the scFv region of the CAR as validated by inhibiting CAR-dependent lysis of CD19(+ tumor targets. This clone can be used to detect CD19-specific CAR(+ T cells in peripheral blood mononuclear cells at a sensitivity of 1∶1,000. In clinical settings the mAb is used to inform on the immunophenotype and persistence of administered CD19-specific T cells. Thus, our CD19-specific CAR mAb (clone no. 136.20.1 will be useful to investigators implementing CD19-specific CAR(+ T cells to treat B-lineage malignancies. The methodology described to develop a CAR-specific anti-idiotypic mAb could be extended to other gene therapy trials targeting different tumor associated antigens in the context of CAR-based adoptive T-cell therapy.

  16. Development of a immunochromatographic test with avidin-biotin for the detection of antibodies against antigen e of hepatitis B in human plasma

    International Nuclear Information System (INIS)

    Mainet Gonzalez, Damian; Palenzuela Gardon, Daniel O; Diaz Argudin, Tamara

    2007-01-01

    The disappearance of antigen e of hepatitis B in the presence of the plasmatic antibodies against antigen e may indicate a satisfactory therapeutic response in patients with chronic hepatitis B. The immuno-chromatographic test carried out in the diagnosis of diseases use different antibody combinations and may employ the avidin or streptavidin-biotin technology to develop a rapid immuno-chromatographic test for the detection of antibodies anti-antigen e in the plasma. They were detected in the laboratory by means of two fast immuno-chromatographic tests when using in one of them the avidin-biotin technology. These tests are carried out with a one-step competitive inhibition format and amplified or not with avidin-biotin. Monoclonal antibodies against antigen e obtained by cellular hybridization were used. Forty-six plasmatic samples classified as positive and negative to the anti-antigen antibodies were evaluated with a reference immunochromatographic test Advanced QualityTM. The possible expiry time of the biological reagents forming part of these tests were studied with accelerated thermal-stability experiments. The possible interference in the plasma of some of the biochemical compounds used in these trials was analyzed. Four murine monoclonal antibodies anti-antigen e were obtained and only one of them was used in these immunochromatographic tests with an anti-antigen polyclonal antibody conjugated with gold. Both tests and their stable biological reagents discriminated the positive and negative samples to the antibodies anti-antigen e, as well as the commercial test. There was no interference in the biochemical compounds studied in these tests. Both immuno-chromatographic tests made in the laboratory are useful to detect antibodies anti-antigen e in the plasma. The avidin-biotin increased the analytical sensitivity of this type of fast immuno-chromatographic test without altering its performance features. (Author)

  17. New technology for regiospecific covalent coupling of polysaccharide antigens in ELISA for serological detection

    DEFF Research Database (Denmark)

    Jauho, E.S.; Boas, Ulrik; Wiuff, Camilla

    2000-01-01

    In this study we demonstrate a new UV irradiation technique for covalent coupling of bacterial polysaccharides derived from lipopolysaccharides to microtiter plates and the use of such plates in an enzyme linked immunosorbent assay (ELISA). Lipopolysaccharides were cleaved by mild acid hydrolysis...... describe the use of this technique for the immobilization of Lipopolysaccharide derived polysaccharides from Salmonella Typhimurium and Salmonella Choleraesuis lipopolysaccharides, representing the O-antigens 1, 4, 5, 6, 7, and 12, The functional polysaccharide surface gave similar ELISA results to plates...

  18. Application of 125I-labelled soluble proteins in the histoautoradiographic detection of antigen and antibodies in the spleen of rabbits during primary immune response

    International Nuclear Information System (INIS)

    Rodak, L.

    1975-01-01

    An autoradiographic method for detecting soluble antigen (chicken serum albumin, CSA) and specific antibodies in the spleen of rabbits during a primary immune response is described. The method consists of incubating sections from the spleen with 125 I-labelled IgG 2 anti CSA (for demonstration of antigen) or with 125 I-labelled antigen (for demonstration of specific antibodies). This treatment of histological sections combines the advantages and principles of the immunofluorescence technique with the possibility of evaluating the exact localization of the proteins by light microscopy in preparations stained with haematoxylin or methyl green-pyronin. The sensitivity of detection is very high: both antigen and antibodies could be demonstrated in the spleen follicles for as long as 42 days after the primary intravenous injection

  19. Enzyme linked immunosorbent assay for detecting antibody to Trichomonas vaginalis: use of whole cells and aqueous extract as antigen.

    Science.gov (United States)

    Alderete, J F

    1984-06-01

    An enzyme linked immunosorbent assay (ELISA) for detecting antibody to antigenic Trichomonas vaginalis macromolecules has been identified using whole cells or an aqueous protein extract as antigen. The test was developed under optimum conditions using serum samples from experimental animals. The sensitivity of the ELISA was equal to or greater than that obtained by radioimmunoprecipitation and electrophoresis-fluorography techniques. The ELISA was capable of assessing antibody responses during the development of lesions in animals inoculated subcutaneously and it reproducibly measured the individual classes immunoglobulins directed at T vaginalis. The colorimetric assay was also suitable for showing cross reactivity between trichomonal species as well as between different strains of T vaginalis. Conditions established for monitoring antibody to trichomanads in immunised rabbits or infected mice were equally effective for human materials, such as serum or vaginal washes. Serum from experimental animals or infected people showed high concentrations of IgG, IgA, and IgM antibody to trichomonads. Only antibodies of the IgG and IgA class were detected in vaginal washes from women with acute trichomoniasis. No IgE antibody to trichomonads was found under a variety of conditions in serum samples from patients or experimental animals.

  20. Detection of antibodies to the extractable nuclear antigens by enzyme linked immunosorbent assay

    International Nuclear Information System (INIS)

    Aziz, Khalil A.; Fzizal, Abul A.

    2005-01-01

    Anti-extractable nuclear antigen (ENA) antibodies are a group of autoantibodies that are directed against various components of the cell nucleus. Antibodies to these antigens are closely associated with connective tissue disease. Early diagnosis of these diseases can prove very difficult and therefore clinicians rely on the use of anti-ENA antibody testing for the exclusion. Old methods of testing are time consuming and require great skills. For these reasons clinical immunology laboratories are switching to testing for anti-ENA antibodies by enzyme linked immunosorbent assay (ELISA). The latter assays are more sensitive and require little skills. In the present study we have investigated a number of different ELISA preparations. The study was conducted at Birmingham Heartlands Hospital during the period 2003. We tested a number of ENA-positive and negative samples using 3 different commercial ELISA preparations and compared the results with traditional CCIE-assay. The present study revealed that some ELISA preparations can be more sensitive than CCIE method. Laboratories still using later method should switch to ELISA. However it is important that laboratories evaluate a long range of different ELISA preparations before selecting the most optimal one. In addition it is recommended that laboratories then audit results in order to determine true significance of such results. Finally until the true significance of ELISA generated results is known, positive ENA-results should be interpreted in conjunction with the clinical picture and this would require close liaison in between the clinical immunology laboratory and clinicians

  1. Prostate-specific membrane antigen PET/MRI validation of MR textural analysis for detection of transition zone prostate cancer.

    Science.gov (United States)

    Bates, Anthony; Miles, Kenneth

    2017-12-01

    To validate MR textural analysis (MRTA) for detection of transition zone (TZ) prostate cancer through comparison with co-registered prostate-specific membrane antigen (PSMA) PET-MR. Retrospective analysis was performed for 30 men who underwent simultaneous PSMA PET-MR imaging for staging of prostate cancer. Thirty texture features were derived from each manually contoured T2-weighted, transaxial, prostatic TZ using texture analysis software that applies a spatial band-pass filter and quantifies texture through histogram analysis. Texture features of the TZ were compared to PSMA expression on the corresponding PET images. The Benjamini-Hochberg correction controlled the false discovery rate at prostate cancer. • Prostate transition zone (TZ) MR texture analysis may assist in prostate cancer detection. • Abnormal transition zone PSMA expression correlates with altered texture on T2-weighted MR. • TZ with abnormal PSMA expression demonstrates significantly reduced MI, SD and MPP.

  2. [Diagnostic advantages of the test system "DS-EIA-HBsAg-0.01" for detection of HBV surface antigen].

    Science.gov (United States)

    Egorova, N I; Pyrenkova, I Iu; Igolkina, S N; Sharipova, I N; Puzyrev, V F; Obriadina, A P; Burkov, A N; Kornienko, N V; Fields, H A; Korovkin, A S; Shalunova, N V; Bektemirov, T A; Kuznetsov, K V; Koshcheeva, N A; Ulanova, T I

    2009-01-01

    The new highly sensitive test system "DS-EIA-HBsAg-0.01" (Priority Certificate No. 2006129019 of August 10, 2006) in detecting hepatitis B surface antigen (HBsAg) was assessed. The sensitivity of the test was estimated using the federal standards sample HBsAg 42-28-311-06, panels' samples Boston Biomedica Inc. (West Bridgewater, Mass, USA) and ZeptoMetrix Corp. (Buffalo, NY, USA). The findings have indicated that "DS-EIA-HBsAg-0.01" is equally effective in detecting different subtypes of HBsAg during a seroconversion period earlier than alternative assays. Along with its high analytical and diagnostic sensitivity, the system shows a high diagnostic specificity.

  3. Immunolocalization of Schistosoma mansoni and Schistosoma haematobium antigens reacting with their Egyptian snail vectors.

    Science.gov (United States)

    El-Dafrawy, Shadia M; Mohamed, Amira H; Hammam, Olfat A; Rabia, Ibrahim

    2007-12-01

    The reaction of the haemolymph and the tissue of infected intermediate hosts, Biomphalaria alexandrina and Bulinus truncatus to Schistosoma mansoni and S. haematobium antigens were investigated using the indirect immunoperoxidase technique. A new technique, Agarose cell block was used in collection of haemolymph which helped in collecting plenty of well formed cells in comparison to the ordinary one using the cytospin. Collected haemolymph and prepared tissues of uninfected and infected B. alexandria and B. truncatus were fixed and then reacted with anti-S. mansoni and anti-S. haematobium IgG polyclonal antibodies. The haemolymph and tissue of infected B. alexandrina and B. truncatus gave a positive peroxidase reaction represented by a brown colour. In haemolymph, the positive peroxidase reaction was detected mainly in the cytoplasm of the amoebocytes. In the tissue, it was detected in epithelial cells lining the tubules, male cells in the lumen of the tubules and in female oogonia cells along the periphery of the tubules. The similarity in the strength and distribution of positive reaction in B. alexandrina and B. truncates was observed as compared to control. Thus, the immunoperoxidase technique proved to be an effective indicator for the schistosome-antigen in the snails.

  4. Inhibition or knockdown of ABC transporters enhances susceptibility of adult and juvenile schistosomes to Praziquantel.

    Directory of Open Access Journals (Sweden)

    Ravi S Kasinathan

    2014-10-01

    Full Text Available Parasitic flatworms of the genus Schistosoma cause schistosomiasis, a neglected tropical disease that affects hundreds of millions. Treatment of schistosomiasis depends almost entirely on the drug praziquantel (PZQ. Though essential to treating and controlling schistosomiasis, a major limitation of PZQ is that it is not active against immature mammalian-stage schistosomes. Furthermore, there are reports of field isolates with heritable reductions in PZQ susceptibility, and researchers have selected for PZQ-resistant schistosomes in the laboratory. P-glycoprotein (Pgp; ABCB1 and other ATP binding cassette (ABC transporters remove a wide variety of toxins and xenobiotics from cells, and have been implicated in multidrug resistance (MDR. Changes in ABC transporter structure or expression levels are also associated with reduced drug susceptibility in parasitic helminths, including schistosomes. Here, we show that the activity of PZQ against schistosome adults and juveniles ex vivo is potentiated by co-administration of either the highly potent Pgp inhibitor tariquidar or combinations of inhibitors targeting multiple ABC multidrug transporters. Adult worms exposed to sublethal PZQ concentrations remain active, but co-administration of ABC transporter inhibitors results in complete loss of motility and disruption of the tegument. Notably, juvenile schistosomes (3-4 weeks post infection, normally refractory to 2 µM PZQ, become paralyzed when transporter inhibitors are added in combination with the PZQ. Experiments using the fluorescent PZQ derivative (R-PZQ-BODIPY are consistent with the transporter inhibitors increasing effective intraworm concentrations of PZQ. Adult worms in which expression of ABC transporters has been suppressed by RNA interference show increased responsiveness to PZQ and increased retention of (R-PZQ-BODIPY consistent with an important role for these proteins in setting levels of PZQ susceptibility. These results indicate that

  5. Antigen-Dissociation from Antibody-Modified Nanotransistor Sensor Arrays as a Direct Biomarker Detection Method in Unprocessed Biosamples.

    Science.gov (United States)

    Krivitsky, Vadim; Zverzhinetsky, Marina; Patolsky, Fernando

    2016-10-12

    The detection of biomolecules is critical for a wide spectrum of applications in life sciences and medical diagnosis. Nonetheless, biosamples are highly complex solutions, which contain an enormous variety of biomolecules, cells, and chemical species. Consequently, the intrinsic chemical complexity of biosamples results in a significant analytical background noise and poses an immense challenge to any analytical measurement, especially when applied without prior efficient separation and purification steps. Here, we demonstrate the application of antigen-dissociation regime, from antibody-modified Si-nanowire sensors, as a simple and effective direct sensing mechanism of biomarkers of interest in complex biosamples, such as serum and untreated blood, which does not require ex situ time-consuming biosample manipulation steps, such as centrifugation, filtering, preconcentration, and desalting, thus overcoming the detrimental Debye screening limitation of nanowire-based biosensors. We found that two key parameters control the capability to perform quantitative biomarkers analysis in biosamples: (i) the affinity strength (k off rate) of the antibody-antigen recognition pair, which dictates the time length of the high-affinity slow dissociation subregime, and (ii) the "flow rate" applied during the solution exchange dissociation step, which controls the time width of the low-affinity fast-dissociation subregime. Undoubtedly, this is the simplest and most convenient approach for the SiNW FET-based detection of antigens in complex untreated biosamples. The lack of ex situ biosample manipulation time-consuming processes enhances the portability of the sensing platform and reduces to minimum the required volume of tested sample, as it allows the direct detection of untreated biosamples (5-10 μL blood or serum), while readily reducing the detection cycle duration to less than 5 min, factors of great importance in near-future point-of-care medical applications. We believe

  6. Evaluation of enzyme-linked immunosorbent assays based on monoclonal antibodies for the serology and antigen detection in canine parvovirus infections.

    NARCIS (Netherlands)

    G.F. Rimmelzwaan (Guus); N. Juntti; B. Klingeborn; J. Groen (Jan); F.G.C.M. Uytdehaag (Fons); A.D.M.E. Osterhaus (Albert)

    1990-01-01

    textabstractAn enzyme-linked immunosorbent assay (ELISA) system was developed for the detection of canine parvovirus (CPV) or CPV antigen in dog faeces and two other ELISA systems were developed for the detection of CPV-specific antibodies in dog sera. The ELISA's were based on the use of

  7. Love Wave Sensor for Prostate-Specific Membrane Antigen Detection Based on Hydrophilic Molecularly-Imprinted Polymer

    Directory of Open Access Journals (Sweden)

    Pingping Tang

    2018-05-01

    Full Text Available Prostate-specific membrane antigen (PSMA is a biomarker for prostate cancer (PCa, and a specific and reliable detection technique of PSMA is urgently required for PCa early diagnosis. A Love wave sensor has been widely studied for real-time sensing and highly sensitive applications, but the sensing unit needs special handling for selective detection purpose. In this study, we prepared a versatile Love wave sensor functionalized with molecularly-imprinted polymers (MIP, PSMA as the template molecule. To enhance the specific template bindings of MIP in pure aqueous solutions, facile reversible addition/fragmentation chain transfer (RAFT precipitation polymerization (RAFTPP was used to produce surface hydrophilic polymer brushes on MIP. The presence of hydrophilic polymer brushes on MIP improved its surface hydrophilicity and significantly reduced their hydrophobic interactions with template molecules in pure aqueous media. In detection process, the acoustic delay-line is confederative to a microfluidic chip and inserted in an oscillation loop. The real-time resonance frequency of the MIP-based Love wave sensor to different concentrations of PSMA was investigated. The limit of detection (LOD for this Love SAW sensor was 0.013 ng mL−1, which demonstrates that this sensor has outstanding performance in terms of the level of detection.

  8. A nanoparticle label/immunochromatographic electrochemical biosensor for rapid and sensitive detection of prostate-specific antigen

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Ying-Ying; Wang, Jun; Liu, Guodong; Wu, Hong; Wai, Chien M.; Lin, Yuehe

    2008-06-15

    We present a nanoparticle (NP) label/immunochromatographic electrochemical biosensor (IEB) for rapid and sensitive detection of prostate-specific antigen (PSA) in human serum. This IEB integrates the immunochromatographic strip with the electrochemical detector for transducing quantitative signals. The NP label, made of CdSe@ZnS, serves as a signal-amplifier vehicle. A sandwich immunoreaction was performed on the immunochromatographic strip. The captured NP labels in the test zone were determined by highly sensitive stripping voltammetric measurement of the dissolved metallic component (cadmium) with a disposable-screen-printed electrode, which is embedded underneath the membrane of the test zone. Experimental parameters (e.g., immunoreaction time, the amount of anti-PSA-NP conjugations applied) and electrochemical detection conditions (e.g., preconcentration potential and time) were optimized using this biosensor for PSA detection. The analytical performance of this biosensor was evaluated with serum PSA samples according to the “figure-of-merits” (e.g., dynamic range, reproducibility, and detection limit). The results were validated with enzyme-linked immunosorbent assay (ELISA) and show high consistency. It is found that this biosensor is very sensitive with the detection limit of 0.02 ng/mL PSA and is quite reproducible. This method is rapid, clinically accurate, and less expensive than other diagnosis tools for PSA; therefore, this IEB coupled with a portable electrochemical analyzer shows great promise for simple, sensitive, quantitative point-of-care testing of disease-related protein biomarkers.

  9. Detection of Potentially Diagnostic Leishmania Antigens with Western Blot Analysis of Sera from Patients with Cutaneous and Visceral Leishmaniases

    Directory of Open Access Journals (Sweden)

    Seyyed Javad SEYYEDTABAEI

    2017-06-01

    Full Text Available Background: Visceral leishmaniasis (VL and cutaneous leishmaniasis (CL are important public health problems in Iran. We aimed to evaluate the diagnostic potential of Western blot (WB compared with indirect immunofluorescence test (IFAT to serodiagnosis of leishmaniasis.Methods: This study was performed from 2010-2014 and participants were different parts of Iran. Serum samples were obtained from 43 patients with proven CL, 33 patients with proven VL, 39 patients with other parasitic diseases and 23 healthy individuals. Results: WB sensitivity for CL and VL was 100% and 91%, compared to IFA 4.6% and 87.8%, respectively. Sera from patients with CL and VL recognized numerous antigens with molecular weights ranging from 14 to 68 kDa and 12 to 94 kDa, respectively. The most sensitive antigens were 14 and 16 kDa for CL recognized by 100% of the sera from patients with proven CL and 12, 14 and 16 kDa for VL, recognized by 63.6%, 100% and 63.6% of the sera from patients with proven VL respectively. WB analysis is more sensitive than IFAT for the diagnosis of leishmaniasis particularly in cases of cutaneous leishmaniasis. The 12, 14 and 16 kDa can be valuable diagnostic molecules for serodiagnosis of leishmaniasis because at least two immunogenic molecules were simultaneously detected by all patient sera, as well as produced antibodies against these antigens have no cross-reactivity with other control groups.Conclusion: WB could be useful for screening and serodiagnosis of CL and VL in epidemiologic studies in endemic areas.

  10. Using a genomic assay for the detection of SNPs of Knops blood group antigens leads to the identification of two caucasians homozygous for the SNP associated with the knops SL3 antigen

    DEFF Research Database (Denmark)

    Jakobsen, M. A.; Sprogoe, U.

    2015-01-01

    designed a genomic assay based on sequencing targeting the SNPs underlying the antigens of the Knops system. Study Design/Methods: Samples from a total of 105 blood donors and 2 patients were examined for polymorphisms in CR1 exon 29 by using PCR and subsequent Sanger sequencing. Results......Background/Case Studies: The antigens of the Knops (Kn) blood group system are associated with SNPs located on exon 29 and (to lesser extent) on exon 26 of the complement receptor 1 (CR1) gene. Because of a lack of proper typing antibodies, serologic detection of Kn antigens is not feasible. We....../Findings: With regard to Kn a and b antigens, we found SNP frequencies to be 90.5% for G/G (4681)* associated with Kn(a+b-) and 9.5% for G/A associated with Kn(a+b+). None of the 107 patients/donors were found to be homozygous for A/A associated with Kn(ab+). The frequencies of SNPs associated with the KCAM antigen...

  11. A self-amplified transistor immunosensor under dual gate operation: highly sensitive detection of hepatitis B surface antigen

    Science.gov (United States)

    Lee, I.-K.; Jeun, M.; Jang, H.-J.; Cho, W.-J.; Lee, K. H.

    2015-10-01

    Ion-sensitive field-effect transistors (ISFETs), although they have attracted considerable attention as effective immunosensors, have still not been adopted for practical applications owing to several problems: (1) the poor sensitivity caused by the short Debye screening length in media with high ion concentration, (2) time-consuming preconditioning processes for achieving the highly-diluted media, and (3) the low durability caused by undesirable ions such as sodium chloride in the media. Here, we propose a highly sensitive immunosensor based on a self-amplified transistor under dual gate operation (immuno-DG ISFET) for the detection of hepatitis B surface antigen. To address the challenges in current ISFET-based immunosensors, we have enhanced the sensitivity of an immunosensor by precisely tailoring the nanostructure of the transistor. In the pH sensing test, the immuno-DG ISFET showed superior sensitivity (2085.53 mV per pH) to both standard ISFET under single gate operation (58.88 mV per pH) and DG ISFET with a non-tailored transistor (381.14 mV per pH). Moreover, concerning the detection of hepatitis B surface antigens (HBsAg) using the immuno-DG ISFET, we have successfully detected trace amounts of HBsAg (22.5 fg mL-1) in a non-diluted 1× PBS medium with a high sensitivity of 690 mV. Our results demonstrate that the proposed immuno-DG ISFET can be a biosensor platform for practical use in the diagnosis of various diseases.Ion-sensitive field-effect transistors (ISFETs), although they have attracted considerable attention as effective immunosensors, have still not been adopted for practical applications owing to several problems: (1) the poor sensitivity caused by the short Debye screening length in media with high ion concentration, (2) time-consuming preconditioning processes for achieving the highly-diluted media, and (3) the low durability caused by undesirable ions such as sodium chloride in the media. Here, we propose a highly sensitive immunosensor

  12. Detection rate of prostate cancer using prostate specific antigen in patients presenting with lower urinary tract symptoms: A retrospective study

    Directory of Open Access Journals (Sweden)

    Chavan P

    2009-01-01

    Full Text Available Background: Need for undertaking prostate biopsies for detection of prostate cancer is often decided on the basis of serum levels of prostate specific antigen (PSA. Aim: To evaluate the case detection rate of prostate cancer among patients presenting with lower urinary tract symptoms (LUTS on the basis of PSA levels and to assess the scope of prostate biopsy in these patients. Setting and Design: A retrospective study from a tertiary care center. Materials and Methods: The clinical and histopathological data of 922 patients presenting with LUTS in the last five years was obtained from the medical record section. They had been screened for prostate cancer using PSA and /or digital rectal examination examination followed by confirmation with prostate biopsy. Statistical Analysis Used: Detection rate and receiver operating characteristic curve were performed using SPSS 16 and Medcalc softwares. Results: The detection rate of prostate cancer according to the PSA levels was 0.6%, 2.3%, 2.5%, 34.1% and 54.9% in the PSA range of 0-4, 4-10, 10-20, 20-50 and> 50 ng/ml, respectively. Maximum prostate cancer cases were detected beyond a PSA value of 20 ng/ml whereas no significant difference in the detection rate was observed in the PSA range of 0-4, 4-10 and 10-20 ng/ml. Conclusion: A low detection rate of prostate cancer observed in the PSA range of 4-20 ng/ml in LUTS patients indicates the need for use of higher cutoff values of PSA in such cases. Therefore we recommend a cutoff of 20 ng/ml of PSA for evaluation of detection rate of prostate cancer among patients presenting with LUTS.

  13. Evaluation of a Direct Immunofluorescent Assay and/or Conjunctival Cytology for Detection of Canine Distemper Virus Antigen.

    Science.gov (United States)

    Athanasiou, Labrini V; Kantere, Maria C; Kyriakis, Constantinos S; Pardali, Dimitra; Adamama Moraitou, Katerina; Polizopoulou, Zoe S

    2018-04-01

    Canine distemper is a common and potentially lethal multisystemic disease caused by the Canine distemper virus (CDV). We evaluated the diagnostic performance of direct immunofluorescent assay (FA) and cytology to detect CDV antigen in conjunctival cells compared with an established polymerase chain reaction (PCR) detection assay used as a gold standard for CDV diagnosis. Samples were collected from 57 young dogs presenting with central nervous system signs compatible with distemper disease. Exfoliative epithelial cells were collected from the right and left conjunctiva of each animal using nylon-bristled cytobrushes for cytology and cotton swabs for FA and PCR. For the direct FA, samples were stained with anti-CDV polyclonal antiserum conjugated to fluorescein isothiocyanate and imaged using a fluorescent microscope. Out of 57 dogs tested, 19 were PCR positive (15 positive in direct FA and 4 positive in cytology, including one that was negative by PCR), whereas 37 dogs were negative in all methods. A good agreement was observed between the FA and PCR, with a κ-value of 0.833 (95% CI: 0.678-0.989). Meanwhile, there was poor agreement between cytology and PCR (κ-value of 0.164; 95% CI: -0.045 to 0.373) and a fair agreement between FA and cytology (κ-value of 0.231; 95% CI: -0.026 to 0.487). Our results indicated a poor performance of cytology for the detection of CDV antigen. In contrast, FA is a 100% specific and an adequately sensitive assay (sensitivity: 78.95%, negative likelihood ratio: 0.21, 95% CI: 0.09-0.50) for antemortem diagnosis of canine distemper.

  14. Development of a radioimmunoassay for a high molecular mass tubular antigen in urine - its application for early detection of tubular damage

    International Nuclear Information System (INIS)

    Sachse, H.J.; Falkenberg, F.W.; Scherberich, J.E.; Stefanescu, T.; Fassbinder, W.; Mondorf, A.W.; Schoeppe, W.

    1981-01-01

    In order to isolate urinary kidney antigens, the gammaglobulin fraction of an antiserum against human kidney cortex plasma membranes was coupled to Sepharose 4B. By immunospecific affinity chromatography an antigen fraction was obtained from the urine of a patient suffering from severe kidney disease. After gel filtration, the main fraction, eluted with the exclusion volume of a Sephadex G-200 column and enriched 16000-fold, was labelled with 131 I and used in a radioimmunoassay system. Soluble kidney antigens, presumably of proximal tubular origin, could be detected and quantified by the assay system in urine samples of patients with various diseases. The samples did not need to be treated, either concentrated or dialyzed, before application. The results of the experiments show a correlation between antigen excretion and kidney damage. Rejection episodes in patients with kidney transplants could be recognized early by enhanced antigen excretion. Potentially nephrotoxic drugs caused antigen excretion as well. In normal, healthy subjects output of the antigen was very low. The assay system might be of value for monitoring renal diseases. (Auth.)

  15. Horseradish peroxidase functionalized gold nanorods as a label for sensitive electrochemical detection of alpha-fetoprotein antigen.

    Science.gov (United States)

    Guo, Jinjin; Han, Xiaowei; Wang, Junchun; Zhao, Junqing; Guo, Zilin; Zhang, Yuzhong

    2015-12-15

    In this study, a novel tracer, horseradish peroxidase (HRP) functionalized gold nanorods (Au NRs) nanocomposites (HRP-Au NRs), was designed to label the signal antibodies for sensitive electrochemical measurement of alpha-fetoprotein (AFP). The preparation of HRP-Au NRs nanocomposites and the labeling of secondary antibody (Ab2) were performed by one-pot assembly of HRP and Ab2 on the surface of Au NRs. The immunosensor was fabricated by assembling carbon nanotubes (CNTs), Au NRs, and capture antibodies (Ab1) on the glassy carbon electrode. In the presence of AFP antigen, the labels were captured on the surface of the Au NRs/CNTs via specific recognition of antigen-antibody, resulting in the signal intensity being clearly increased. Differential pulse voltammetry (DPV) was employed to record the response signal of the immunosensor in phosphate-buffered saline (PBS) containing hydrogen peroxide (H2O2) and 3,3',5,5'-tetramethylbenzidine (TMB). Under optimal conditions, the signal intensity was linearly related to the concentration of AFP in the range of 0.1-100 ng ml(-1), and the limit of detection was 30 pg ml(-1) (at signal/noise [S/N] = 3). Furthermore, the immunoassay method was evaluated using human serum samples, and the recovery obtained was within 99.0 and 102.7%, indicating that the immunosensor has potential clinical applications. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Detection of prostate-specific antigen with biomolecule-gated AlGaN/GaN high electron mobility transistors

    Science.gov (United States)

    Li, Jia-dong; Cheng, Jun-jie; Miao, Bin; Wei, Xiao-wei; Xie, Jie; Zhang, Jin-cheng; Zhang, Zhi-qiang; Wu, Dong-min

    2014-07-01

    In order to improve the sensitivity of AlGaN/GaN high electron mobility transistor (HEMT) biosensors, a simple biomolecule-gated AlGaN/GaN HEMT structure was designed and successfully fabricated for prostate specific antigen (PSA) detection. UV/ozone was used to oxidize the GaN surface and then a 3-aminopropyl trimethoxysilane (APTES) self-assembled monolayer was bound to the sensing region. This monolayer serves as a binding layer for attachment of the prostate specific antibody (anti-PSA). The biomolecule-gated AlGaN/GaN HEMT sensor shows a rapid and sensitive response when the target prostate-specific antigen in buffer solution was added to the antibody-immobilized sensing area. The current change showed a logarithm relationship against the PSA concentration from 0.1 pg/ml to 0.993 ng/ml. The sensitivity of 0.215% is determined for 0.1 pg/ml PSA solution. The above experimental result of the biomolecule-gated AlGaN/GaN HEMT biosensor suggested that this biosensor might be a useful tool for prostate cancer screening.

  17. Detection of prostate-specific antigen with biomolecule-gated AlGaN/GaN high electron mobility transistors

    International Nuclear Information System (INIS)

    Li, Jia-dong; Miao, Bin; Wei, Xiao-wei; Xie, Jie; Wu, Dong-min; Cheng, Jun-jie; Zhang, Jin-cheng; Zhang, Zhi-qiang

    2014-01-01

    In order to improve the sensitivity of AlGaN/GaN high electron mobility transistor (HEMT) biosensors, a simple biomolecule-gated AlGaN/GaN HEMT structure was designed and successfully fabricated for prostate specific antigen (PSA) detection. UV/ozone was used to oxidize the GaN surface and then a 3-aminopropyl trimethoxysilane (APTES) self-assembled monolayer was bound to the sensing region. This monolayer serves as a binding layer for attachment of the prostate specific antibody (anti-PSA). The biomolecule-gated AlGaN/GaN HEMT sensor shows a rapid and sensitive response when the target prostate-specific antigen in buffer solution was added to the antibody-immobilized sensing area. The current change showed a logarithm relationship against the PSA concentration from 0.1 pg/ml to 0.993 ng/ml. The sensitivity of 0.215% is determined for 0.1 pg/ml PSA solution. The above experimental result of the biomolecule-gated AlGaN/GaN HEMT biosensor suggested that this biosensor might be a useful tool for prostate cancer screening. (paper)

  18. Cross-reactivity among antigens of different air-borne fungi detected by ELISA using five monoclonal antibodies against Penicillium notatum.

    Science.gov (United States)

    Shen, H D; Lin, W L; Chen, R J; Han, S H

    1990-10-01

    Cross-reactivity among antigens of 12 genera of air-borne fungi, 13 species of Penicillium, and 5 species of Aspergillus was studied by ELISA using five monoclonal antibodies (MoAbs) against Penicillium notatum. Epitopes recognized by all the five MoAbs were susceptible to treatment of mild periodate oxidation and may therefore be associated with carbohydrates. Furthermore, our results showed that there is cross-reactivity among antigens of Penicillium, Aspergillus, and Eurotium species. By using these MoAbs, cross reactivity was not detected between antigens of Penicillium notatum and antigens of Fusarium solani, Alternaria porri, Cladosporium cladosporoides, Curvularia species, Nigrospora species, Aureobasidium pullulans, Wallemia species, Rhizopus arrhizus, and Candida albicans. Cross-reactivity among antigens of 11 species of Penicillium and 5 species of Aspergillus could be detected by ELISA using one of the five MoAbs (MoAb P15). The fact that there may be cross-reactivity among antigens of closely related fungi species should be considered in the diagnosis and treatment of mold allergic diseases.

  19. Schistosome-induced cholangiocyte proliferation and osteopontin secretion correlate with fibrosis and portal hypertension in human and murine schistosomiasis mansoni.

    Science.gov (United States)

    Pereira, Thiago A; Syn, Wing-Kin; Machado, Mariana V; Vidigal, Paula V; Resende, Vivian; Voieta, Izabela; Xie, Guanhua; Otoni, Alba; Souza, Márcia M; Santos, Elisângela T; Chan, Isaac S; Trindade, Guilherme V M; Choi, Steve S; Witek, Rafal P; Pereira, Fausto E; Secor, William E; Andrade, Zilton A; Lambertucci, José Roberto; Diehl, Anna Mae

    2015-11-01

    Schistosomiasis is a major cause of portal hypertension worldwide. It associates with portal fibrosis that develops during chronic infection. The mechanisms by which the pathogen evokes these host responses remain unclear. We evaluated the hypothesis that schistosome eggs release factors that directly stimulate liver cells to produce osteopontin (OPN), a pro-fibrogenic protein that stimulates hepatic stellate cells to become myofibroblasts. We also investigated the utility of OPN as a biomarker of fibrosis and/or severity of portal hypertension. Cultured cholangiocytes, Kupffer cells and hepatic stellate cells were treated with soluble egg antigen (SEA); OPN production was quantified by quantitative reverse transcriptase polymerase chain reaction (qRTPCR) and ELISA; cell proliferation was assessed by BrdU (5-bromo-2'-deoxyuridine). Mice were infected with Schistosoma mansoni for 6 or 16 weeks to cause early or advanced fibrosis. Liver OPN was evaluated by qRTPCR and immunohistochemistry (IHC) and correlated with liver fibrosis and serum OPN. Livers from patients with schistosomiasis mansoni (early fibrosis n=15; advanced fibrosis n=72) or healthy adults (n=22) were immunostained for OPN and fibrosis markers. Results were correlated with plasma OPN levels and splenic vein pressures. SEA-induced cholangiocyte proliferation and OPN secretion (Pportal hypertension severity. © 2015 Authors; published by Portland Press Limited.

  20. Simultaneous Detection of α-Fetoprotein and Carcinoembryonic Antigen Based on Si Nanowire Field-Effect Transistors

    Directory of Open Access Journals (Sweden)

    Kuiyu Zhu

    2015-08-01

    Full Text Available Primary hepatic carcinoma (PHC is one of the most common malignancies worldwide, resulting in death within six to 20 months. The survival rate can be improved by effective treatments when diagnosed at an early stage. The α-fetoprotein (AFP and carcinoembryonic antigen (CEA have been identified as markers that are expressed at higher levels in PHC patients. In this study, we employed silicon nanowire field-effect transistors (SiNW-FETs with polydimethylsiloxane (PDMS microfluidic channels to simultaneously detect AFP and CEA in desalted human serum. Dual-channel PDMS was first utilized for the selective modification of AFP and CEA antibodies on SiNWs, while single-channel PDMS offers faster and more sensitive detection of AFP and CEA in serum. During the SiNW modification process, 0.1% BSA was utilized to minimize nonspecific protein binding from serum. The linear dynamic ranges for the AFP and CEA detection were measured to be 500 fg/mL to 50 ng/mL and 50 fg/mL to 10 ng/mL, respectively. Our work demonstrates the promising potential of fabricated SiNW-FETs as a direct detection kit for multiple tumor markers in serum; therefore, it provides a chance for early stage diagnose and, hence, more effective treatments for PHC patients.

  1. The diagnosis of malaria infection using a solid-phase radioimmunoassay for the detection of malaria antigens

    International Nuclear Information System (INIS)

    Mackey, L.; Perrin, L.; Leemans, E.; Lambert, P.H.

    1980-01-01

    A method was devised to show that malaria parasites can be detected serologically in infected blood with a high degree of sensitivity. Using a murine malaria model, parasites were demonstrated in a solid-phase radio-immunoassay which measured antibody-binding inhibition. Lysed red blood cells (r.b.c.) were incubated with labelled specific antibody and were then reacted in antigen-coated tubes. The degree of inhibition of antibody binding in the tubes correlated with the level of parasitaemia in the test blood. Using homologous antisera the test detected infection at a level of 1 parasite/million r.b.c.. The specificity of the method was shown by comparison of antibody-binding inhibition in normal and infected r.b.c. and in r.b.c. from non-infected mice with induced reticulocytosis. The sensitivity was shown in vitro in tests of serially diluted blood of high parasitaemia and in vivo for the detection of early infection. The presence of antibody in the test blood did not significantly affect the sensitivity of parasite detection. (author)

  2. Novel antigens used to detect cell-mediated immune responses over time in Mycobacterium avium subsp. paratuberculosis infected cattle

    DEFF Research Database (Denmark)

    Mikkelsen, Heidi; Aagaard, Claus; Nielsen, Søren Saxmose

    consisting of undefined antigens with possible cross reactions toward other environmental bacteria. The objective of the study was to optimize the IFN-γ test using different types of novel antigens for stimulation. Fourteen novel antigen candidates were selected for testing, including 4 peptides of the ESAT...

  3. Identification of threshold prostate specific antigen levels to optimize the detection of clinically significant prostate cancer by magnetic resonance imaging/ultrasound fusion guided biopsy.

    Science.gov (United States)

    Shakir, Nabeel A; George, Arvin K; Siddiqui, M Minhaj; Rothwax, Jason T; Rais-Bahrami, Soroush; Stamatakis, Lambros; Su, Daniel; Okoro, Chinonyerem; Raskolnikov, Dima; Walton-Diaz, Annerleim; Simon, Richard; Turkbey, Baris; Choyke, Peter L; Merino, Maria J; Wood, Bradford J; Pinto, Peter A

    2014-12-01

    Prostate specific antigen sensitivity increases with lower threshold values but with a corresponding decrease in specificity. Magnetic resonance imaging/ultrasound targeted biopsy detects prostate cancer more efficiently and of higher grade than standard 12-core transrectal ultrasound biopsy but the optimal population for its use is not well defined. We evaluated the performance of magnetic resonance imaging/ultrasound targeted biopsy vs 12-core biopsy across a prostate specific antigen continuum. We reviewed the records of all patients enrolled in a prospective trial who underwent 12-core transrectal ultrasound and magnetic resonance imaging/ultrasound targeted biopsies from August 2007 through February 2014. Patients were stratified by each of 4 prostate specific antigen cutoffs. The greatest Gleason score using either biopsy method was compared in and across groups as well as across the population prostate specific antigen range. Clinically significant prostate cancer was defined as Gleason 7 (4 + 3) or greater. Univariate and multivariate analyses were performed. A total of 1,003 targeted and 12-core transrectal ultrasound biopsies were performed, of which 564 diagnosed prostate cancer for a 56.2% detection rate. Targeted biopsy led to significantly more upgrading to clinically significant disease compared to 12-core biopsy. This trend increased more with increasing prostate specific antigen, specifically in patients with prostate specific antigen 4 to 10 and greater than 10 ng/ml. Prostate specific antigen 5.2 ng/ml or greater captured 90% of upgrading by targeted biopsy, corresponding to 64% of patients who underwent multiparametric magnetic resonance imaging and subsequent fusion biopsy. Conversely a greater proportion of clinically insignificant disease was detected by 12-core vs targeted biopsy overall. These differences persisted when controlling for potential confounders on multivariate analysis. Prostate cancer upgrading with targeted biopsy increases

  4. Detection of human leukocyte antigen compatibility and antibodies in liver transplantation in China

    Institute of Scientific and Technical Information of China (English)

    Xue-Qin Meng; Xuan Zhang; Jun Fan; Lin Zhou; Bing Hao; Xiao-Ming Chen; Wei-Hang Ma; Shu-Sen Zheng

    2009-01-01

    BACKGROUND: The exact roles of human leukocyte antigen (HLA) compatibility, HLA antibodies and underlying diseases in acute rejection of liver transplants are not clear. Moreover, cytomegalovirus (CMV) infection, one of the most common infections after transplantation, is related to HLA genotype and the incidence of acute rejection. METHODS: Since there are controversial reports, we analyzed the impact of HLA matching, HLA antibodies and underlying diseases in 38 liver transplant recipients in China, and assessed the association of CMV infection and HLA compatibility. RESULTS: The frequency of no HLA compatibility was high in patients without antigenemia (P=0.019). All 17 patients with HLA-A matching developed antigenemia (P0.05). In patients with acute rejection, no differences were found in the incidence of acute rejection in transplants for hepatitis B, tumors, or combined hepatitis B and tumors (P>0.05).CONCLUSIONS: There are fewer acute rejections in transplants with more HLA compatibilities. Speciifc investigations of underlying diseases and HLA typing may be necessary in liver transplantation. The mechanisms of CMV infection and HLA matching should be further studied. HLA before transplantation should be examined for the prevention of acute rejection and CMV infection.

  5. Utility of PCR, Culture, and Antigen Detection Methods for Diagnosis of Legionellosis.

    Science.gov (United States)

    Chen, Derrick J; Procop, Gary W; Vogel, Sherilynn; Yen-Lieberman, Belinda; Richter, Sandra S

    2015-11-01

    The goal of this retrospective study was to evaluate the performance of different diagnostic tests for Legionnaires' disease in a clinical setting where Legionella pneumophila PCR had been introduced. Electronic medical records at the Cleveland Clinic were searched for Legionella urinary antigen (UAG), culture, and PCR tests ordered from March 2010 through December 2013. For cases where two or more test methods were performed and at least one was positive, the medical record was reviewed for relevant clinical and epidemiologic factors. Excluding repeat testing on a given patient, 19,912 tests were ordered (12,569 UAG, 3,747 cultures, and 3,596 PCR) with 378 positive results. The positivity rate for each method was 0.4% for culture, 0.8% for PCR, and 2.7% for UAG. For 37 patients, at least two test methods were performed with at least one positive result: 10 (27%) cases were positive by all three methods, 16 (43%) were positive by two methods, and 11 (30%) were positive by one method only. For the 32 patients with medical records available, clinical presentation was consistent with proven or probable Legionella infection in 84% of the cases. For those cases, the sensitivities of culture, PCR, and UAG were 50%, 92%, and 96%, respectively. The specificities were 100% for culture and 99.9% for PCR and UAG. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  6. Evaluation of twenty rapid antigen tests for the detection of human influenza A H5N1, H3N2, H1N1, and B viruses.

    Science.gov (United States)

    Taylor, Janette; McPhie, Kenneth; Druce, Julian; Birch, Chris; Dwyer, Dominic E

    2009-11-01

    Twenty rapid antigen assays were compared for their ability to detect influenza using dilutions of virus culture supernatants from human isolates of influenza A H5N1 (clade 1 and 2 strains), H3N2 and H1N1 viruses, and influenza B. There was variation amongst the rapid antigen assays in their ability to detect different influenza viruses. Six of the 12 assays labeled as distinguishing between influenza A and B had comparable analytical sensitivities for detecting both influenza A H5N1 strains, although their ability to detect influenza A H3N2 and H1N1 strains varied. The two assays claiming H5 specificity did not detect either influenza A H5N1 strains, and the two avian influenza-specific assays detected influenza A H5N1, but missed some influenza A H3N2 virus supernatants. Clinical trials of rapid antigen tests for influenza A H5N1 are limited. For use in a pandemic where novel influenza strains are circulating (such as the current novel influenza A H1N1 09 virus), rapid antigen tests should ideally have comparable sensitivity and specificity for the new strains as for co-circulating seasonal influenza strains.

  7. Rapid antigen detection test for respiratory syncytial virus diagnosis as a diagnostic tool

    Directory of Open Access Journals (Sweden)

    Flávio da Silva Mesquita

    2017-05-01

    Conclusions: This study demonstrated that the QuickVue® RSV Test Kit can be effective in early detection of Respiratory syncytial virus in nasopharyngeal aspirate and is reliable for use as a diagnostic tool in pediatrics.

  8. Comparative study of methods of detection of hepatitis ′B′ surface antigen (HBsAg.

    Directory of Open Access Journals (Sweden)

    Parab V

    1989-04-01

    Full Text Available The serum samples were collected from 52 patients of acute viral hepatitis and 235 hospital staff from Kasturba Hospital for Infectious Diseases. HBsAg was detected in their sera by counter-immuno-electrophoresis (CIEP, reverse passive hemogglutination (RPHA and by micro-enzyme-linked-immunosorbent assay (ELISA technique. Among the patients, HBsAg was detected in 12 cases (23% by CIEP, in 18 cases (34% by RPHA and in 23 patients (45% by ELISA. In the hospital staff, HBsAg was detected in 4 samples (1.7% by CIEP, in 8 samples (3.5% by RPHA and in 32 samples (13.5% by ELISA. Thus ELISA was found to be the most sensitive technique in detecting HBsAg.

  9. Molecular phylogenetics of the elephant schistosome Bivitellobilharzia loxodontae (Trematoda: Schistosomatidae) from the Central African Republic

    Czech Academy of Sciences Publication Activity Database

    Brant, S. V.; Pomajbíková, K.; Modrý, David; Petrželková, Klára Judita; Todd, A.; Loker, E. S.

    2013-01-01

    Roč. 87, č. 01 (2013), s. 102-107 ISSN 0022-149X R&D Projects: GA ČR GA206/09/0927 Institutional research plan: CEZ:AV0Z60220518 Institutional support: RVO:68081766 ; RVO:60077344 Keywords : schistosomes * elephant Subject RIV: EG - Zoology Impact factor: 1.303, year: 2013

  10. A new technique to detect antibody-antigen reaction (biological interactions) on a localized surface plasmon resonance (LSPR) based nano ripple gold chip

    Energy Technology Data Exchange (ETDEWEB)

    Saleem, Iram, E-mail: iiram.qau@gmail.com [Department of Physics and Texas Center for Superconductivity, University of Houston, Houston, TX 77204 (United States); Widger, William, E-mail: widger@uh.edu [Department of Biology and Biochemistry and Texas Center for Superconductivity, University of Houston, Houston, TX 77204 (United States); Chu, Wei-Kan, E-mail: wkchu@uh.edu [Department of Physics and Texas Center for Superconductivity, University of Houston, Houston, TX 77204 (United States)

    2017-07-31

    Highlights: • The nano ripple LSPR chip has monolayer molecule-coating sensitivity and specific selectivity. • Gold nano-ripple sensing chip is a low cost, and a label-free method for detecting the antibody-antigen reaction. • The plasmonic resonance shift depends upon the concentration of the biomolecules attached on the surface of the nano ripple pattern. - Abstract: We demonstrate that the gold nano-ripple localized surface plasmon resonance (LSPR) chip is a low cost and a label-free method for detecting the presence of an antigen. A uniform stable layer of an antibody was coated on the surface of a nano-ripple gold pattern chip followed by the addition of different concentrations of the antigen. A red shift was observed in the LSPR spectral peak caused by the change in the local refractive index in the vicinity of the nanostructure. The LSPR chip was fabricated using oblique gas cluster ion beam (GCIB) irradiation. The plasmon-resonance intensity of the scattered light was measured by a simple optical spectroscope. The gold nano ripple chip shows monolayer scale sensitivity and high selectivity. The LSPR substrate was used to detect antibody-antigen reaction of rabbit X-DENTT antibody and DENTT blocking peptide (antigen).

  11. Antigens of worms and eggs showed a differentiated detection of specific IgG according to the time of Schistosoma mansoni infection in mice

    Directory of Open Access Journals (Sweden)

    Rafaella Fortini Queiroz Grenfell

    2012-08-01

    Full Text Available INTRODUCTION: The correlation between the immunological assay and the antibody titer can offer a tool for the experimental analysis of different phases of the disease. METHODS: Two simple immunological assays for Schistosoma mansoni in mice sera samples based on specific IgG detection for worms soluble antigens and eggs soluble antigens were standardized and evaluated in our laboratory. Fifty mice were used in negative and positive groups and the results obtained by enzyme-linked immunosorbent assays (ELISA assays were compared with the number of worms counted and the IgG titers at different times of infection. RESULTS: Data showed that ELISA using adult worm antigens (ELISA-SWAP presented a satisfactory correlation between the absorbance value of IgG titers and the individual number of worms counted after perfusion technique (R²=0.62. In addition, ELISA-SWAP differentially detected positive samples with 30 and 60 days post infection (p=0.011 and 0.003, respectively, whereas ELISA using egg antigens (ELISA-SEA detected samples after 140 days (p=0.03. CONCLUSIONS: These data show that the use of different antigens in immunological methods can be used as potential tools for the analysis of the chronological evolution of S. mansoni infection in murine schistosomiasis. Correlations with human schistosomiasis are discussed.

  12. An ultrasensitive electrochemical immunosensor for the detection of prostate-specific antigen based on conductivity nanocomposite with halloysite nanotubes.

    Science.gov (United States)

    Li, Yueyuan; Khan, Malik Saddam; Tian, Lihui; Liu, Li; Hu, Lihua; Fan, Dawei; Cao, Wei; Wei, Qin

    2017-05-01

    A sensitive label-free amperometric electrochemical immunosensor for detection of prostate-specific antigen (PSA) was proposed in this work. The nanocomposite of halloysite nanotubes with polypyrrole shell and palladium nanoparticles (HNTs@PPy-Pd) was used as a novel signal label. The HNTs with adequate hydroxyl groups are economically available raw materials. PPy, as an electrically conducting polymer material, can be absorbed to the surface of HNTs by in situ oxidative polymerization of the pyrrole monomer and form a shell on the HNTs. The shell of PPy could not only improve the conductivity of the nanocomposite but also absorb large amounts of Pd nanoparticles (NPs). The Pd NPs with high electrocatalytic activity toward the reduction of H 2 O 2 and the HNTs@PPy-Pd nanocomposite as the analytical signal label could improve the sensitivity of the immunosensor. Under optimal conditions, the immunosensor showed a low detection limit (0.03 pg/mL) and a wide linear range (0.0001 to 25 ng/mL) of PSA. Moreover, its merits such as good selectivity, acceptable reproducibility, and stability indicate that the fabricated immunosensor has a promising application potential in clinical diagnosis. Graphical Abstract A new label-free amperometric electrochemical immunosensor based on HNTs@PPy-Pd nanocomposite for quantitative detection of PSA.

  13. Polyhydroquinone-graphene composite as new redox species for sensitive electrochemical detection of cytokeratins antigen 21-1

    Science.gov (United States)

    Wang, Huiqiang; Rong, Qinfeng; Ma, Zhanfang

    2016-07-01

    Polyhydroquinone-graphene composite as a new redox species was synthesized simply by a microwave-assisted one-pot method through oxidative polymerization of hydroquinone by graphene oxide, which exhibited excellent electrochemical redox activity at 0.124 V and can remarkably promote electron transfer. The as-prepared composite was used as immunosensing substrate in a label-free electrochemical immunosensor for the detection of cytokeratins antigen 21-1, a kind of biomarker of lung cancer. The proposed immunosensor showed wide liner range from 10 pg mL-1 to 200 ng mL-1 with a detection limit 2.3 pg mL-1, and displayed a good stability and selectivity. In addition, this method has been used for the analysis of human serum sample, and the detection results showed good consistence with those of ELISA. The present substrate can be easily extended to other polymer-based nanocomposites.

  14. Evaluation of monoclonal antibody-based sandwich direct ELISA (MSD-ELISA for antigen detection of foot-and-mouth disease virus using clinical samples.

    Directory of Open Access Journals (Sweden)

    Kazuki Morioka

    Full Text Available A monoclonal antibody-based sandwich direct ELISA (MSD-ELISA method was previously developed for foot-and-mouth disease (FMD viral antigen detection. Here we evaluated the sensitivity and specificity of two FMD viral antigen detection MSD-ELISAs and compared them with conventional indirect sandwich (IS-ELISA. The MSD-ELISAs were able to detect the antigen in saliva samples of experimentally-infected pigs for a longer term compared to the IS-ELISA. We also used 178 RT-PCR-positive field samples from cattle and pigs affected by the 2010 type-O FMD outbreak in Japan, and we found that the sensitivities of both MSD-ELISAs were about 7 times higher than that of the IS-ELISA against each sample (P<0.01. In terms of the FMD-positive farm detection rate, the sensitivities of the MSD-ELISAs were about 6 times higher than that of the IS-ELISA against each farm (P<0.01. Although it is necessary to conduct further validation study using the other virus strains, MSD-ELISAs could be appropriate as a method to replace IS-ELISA for FMD antigen detection.

  15. Evaluation of monoclonal antibody-based sandwich direct ELISA (MSD-ELISA) for antigen detection of foot-and-mouth disease virus using clinical samples.

    Science.gov (United States)

    Morioka, Kazuki; Fukai, Katsuhiko; Sakamoto, Kenichi; Yoshida, Kazuo; Kanno, Toru

    2014-01-01

    A monoclonal antibody-based sandwich direct ELISA (MSD-ELISA) method was previously developed for foot-and-mouth disease (FMD) viral antigen detection. Here we evaluated the sensitivity and specificity of two FMD viral antigen detection MSD-ELISAs and compared them with conventional indirect sandwich (IS)-ELISA. The MSD-ELISAs were able to detect the antigen in saliva samples of experimentally-infected pigs for a longer term compared to the IS-ELISA. We also used 178 RT-PCR-positive field samples from cattle and pigs affected by the 2010 type-O FMD outbreak in Japan, and we found that the sensitivities of both MSD-ELISAs were about 7 times higher than that of the IS-ELISA against each sample (P<0.01). In terms of the FMD-positive farm detection rate, the sensitivities of the MSD-ELISAs were about 6 times higher than that of the IS-ELISA against each farm (P<0.01). Although it is necessary to conduct further validation study using the other virus strains, MSD-ELISAs could be appropriate as a method to replace IS-ELISA for FMD antigen detection.

  16. Fluorescent QDs-polystyrene composite nanospheres for highly efficient and rapid protein antigen detection

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Changhua; Mao, Mao [Henan University, Key Laboratory for Special Functional Materials of the Ministry of Education (China); Yuan, Hang [Tsinghua University, Life Science Division, Graduate School at Shenzhen (China); Shen, Huaibin [Henan University, Key Laboratory for Special Functional Materials of the Ministry of Education (China); Wu, Feng; Ma, Lan, E-mail: malan@sz.tsinghua.edu.cn [Tsinghua University, Life Science Division, Graduate School at Shenzhen (China); Li, Lin Song, E-mail: lsli@henu.edu.cn [Henan University, Key Laboratory for Special Functional Materials of the Ministry of Education (China)

    2013-09-15

    In this paper, high-quality carboxyl-functionalized fluorescent (red, green, and blue emitting) nanospheres (46-103 nm) consisting of hydrophobic quantum dots (QDs) and polystyrene were prepared by a miniemulsion polymerization approach. This miniemulsion polymerization approach induced a homogeneous distribution and high aqueous-phase transport efficiency of fluorescent QDs in composite nanospheres, which proved the success of our encoding QDs strategy. The obtained fluorescent nanospheres exhibited high stability in aqueous solution under a wide range of pH, different salt concentrations, PBS buffer, and thermal treatment at 80 Degree-Sign C. Based on the red emitting composite nanosphere, we performed fluorescent lateral flow immunoassay (LFIA) strips for high-sensitivity and rapid alpha-fetal protein detection. The detection limit reached 0.1 ng/mL, which was 200 times higher than commercial colloidal gold-labeled LFIA strips, and it reached similar detection level in enzyme-linked immunosorbent assay kit.

  17. Evaluation of detection methodology for carcinoembryonic antigen and application of CEA in diagnosis of gastric cancer

    International Nuclear Information System (INIS)

    Wang Enlan; Li Tao

    2005-01-01

    To compare the specificity and sensitivity of different methods in detection of CEA, and to investigate the application of CEA detection in diagnosis of gastric cancer, CEA in serum of 36 patients with gastric cancer and 20 negtive reference serum was detected by ELISA, TR- FIA, RIA and CLIA. The results showed that the specificity of these 4 methods was all 100% and the sensitivity of ELISA was the lowest (19.4%) while CLIA was the highest (44.4%). Therefore, the sensitivity of ELISA should be raised and CEA, besides used as an observation index for curative effects in a part of gastric cancer patients, can not be used in diagnosis of gastric cancer. (authors)

  18. A novel colloidal gold labeled antigen for the detection of Deoxynivalenol using an immunochromatographic assay method

    Science.gov (United States)

    Jin, Yu; Liu, Renrong; Zhu, Lixin; Chen, Zhenzhen

    2017-11-01

    In this paper, an immunochromatographic assay card was developed for the detection of DON in feed and cereals using a novel colloidal gold labeling method. For the colloidal gold immunochromatographic rapid detection (GICD) card, a monoclonal antibody DON-mAb and a goat anti-chicken IgY were drawn on NC membrane as the test line (T line) and the control line (C line) respectively. A gold labeled DON-CBSA conjugate and a gold labeled chicken IgY were sprayed onto the conjugate pad. The GICD card has cut-off levels of 50ng/mL for DON, which is invulnerable to matrix interference, and applicable to a wide range of samples. The GICD detecting results of feed and grain samples were compared with the results of ELISA testing, which showed good consistency.

  19. Microfluidic-integrated patterned ITO immunosensor for rapid detection of prostate-specific membrane antigen biomarker in prostate cancer.

    Science.gov (United States)

    Seenivasan, Rajesh; Singh, Chandra K; Warrick, Jay W; Ahmad, Nihal; Gunasekaran, Sundaram

    2017-09-15

    An optically transparent patterned indium tin oxide (ITO) three-electrode sensor integrated with a microfluidic channel was designed for label-free immunosensing of prostate-specific membrane antigen (PSMA), a prostate cancer (PCa) biomarker, expressed on prostate tissue and circulating tumor cells but also found in serum. The sensor relies on cysteamine capped gold nanoparticles (N-AuNPs) covalently linked with anti-PSMA antibody (Ab) for target specificity. A polydimethylsiloxane (PDMS) microfluidic channel is used to efficiently and reproducibly introduce sample containing soluble proteins/cells to the sensor. The PSMA is detected and quantified by measuring the change in differential pulse voltammetry signal of a redox probe ([Fe(CN) 6 ] 3- /[Fe(CN) 6 ] 4- ) that is altered upon binding of PSMA with PSMA-Ab immobilized on N-AuNPs/ITO. Detection of PSMA expressing cells and soluble PSMA was tested. The limit of detection (LOD) of the sensor for PSMA-based PCa cells is 6/40µL (i.e., 150 cells/mL) (n=3) with a linear range of 15-400 cells/40µL (i.e., 375-10,000 cells/mL), and for the soluble PSMA is 0.499ng/40µL (i.e., 12.5ng/mL) (n=3) with the linear range of 0.75-250ng/40µL (i.e., 19-6250ng/mL), both with an incubation time of 10min. The results indicate that the sensor has a suitable sensitivity and dynamic range for routine detection of PCa circulating tumor cells and can be adapted to detect other biomarkers/cancer cells. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Detection of a nuclear, EBNA-type antigen in apparently EBNA-negative Herpesvirus papio (HVP)-transformed lymphoid lines by the acid-fixed nuclear binding technique.

    Science.gov (United States)

    Ohno, S; Luka, J; Falk, L; Klein, G

    1977-12-15

    In agreement with the findings of previous authors, we could not detect a virally determined nuclear antigen in Herpesvirus papio (HVP)-transformed baboon lymphoid lines by anticomplementary staining in situ, as for EBNA. However, by means of our recently developed acid-fixed nuclear binding technique an EBNA-like antigen could be readily demonstrated, after extraction from both producer and non-producer lines. We propose to designate the antigen as HUPNA. It can be detected by a human anti-EBNA antibody, suggesting cross-reactivity, if not identity, between EBNA and HUPNA. HVP-DNA carrying non-producer lines, negative for in situ ACIF stainability but capable of yielding HUPNA by the nuclear binding technique, can be superinfected with EBV, with brilliant EBNA expression as the result, suggesting that the defective in situ staining is a property associated with the baboon HVP, rather than the baboon lymphoid cell per se.

  1. Rapidly boosted Plasma IL-5 induced by treatment of human Schistosomiasis haematobium is dependent on antigen dose, IgE and eosinophils

    DEFF Research Database (Denmark)

    Wilson, Shona; Jones, Frances M.; Fofana, Hassan K. M.

    2013-01-01

    IgE specific to worm antigen (SWA) and pre-treatment eosinophil number, are associated with human immunity to re-infection with schistosomes after chemotherapeutic treatment. Treatment significantly elevates circulating IL-5 24-hr post-treatment of Schistosoma mansoni. Here we investigate...

  2. Detection of antigen in sera of patients with invasive aspergillosis : Intra- and interlaboratory reproducibility

    NARCIS (Netherlands)

    Verweij, PE; Erjavec, Z; Sluiters, W; Goessens, W; Rozenberg-Arska, M; Debets-Ossenkopp, YJ; Guiot, HFL; Meis, JFGM

    The intra-and interlaboratory reproducibilities of a commercial sandwich enzyme-linked immunosorbent assay (ELISA) for the detection of Aspergillus galactomannan in serum (Platelia Aspergillus; Sanofi Diagnostics Pasteur, Marnes-La-Coquette, France) were evaluated in six laboratories of university

  3. Genetic diversity of merozoite surface antigens in Babesia bovis detected from Sri Lankan cattle.

    Science.gov (United States)

    Sivakumar, Thillaiampalam; Okubo, Kazuhiro; Igarashi, Ikuo; de Silva, Weligodage Kumarawansa; Kothalawala, Hemal; Silva, Seekkuge Susil Priyantha; Vimalakumar, Singarayar Caniciyas; Meewewa, Asela Sanjeewa; Yokoyama, Naoaki

    2013-10-01

    Babesia bovis, the causative agent of severe bovine babesiosis, is endemic in Sri Lanka. The live attenuated vaccine (K-strain), which was introduced in the early 1990s, has been used to immunize cattle populations in endemic areas of the country. The present study was undertaken to determine the genetic diversity of merozoite surface antigens (MSAs) in B. bovis isolates from Sri Lankan cattle, and to compare the gene sequences obtained from such isolates against those of the K-strain. Forty-four bovine blood samples isolated from different geographical regions of Sri Lanka and judged to be B. bovis-positive by PCR screening were used to amplify MSAs (MSA-1, MSA-2c, MSA-2a1, MSA-2a2, and MSA-2b), AMA-1, and 12D3 genes from parasite DNA. Although the AMA-1 and 12D3 gene sequences were highly conserved among the Sri Lankan isolates, the MSA gene sequences from the same isolates were highly diverse. Sri Lankan MSA-1, MSA-2c, MSA-2a1, MSA-2a2, and MSA-2b sequences clustered within 5, 2, 4, 1, and 9 different clades in the gene phylograms, respectively, while the minimum similarity values among the deduced amino acid sequences of these genes were 36.8%, 68.7%, 80.3%, 100%, and 68.3%, respectively. In the phylograms, none of the Sri Lankan sequences fell within clades containing the respective K-strain sequences. Additionally, the similarity values for MSA-1 and MSA-2c were 40-61.8% and 90.9-93.2% between the Sri Lankan isolates and the K-strain, respectively, while the K-strain MSA-2a/b sequence shared 64.5-69.8%, 69.3%, and 70.5-80.3% similarities with the Sri Lankan MSA-2a1, MSA-2a2, and MSA-2b sequences, respectively. The present study has shown that genetic diversity among MSAs of Sri Lankan B. bovis isolates is very high, and that the sequences of field isolates diverged genetically from the K-strain. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Malaria prevalence defined by microscopy, antigen detection, DNA amplification and total nucleic acid amplification in a malaria-endemic region during the peak malaria transmission season.

    Science.gov (United States)

    Waitumbi, John N; Gerlach, Jay; Afonina, Irina; Anyona, Samuel B; Koros, Joseph N; Siangla, Joram; Ankoudinova, Irina; Singhal, Mitra; Watts, Kate; Polhemus, Mark E; Vermeulen, Nicolaas M; Mahoney, Walt; Steele, Matt; Domingo, Gonzalo J

    2011-07-01

    To determine the malaria prevalence by microscopy, antigen detection and nucleic acid detection in a defined subpopulation in a Plasmodium falciparum-endemic region during the peak transmission season. Blood specimens were collected in a cross-sectional study involving children aged 5-10 years (n = 195) presenting with acute fever to two clinics in Western Kenya. All specimens underwent microscopy, HRP2 and aldolase antigen detection by enzyme immunoassay (EIA), parasite-specific DNA and total nucleic acid (RNA and DNA) by real-time PCR (qPCR) and reverse-transcriptase PCR (qRT-PCR). Microscopy detected 65/195 cases of malaria infection [95% confidence interval (CI) 52-78]. HRP2 and aldolase EIA had similar sensitivity levels detecting antigen in 65/195 (95% CI, 52-78) and 57/195 (95% CI, 45-70) cases. Discordants in antigen detection vs. microscopy occurred at Detection of total nucleic acid allowed a 3 log lower limit of detection than just DNA detection by real-time PCR in vitro. In clinical specimens, 114/195 (95% CI, 100-127) were qPCR positive (DNA), and 187/195 (95% CI, 179-191) were qRT-PCR positive (DNA plus RNA). The prevalence of submicroscopic malaria infection was significantly higher when detecting total nucleic acid than just DNA in this outpatient population during the high transmission season. Defining standards for submicroscopic infection will be important for control programmes, diagnostics development efforts and molecular epidemiology studies. © 2011 Blackwell Publishing Ltd.

  5. Analytical validation of a reference laboratory ELISA for the detection of feline leukemia virus p27 antigen.

    Science.gov (United States)

    Buch, Jesse S; Clark, Genevieve H; Cahill, Roberta; Thatcher, Brendon; Smith, Peter; Chandrashekar, Ramaswamy; Leutenegger, Christian M; O'Connor, Thomas P; Beall, Melissa J

    2017-09-01

    Feline leukemia virus (FeLV) is an oncogenic retrovirus of cats. Immunoassays for the p27 core protein of FeLV aid in the detection of FeLV infections. Commercial microtiter-plate ELISAs have rapid protocols and visual result interpretation, limiting their usefulness in high-throughput situations. The purpose of our study was to validate the PetChek FeLV 15 ELISA, which is designed for the reference laboratory, and incorporates sequential, orthogonal screening and confirmatory protocols. A cutoff for the screening assay was established with 100% accuracy using 309 feline samples (244 negative, 65 positive) defined by the combined results of FeLV PCR and an independent reference p27 antigen ELISA. Precision of the screening assay was measured using a panel of 3 samples (negative, low-positive, and high-positive). The intra-assay coefficient of variation (CV) was 3.9-7.9%; the inter-assay CV was 6.0-8.6%. For the confirmatory assay, the intra-assay CV was 3.0-4.7%, and the inter-assay CV was 7.4-9.7%. The analytical sensitivity for p27 antigen was 3.7 ng/mL for inactivated whole FeLV and 1.2 ng/mL for purified recombinant FeLV p27. Analytical specificity was demonstrated based on the absence of cross-reactivity to related retroviruses. No interference was observed for samples containing added bilirubin, hemoglobin, or lipids. Based on these results, the new high-throughput design of the PetChek FeLV 15 ELISA makes it suitable for use in reference laboratory settings and maintains overall analytical performance.

  6. The clinical significance of detection of serum Pre-S1 antigen

    International Nuclear Information System (INIS)

    Jiang Xuehua; Huang Zhuqing; Han Yi; Gong Shoujun

    2003-01-01

    To study the clinical significance of detection of serum Pre-S 1 Ag, the serum Pre-S 1 Ag, HBV-marks and HBV-DNA were detected in 338 patients with hepatitis B. The positive rate and the relationship between them were analyzed and compared. In 338 patients, the positive rate of serum Pre-S 1 Ag, HBeAg, HBV-DNA was 63.02%, 48.52%, 68.05% respectively, and the co-positive rate of Pre-S 1 Ag with HBV-DNA, HBeAg was 78.56%, 81.17% respectively. There was a significant correlation between Pre-S 1 Ag, HBeAg and HBV-DNA (P 1 Ag could well reflect the reproductive status of hepatitis B virus, and so it could be used as the clinical marker of the reproductive status of hepatitis B virus

  7. Electrochemical Detecting Lung Cancer-Associated Antigen Based on Graphene-Gold Nanocomposite

    Directory of Open Access Journals (Sweden)

    Zheng Wei

    2017-03-01

    Full Text Available Using a Au nanoparticle/reduced graphene oxide composite (AuNP-RGO, a signal-enhanced electrochemical immunosensor without label was created to detect neuron-specific enolase (NSE. Furthermore, an environmentally-friendly method was developed to prepare AuNP-RGO by employing chitosan (CS, which served as reducing and stabilizing agent. We showed that the sensitivity of the immunosensor designed in this report was remarkably enhanced because of the numerous active sites in the sensor provided by the AuNP-RGO nanostructure. For the quantification of NSE, the immunosensor exhibited a positive linear relationship with the concentration in the range of 0.1 to 2000 ng/mL, where the limit of the detection was 0.05 ng/mL.

  8. Detection of Clonorchis sinensis circulating antigen in sera from Chinese patients by immunomagnetic bead ELISA based on IgY.

    Directory of Open Access Journals (Sweden)

    Ge Nie

    Full Text Available BACKGROUND: Clonorchiasis, caused by Clonorchis sinensis, is widely distributed in Southeast Asia including China. Clonorchiasis is included in control programs of neglected tropical diseases by World Health Organization (WHO because it is one of the major health problems in most endemic areas. Diagnosis of clonorchiasis plays a key role in the control programs. However, so far, there is no satisfactory method for clonorchiasis because of low sensitivity, poor practicality and high false positivity of available diagnostic tools. METHODOLOGY/PRINCIPAL FINDINGS: We developed an immunomagnetic bead enzyme-linked immunosorbent assay (ELISA based on IgY (egg yolk immunoglobulin against cysteine proteinase of C. sinensis for detection of circulating antigen in serum samples of patients infected with C. sinensis. The polyclonal IgY, coated with magnetic beads, was used as a capture antibody and a monoclonal IgG labeled with horseradish peroxidase as a detection antibody in the IgY-based immunomagnetic bead ELISA system (IgY-IMB-ELISA. The results showed that the sensitivity of IgY-IMB-ELISA was 93.3% (14 of 15 in cases of heavy infection (5000 to 9999 eggs per gram feces, i.e, EPG 5000-9999, 86.7% (13 of 15 in cases of moderate infection (EPG 1000-4999 and 75.0% (9 of 12 in cases of light infection (EPG <1000 of clonorchiasis. Together 36 of total 42 (85.7% serum samples of human clonorchiasis gave a positive reaction. There was a significant correlation between ELISA optical density and egg counts (EPG with a correlation coefficient of 0.83 in total 42 patients. There were no positive results in patients with trichinosis (n = 10 or cysticercosis (n = 10. Cross-reactivity was 6.7% (2 of 30 with schistosomiasis japonica and 10.0% (3 of 30 with paragonimiasis, respectively. No positive reaction was found in 20 healthy persons. CONCLUSIONS: Our findings suggest that IgY-IMB-ELISA appears to be a sensitive and specific assay for detection of circulating

  9. Detection of Clonorchis sinensis circulating antigen in sera from Chinese patients by immunomagnetic bead ELISA based on IgY.

    Science.gov (United States)

    Nie, Ge; Wang, Ting; Lu, Shengjun; Liu, Wenqi; Li, Yonglong; Lei, Jiahui

    2014-01-01

    Clonorchiasis, caused by Clonorchis sinensis, is widely distributed in Southeast Asia including China. Clonorchiasis is included in control programs of neglected tropical diseases by World Health Organization (WHO) because it is one of the major health problems in most endemic areas. Diagnosis of clonorchiasis plays a key role in the control programs. However, so far, there is no satisfactory method for clonorchiasis because of low sensitivity, poor practicality and high false positivity of available diagnostic tools. We developed an immunomagnetic bead enzyme-linked immunosorbent assay (ELISA) based on IgY (egg yolk immunoglobulin) against cysteine proteinase of C. sinensis for detection of circulating antigen in serum samples of patients infected with C. sinensis. The polyclonal IgY, coated with magnetic beads, was used as a capture antibody and a monoclonal IgG labeled with horseradish peroxidase as a detection antibody in the IgY-based immunomagnetic bead ELISA system (IgY-IMB-ELISA). The results showed that the sensitivity of IgY-IMB-ELISA was 93.3% (14 of 15) in cases of heavy infection (5000 to 9999 eggs per gram feces, i.e, EPG 5000-9999), 86.7% (13 of 15) in cases of moderate infection (EPG 1000-4999) and 75.0% (9 of 12) in cases of light infection (EPG <1000) of clonorchiasis. Together 36 of total 42 (85.7%) serum samples of human clonorchiasis gave a positive reaction. There was a significant correlation between ELISA optical density and egg counts (EPG) with a correlation coefficient of 0.83 in total 42 patients. There were no positive results in patients with trichinosis (n = 10) or cysticercosis (n = 10). Cross-reactivity was 6.7% (2 of 30) with schistosomiasis japonica and 10.0% (3 of 30) with paragonimiasis, respectively. No positive reaction was found in 20 healthy persons. Our findings suggest that IgY-IMB-ELISA appears to be a sensitive and specific assay for detection of circulating antigen in human clonorchiasis.

  10. Development of a Nucleoprotein-Based Enzyme-Linked Immunosorbent Assay Using a Synthetic Peptide Antigen for Detection of Avian Metapneumovirus Antibodies in Turkey Sera

    Science.gov (United States)

    Alvarez, Rene; Njenga, M. Kariuki; Scott, Melissa; Seal, Bruce S.

    2004-01-01

    Avian metapneumoviruses (aMPV) cause an upper respiratory tract disease with low mortality but high morbidity, primarily in commercial turkeys, that can be exacerbated by secondary infections. There are three types of aMPV, of which type C is found only in the United States. The aMPV nucleoprotein (N) amino acid sequences of serotypes A, B, and C were aligned for comparative analysis. On the basis of the predicted antigenicity of consensus sequences, five aMPV-specific N peptides were synthesized for development of a peptide antigen enzyme-linked immunosorbent assay (aMPV N peptide-based ELISA) to detect aMPV-specific antibodies among turkeys. Sera from naturally and experimentally infected turkeys were used to demonstrate the presence of antibodies reactive to the chemically synthesized aMPV N peptides. Subsequently, aMPV N peptide 1, which had the sequence 10-DLSYKHAILKESQYTIKRDV-29, with variations at only three amino acids among aMPV serotypes, was evaluated as a universal aMPV ELISA antigen. Data obtained with the peptide-based ELISA correlated positively with total aMPV viral antigen-based ELISAs, and the peptide ELISA provided higher optical density readings. The results indicated that aMPV N peptide 1 can be used as a universal ELISA antigen to detect antibodies for all aMPV serotypes. PMID:15013970

  11. Performances of Four Helicobacter pylori Serological Detection Kits Using Stool Antigen Test as Gold Standard.

    Science.gov (United States)

    Biranjia-Hurdoyal, Susheela D; Seetulsingh-Goorah, Sharmila P

    2016-01-01

    The aim was to determine the performances of four Helicobacter pylori serological detection kits in different target groups, using Amplified IDEIA™ Hp StAR™ as gold standard. Kits studied were Rapid Immunochromatoghraphic Hexagon, Helicoblot 2.1, an EIA IgG kit and EIA IgA kit. Stool and blood samples were collected from 162 apparently healthy participants (control) and 60 Type 2 diabetes mellitus (T2DM) patients. The performances of the four serological detection kits were found to be affected by gender, age, health status and ethnicity of the participants. In the control group, the Helicoblot 2.1 kit had the best performance (AUC = 0.85; ppoor performances. In the T2DM subgroup, the kits H2.1 and EIA IgG had best performances, with accuracies of 96.5% and 93.1% respectively. The performance of EIA IgG improved with adjustment of its cut-off value. The performances of the detection kits were affected by various factors which should be taken into consideration.

  12. Performances of Four Helicobacter pylori Serological Detection Kits Using Stool Antigen Test as Gold Standard.

    Directory of Open Access Journals (Sweden)

    Susheela D Biranjia-Hurdoyal

    Full Text Available The aim was to determine the performances of four Helicobacter pylori serological detection kits in different target groups, using Amplified IDEIA™ Hp StAR™ as gold standard. Kits studied were Rapid Immunochromatoghraphic Hexagon, Helicoblot 2.1, an EIA IgG kit and EIA IgA kit.Stool and blood samples were collected from 162 apparently healthy participants (control and 60 Type 2 diabetes mellitus (T2DM patients.The performances of the four serological detection kits were found to be affected by gender, age, health status and ethnicity of the participants. In the control group, the Helicoblot 2.1 kit had the best performance (AUC = 0.85; p<0.05, accuracy = 86.4%, followed by EIA IgG (AUC = 0.75; p<0.05, accuracy = 75.2%. The Rapid Hexagon and EIA IgA kits had relatively poor performances. In the T2DM subgroup, the kits H2.1 and EIA IgG had best performances, with accuracies of 96.5% and 93.1% respectively. The performance of EIA IgG improved with adjustment of its cut-off value.The performances of the detection kits were affected by various factors which should be taken into consideration.

  13. Comparison of antigen detection and quantitative PCR in the detection of chlamydial infection in koalas (Phascolarctos cinereus).

    Science.gov (United States)

    Hanger, Jon; Loader, Joanne; Wan, Charles; Beagley, Kenneth W; Timms, Peter; Polkinghorne, Adam

    2013-03-01

    The gold standard method for detecting chlamydial infection in domestic and wild animals is PCR, but the technique is not suited to testing animals in the field when a rapid diagnosis is frequently required. The objective of this study was to compare the results of a commercially available enzyme immunoassay test for Chlamydia against a quantitative Chlamydia pecorum-specific PCR performed on swabs collected from the conjunctival sac, nasal cavity and urogenital sinuses of naturally infected koalas (Phascolarctos cinereus). The level of agreement for positive results between the two assays was low (43.2%). The immunoassay detection cut-off was determined as approximately 400 C. pecorum copies, indicating that the test was sufficiently sensitive to be used for the rapid diagnosis of active chlamydial infections. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. A simple and inexpensive point-of-care test for hepatitis B surface antigen detection: serological and molecular evaluation.

    Science.gov (United States)

    Gish, R G; Gutierrez, J A; Navarro-Cazarez, N; Giang, K; Adler, D; Tran, B; Locarnini, S; Hammond, R; Bowden, S

    2014-12-01

    Early identification of chronic hepatitis B is important for optimal disease management and prevention of transmission. Cost and lack of access to commercial hepatitis B surface antigen (HBsAg) immunoassays can compromise the effectiveness of HBV screening in resource-limited settings and among marginalized populations. High-quality point-of-care (POC) testing may improve HBV diagnosis in these situations. Currently available POC HBsAg assays are often limited in sensitivity. We evaluated the NanoSign(®) HBs POC chromatographic immunoassay for its ability to detect HBsAg of different genotypes and with substitutions in the 'a' determinant. Thirty-seven serum samples from patients with HBV infection, covering HBV genotypes A-G, were assessed for HBsAg titre with the Roche Elecsys HBsAg II quantification assay and with the POC assay. The POC assay reliably detected HBsAg at a concentration of at least 50 IU/mL for all genotypes, and at lower concentrations for some genotypes. Eight samples with substitutions in the HBV 'a' determinant were reliably detected after a 1/100 dilution. The POC strips were used to screen serum samples from 297 individuals at risk for HBV in local clinical settings (health fairs and outreach events) in parallel with commercial laboratory HBsAg testing (Quest Diagnostics EIA). POC testing was 73.7% sensitive and 97.8% specific for detection of HBsAg. Although the POC test demonstrated high sensitivity over a range of genotypes, false negatives were frequent in a clinical setting. Nevertheless, the POC assay offers advantages for testing in both developed and resource-limited countries due to its low cost (0.50$) and immediately available results. © 2014 John Wiley & Sons Ltd.

  15. Prostate-specific membrane antigen PET/MRI validation of MR textural analysis for detection of transition zone prostate cancer

    International Nuclear Information System (INIS)

    Bates, Anthony; Miles, Kenneth

    2017-01-01

    To validate MR textural analysis (MRTA) for detection of transition zone (TZ) prostate cancer through comparison with co-registered prostate-specific membrane antigen (PSMA) PET-MR. Retrospective analysis was performed for 30 men who underwent simultaneous PSMA PET-MR imaging for staging of prostate cancer. Thirty texture features were derived from each manually contoured T2-weighted, transaxial, prostatic TZ using texture analysis software that applies a spatial band-pass filter and quantifies texture through histogram analysis. Texture features of the TZ were compared to PSMA expression on the corresponding PET images. The Benjamini-Hochberg correction controlled the false discovery rate at <5%. Eighty-eight T2-weighted images in 18 patients demonstrated abnormal PSMA expression within the TZ on PET-MR. 123 images were PSMA negative. Based on the corrected p-value of 0.005, significant differences between PSMA positive and negative slices were found for 16 texture parameters: Standard deviation and mean of positive pixels for all spatial filters (p = <0.0001 for both at all spatial scaling factor (SSF) values) and mean intensity following filtration for SSF 3-6 mm (p = 0.0002-0.0018). Abnormal expression of PSMA within the TZ is associated with altered texture on T2-weighted MR, providing validation of MRTA for the detection of TZ prostate cancer. (orig.)

  16. Prostate-specific membrane antigen PET/MRI validation of MR textural analysis for detection of transition zone prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Bates, Anthony [Princess Alexandra Hospital, Brisbane (Australia); Miles, Kenneth [Princess Alexandra Hospital, Department of Diagnostic Radiology, Brisbane, QLD (Australia); University College London, Institute of Nuclear Medicine, London (United Kingdom)

    2017-12-15

    To validate MR textural analysis (MRTA) for detection of transition zone (TZ) prostate cancer through comparison with co-registered prostate-specific membrane antigen (PSMA) PET-MR. Retrospective analysis was performed for 30 men who underwent simultaneous PSMA PET-MR imaging for staging of prostate cancer. Thirty texture features were derived from each manually contoured T2-weighted, transaxial, prostatic TZ using texture analysis software that applies a spatial band-pass filter and quantifies texture through histogram analysis. Texture features of the TZ were compared to PSMA expression on the corresponding PET images. The Benjamini-Hochberg correction controlled the false discovery rate at <5%. Eighty-eight T2-weighted images in 18 patients demonstrated abnormal PSMA expression within the TZ on PET-MR. 123 images were PSMA negative. Based on the corrected p-value of 0.005, significant differences between PSMA positive and negative slices were found for 16 texture parameters: Standard deviation and mean of positive pixels for all spatial filters (p = <0.0001 for both at all spatial scaling factor (SSF) values) and mean intensity following filtration for SSF 3-6 mm (p = 0.0002-0.0018). Abnormal expression of PSMA within the TZ is associated with altered texture on T2-weighted MR, providing validation of MRTA for the detection of TZ prostate cancer. (orig.)

  17. Early diagnosis of dengue in travelers: comparison of a novel real-time RT-PCR, NS1 antigen detection and serology.

    Science.gov (United States)

    Huhtamo, Eili; Hasu, Essi; Uzcátegui, Nathalie Y; Erra, Elina; Nikkari, Simo; Kantele, Anu; Vapalahti, Olli; Piiparinen, Heli

    2010-01-01

    The increased traveling to dengue endemic regions and the numerous epidemics have led to a rise in imported dengue. The laboratory diagnosis of acute dengue requires several types of tests and often paired samples are needed for obtaining reliable results. Although several diagnostic methods are available, proper comparative data on their performance are lacking. To compare the performance of novel methods including a novel pan-DENV real-time RT-PCR and a commercially available NS1 capture-EIA in regard to IgM detection for optimizing the early diagnosis of DENV in travelers. A panel of 99 selected early phase serum samples of dengue patients was studied by real-time RT-PCR, NS1 antigen ELISA, IgM-EIA, IgG-IFA and cell culture virus isolation. The novel real-time RT-PCR was shown specific and sensitive for detection of DENV-1-4 RNA and suitable for diagnostic use. The diagnostic rate using combination of RNA and IgM detection was 99% and using NS1 and IgM detection 95.9%. The results of RNA and NS1 antigen detection disagreed in 15.5% of samples that had only RNA or NS1 antigen detected. The diagnostic rates of early samples are higher when either RNA or NS1 antigen detection is combined with IgM detection. Besides the differences in the RNA and NS1 detection assays, the observed discrepancy of results could suggest individual variation or differences in timing of these markers in patient serum. Copyright (c) 2009 Elsevier B.V. All rights reserved.

  18. Comparison of a Stool Antigen Detection Kit and PCR for Diagnosis of Entamoeba histolytica and Entamoeba dispar Infections in Asymptomatic Cyst Passers in Iran

    OpenAIRE

    Solaymani-Mohammadi, Shahram; Rezaian, Mostafa; Babaei, Zahra; Rajabpour, Azam; Meamar, Ahmad R.; Pourbabai, Ahmad A.; Petri, William A.

    2006-01-01

    The present study was conducted to compare stool antigen detection with PCR for the diagnosis of Entamoeba sp. infection in asymptomatic cyst passers from Iran. Entamoeba dispar and, in one case, E. moshkovskii were the Entamoeba spp. found in the amebic cyst passers. There was a 100% correlation between the results from the TechLab E. histolytica II stool antigen kit and those from nested PCR. We concluded that E. dispar is much more common in asymptomatic cyst passers in Iran and that antig...

  19. Detection of H5 Avian Influenza Viruses by Antigen-Capture Enzyme-Linked Immunosorbent Assay Using H5-Specific Monoclonal Antibody▿

    OpenAIRE

    He, Qigai; Velumani, Sumathy; Du, Qingyun; Lim, Chee Wee; Ng, Fook Kheong; Donis, Ruben; Kwang, Jimmy

    2007-01-01

    The unprecedented spread of highly pathogenic avian influenza virus subtype H5N1 in Asia and Europe is threatening animals and public health systems. Effective diagnosis and control management are needed to control the disease. To this end, we developed a panel of monoclonal antibodies (MAbs) against the H5N1 avian influenza virus (AIV) and implemented an antigen-capture enzyme-linked immunosorbent assay (AC-ELISA) to detect the H5 viral antigen. Mice immunized with denatured hemagglutinin (H...

  20. Comparison of two solid-phase radioimmunoassay systems and a reverse passive haemagglutination test for the detection of hepatitis B surface antigen

    International Nuclear Information System (INIS)

    Hui, Z.; Coulepis, A.G.; Gust, I.D.

    1982-01-01

    The sensitivity and specificity of two commercially available radioimmunosay tests (Austria II-125, Abbott Laboratories; and International CIS, Commissariat Alenergie Atomique-Oris Laboratoire des Produits Biomedicaux) and a reverse passive haemagglutination test (Hepatest, Wellcome) for detection of hepatitis B surface antigen were evaluated using the Australian hepatitis B reference panel of 25 sera, and a panel of 257 sera collected from patients with acute hepatitis B, chronic carriers of hepatitis B surface antigen and two populations in which hepatitis B virus infection is known to be endemic. The three techniques were found to be generally comparable in sensitivity and specificity. The advantages and disadvantages of each method are discussed

  1. Detection of cell-associated or soluble antigens of Legionella pneumophila serogroups 1 to 6, Legionella bozemanii, Legionella dumoffii, Legionella gormanii, and Legionella micdadei by staphylococcal coagglutination tests.

    OpenAIRE

    Wilkinson, H W; Fikes, B J

    1981-01-01

    Current methods used for the detection of whole-cell isolates of Legionella or for the detection of Legionella soluble antigens are technically impractical for many clinical laboratories. The purpose of this study was to explore practical alternatives. The results showed that whole cell isolates of Legionella pneumophila serogroups 1 to 6, Legionella bozemanii, Legionella dumoffii, Legionella gormanii, and Legionella micdadei were identified specifically by a simple slide agglutination test o...

  2. Schistosoma mansoni Phosphoenolpyruvate Carboxykinase, a Novel Egg Antigen: Immunological Properties of the Recombinant Protein and Identification of a T-Cell Epitope

    OpenAIRE

    Asahi, Hiroko; Osman, Ahmed; Cook, Rosemary M.; LoVerde, Philip T.; Stadecker, Miguel J.

    2000-01-01

    In schistosomiasis mansoni, hepatic granulomatous inflammation surrounding parasite eggs is mediated by CD4+ T helper (Th) cells sensitized to schistosomal egg antigens (SEA). We previously showed that a prominent lymphoproliferative response of CD4+ Th cells from schistosome-infected C57BL/6 (BL/6) mice was directed against a 62-kDa component of SEA. A partial amino acid sequence of the 62-kDa component was found to be identical with one present in the enzyme phosphoenolpyruvate carboxykinas...

  3. Developments of sensitive immunoassays for detection of antibodies against hepatitis B surface antigen

    Energy Technology Data Exchange (ETDEWEB)

    Ionescu-Matiu, I; Sanchez, Y; Dreesman, G R [Baylor Univ., Houston, TX (USA). Coll. of Medicine; Fields, H A [Centers for Disease Control, Public Health Service, Department of Health and Human Services, Phoenix, AZ (USA)

    1983-01-01

    Three micro solid phase immunoassays (a micro-SPRIA and two ELISA techniques) were developed and tested for the detection of anti-HBs antibodies. Two different crosslinkers (glutaraldehyde and N-succinimidyl 3-(2-pyridyldithio) propionate) were used to couple a goat anti-mouse IgG reagent to alkaline phosphatase for use as enzyme-labeled probes in the two ELISA tests. With the latter cross-linker, a defined conjugate with a 1 : 1 antibody-enzyme molar ratio was obtained. The sensitivities of micro-SPRIA and the two types of ELISA were compared to that of the commercial solid phase radioimmunoassay AUSAB test. All three microtests were significantly more sensitive than the AUSAB test. The ELISA using the glutaraldehyde cross-linked conjugate was 3-5 times less sensitive than micro-SPRIA, while the ELISA using the disulfide-linked conjugate was 2.6-4.0 times more sensitive than micro-SPRIA.

  4. Detection of Antibody to Envelope (E2 Antigen of Hepatitis C Virus

    Directory of Open Access Journals (Sweden)

    RK Chaudhary

    1997-01-01

    Full Text Available One hundred and four clinical specimens from provincial public health laboratories were tested for antibody to hepatitis C virus (HCV envelope protein (anti-E2. To evaluate the effect of hypervariability of E2 region on anti-E2 assay, 49 recombinant immunoblot assay (RIBA 3.0 positive samples were genotyped. All 49 genotyped samples were positive for anti-E2. Eight of 12 (67% indeterminate, HCV RNA positive samples were anti-E2 reactive. Nine of 30 (30% indeterminate, HCV RNA negative samples were also positive for anti-E2. Anti-E2 was detected in two of 13 (15% RIBA-negative and enzyme immunoassays-positive samples. Although small number of samples were tested, the results showed that it may be possible to resolve indeterminate samples with the anti-E2 assay.

  5. Paraneoplastic antigen Ma2 autoantibodies as specific blood biomarkers for detection of early recurrence of small intestine neuroendocrine tumors.

    Science.gov (United States)

    Cui, Tao; Hurtig, Monica; Elgue, Graciela; Li, Su-Chen; Veronesi, Giulia; Essaghir, Ahmed; Demoulin, Jean-Baptiste; Pelosi, Giuseppe; Alimohammadi, Mohammad; Öberg, Kjell; Giandomenico, Valeria

    2010-12-30

    Small intestine neuroendocrine tumors (SI-NETs) belong to a rare group of cancers. Most patients have developed metastatic disease at the time of diagnosis, for which there is currently no cure. The delay in diagnosis is a major issue in the clinical management of the patients and new markers are urgently needed. We have previously identified paraneoplastic antigen Ma2 (PNMA2) as a novel SI-NET tissue biomarker. Therefore, we evaluated whether Ma2 autoantibodies detection in the blood stream is useful for the clinical diagnosis and recurrence of SI-NETs. A novel indirect ELISA was set up to detect Ma2 autoantibodies in blood samples of patients with SI-NET at different stages of disease. The analysis was extended to include typical and atypical lung carcinoids (TLC and ALC), to evaluate whether Ma2 autoantibodies in the blood stream become a general biomarker for NETs. In total, 124 blood samples of SI-NET patients at different stages of disease were included in the study. The novel Ma2 autoantibody ELISA showed high sensitivity, specificity and accuracy with ROC curve analysis underlying an area between 0.734 and 0.816. Ma2 autoantibodies in the blood from SI-NET patients were verified by western blot and sequential immunoprecipitation. Serum antibodies of patients stain Ma2 in the tumor tissue and neurons. We observed that SI-NET patients expressing Ma2 autoantibody levels below the cutoff had a longer progression and recurrence-free survival compared to those with higher titer. We also detected higher levels of Ma2 autoantibodies in blood samples from TLC and ALC patients than from healthy controls, as previously shown in small cell lung carcinoma samples. Here we show that high Ma2 autoantibody titer in the blood of SI-NET patients is a sensitive and specific biomarker, superior to chromogranin A (CgA) for the risk of recurrence after radical operation of these tumors.

  6. Host immunity, nutrition and coinfection alter longitudinal infection patterns of schistosomes in a free ranging African buffalo population.

    Directory of Open Access Journals (Sweden)

    Brianna R Beechler

    2017-12-01

    Full Text Available Schistosomes are trematode parasites of global importance, causing infections in millions of people, livestock, and wildlife. Most studies on schistosomiasis, involve human subjects; as such, there is a paucity of longitudinal studies investigating parasite dynamics in the absence of intervention. As a consequence, despite decades of research on schistosomiasis, our understanding of its ecology in natural host populations is centered around how environmental exposure and acquired immunity influence acquisition of parasites, while very little is known about the influence of host physiology, coinfection and clearance in the absence of drug treatment. We used a 4-year study in free-ranging African buffalo to investigate natural schistosome dynamics. We asked (i what are the spatial and temporal patterns of schistosome infections; (ii how do parasite burdens vary over time within individual hosts; and (iii what host factors (immunological, physiological, co-infection and environmental factors (season, location explain patterns of schistosome acquisition and loss in buffalo? Schistosome infections were common among buffalo. Microgeographic structure explained some variation in parasite burdens among hosts, indicating transmission hotspots. Overall, parasite burdens ratcheted up over time; however, gains in schistosome abundance in the dry season were partially offset by losses in the wet season, with some hosts demonstrating complete clearance of infection. Variation among buffalo in schistosome loss was associated with immunologic and nutritional factors, as well as co-infection by the gastrointestinal helminth Cooperia fuelleborni. Our results demonstrate that schistosome infections are surprisingly dynamic in a free-living mammalian host population, and point to a role for host factors in driving variation in parasite clearance, but not parasite acquisition which is driven by seasonal changes and spatial habitat utilization. Our study illustrates

  7. Grafting of a peptide probe for Prostate-Specific Antigen detection using diazonium electroreduction and click chemistry.

    Science.gov (United States)

    Strzemińska, I; Sainte Rose Fanchine, S; Anquetin, G; Reisberg, S; Noël, V; Pham, M C; Piro, B

    2016-07-15

    The main objective of this work was to validate a label-free electrochemical method of protein detection using peptides as capture probes. As a proof-of-concept, we used a 7 amino acids sequence (HSSKLQL) specific for Prostate Specific Antigen. We investigated various electrografting conditions of two anilines (2-[(4-aminophenyl)sulfanyl]-8-hydroxy-1,4-naphthoquinone and 4-azidoaniline) further converted in situ into their corresponding diazonium salts on glassy carbon electrodes. It was demonstrated that the best method to obtain a mixed layer is the simultaneous electroreduction of the two diazonium salts. 4-azidoaniline was used to covalently immobilize the ethynyl-functionalized peptide probe by click coupling, and the hydroxynaphthoquinone derivative plays the role of electrochemical transducer of the peptide-protein recognition. The proteolytic activity of PSA towards a small peptide substrate carrying streptavidin at its distal end was also investigated to design an original sensing architecture leading to a reagentless, label free, and "signal-on" PSA sensor. Without optimization, the limit of quantification can be estimated in the nM to pM range. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Evaluation of a rapid immunochromatographic ODK-0901 test for detection of pneumococcal antigen in middle ear fluids and nasopharyngeal secretions.

    Directory of Open Access Journals (Sweden)

    Muneki Hotomi

    Full Text Available Since the incidence of penicillin-resistant Streptococcus pneumoniae has been increasing at an astonishing rate throughout the world, the need for accurate and rapid identification of pneumococci has become increasingly important to determine the appropriate antimicrobial treatment. We have evaluated an immunochromatographic test (ODK-0901 that detects pneumococcal antigens using 264 middle ear fluids (MEFs and 268 nasopharyngeal secretions (NPSs. A sample was defined to contain S. pneumoniae when optochin and bile sensitive alpha hemolytic streptococcal colonies were isolated by culture. The sensitivity and specificity of the ODK-0901 test were 81.4% and 80.5%, respectively, for MEFs from patients with acute otitis media (AOM. In addition, the sensitivity and specificity were 75.2% and 88.8%, respectively, for NPSs from patients with acute rhinosinusitis. The ODK-0901 test may provide a rapid and highly sensitive evaluation of the presence of S. pneumoniae and thus may be a promising method of identifying pneumococci in MEFs and NPSs.

  9. Comparison of Real Time Polymerase Chain Reaction with Microscopy and Antigen Detection Assay for the Diagnosis of Malaria

    International Nuclear Information System (INIS)

    Khan, S. A.; Ahmed, S.; Khan, F. A.; Shamshad, G. U.; Joyia, Z.; Mushahid, N.; Saeed, S.

    2013-01-01

    Objective: To determine the sensitivity of a real time polymerase chain reaction (PCR) for malaria diagnosis and to compare its accuracy with microscopy and an antigen based rapid diagnostic test (OptiMal). Study Design: Cross-sectional analytical study. Place and Duration of Study: Military Hospital, Armed Forces Institute of Transfusion and Armed Forces Institute of Pathology, Rawalpindi, from July to December 2011. Methodology: Venous blood samples of 300 clinically suspected patients of malaria were tested for malaria parasite by microscopy and OptiMal; and malaria parasite index was calculated for the positive samples. Plasmodium genus specific real time PCR was performed on all specimens, targeting small subunit rRNA gene. Diagnostic accuracy of three tests was compared and cost analysis was done. Results: Out of 300 patients, malaria parasite was detected in 110, 106 and 123 patients by microscopy, OptiMAL and PCR respectively. Real time PCR was 100% sensitive while microscopy and OptiMal had sensitivity of 89.4% and 86.2% respectively. All methods were 100% specific. The cost per test was calculated to be 0.2, 2.75 and 3.30 US dollar by microscopy, OptiMal and PCR respectively, excluding the once capital cost on PCR equipment. Conclusion: Genus specific real time PCR for the diagnosis of malaria was successfully established as a highly sensitive and affordable technology that should be incorporated in the diagnostic algorithm in this country. (author)

  10. [Use of Rapid Antigen Detection Test (RADT) among general practitioner teachers at the Paris Descartes University: 2005-2007].

    Science.gov (United States)

    Cornaglia, C; Robinet, J; Partouche, H

    2009-06-01

    The distribution of the Rapid Antigen Detection Test (RADT) and the National Health Insurance's information campaign should efficiently reduce the unjustified use antibiotic. However, a preliminary survey among GP trainers at the Paris Descartes University indicated that the RADT was seldom used. This study had for aim to describe the RADT use trend among trainers since 2005 and the main obstacles to its widespread use, and to assess the Mac Isaac score use and antibiotic prescriptions. Between February and May 2007, a survey was carried out among 66 GPs who were required to report their first ten patients over three years of age presenting with pharyngitis. RADT use and antibiotic prescriptions were compared with those of the 2005 survey. RADT use had decreased (52.5% [48.2-56.8] versus 57.5% [52.1-68.8], p<0.05). GPs did not use the RADT because they considered it "useless in decision making". Clinical findings were sufficient in most cases. The Mac Isaac score was not widely used by GPs (28.3%) and antibiotic prescription had increased except for macrolides which had decreased (10% vs 15%). Among patients with a negative RADT, 11.9% (vs 10.5% en 2005, p<0.001) were prescribed antibiotics. The RADT use decreased in two years among GP trainers. GPs still prescribe treatment according to clinical findings, most without using diagnostic tools.

  11. Acute toxemic schistosomiasis complicated by a acute flaccid paraplegia due to schistosomal myeloradiculopathy in Sudan

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Abdelmonim F [Dept. of Medicine, Faculty of Medicine, Taibah Univ., Al-Madinah Al-Munwarah (Saudi Arabia); Kareem, Abid M [Dept. of Gastroenterology, King Fahd Hospital, Al- Madinah Al-Munwarah (Saudi Arabia); Dawoud, Talal A [Dept. of Neurology, King Fahd Hospital, Al-Madinah Al-Munawarh (Saudi Arabia); Idris, Abdelrehman S [Dept. of Neurology, Hiraa Hospital, Mecca (Saudi Arabia)

    2008-07-01

    A 55-year old Sudanese physician presented with one month history of diarrhea, loss of weight 10 kg and low grade nocturnal fever. Following colonoscopy, he rapidly developed paraparesis and retention of urine. Magnetic resonance imaging (MRI) of the spinal cord showed low cord lesion suggestive of transverse myelitis. We present a detailed account of diagnostic and management challenges and a literature review of the final diagnosis of acute toxemic schistosomiasis, complicated by acute flaccid paraplegia due to schistosomal myeloradiculopathy. We are reporting this case to increase the awareness of physicians of schistosomal myeloradiculopathy, as it needs urgent specific treatment praziquantel and steroids. An early follow-up with MRI of the spinal cord 2 weeks treatment may help in preventing unnecessary neurosurgical intervention. Bilharziasis may be contracted on the banks of river White Nile in urban areas. Finally clinicians should make use of the Google search for diagnosis in difficult cases. (author)

  12. Change in schistosome sex ratio under the influence of a biotic environmental-related factor.

    Science.gov (United States)

    Moné, H

    1997-04-01

    Schistosoma mansoni is a dioecious trematode responsible for intestinal schistosomiasis in man. The sex ratio was determined for S. mansoni adults derived from cercariae obtained from infected Biomphalaria glabrata maintained in the presence of the nonvector molluse. Marisa cornuarietis. The presence of M. cornuarietis is responsible for enhanced growth of B. glabrata and for a change in the sex ratio of the schistosome, which becomes more male-biased as compared to control snails maintained in aquaria lacking M. cornuarietis. This is the first time the presence of another species in the environment has been shown to influence schistosome sex ratios. Two nonexclusive hypotheses are proposed to explain this variation in the sex ratio: sexual competition between male and female sporocysts; and sex reversal.

  13. Acute toxemic schistosomiasis complicated by a acute flaccid paraplegia due to schistosomal myeloradiculopathy in Sudan

    International Nuclear Information System (INIS)

    Ahmed, Abdelmonim F.; Kareem, Abid M.; Dawoud, Talal A.; Idris, Abdelrehman S.

    2008-01-01

    A 55-year old Sudanese physician presented with one month history of diarrhea, loss of weight 10 kg and low grade nocturnal fever. Following colonoscopy, he rapidly developed paraparesis and retention of urine. Magnetic resonance imaging (MRI) of the spinal cord showed low cord lesion suggestive of transverse myelitis. We present a detailed account of diagnostic and management challenges and a literature review of the final diagnosis of acute toxemic schistosomiasis, complicated by acute flaccid paraplegia due to schistosomal myeloradiculopathy. We are reporting this case to increase the awareness of physicians of schistosomal myeloradiculopathy, as it needs urgent specific treatment praziquantel and steroids. An early follow-up with MRI of the spinal cord 2 weeks treatment may help in preventing unnecessary neurosurgical intervention. Bilharziasis may be contracted on the banks of river White Nile in urban areas. Finally clinicians should make use of the Google search for diagnosis in difficult cases. (author)

  14. Study of bacterial meningitis in children below 5 years with comparative evaluation of gram staining, culture and bacterial antigen detection.

    Science.gov (United States)

    Yadhav Ml, Kala

    2014-04-01

    Bacterial meningitis is one of the most serious infections seen in infants and children, which is associated with acute complications and chronic morbidity. Infections of Central Nervous System (CNS) still dominate the scene of childhood neurological disorders in most of the developing tropical countries. To isolate, identify and determine the antibiotic susceptibility patterns of pathogens associated with bacterial meningitis. We also aimed to comparatively evaluate of Gram staining, culture and bacterial antigen detection in cerebrospinal fluid samples. Present comparative study included 100 CSF samples of children below the age of 5 years, who were clinically suspected meningitis cases. The samples were subjected to Gram staining, culture and Latex agglutination test (LAT). The organisms isolated in the study were characterized and antibiotic susceptibility test was done according to standard guidelines. It was done by using Gaussian test. Of the 100 cases, 24 were diagnosed as Acute bacterial meningitis (ABM) cases by. Gram staining, culture and latex agglutination test. 21 (87.5%) cases were culture positive, with 2 cases being positive for polymicrobial isolates. Gram staining was positive in 17 (70.53%) cases and LAT was positive in 18 (33.33%) cases. Streptococcus pneumoniae was the predominant organism which was isolated and it was sensitive to antibiotics. In the present study, male to female ratio was 1.27:1, which showed a male preponderance. With the combination of Gram staining, culture, and LAT, 100% sensitivity and specificity can be achieved (p Gram staining and LAT can detect 85% of cases of ABM. Bacterial meningitis is a medical emergency and making an early diagnosis and providing treatment early are life saving and they reduce chronic morbidity.

  15. Detection of polyomavirus simian virus 40 tumor antigen DNA in AIDS-related systemic non-Hodgkin lymphoma

    Science.gov (United States)

    Vilchez, Regis A.; Lednicky, John A.; Halvorson, Steven J.; White, Zoe S.; Kozinetz, Claudia A.; Butel, Janet S.

    2002-01-01

    Systemic non-Hodgkin lymphoma (S-NHL) is a common malignancy during HIV infection, and it is hypothesized that infectious agents may be involved in the etiology. Epstein-Barr virus DNA is found in <40% of patients with AIDS-related S-NHL, suggesting that other oncogenic viruses, such as polyomaviruses, may play a role in pathogenesis. We analyzed AIDS-related S-NHL samples, NHL samples from HIV-negative patients, peripheral blood leukocytes from HIV-infected and -uninfected patients without NHL, and lymph nodes without tumors from HIV-infected patients. Specimens were examined by polymerase chain reaction analysis with use of primers specific for an N-terminal region of the oncoprotein large tumor antigen ( T-ag ) gene conserved among all three polyomaviruses (simian virus 40 [SV40], JC virus, and BK virus). Polyomavirus T-ag DNA sequences, proven to be SV40-specific, were detected more frequently in AIDS-related S-NHL samples (6 of 26) than in peripheral blood leukocytes from HIV-infected patients (6 of 26 vs. 0 of 69; p =.0001), NHL samples from HIV-negative patients (6 of 26 vs. 0 of 10; p =.09), or lymph nodes (6 of 26 vs. 0 of 7; p =.16). Sequences of C-terminal T-ag DNA from SV40 were amplified from two AIDS-related S-NHL samples. Epstein-Barr virus DNA sequences were detected in 38% (10 of 26) AIDS-related S-NHL samples, 50% (5 of 10) HIV-negative S-NHL samples, and 57% (4 of 7) lymph nodes. None of the S-NHL samples were positive for both Epstein-Barr virus DNA and SV40 DNA. Further studies of the possible role of SV40 in the pathogenesis of S-NHL are warranted.

  16. Neurotransmitter transporters in schistosomes: structure, function and prospects for drug discovery.

    Science.gov (United States)

    Ribeiro, Paula; Patocka, Nicholas

    2013-12-01

    Neurotransmitter transporters (NTTs) play a fundamental role in the control of neurotransmitter signaling and homeostasis. Sodium symporters of the plasma membrane mediate the cellular uptake of neurotransmitter from the synaptic cleft, whereas proton-driven vesicular transporters sequester the neurotransmitter into synaptic vesicles for subsequent release. Together these transporters control how much transmitter is released and how long it remains in the synaptic cleft, thereby regulating the intensity and duration of signaling. NTTs have been the subject of much research in mammals and there is growing interest in their activities among invertebrates as well. In this review we will focus our attention on NTTs of the parasitic flatworm Schistosoma mansoni. Bloodflukes of the genus Schistosoma are the causative agents of human schistosomiasis, a devastating disease that afflicts over 200 million people worldwide. Schistosomes have a well-developed nervous system and a rich diversity of neurotransmitters, including many of the small-molecule ("classical") neurotransmitters that normally employ NTTs in their mechanism of signaling. Recent advances in schistosome genomics have unveiled numerous NTTs in this parasite, some of which have now been cloned and characterized in vitro. Moreover new genetic and pharmacological evidence suggests that NTTs are required for proper control of neuromuscular signaling and movement of the worm. Among these carriers are proteins that have been successfully targeted for drug discovery in other organisms, in particular sodium symporters for biogenic amine neurotransmitters such as serotonin and dopamine. Our goal in this chapter is to review the current status of research on schistosome NTTs, with emphasis on biogenic amine sodium symporters, and to evaluate their potential for anti-schistosomal drug targeting. Through this discussion we hope to draw attention to this important superfamily of parasite proteins and to identify new

  17. Schistosomes infection rate in relation to environmental factors in school children.

    Science.gov (United States)

    Raja'a, Y A; Assiragi, H M; Abu-Luhom, A A; Mohammed, A B; Albahr, M H; Ashaddadi, M A; Al Muflihi, A N

    2000-07-01

    An epidemiological comparative survey aimed at determination of prevalence and focal distribution of Schistosomes infection and intestinal parasites to provide a reference for evaluating the need for community intervention. All children of 14th October Primary School were involved. The children were from 7 villages that lie on the Assahul valley of lbb governorates in Yemen. The total number was 230 with (82%) boys and (18%) girls. Their age was between 5-18 years with a mean of 10.24 +/- 2.6 years. Millipore and modified Kato techniques were adopted to quantify urinary and intestinal Schistosomes eggs. Other ova, larvae, cysts were recorded whenever seen. It was revealed that there was a Schistosomes infection rate of 37%. The mansoni prevalence was 35%, hematobia was 5% and mixed infections were 3%. Light infection was classified among 17% of all children; moderate infection among 18% and no intense mansoni infection was determined. Whereas in the case of hematobia species, 2% were intense and 3% were light. Intensity in all children was 5% eggs/g feces in case of intestinal bilharzia and 1% egg/10 ml urine in case of urinary. With regard to the prevalence of any soil-transmitted parasites, it was found to be 69% (Ascariosis 68%, Trichuriosis 10%). Double infection was found in 10%. Hookworm eggs were not seen. Infection rates with other parasites were as follows: Giardiosis 18%, Amoebiosis 14%, ova of Hymenolepes nana were seen in 13%, Taeniosis affected 13% and E. Vermicularis 1%. Bivariate analysis revealed significant associations between Schistosomes infection with residence near the valley, male sex and frequent water contact activities. No significant association was found with the age of the child, parents' education, availability of latrine or household standpipe water. In conclusion, schistosomosis was moderate, whereas soil transmitted helminthosis were intense.

  18. Discovery and molecular characterization of a Bcl-2-regulated cell death pathway in schistosomes.

    Science.gov (United States)

    Lee, Erinna F; Clarke, Oliver B; Evangelista, Marco; Feng, Zhiping; Speed, Terence P; Tchoubrieva, Elissaveta B; Strasser, Andreas; Kalinna, Bernd H; Colman, Peter M; Fairlie, W Douglas

    2011-04-26

    Schistosomiasis is an infectious disease caused by parasites of the phylum platyhelminthe. Here, we describe the identification and characterization of a Bcl-2-regulated apoptosis pathway in Schistosoma japonicum and S. mansoni. Genomic, biochemical, and cell-based mechanistic studies provide evidence for a tripartite pathway, similar to that in humans including BH3-only proteins that are inhibited by prosurvival Bcl-2-like molecules, and Bax/Bak-like proteins that facilitate mitochondrial outer-membrane permeabilization. Because Bcl-2 proteins have been successfully targeted with "BH3 mimetic" drugs, particularly in the treatment of cancer, we investigated whether schistosome apoptosis pathways could provide targets for future antischistosomal drug discovery efforts. Accordingly, we showed that a schistosome prosurvival protein, sjA, binds ABT-737, a well-characterized BH3 mimetic. A crystal structure of sjA bound to a BH3 peptide provides direct evidence for the feasibility of developing BH3 mimetics to target Bcl-2 prosurvival proteins in schistosomes, suggesting an alternative application for this class of drugs beyond cancer treatment.

  19. Discovery and molecular characterization of a Bcl-2–regulated cell death pathway in schistosomes

    Science.gov (United States)

    Lee, Erinna F.; Clarke, Oliver B.; Evangelista, Marco; Feng, Zhiping; Speed, Terence P.; Tchoubrieva, Elissaveta B.; Strasser, Andreas; Kalinna, Bernd H.; Colman, Peter M.; Fairlie, W. Douglas

    2011-01-01

    Schistosomiasis is an infectious disease caused by parasites of the phylum platyhelminthe. Here, we describe the identification and characterization of a Bcl-2–regulated apoptosis pathway in Schistosoma japonicum and S. mansoni. Genomic, biochemical, and cell-based mechanistic studies provide evidence for a tripartite pathway, similar to that in humans including BH3-only proteins that are inhibited by prosurvival Bcl-2–like molecules, and Bax/Bak-like proteins that facilitate mitochondrial outer-membrane permeabilization. Because Bcl-2 proteins have been successfully targeted with “BH3 mimetic” drugs, particularly in the treatment of cancer, we investigated whether schistosome apoptosis pathways could provide targets for future antischistosomal drug discovery efforts. Accordingly, we showed that a schistosome prosurvival protein, sjA, binds ABT-737, a well-characterized BH3 mimetic. A crystal structure of sjA bound to a BH3 peptide provides direct evidence for the feasibility of developing BH3 mimetics to target Bcl-2 prosurvival proteins in schistosomes, suggesting an alternative application for this class of drugs beyond cancer treatment. PMID:21444803

  20. Exploring the function of protein kinases in schistosomes: perspectives from the laboratory and from comparative genomics

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    Anthony John Walker

    2014-07-01

    Full Text Available Eukaryotic protein kinases are well conserved through evolution. The genome of Schistosoma mansoni, which causes intestinal schistosomiasis, encodes over 250 putative protein kinases with all of the main eukaryotic groups represented. However, unraveling functional roles for these kinases is a considerable endeavour, particularly as protein kinases regulate multiple and sometimes overlapping cell and tissue functions in organisms. In this article, elucidating protein kinase signal transduction and function in schistosomes is considered from the perspective of the state-of-the-art methodologies used and comparative organismal biology, with a focus on current advances and future directions. Using the free-living nematode Caenorhabditis elegans as a comparator we predict roles for various schistosome protein kinases in processes vital for host invasion and successful parasitism such as sensory behaviour, growth and development. It is anticipated that the characterization of schistosome protein kinases in the context of parasite function will catalyze cutting edge research into host-parasite interactions and will reveal new targets for developing drug interventions against human schistosomiasis.

  1. Paraneoplastic antigen Ma2 autoantibodies as specific blood biomarkers for detection of early recurrence of small intestine neuroendocrine tumors.

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    Tao Cui

    Full Text Available BACKGROUND: Small intestine neuroendocrine tumors (SI-NETs belong to a rare group of cancers. Most patients have developed metastatic disease at the time of diagnosis, for which there is currently no cure. The delay in diagnosis is a major issue in the clinical management of the patients and new markers are urgently needed. We have previously identified paraneoplastic antigen Ma2 (PNMA2 as a novel SI-NET tissue biomarker. Therefore, we evaluated whether Ma2 autoantibodies detection in the blood stream is useful for the clinical diagnosis and recurrence of SI-NETs. METHODOLOGY/PRINCIPAL FINDINGS: A novel indirect ELISA was set up to detect Ma2 autoantibodies in blood samples of patients with SI-NET at different stages of disease. The analysis was extended to include typical and atypical lung carcinoids (TLC and ALC, to evaluate whether Ma2 autoantibodies in the blood stream become a general biomarker for NETs. In total, 124 blood samples of SI-NET patients at different stages of disease were included in the study. The novel Ma2 autoantibody ELISA showed high sensitivity, specificity and accuracy with ROC curve analysis underlying an area between 0.734 and 0.816. Ma2 autoantibodies in the blood from SI-NET patients were verified by western blot and sequential immunoprecipitation. Serum antibodies of patients stain Ma2 in the tumor tissue and neurons. We observed that SI-NET patients expressing Ma2 autoantibody levels below the cutoff had a longer progression and recurrence-free survival compared to those with higher titer. We also detected higher levels of Ma2 autoantibodies in blood samples from TLC and ALC patients than from healthy controls, as previously shown in small cell lung carcinoma samples. CONCLUSION: Here we show that high Ma2 autoantibody titer in the blood of SI-NET patients is a sensitive and specific biomarker, superior to chromogranin A (CgA for the risk of recurrence after radical operation of these tumors.

  2. Adult T-cell leukemia-associated antigen (ATLA): detection of a glycoprotein in cell- and virus-free supernatant.

    Science.gov (United States)

    Yamamoto, N; Schneider, J; Hinuma, Y; Hunsmann, G

    1982-01-01

    A glycoprotein of an apparent molecular mass of 46,000, gp 46, was enriched by affinity chromatography from the virus- and cell-free culture medium of adult T-cell leukemia virus (ATLV) infected cells. gp 46 was specifically precipitated with sera from patients with adult T-cell leukemia associated antigen (ATLA). Thus, gp 46 is a novel component of the ATLA antigen complex.

  3. Polypyridylruthenium(II complexes exert anti-schistosome activity and inhibit parasite acetylcholinesterases.

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    Madhu K Sundaraneedi

    2017-12-01

    Full Text Available Schistosomiasis affects over 200 million people and there are concerns whether the current chemotherapeutic control strategy (periodic mass drug administration with praziquantel (PZQ-the only licenced anti-schistosome compound is sustainable, necessitating the development of new drugs.We investigated the anti-schistosome efficacy of polypyridylruthenium(II complexes and showed they were active against all intra-mammalian stages of S. mansoni. Two compounds, Rubb12-tri and Rubb7-tnl, which were among the most potent in their ability to kill schistosomula and adult worms and inhibit egg hatching in vitro, were assessed for their efficacy in a mouse model of schistosomiasis using 5 consecutive daily i.v. doses of 2 mg/kg (Rubb12-tri and 10 mg/kg (Rubb7-tnl. Mice treated with Rubb12-tri showed an average 42% reduction (P = 0.009, over two independent trials, in adult worm burden. Liver egg burdens were not significantly decreased in either drug-treated group but ova from both of these groups showed significant decreases in hatching ability (Rubb12-tri-68%, Rubb7-tnl-56% and were significantly morphologically altered (Rubb12-tri-62% abnormal, Rubb7-tnl-35% abnormal. We hypothesize that the drugs exerted their activity, at least partially, through inhibition of both neuronal and tegumental acetylcholinesterases (AChEs, as worms treated in vitro showed significant decreases in activity of these enzymes. Further, treated parasites exhibited a significantly decreased ability to uptake glucose, significantly depleted glycogen stores and withered tubercules (a site of glycogen storage, implying drug-mediated interference in this nutrient acquisition pathway.Our data provide compelling evidence that ruthenium complexes are effective against all intra-mammalian stages of schistosomes, including schistosomula (refractory to PZQ and eggs (agents of disease transmissibility. Further, the results of this study suggest that schistosome AChE is a target of

  4. Enhanced protective efficacy of a chimeric form of the schistosomiasis vaccine antigen Sm-TSP-2.

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    Mark S Pearson

    Full Text Available The large extracellular loop of the Schistosoma mansoni tetraspanin, Sm-TSP-2, when fused to a thioredoxin partner and formulated with Freund's adjuvants, has been shown to be an efficacious vaccine against murine schistosomiasis. Moreover, Sm-TSP-2 is uniquely recognised by IgG(1 and IgG(3 from putatively resistant individuals resident in S. mansoni endemic areas in Brazil. In the present study, we expressed Sm-TSP-2 at high yield and in soluble form in E. coli without the need for a solubility enhancing fusion partner. We also expressed in E. coli a chimera called Sm-TSP-2/5B, which consisted of Sm-TSP-2 fused to the immunogenic 5B region of the hookworm aspartic protease and vaccine antigen, Na-APR-1. Sm-TSP-2 formulated with alum/CpG showed significant reductions in adult worm and liver egg burdens in two separate murine schistosomiasis challenge studies. Sm-TSP-2/5B afforded significantly greater protection than Sm-TSP-2 alone when both antigens were formulated with alum/CpG. The enhanced protection obtained with the chimeric fusion protein was associated with increased production of anti-Sm-TSP-2 antibodies and IL-4, IL-10 and IFN-γ from spleen cells of vaccinated animals. Sera from 666 individuals from Brazil who were infected with S. mansoni were screened for potentially deleterious IgE responses to Sm-TSP-2. Anti-Sm-TSP-2 IgE to this protein was not detected (also shown previously for Na-APR-1, suggesting that the chimeric antigen Sm-TSP-2/5B could be used to safely and effectively vaccinate people in areas where schistosomes and hookworms are endemic.

  5. Enhanced target-specific signal detection using an Escherichia coli lysate in multiplex microbead immunoassays with E. coli-derived recombinant antigens.

    Science.gov (United States)

    Crestani, Sandra; Leitolis, Amanda; Lima, Lucianna Freitas Oliveira; Krieger, Marco A; Foti, Leonardo

    2016-08-01

    Diverse techniques have been developed to analyze antibody-mediated responses to infections. However, the most common tests, i.e., enzyme-linked immunosorbent assays, require separate reactions for each antigen and consequently necessitate large sample volumes. Luminex technology allows the detection of multiple antibodies in a single experiment, but nonspecific binding can impair the results. Therefore, we examined the use of Escherichia coli lysates to reduce nonspecific binding and improve the results of liquid microarrays based on Luminex technology. Anti-bacteria antibodies were detected in human serum samples, as evidenced by high median fluorescence intensity (MFI) in assays performed with paramagnetic microspheres coupled with E. coli lysates. Moreover, the addition of an E. coli lysate as a blocker reduced the nonspecific binding of antigens produced by E. coli in a concentration-dependent manner. Tris-HCl reduced MFI values in negative samples, but did not affect MFI for positive samples. For microspheres coupled with different antigens, an E. coli lysate blocker significantly improved the fluorescence signals from positive samples. The addition of Tris-HCl and the E. coli lysate induced antigen-specific differences in MFI. This combination of the E. coli lysate blocker and Tris-HCl yielded a statistically significant improvement in MFI in the assays for Chagas disease and hepatitis C virus samples. However, for the Treponema pallidum p47 antigen improvement in MFI was only observed for the preparation with the E. coli blocker at a concentration of 3%. In conclusion, the addition of an E. coli lysate and Tris-HCl to the microarray assay reduced the nonspecific binding of human anti-bacteria antibodies and, therefore, increased the specific MFI. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. DIAGNOSTIC ROLE OF FLUORINE-18 (18F) FLUORODEOXYGLUCOSE POSITRON EMISSION TOMOGRAPHY COMPUTED TOMOGRAPHY IN DETECTING RECURRENT DISEASE IN PATIENTS WITH COLORECTAL CANCER AND ELEVATED CARCINOEMBRYONIC ANTIGEN.

    Science.gov (United States)

    Matovina, Emil; Mihailović, Jasna; Nikoletić, Katarina; Srbovan, Dolores

    2015-01-01

    Early detection of recurrence is an important factor for long term survival of patients with colorectal cancer. Measurement of serum levels of carcinoembryonic antigen has been commonly used in the postoperative surveillance of colorectal cancer. The purpose of this study was to evaluate the ability of positron emission tomography-computed tomography to detect pathological substrate of elevated serum carcinoembryonic antigen in patients with colorectal cancer. The patients with colorectal cancer who underwent curative surgical resection and/ or chemotherapy, who were found in our database, were analyzed retrospectively. Forty-eight 18F-fluorodeoxyglucose positron emission tomography-computed tomography studies including 45 patients (14 women, 31 men; mean age: 62.93 years) with elevated serum, carcinoembryonic antigen levels, which had been performed between January 2011 and January 2014, were evaluated. Serum levels of carcinoembryonic antigen were measured within 3 months after positron emission tomography-computed tomography examination. Final diagnosis of recurrence was made by histopathological findings, radiology studies or clinical follow-up. Recurrences were diagnosed in 37 patients, the prevalence being 77.1%. Liver metastases were found in 18 patients, abdominal, pelvic and/or mediastinal lymph nodes were positive in 19 patients, 11 patients had loco regional recurrences and 4 patients had pulmonary metastasis, and bone metastases were found in one patient. One patient was diagnosed with metastasis in scar tissue. The overall sensitivity and specificity of positron emission tomography-computed tomography was 90.24% and 71.42%, respectively. The positive and negative predictive values were 94.87% and 55.56%, respectively. 18F-fluorodeoxyglucose positron emission tomography-computed tomography is a powerful tool that could be used in determining colorectal cancer recurrence in patients with elevated carcinoembryonic antigen levels and could have an

  7. Detection of GAD-Ab index in diabetic patients using 35S labeled recombinant human GAD65 antigen

    International Nuclear Information System (INIS)

    Huang Gan; Zhao Zhiguang; Peng Jian; Yan Xiang; Zhu Xuping; Yang Lin; Li Xia; Wang Jianping; Jiang Tiejian

    2003-01-01

    Objective: To establish a novel method for measuring glutamic acid decarboxylase autoanti-bodies(GAD-Ab). Methods: Recombinant human GAD 65 was used as the antigen, in vitro transcribed and translated 35 S-GAD 65 as the tracer, a self-designed rotating incubation apparatus as the incubator, protein-A sepharose as the precipitator, and the liquid scintillation counter was used to measure radioactive count value to detect GAD-Ab. The positive cut-off point of GAD-Ab index was determined as > 0.05 by the 99.5% percentile in 109 healthy individuals. GAD-Ab levels were determined in 43 type 1 and 226 type 2 diabetic patients. Results: The optimized working conditions included SJ1515 35 S-methionine for in vitro transcription and translation, 20-30 r/min setup of rotating incubation apparatus, test temperature 4-25 degree C, freshly prepared buffer of pH 7.2-7.4, and horizontal rotor centrifuge. The new method was better than original one, with intra-assay CV of 4.9%-8.3% and inter-assay CV of 7.1%-10.8 %, specificity of 98.2%. The results were comparable with the figures issued by an international standardized laboratory (concordance was 98.3%, Kappa value 0.971). The positive rate of GAD-Ab was 58.1% (25 of 43) in type 1 and 10.2%(23 of 226) in type 2 diabetes patients, but only 1.8% (2 of 109) in healthy individuals. Conclusion: The new assay for GAD-Ab is a highly sensitive, accurate, specific and reproducible method for clinical use

  8. Trypanosomosis surveillance on Zanzibar island, using the trypanosomal antigen detection ELISA (enzyme-linked immunosorbent assay) technique

    Energy Technology Data Exchange (ETDEWEB)

    Mbwambo, H A [Animal Disease Research Inst. (ADRI), Dar-es-Salaam (Tanzania, United Republic of)

    1997-02-01

    The effectiveness of trypanosomosis control programs depends greatly on prior knowledge of basic data of the epidemiological situation of the disease, which in turns depends, among others, on the use of techniques that give a fairly quick and accurate diagnosis. An antigen-detection (Ag) ELISA was first introduced into Tanzania and validated at the Animal Disease Research Institute (ADRI) through the FAO/IAEA Research Contract (RC) No. 5030/NL. Incorporation of the Ag-ELISA technique into a FAO animal disease control project (1986-1993) on Unguja island, in 1992, revealed useful information of high trypanosomosis prevalence in an area previously declared free of the disease using just stained blood smears and buffy coat examinations. This triggered further efforts into more intensive surveys of the tsetse and trypanosomosis situation on Unguja island. The present study is a continuation of previous work in an effort to confirm the practical application of Ag-ELISA in trypanosomosis control operations. Results obtained from a known tsetse and trypanosomosis-free area, on Pemba island, showed a high specificity of the test for Trypanosoma congolense, T. vivax and T. brucei. A preliminary cut-off value of 10% (Percent Positivity = PP) was used. When the PP of 10 was used on sera of trypanosomosis-endemic areas (Mangapwani, Ndijani, Dunga and Kikungwi) on Unguja island, the results reflected the `real` trypanosomis situation in the affected area. This was most strongly felt in the Mangapwani area, where tsetse and trypanosomosis were considered under control by 1994 (no tsetse flies were caught and no samples were encountered positive by the buffy coat technique). However, it should be stressed that the buffy coat technique and the Ag-ELISA complement each other and should be used in conjunction. (author). 8 refs, 1 fig., 5 tabs.

  9. Trypanosomosis surveillance on Zanzibar island, using the trypanosomal antigen detection ELISA (enzyme-linked immunosorbent assay) technique

    International Nuclear Information System (INIS)

    Mbwambo, H.A.

    1997-01-01

    The effectiveness of trypanosomosis control programs depends greatly on prior knowledge of basic data of the epidemiological situation of the disease, which in turns depends, among others, on the use of techniques that give a fairly quick and accurate diagnosis. An antigen-detection (Ag) ELISA was first introduced into Tanzania and validated at the Animal Disease Research Institute (ADRI) through the FAO/IAEA Research Contract (RC) No. 5030/NL. Incorporation of the Ag-ELISA technique into a FAO animal disease control project (1986-1993) on Unguja island, in 1992, revealed useful information of high trypanosomosis prevalence in an area previously declared free of the disease using just stained blood smears and buffy coat examinations. This triggered further efforts into more intensive surveys of the tsetse and trypanosomosis situation on Unguja island. The present study is a continuation of previous work in an effort to confirm the practical application of Ag-ELISA in trypanosomosis control operations. Results obtained from a known tsetse and trypanosomosis-free area, on Pemba island, showed a high specificity of the test for Trypanosoma congolense, T. vivax and T. brucei. A preliminary cut-off value of 10% (Percent Positivity = PP) was used. When the PP of 10 was used on sera of trypanosomosis-endemic areas (Mangapwani, Ndijani, Dunga and Kikungwi) on Unguja island, the results reflected the 'real' trypanosomis situation in the affected area. This was most strongly felt in the Mangapwani area, where tsetse and trypanosomosis were considered under control by 1994 (no tsetse flies were caught and no samples were encountered positive by the buffy coat technique). However, it should be stressed that the buffy coat technique and the Ag-ELISA complement each other and should be used in conjunction. (author). 8 refs, 1 fig., 5 tabs

  10. Evaluation of the antibody-detection ELISA using plates precoated with denatured T. congolense and T. vivax antigens for monitoring tsetse and trypanosomosis control in Zambia

    International Nuclear Information System (INIS)

    Machila, N.; Sinyangwe, L.; Eisler, M.C.

    2000-01-01

    An evaluation of the indirect enzyme-linked immunosorbent assay (ELISA) for the detection of anti-trypanosomal antibodies in bovine serum was conducted using ELISA plates pre-coated with denatured T. congolense and T. vivax antigen. The study was conducted on 280 samples from a parasitologically positive cattle population and 200 samples from a negative cattle population. The overwhelming majority of trypanosome infections in the parasitologically positive cattle were T. congolense. The Ab-ELISA was able to discriminate between the negative and positive cattle populations, at an optimum cut-off point of 40% positivity (T. congolense antigen), with 89% sensitivity and 86% specificity; and for the T. vivax antigen, the optimum cut-off point was at 30%, with 81% sensitivity and 70% specificity. However, the optical densities (OD) and percentage positivity (PP) values for sera from both the reference positive and negative cattle populations were unacceptably high particularly in the ELISA using T. congolense antigen. Furthermore the quality control sera used in the assay appear to have inappropriately low OD and PP values by comparison to typical sera from the reference positive and negative cattle populations. It is suggested that these ELISA's be re-titrated using more appropriate quality assurance sera. This should result in OD and PP values for sera from the reference populations failing within acceptable ranges. (author)

  11. Diagnostic accuracy of tests to detect hepatitis B surface antigen: a systematic review of the literature and meta-analysis

    Directory of Open Access Journals (Sweden)

    Ali Amini

    2017-11-01

    Full Text Available Abstract Background Chronic Hepatitis B Virus (HBV infection is characterised by the persistence of hepatitis B surface antigen (HBsAg. Expanding HBV diagnosis and treatment programmes into low resource settings will require high quality but inexpensive rapid diagnostic tests (RDTs in addition to laboratory-based enzyme immunoassays (EIAs to detect HBsAg. The purpose of this review is to assess the clinical accuracy of available diagnostic tests to detect HBsAg to inform recommendations on testing strategies in 2017 WHO hepatitis testing guidelines. Methods The systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA guidelines using 9 databases. Two reviewers independently extracted data according to a pre-specified plan and evaluated study quality. Meta-analysis was performed. HBsAg diagnostic accuracy of rapid diagnostic tests (RDTs was compared to enzyme immunoassay (EIA and nucleic-acid test (NAT reference standards. Subanalyses were performed to determine accuracy among brands, HIV-status and specimen type. Results Of the 40 studies that met the inclusion criteria, 33 compared RDTs and/or EIAs against EIAs and 7 against NATs as reference standards. Thirty studies assessed diagnostic accuracy of 33 brands of RDTs in 23,716 individuals from 23 countries using EIA as the reference standard. The pooled sensitivity and specificity were 90.0% (95% CI: 89.1, 90.8 and 99.5% (95% CI: 99.4, 99.5 respectively, but accuracy varied widely among brands. Accuracy did not differ significantly whether serum, plasma, venous or capillary whole blood was used. Pooled sensitivity of RDTs in 5 studies of HIV-positive persons was lower at 72.3% (95% CI: 67.9, 76.4 compared to that in HIV-negative persons, but specificity remained high. Five studies evaluated 8 EIAs against a chemiluminescence immunoassay reference standard with a pooled sensitivity and specificity of 88.9% (95% CI: 87.0, 90.6 and

  12. Immunohistochemical detection and correlation between MHC antigen and cell-mediated immune system in recurrent glioma by APAAP method.

    Science.gov (United States)

    Miyagi, K; Ingram, M; Techy, G B; Jacques, D B; Freshwater, D B; Sheldon, H

    1990-09-01

    As part of an on-going clinical trial of immunotherapy for recurrent malignant gliomas, using alkaline phosphatase-anti-alkaline phosphatase method with monoclonal antibodies, we investigated the correlation between expression of the major histocompatibility complex (MHC) and the subpopulation of tumor-infiltrating lymphocytes (TILs) in 38 glioma specimens (20 grade IV, 11 grade III, and 7 grade II) from 33 patients. Thirty specimens (78.9%) were positive to class I MHC antigen and 20 (52.6%) were positive to class II MHC antigen. The correlations between class I MHC antigen expression and the number of infiltrating T8 (p less than 0.01), and also between class II MHC antigen expression and the number of infiltrating T4 (p less than 0.05) were significant. We conclude that TILs are the result of immunoreaction (host-defense mechanism). 31.6% of specimens had perivascular infiltration of T cells. The main infiltrating lymphocyte subset in moderate to marked perivascular cuffing was T4. Our results may indicate that lack of MHC antigen on the glioma cell surface has a share in the poor immunogenicity in glioma-bearing patients. In addition, considering the effector/target ratio, the number of infiltrating lymphocytes against glioma cells was too small, so the immunological intervention seems to be essential in glioma therapy. Previous radiation therapy and chemotherapy, including steroid therapy, did not influence lymphocyte and macrophage infiltration.

  13. Proteomic analysis of human skin treated with larval schistosome peptidases reveals distinct invasion strategies among species of blood flukes.

    Directory of Open Access Journals (Sweden)

    Jessica Ingram

    2011-09-01

    Full Text Available Skin invasion is the initial step in infection of the human host by schistosome blood flukes. Schistosome larvae have the remarkable ability to overcome the physical and biochemical barriers present in skin in the absence of any mechanical trauma. While a serine peptidase with activity against insoluble elastin appears to be essential for this process in one species of schistosomes, Schistosoma mansoni, it is unknown whether other schistosome species use the same peptidase to facilitate entry into their hosts.Recent genome sequencing projects, together with a number of biochemical studies, identified alternative peptidases that Schistosoma japonicum or Trichobilharzia regenti could use to facilitate migration through skin. In this study, we used comparative proteomic analysis of human skin treated with purified cercarial elastase, the known invasive peptidase of S. mansoni, or S. mansoni cathespin B2, a close homolog of the putative invasive peptidase of S. japonicum, to identify substrates of either peptidase. Select skin proteins were then confirmed as substrates by in vitro digestion assays.This study demonstrates that an S. mansoni ortholog of the candidate invasive peptidase of S. japonicum and T. regenti, cathepsin B2, is capable of efficiently cleaving many of the same host skin substrates as the invasive serine peptidase of S. mansoni, cercarial elastase. At the same time, identification of unique substrates and the broader species specificity of cathepsin B2 suggest that the cercarial elastase gene family amplified as an adaptation of schistosomes to human hosts.

  14. Morphology and surface topography of the schistosome Bivitellobilharzia nairi from the Asian elephant (Elephas maximus maximus) in Sri Lanka.

    Science.gov (United States)

    Rajapakse, R P V J; Iwagami, M; Wickramasinghe, S; Walker, S M; Agatsuma, T

    2013-09-01

    Bivitellobilharzia nairi was first recorded from an Indian elephant (Elephas maximus) in Berlin. Infections with this parasite have become increasingly important in E. maximus maximus populations in Sri Lanka. The present work is the first morphological description of this schistosome from Sri Lanka. A number of adult worms were recovered from a dead Asian elephant near the elephant orphanage, Pinnawala, in Sri Lanka. The observed clinical features of the infected elephant included emaciation, subventral oedema and anaemia. Post-mortem results indicated that the liver was enlarged and adult schistosomes were found in the blood vessels of the liver parenchyma. The total number of worms recovered from a portion of the liver was 129,870, which is an average of 22 worms per 100 g of liver. The present study uses both light microscopic and scanning electron microscope (SEM) techniques for the morphological and topographical characterization of this parasite and to permit comparison with other species of schistosomes. Morphologically, these worms correspond very well to the description of B. nairi by Dutt & Srivastava (1955). Moreover, it is clear that B. nairi is a distinctive species easily differentiated from other schistosomes. The SEM study of the tegument of male worms shows that the surface of B. nairi is smoother than in other schistosomes.

  15. Development and evaluation of a truncated recombinant NS3 antigen-based indirect ELISA for detection of pestivirus antibodies in sheep and goats.

    Science.gov (United States)

    Kalaiyarasu, Semmannan; Mishra, Niranjan; Rajukumar, Katherukamem; Nema, Ram Kumar; Behera, Sthita Pragnya

    2015-01-01

    The aim of this study was to develop an indirect ELISA using the helicase domain of bovine viral diarrhoea virus (BVDV) NS3 protein instead of full-length NS3 protein for detection of BVDV and BDV antibodies in sheep and goats and its validation by comparing its sensitivity and specificity with virus neutralization test (VNT) as the reference test. The purified 50 kDa recombinant NS3 protein was used as the coating antigen in the ELISA. The optimal concentration of antigen was 320 ng/well at a serum dilution of 1:20 and the optimal positive cut-off optical density value was 0.40 based on test results of 418 VNT negative sheep and goat sera samples. When 569 serum samples from sheep (463) and goats (106) were tested, the ELISA showed a sensitivity of 91.71% and specificity of 94.59% with BVDV VNT. A good correlation (93.67%) was observed between the two tests. It showed a sensitivity of 85% and specificity of 86.6% with VNT in detecting BDV antibody positive or negative samples. This study demonstrates the efficacy of truncated recombinant NS3 antigen based ELISA for seroepidemiological study of pestivirus infection in sheep and goats.

  16. Clinical score and rapid antigen detection test to guide antibiotic use for sore throats: randomised controlled trial of PRISM (primary care streptococcal management).

    Science.gov (United States)

    Little, Paul; Hobbs, F D Richard; Moore, Michael; Mant, David; Williamson, Ian; McNulty, Cliodna; Cheng, Ying Edith; Leydon, Geraldine; McManus, Richard; Kelly, Joanne; Barnett, Jane; Glasziou, Paul; Mullee, Mark

    2013-10-10

    To determine the effect of clinical scores that predict streptococcal infection or rapid streptococcal antigen detection tests compared with delayed antibiotic prescribing. Open adaptive pragmatic parallel group randomised controlled trial. Primary care in United Kingdom. Patients aged ≥ 3 with acute sore throat. An internet programme randomised patients to targeted antibiotic use according to: delayed antibiotics (the comparator group for analyses), clinical score, or antigen test used according to clinical score. During the trial a preliminary streptococcal score (score 1, n=1129) was replaced by a more consistent score (score 2, n=631; features: fever during previous 24 hours; purulence; attends rapidly (within three days after onset of symptoms); inflamed tonsils; no cough/coryza (acronym FeverPAIN). Symptom severity reported by patients on a 7 point Likert scale (mean severity of sore throat/difficulty swallowing for days two to four after the consultation (primary outcome)), duration of symptoms, use of antibiotics. For score 1 there were no significant differences between groups. For score 2, symptom severity was documented in 80% (168/207 (81%) in delayed antibiotics group; 168/211 (80%) in clinical score group; 166/213 (78%) in antigen test group). Reported severity of symptoms was lower in the clinical score group (-0.33, 95% confidence interval -0.64 to -0.02; P=0.04), equivalent to one in three rating sore throat a slight versus moderate problem, with a similar reduction for the antigen test group (-0.30, -0.61 to -0.00; P=0.05). Symptoms rated moderately bad or worse resolved significantly faster in the clinical score group (hazard ratio 1.30, 95% confidence interval 1.03 to 1.63) but not the antigen test group (1.11, 0.88 to 1.40). In the delayed antibiotics group, 75/164 (46%) used antibiotics. Use of antibiotics in the clinical score group (60/161) was 29% lower (adjusted risk ratio 0.71, 95% confidence interval 0.50 to 0.95; P=0.02) and in the

  17. DNA barcoding of schistosome cercariae reveals a novel sub-lineage within Schistosoma rodhaini from Ngamba Island Chimpanzee Sanctuary, Lake Victoria.

    Science.gov (United States)

    Standley, C J; Stothard, J R

    2012-10-01

    While Schistosoma rodhaini is typically considered a parasite of small mammals and is very scantly distributed in the Lake Victoria basin, it is known to hybridize with the more widespread Schistosoma mansoni, the causative agent of intestinal schistosomiasis. As part of broader parasitological and malacological surveys for S. mansoni across Lake Victoria, schistosome cercariae were harvested from a field-caught Biomphalaria choanomphala taken on Ngamba Island Chimpanzee Sanctuary, Uganda. Upon DNA barcoding, these cercariae were found to be a mixture of both S. rodhaini and S. mansoni, with further phylogenetic analysis revealing a hitherto unknown sub-lineage within S. rodhaini. Despite repeated sampling for eggs and miracidia from both chimpanzees and staff on Ngamba Island Sanctuary, detection of S. rodhaini within local definitive hosts awaits additional efforts, which should be mindful of a potential host role of spotted-necked otters.

  18. Detection of anti-dsDNA by IgG ELISA test using two different sources of antigens: calf thymus versus E.coli

    Directory of Open Access Journals (Sweden)

    Mohammadi M

    2009-04-01

    Full Text Available "nBackground: Anti-dsDNA antibodies frequently found in the sera Systemic Lupus Erythematosus patients, particularly in active disease stage. Nowadays exploit different eukaryotic and prokaryotic dsDNA as antigen source and different reagents as binder. The aim of this study to compared two dsDNA different sources and tow different kinds of reagents for binder in ELISA test. "nMethods: In this study bacterial genomic DNA from E.coli (ATCC 25922 and genomic DNA from calf thymus extracted with high purity and were used as antigens for IgG anti-dsDNA detection by ELISA. To coat dsDNA in microtiter wells, tow different kinds of reagents including methylated -BSA and poly-l-lysine (for pre-coating are used. Sera from systemic lupus erythematosus patients and from normal blood donors are used to assess sensitivity and specificity of our ELISA test in compared with IF test and commercial kits. "nResults: Our results displayed pre-coating of microtiter plates with methylated -BSA reduce nonspecific binding reaction and the relative sensitivity and specificity of ELISA increased when calf thymus DNA is employed as antigenic source in compared with IF test and commercial kits 80%, 88% and 100%, 98% respectively, but when E.coli DNA is used 73%, 69% and 85%, 79%, respectively. "nConclusion: The genomic DNA from calf thymus is a potentially useful source of antigen for detection of anti-dsDNA by ELISA. Also the use of methylatted- BSA could have an effective role in reducing of nonspecific binding reactions.

  19. The Use of Fluoroproline in MUC1 Antigen Enables Efficient Detection of Antibodies in Patients with Prostate Cancer

    NARCIS (Netherlands)

    Somovilla, Víctor J; Bermejo, Iris A.; Albuquerque, Inês S; Martínez-Sáez, Nuria; Castro-López, Jorge; García-Martín, Fayna; Compañón, Ismael; Hinou, Hiroshi; Nishimura, Shin-Ichiro; Jiménez-Barbero, Jesús; Asensio, Juan L.; Avenoza, Alberto; Busto, Jesús H.; Hurtado-Guerrero, Ramón; Peregrina, Jesús M.; Bernardes, Gonçalo J L; Corzana, Francisco

    2017-01-01

    A structure-based design of a new generation of tumor-associated glycopeptides with improved affinity against two anti-MUC1 antibodies is described. These unique antigens feature a fluorinated proline residue, such as a (4S)-4-fluoro-l-proline or 4,4-difluoro-l-proline, at the most immunogenic

  20. Detection of Immune-Complex Dissociated Nonstructural-1 (NS-1) Antigen in Patients with Acute Dengue Virus Infections

    NARCIS (Netherlands)

    P. Koraka (Penelope); C.P. Burghoorn-Maas; A. Falconar; T.E. Setiati (Tatty); K. Djamiatun; J. Groen (Jan); A.D.M.E. Osterhaus (Albert)

    2003-01-01

    textabstractAccurate and timely diagnosis of dengue virus (DEN) infections is essential for the differential diagnosis of patients with febrile illness and hemorrhagic fever. In the present study, the diagnostic value of a newly developed immune-complex dissociated nonstructural-1 (NS-1) antigen dot

  1. Development of a T7 Phage Display Library to Detect Sarcoidosis and Tuberculosis by a Panel of Novel Antigens

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    Harvinder Talwar

    2015-04-01

    Full Text Available Sarcoidosis is a granulomatous inflammatory disease, diagnosed through tissue biopsy of involved organs in the absence of other causes such as tuberculosis (TB. No specific serologic test is available to diagnose and differentiate sarcoidosis from TB. Using a high throughput method, we developed a T7 phage display cDNA library derived from mRNA isolated from bronchoalveolar lavage (BAL cells and leukocytes of sarcoidosis patients. This complex cDNA library was biopanned to obtain 1152 potential sarcoidosis antigens and a microarray was constructed to immunoscreen two different sets of sera from healthy controls and sarcoidosis. Meta-analysis identified 259 discriminating sarcoidosis antigens, and multivariate analysis identified 32 antigens with a sensitivity of 89% and a specificity of 83% to classify sarcoidosis from healthy controls. Additionally, interrogating the same microarray platform with sera from subjects with TB, we identified 50 clones that distinguish between TB, sarcoidosis and healthy controls. The top 10 sarcoidosis and TB specific clones were sequenced and homologies were searched in the public database revealing unique epitopes and mimotopes in each group. Here, we show for the first time that immunoscreenings of a library derived from sarcoidosis tissue differentiates between sarcoidosis and tuberculosis antigens. These novel biomarkers can improve diagnosis of sarcoidosis and TB, and may aid to develop or evaluate a TB vaccine.

  2. Standardization of micro-enzyme-linked immunosorbent assay (ELISA) and Western blot for detection of Trypanosoma cruzi antibodies using extracts from Mexican strains as antigens.

    Science.gov (United States)

    Sánchez, B; Monteón, V; Reyes, P A; Espinoza, B

    2001-01-01

    This report describes two assays for the detection of anti-Trypanosoma cruzi antibodies using Mexican strains of the parasite and the concordance with two assays previously evaluated at the Instituto Nacional de Cardiología Ignacio Chávez in Mexico City. Micro-enzyme-linked immunosorbent assay (ELISA) and Western blot were used for the detection of T. cruzi antibodies with a total extract of epimastigote from Ninoa and Queretaro, which are Mexican strains of T. cruzi. To standardize these methods, a total of 246 serum samples was used. In addition, sera from six confirmed Mexican chronic individuals in the asymptomatic phase were also used for comparison with the Argentinean antigen. ELISA was 100% specific in that no false positive results were found with sera of both healthy individuals and non-Chagasic cardiopaths. Sera from individuals infected with Leishmania sp. showed approximately 16% of cross-reaction with ELISA. The test showed a positive predictive value of 90% and a negative predictive value of 100%. Western blot was also a highly sensitive test for detecting chronic Chagasic symptomatic patients from Mexico because no false negative results were obtained. Furthermore, it was possible to use Western blot to detect seven immunodominant antigens of approximately 30, 32, 40, 42, 65, 70, and 83 kDa. Concordance with two previous standardized tests at the Instituto Nacional de Cardiología showed a Kappa index of 0.96, indicating high concordance between the results obtained at these two laboratories. Finally, ELISA using Ninoa antigen extract was more sensitive than ELISA with an Argentinean extract, which failed to detect individuals in the chronic asymptomatic phase (undetermined phase) of infection. This study indicates that ELISA and Western blot using Ninoa and/or Queretaro extracts of T. cruzi as antigens are useful tools in the detection of individuals who have been exposed to T. cruzi both in the undetermined/asymptomatic and symptomatic phases

  3. Isocyanate test antigens

    International Nuclear Information System (INIS)

    Karol, M.H.; Alarie, Y.C.

    1980-01-01

    A test antigen for detecting antibodies to a diisocyanate comprises the reaction product of a protein and a monoisocyanate derived from the same radical as the diisocyanate. The diisocyanates most usually encountered and therefore calling for antibody detection are those of toluene, hexamethylene, methylene, isophorone and naphthylene. The preferred protein is human serum albumin. (author)

  4. Clinical outcomes of prostate cancer patients in Yokosuka City, Japan: A comparative study between cases detected by prostate-specific antigen-based screening in Yokosuka and those detected by other means.

    Science.gov (United States)

    Sakai, Naoki; Taguri, Masataka; Kobayashi, Kazuki; Noguchi, Sumio; Ikeda, Shigeru; Koh, Hideshige; Satomi, Yoshiaki; Furuhata, Akihiko

    2015-08-01

    To investigate whether prostate-specific antigen-based screening reduced the prostate cancer mortality rate in Yokosuka, Japan. We carried out a cohort study, in which we compared clinical outcomes between patients detected by prostate-specific antigen-based screening (S group n = 524) versus those detected by other means (NS group n = 1044). Clinical and pathological factors were evaluated using Cox regression analyses and the Kaplan-Meier method. A total of 1.5% (8/524) of patients in the S group and 6.7% (70/1044) of those in the NS group died from prostate cancer during follow up. A total of 8.0% (42/524) of patients in the S group and 11.4% (119/1044) in the NS group died from other causes. The 10-year cancer specific survival rates of the S and NS groups were 97% and 86%, respectively (P prostate-specific antigen 100 ng/mL or more was significantly lower in the S group than the NS group: 7.8% and 23.0%, respectively (P specific survival (hazard ratio 4.808, 95% confidence interval 1.044-22.14, P = 0.044). Prostate-specific antigen-based population screening in Yokosuka City might help to reduce the prostate cancer mortality rate. © 2015 The Japanese Urological Association.

  5. Detection of prostate specific antigen (PSA) in human saliva using an ultra-sensitive nanocomposite of graphene nanoplatelets with diblock-co-polymers and Au electrodes.

    Science.gov (United States)

    Khan, M S; Dighe, K; Wang, Z; Srivastava, I; Daza, E; Schwartz-Dual, A S; Ghannam, J; Misra, S K; Pan, D

    2018-02-26

    Prostate-specific antigen (PSA) is a commonly used biomarker for the detection of prostate cancer (PCa) and there are numerous data available for its invasive detection in the serum and whole blood. In this work, an electrochemical sensing method was devised to detect traces of PSA in human saliva using a hybrid nanocomposite of graphene nanoplatelets with diblock co-polymers and Au electrodes (GRP-PS 67 -b-PAA 27 -Au). The pure graphitic composition on filter paper provides significantly high electrical and thermal conductivity while PS 67 -b-PAA 27 makes an amphiphilic bridge between GRP units. The sensor utilizes the binding of an anti-PSA antibody with an antigen-PSA to act as a resistor in a circuit providing an impedance change that in turn allows for the detection and quantification of PSA in saliva samples. A miniaturized electrical impedance analyzer was interfaced with a sensor chip and the data were recorded in real-time using a Bluetooth-enabled module. This fully integrated and optimized sensing device exhibited a wide PSA range of detection from 0.1 pg mL -1 to 100 ng mL -1 (R 2 = 0.963) with a lower limit of detection of 40 fg mL -1 . The performance of the biosensor chip was validated with an enzyme-linked immunosorbent assay technique with a regression coefficient as high as 0.940. The advantages of the newly developed saliva-PSA electrical biosensor over previously reported serum-PSA electrochemical biosensors include a faster response time (3-5 min) to achieve a stable electrical signal for PSA detection, high selectivity, improved sensitivity, no additional requirement of a redox electrolyte for electron exchange and excellent shelf life. The presented sensor is aimed for clinical commercialization to detect PSA in human saliva.

  6. Inaccuracy of Enzyme-Linked Immunosorbent Assay Using Soluble and Recombinant Antigens to Detect Asymptomatic Infection by Leishmania infantum

    Science.gov (United States)

    Moreno, Elizabeth Castro; Gonçalves, Andréa Vieira; Chaves, Anderson Vieira; Melo, Maria Norma; Lambertucci, José Roberto; Andrade, Antero Silva Ribeiro; Negrão-Corrêa, Deborah; Antunes, Carlos Mauricio de Figueiredo; Carneiro, Mariângela

    2009-01-01

    Background One of the most important drawbacks in visceral leishmaniasis (VL) population studies is the difficulty of diagnosing asymptomatic carriers. The aim of this study, conducted in an urban area in the Southeast of Brazil, was to evaluate the performance of serology to identify asymptomatic VL infection in participants selected from a cohort with a two-year follow-up period. Methodology Blood samples were collected in 2001 from 136 cohort participants (97 positive and 39 negatives, PCR/hybridization carried out in 1999). They were clinically evaluated and none had progressed to disease from their asymptomatic state. As controls, blood samples from 22 control individuals and 8 patients with kala-azar were collected. Two molecular biology techniques (reference tests) were performed: PCR with Leishmania-generic primer followed by hybridization using L. infantum probe, and PCR with specific primer to L. donovani complex. Plasma samples were tested by ELISA using three different antigens: L. infantum and L. amazonensis crude antigens, and rK39 recombinant protein. Accuracy of the serological tests was evaluated using sensitivity, specificity, likelihood ratio and ROC curve. Findings The presence of Leishmania was confirmed, by molecular techniques, in all kala-azar patients and in 117 (86%) of the 136 cohort participants. Kala-azar patients showed high reactivity in ELISAs, whereas asymptomatic individuals presented low reactivity against the antigens tested. When compared to molecular techniques, the L. amazonensis and L. infantum antigens showed higher sensitivity (49.6% and 41.0%, respectively) than rK39 (26.5%); however, the specificity of rK39 was higher (73.7%) than L. amazonensis (52.6%) and L. infantum antigens (36.8%). Moreover, there was low agreement among the different antigens used (kappa<0.10). Conclusions Serological tests were inaccurate for diagnosing asymptomatic infections compared to molecular methods; this could lead to misclassification bias

  7. 68Ga-PSMA PET/CT in Patients with Rising Prostatic-Specific Antigen After Definitive Treatment of Prostate Cancer: Detection Efficacy and Diagnostic accuracy.

    Science.gov (United States)

    Hamed, Maged Abdel Galil; Basha, Mohammad Abd Alkhalik; Ahmed, Hussien; Obaya, Ahmed Ali; Afifi, Amira Hamed Mohamed; Abdelbary, Eman H

    2018-06-20

    68 Ga-prostate-specific membrane antigen-11 ( 68 Ga-PSMA-11) is a recently developed positron emission tomography (PET) tracer that can detect prostate cancer (PC) relapses and metastases with high contrast resolution. The aim of this study was to assess the detection efficacy and diagnostic accuracy of 68 Ga-PSMA PET/CT image in patients with rising prostatic-specific antigen (PSA) after treatment of PC. The present prospective study included 188 patients who exhibited rising of PSA level on a routine follow-up examination after definitive treatment of PC. All patients underwent a 68 Ga-PSMA PET/CT examination. For each patient, we determined the disease stage, the Gleason score, and the maximum standardized uptake value of the local recurrence and extraprostatic metastases. The detection efficacy and diagnostic accuracy of 68 Ga-PSMA PET/CT were established by histopathology and clinical and imaging follow-up as the reference standards. 68 Ga-PSMA PET/CT detected tumour relapse in 165 patients (35 patients had local recurrence, 106 patients had extraprostatic metastases, and 24 patients had combined lesions). The sensitivity, specificity, and accuracy values of 68 Ga-PSMA PET/CT examination in the detection of PC recurrence were 98.8%, 100%, and 98.8%, respectively. 68 Ga-PSMA PET/CT revealed an overall detection rate of 87.8% (165/188) in patients with rising PSA (median of 2.2 ng/mL, and range of 0.01-70 ng/mL). 68 Ga-PSMA PET/CT is a valuable tool for the detection of PC local recurrence or extraprostatic metastases following rising PSA levels after primary definitive therapy and should be incorporated during routine work-up. Copyright © 2018. Published by Elsevier Inc.

  8. The detection of K88, K99 fimbrial antigen and enterotoxin genes of Escherichia coli isolated from piglets and calves with diarrhoea in Indonesia

    Directory of Open Access Journals (Sweden)

    Supar

    1996-03-01

    Full Text Available Enterotoxigenic Escherichia coli (ETEC strains cause diarrhoeal disease in piglets and calves in Indonesia. These strains possess two virulence factors namely attachment and enterotoxin antigens . These factors could be detected phenotypically and genetically. Haemolytic Escherichia coli (E coli isolates possessing K88 fimbrial antigen associated with 0-group 108 and 149. They were positive for K88 gene and demonstrated their ability to produce heat labile enterotoxin (LT and genetically were all positive for LT gene . Seventeen isolates ofE coli K88 which associated with 0-group 149 were positive forSTb gene, other O-serotypes were negative . Ten isolates of Ecoli K88 which associated with 0-group 108 possessed K88, K99, LT and STa genes, but negative for STb gene . However, phenotypically the K99 antigen and STa toxin were not expressed under laboratory conditions, the reason was not well understood . E. coli K99 strains isolated from calves wit h diarrhoea were all associated with 0-group 9 and produced STa toxin when tested by suckling mousse bioassay. The E. coli K99 calf isolates were all hybridized with K99 and STa gene only . It is likely that K99 gene is associated with STa gene . The DNA hybridization technique is more convenience to be used for confirmation diagnosis of colibacillosis, however, not all veterinary laboratories could perform these tests .

  9. Automation of the ELISpot assay for high-throughput detection of antigen-specific T-cell responses.

    Science.gov (United States)

    Almeida, Coral-Ann M; Roberts, Steven G; Laird, Rebecca; McKinnon, Elizabeth; Ahmed, Imran; Pfafferott, Katja; Turley, Joanne; Keane, Niamh M; Lucas, Andrew; Rushton, Ben; Chopra, Abha; Mallal, Simon; John, Mina

    2009-05-15

    The enzyme linked immunospot (ELISpot) assay is a fundamental tool in cellular immunology, providing both quantitative and qualitative information on cellular cytokine responses to defined antigens. It enables the comprehensive screening of patient derived peripheral blood mononuclear cells to reveal the antigenic restriction of T-cell responses and is an emerging technique in clinical laboratory investigation of certain infectious diseases. As with all cellular-based assays, the final results of the assay are dependent on a number of technical variables that may impact precision if not highly standardised between operators. When studies that are large scale or using multiple antigens are set up manually, these assays may be labour intensive, have many manual handling steps, are subject to data and sample integrity failure and may show large inter-operator variability. Here we describe the successful automated performance of the interferon (IFN)-gamma ELISpot assay from cell counting through to electronic capture of cytokine quantitation and present the results of a comparison between automated and manual performance of the ELISpot assay. The mean number of spot forming units enumerated by both methods for limiting dilutions of CMV, EBV and influenza (CEF)-derived peptides in six healthy individuals were highly correlated (r>0.83, pautomated system compared favourably with the manual ELISpot and further ensured electronic tracking, increased through-put and reduced turnaround time.

  10. Immunodiagnosis of paracoccidioidomycosis due to Paracoccidioides brasiliensis using a latex test: detection of specific antibody anti-gp43 and specific antigen gp43.

    Directory of Open Access Journals (Sweden)

    Priscila Oliveira Dos Santos

    2015-02-01

    Full Text Available Paracoccidioidomycosis (PCM is a life-threatening systemic disease and is a neglected public health problem in many endemic regions of Latin America. Though several diagnostic methods are available, almost all of them present with some limitations.A latex immunoassay using sensitized latex particles (SLPs with gp43 antigen, the immunodominant antigen of Paracoccidioides brasiliensis, or the monoclonal antibody mAb17c (anti-gp43 was evaluated for antibody or antigen detection in sera, cerebrospinal fluid (CSF, and bronchoalveolar lavage (BAL from patients with PCM due to P. brasiliensis. The gp43-SLPs performed optimally to detect specific antibodies with high levels of sensitivity (98.46%, 95% CI 91.7-100.0, specificity (93.94%, 95% CI 87.3-97.7, and positive (91.4% and negative (98.9% predictive values. In addition, we propose the use of mAb17c-SLPs to detect circulating gp43, which would be particularly important in patients with immune deficiencies who fail to produce normal levels of immunoglobulins, achieving good levels of sensitivity (96.92%, 95% CI 89.3-99.6, specificity (88.89%, 95% CI 81.0-94.3, and positive (85.1% and negative (97.8% predictive values. Very good agreement between latex tests and double immune diffusion was observed for gp43-SLPs (k = 0.924 and mAb17c-SLPs (k = 0.850, which reinforces the usefulness of our tests for the rapid diagnosis of PCM in less than 10 minutes. Minor cross-reactivity occurred with sera from patients with other fungal infections. We successfully detected antigens and antibodies from CSF and BAL samples. In addition, the latex test was useful for monitoring PCM patients receiving therapy.The high diagnostic accuracy, low cost, reduced assay time, and simplicity of this new latex test offer the potential to be commercialized and makes it an attractive diagnostic assay for use not only in clinics and medical mycology laboratories, but mainly in remote locations with limited laboratory infrastructure

  11. Mobile Diagnostics Based on Motion? A Close Look at Motility Patterns in the Schistosome Life Cycle

    Directory of Open Access Journals (Sweden)

    Ewert Linder

    2016-06-01

    Full Text Available Imaging at high resolution and subsequent image analysis with modified mobile phones have the potential to solve problems related to microscopy-based diagnostics of parasitic infections in many endemic regions. Diagnostics using the computing power of “smartphones” is not restricted by limited expertise or limitations set by visual perception of a microscopist. Thus diagnostics currently almost exclusively dependent on recognition of morphological features of pathogenic organisms could be based on additional properties, such as motility characteristics recognizable by computer vision. Of special interest are infectious larval stages and “micro swimmers” of e.g., the schistosome life cycle, which infect the intermediate and definitive hosts, respectively. The ciliated miracidium, emerges from the excreted egg upon its contact with water. This means that for diagnostics, recognition of a swimming miracidium is equivalent to recognition of an egg. The motility pattern of miracidia could be defined by computer vision and used as a diagnostic criterion. To develop motility pattern-based diagnostics of schistosomiasis using simple imaging devices, we analyzed Paramecium as a model for the schistosome miracidium. As a model for invasive nematodes, such as strongyloids and filaria, we examined a different type of motility in the apathogenic nematode Turbatrix, the “vinegar eel.” The results of motion time and frequency analysis suggest that target motility may be expressed as specific spectrograms serving as “diagnostic fingerprints.”

  12. Schistosome infection intensity is inversely related to auto-reactive antibody levels.

    Directory of Open Access Journals (Sweden)

    Francisca Mutapi

    2011-05-01

    Full Text Available In animal experimental models, parasitic helminth infections can protect the host from auto-immune diseases. We conducted a population-scale human study investigating the relationship between helminth parasitism and auto-reactive antibodies and the subsequent effect of anti-helminthic treatment on this relationship. Levels of antinuclear antibodies (ANA and plasma IL-10 were measured by enzyme linked immunosorbent assay in 613 Zimbabweans (aged 2-86 years naturally exposed to the blood fluke Schistosoma haematobium. ANA levels were related to schistosome infection intensity and systemic IL-10 levels. All participants were offered treatment with the anti-helminthic drug praziquantel and 102 treated schoolchildren (5-16 years were followed up 6 months post-antihelminthic treatment. ANA levels were inversely associated with current infection intensity but were independent of host age, sex and HIV status. Furthermore, after allowing for the confounding effects of schistosome infection intensity, ANA levels were inversely associated with systemic levels of IL-10. ANA levels increased significantly 6 months after anti-helminthic treatment. Our study shows that ANA levels are attenuated in helminth-infected humans and that anti-helminthic treatment of helminth-infected people can significantly increase ANA levels. The implications of these findings are relevant for understanding both the aetiology of immune disorders mediated by auto-reactive antibodies and in predicting the long-term consequences of large-scale schistosomiasis control programs.

  13. A Label-Free Microelectrode Array Based on One-Step Synthesis of Chitosan–Multi-Walled Carbon Nanotube–Thionine for Ultrasensitive Detection of Carcinoembryonic Antigen

    Directory of Open Access Journals (Sweden)

    Huiren Xu

    2016-07-01

    Full Text Available Carcinoembryonic antigen (CEA has been an extensively used tumor marker responsible for clinical early diagnosis of cervical carcinomas, and pancreatic, colorectal, gastric and lung cancer. Combined with micro-electro mechanical system (MEMS technology, it is important to develop a novel immune microelectrode array (MEA not only for rapid analysis of serum samples, but also for cell detection in vitro and in vivo. In this work, we depict a simple approach to modify chitosan–multi-walled carbon nanotubes–thionine (CS–MWCNTs–THI hybrid film through one-step electrochemical deposition and the CS-MWCNTs-THI hybrid films are successfully employed to immobilize anti-CEA for fabricating simple, label-free, and highly sensitive electro-chemical immune MEAs. The detection principle of immune MEA was based on the fact that the increasing formation of the antigen-antibody immunocomplex resulted in the decreased response currents and the relationship between the current reductions with the corresponding CEA concentrations was directly proportional. Experimental results indicated that the label-free MEA had good selectivity and the limit of detection for CEA is 0.5 pg/mL signal to noise ratio (SNR = 3. A linear calibration plot for the detection of CEA was obtained in a wide concentration range from 1 pg/mL to 100 ng/mL (r = 0.996. This novel MEA has potential applications for detecting CEA for the research on cancer cells and cancer tissue slices as well as for effective early diagnosis.

  14. Improved detection of equine antibodies against Sarcocystis neurona using polyvalent ELISAs based on the parasite SnSAG surface antigens.

    Science.gov (United States)

    Yeargan, Michelle R; Howe, Daniel K

    2011-02-28

    Equine protozoal myeloencephalitis (EPM) is a common neurologic disease of horses that is caused by the apicomplexan pathogen Sarcocystis neurona. To help improve serologic diagnosis of S. neurona infection, we have modified existing enzyme-linked immunosorbent assays (ELISAs) based on the immunogenic parasite surface antigens SnSAG2, SnSAG3, and SnSAG4 to make the assays polyvalent, thereby circumventing difficulties associated with parasite antigenic variants and diversity in equine immune responses. Two approaches were utilized to achieve polyvalence: (1) mixtures of the individual recombinant SnSAGs (rSnSAGs) were included in single ELISAs; (2) a collection of unique SnSAG chimeras that fused protein domains from different SnSAG surface antigens into a single recombinant protein were generated for use in the ELISAs. These new assays were assessed using a defined sample set of equine sera and cerebrospinal fluids (CSFs) that had been characterized by Western blot and/or were from confirmed EPM horses. While all of the polyvalent ELISAs performed relatively well, the highest sensitivity and specificity (100%/100%) were achieved with assays containing the rSnSAG4/2 chimera (Domain 1 of SnSAG4 fused to SnSAG2) or using a mixture of rSnSAG3 and rSnSAG4. The rSnSAG4 antigen alone and the rSnSAG4/3 chimera (Domain 1 of SnSAG4 fused to Domain 2 of SnSAG3) exhibited the next best accuracy at 95.2% sensitivity and 100% specificity. Binding ratios and percent positivity (PP) ratios, determined by comparing the mean values for positive versus negative samples, showed that the most advantageous signal to noise ratios were provided by rSnSAG4 and the rSnSAG4/3 chimera. Collectively, our results imply that a polyvalent ELISA based on SnSAG4 and SnSAG3, whether as a cocktail of two proteins or as a single chimeric protein, can give optimal results in serologic testing of serum or CSF for the presence of antibodies against S. neurona. The use of polyvalent SnSAG ELISAs will

  15. High voltage-derived enhancement of electric conduction in nanogap devices for detection of prostate-specific antigen

    Science.gov (United States)

    Park, Hyung Ju; Chi, Young Shik; Choi, Insung S.; Yun, Wan Soo

    2010-07-01

    We report a simple method of enhancing electric conductance in nanogap devices without any additional treatments, such as silver-enhancing process. The low electric conductance after selective immobilization of biofunctionalized gold nanoparticles in the gap region was greatly enhanced by repeated I-V scans at relatively high voltage ranges of -5 to 5 V, which was attributed to the formation of a new conduction pathway across the gap. The higher conduction state of the nanogap device showed a very stable I-V curve, which was used as an excellent measure of the existence of prostate-specific antigen.

  16. Radioimmunoassays of hidden viral antigens

    International Nuclear Information System (INIS)

    Neurath, A.R.; Strick, N.; Baker, L.; Krugman, S.

    1982-01-01

    Antigens corresponding to infectious agents may be present in biological specimens only in a cryptic form bound to antibodies and, thus, may elude detection. We describe a solid-phase technique for separation of antigens from antibodies. Immune complexes are precipitated from serum by polyethylene glycol, dissociated with NaSCN, and adsorbed onto nitrocellulose or polystyrene supports. Antigens remain topographically separated from antibodies after removal of NaSCN and can be detected with radiolabeled antibodies. Genomes from viruses immobilized on nitrocellulose can be identified by nucleic acid hybridization. Nanogram quantities of sequestered hepatitis B surface and core antigens and picogram amounts of hepatitis B virus DNA were detected. Antibody-bound adenovirus, herpesvirus, and measles virus antigens were discerned by the procedure

  17. Age-related worm load and worm fecundity patterns in human populations, as indicated by schistosome circulating antigens

    Directory of Open Access Journals (Sweden)

    Polman Katja

    1998-01-01

    Full Text Available Recently, our group determined the relationship between serum CAA levels and fecal egg counts in two foci with very intense Schistosoma mansoni transmission: Maniema (Zaire, an area endemic for S. mansoni since several decades, and Ndombo (Senegal, where transmission has only been established since a few years. The objective was to study and compare age-related worm load and worm fecundity patterns in these two different endemic settings. Here, we will summarize the most important findings and conclusions of this study.

  18. Hepatosplenomegaly is associated with low regulatory and Th2 responses to schistosome antigens in childhood schistosomiasis and malaria coinfection

    DEFF Research Database (Denmark)

    Wilson, Shona; Jones, Francis M.; Mwatha, Joseph K.

    2008-01-01

    in response to stimulation with SEA were high, and a negative association between presentation with hepatomegaly and the levels of the regulatory cytokines interleukin-6 and transforming growth factor beta(1) suggests that a possible mechanism for childhood hepatomegaly in areas where both malaria...... hepatosplenomegaly or infection with S. mansoni or P. falciparum. In comparison, SEA-specific Th2 cytokine responses were low, and the levels were negatively correlated with S. mansoni infection intensities and were lower among children who were coinfected with P. falciparum. Tumor necrosis factor alpha levels...

  19. Surface antigens and potential virulence factors from parasites detected by comparative genomics of perfect amino acid repeats

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    Adler Joël

    2007-12-01

    Full Text Available Abstract Background Many parasitic organisms, eukaryotes as well as bacteria, possess surface antigens with amino acid repeats. Making up the interface between host and pathogen such repetitive proteins may be virulence factors involved in immune evasion or cytoadherence. They find immunological applications in serodiagnostics and vaccine development. Here we use proteins which contain perfect repeats as a basis for comparative genomics between parasitic and free-living organisms. Results We have developed Reptile http://reptile.unibe.ch, a program for proteome-wide probabilistic description of perfect repeats in proteins. Parasite proteomes exhibited a large variance regarding the proportion of repeat-containing proteins. Interestingly, there was a good correlation between the percentage of highly repetitive proteins and mean protein length in parasite proteomes, but not at all in the proteomes of free-living eukaryotes. Reptile combined with programs for the prediction of transmembrane domains and GPI-anchoring resulted in an effective tool for in silico identification of potential surface antigens and virulence factors from parasites. Conclusion Systemic surveys for perfect amino acid repeats allowed basic comparisons between free-living and parasitic organisms that were directly applicable to predict proteins of serological and parasitological importance. An on-line tool is available at http://genomics.unibe.ch/dora.

  20. Detection and confirmation of PPR virus antigen in sheep and goats by sandwich-ELISA and RT-PCR in Andhra Pradesh, India

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    G. Saritha

    2015-06-01

    Full Text Available Peste des petits ruminants (PPR is a highly contagious disease of domestic and wild small ruminants. Rapid and accurate laboratory assay are essential to enable the implementation of appropriate control strategies to restrict the spread of PPR. The present study was designed to detect the PPR virus (PPRV antigen (N-gene in nasal swabs and tissue samples. A total of 195 samples comprising of 138 nasal swabs from PPR suspected sheep (n=72 and goats (n=66, and 57 tissue samples comprising of lymph nodes from dead sheep (n=39 and goats (n=18 were collected from certain parts of Andhra Pradesh. The samples were subjected to sandwich-ELISA followed by RT-PCR for confirmatory diagnosis. In this study, PPRV could be detected in 27.53% (n=38/138 nasal swabs and 49.12% (n=28/57 tissue samples. Data showed that PPRV infection is widespread in the Andhra Pradesh, India.

  1. The hybrid EIA test: a specific and sensitive assay for the detection of woodchuck antibody to hepatitis surface antigen (anti-WHs).

    Science.gov (United States)

    Millman, I; Glass, R G

    1988-05-01

    'Ausria II' polystyrene beads (Abbott Labs, N. Chicago) are reacted with woodchuck serum positive for WHsAg in a dilution predetermined by titration. This modified bead is used in a blocking assay to detect the presence of antibody to the surface antigen of woodchuck hepatitis virus (anti-WHs). Serum containing woodchuck anti-WHs and commercial horseradish peroxidase (HRP) labeled anti-HBs are sequentially added. A drop in optical density at 492 nm of 50% or more due to the blocking of HRP conjugated anti-HBs by anti-WHs compared with a control (negative woodchuck serum) is a measure of anti-WHs. The ease and simplicity of converting readily available 'Ausria II' beads to specific reagents for detecting anti-WHs should be welcomed by investigators studying WHV. The method described is both sensitive and reproducible.

  2. Extended flow cytometry characterization of normal bone marrow progenitor cells by simultaneous detection of aldehyde dehydrogenase and early hematopoietic antigens: implication for erythroid differentiation studies

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    Pascariello Caterina

    2008-05-01

    Full Text Available Abstract Background Aldehyde dehydrogenase (ALDH is a cytosolic enzyme highly expressed in hematopoietic precursors from cord blood and granulocyte-colony stimulating factor mobilized peripheral blood, as well as in bone marrow from patients with acute myeloblastic leukemia. As regards human normal bone marrow, detailed characterization of ALDH+ cells has been addressed by one single study (Gentry et al, 2007. The goal of our work was to provide new information about the dissection of normal bone marrow progenitor cells based upon the simultaneous detection by flow cytometry of ALDH and early hematopoietic antigens, with particular attention to the expression of ALDH on erythroid precursors. To this aim, we used three kinds of approach: i multidimensional analytical flow cytometry, detecting ALDH and early hematopoietic antigens in normal bone marrow; ii fluorescence activated cell sorting of distinct subpopulations of progenitor cells, followed by in vitro induction of erythroid differentiation; iii detection of ALDH+ cellular subsets in bone marrow from pure red cell aplasia patients. Results In normal bone marrow, we identified three populations of cells, namely ALDH+CD34+, ALDH-CD34+ and ALDH+CD34- (median percentages were 0.52, 0.53 and 0.57, respectively. As compared to ALDH-CD34+ cells, ALDH+CD34+ cells expressed the phenotypic profile of primitive hematopoietic progenitor cells, with brighter expression of CD117 and CD133, accompanied by lower display of CD38 and CD45RA. Of interest, ALDH+CD34- population disclosed a straightforward erythroid commitment, on the basis of three orders of evidences. First of all, ALDH+CD34- cells showed a CD71bright, CD105+, CD45- phenotype. Secondly, induction of differentiation experiments evidenced a clear-cut expression of glycophorin A (CD235a. Finally, ALDH+CD34- precursors were not detectable in patients with pure red cell aplasia (PRCA. Conclusion Our study, comparing surface antigen expression of

  3. Diagnostic performances of two rapid tests for detection of feline leukemia virus antigen in sera of experimentally feline leukemia virus-infected cats

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    Matthew R Krecic

    2017-12-01

    Full Text Available Objectives The objective of this study was to compare the diagnostic sensitivities and specificities of WITNESS FeLV-FIV (Zoetis and SNAP FIV/FeLV Combo Test (IDEXX for the detection of FeLV p27 antigen in the sera of experimentally feline leukemia virus (FeLV-infected cats. Methods Diagnostic sensitivities of WITNESS and SNAP were determined through testing of 47 serum samples collected from cats day 56 post-experimental infection with a virulent FeLV Rickard strain. Successful experimental infection was confirmed based on observation of FeLV antigen and proviral DNA in anti-coagulated (EDTA whole-blood samples by immunofluorescent antibody (IFA test and PCR, respectively. Diagnostic specificities of both tests were determined through testing of sera of 92 laboratory-housed, non-FeLV-exposed specific pathogen-free (SPF cats. Results Forty-one of 47 blood samples were IFA positive, whereas all 47 samples were PCR positive. All 92 non-FeLV-infected SPF cats were IFA and PCR negative. In comparison to IFA as the reference method, both WITNESS and SNAP tests yielded equivalent sensitivities and specificities of 100% and 97.8%, respectively. In comparison to PCR as the reference method, both WITNESS and SNAP tests likewise performed equivalently, with sensitivities and specificities of 91.5% and 100%, respectively. Conclusions and relevance Sensitivity and specificity of WITNESS FeLV-FIV for identifying FeLV p27 antigen in the sera of these experimentally FeLV-infected and non-FeLV-exposed SPF cats equaled those of the SNAP FIV/FeLV Combo Test. However, all positive results, regardless of the point-of-care test used, should be confirmed before making clinical decisions such as segregation from other cats or euthanasia.

  4. CdSe/ZnS Quantum Dot-Labeled Lateral Flow Strips for Rapid and Quantitative Detection of Gastric Cancer Carbohydrate Antigen 72-4

    Science.gov (United States)

    Yan, Xinyu; Wang, Kan; Lu, Wenting; Qin, Weijian; Cui, Daxiang; He, Jinghua

    2016-03-01

    Carbohydrate antigen 72-4 (CA72-4) is an important biomarker associated closely with diagnosis and prognosis of early gastric cancer. How to realize quick, sensitive, specific, and quantitative detection of CA72-4 in clinical specimens has become a great requirement. Herein, we reported a CdSe/ZnS quantum dot-labeled lateral flow test strip combined with a charge-coupled device (CCD)-based reader was developed for rapid, sensitive, and quantitative detection of CA72-4. Two mouse monoclonal antibodies (mAbs) against CA72-4 were employed. One of them was coated as a test line, while another mAb was labeled with quantum dots and coated onto conjugate pad. The goat anti-mouse IgG was immobilized as a control line. After sample was added, a sandwich structure was formed with CA72-4 and these two mAbs. The fluorescent signal from quantum dots (QD)-labeled mAb in sandwich structure was related to the amount of detected CA72-4. A CCD-based reader was used to realize quantitative detection of CA72-4. Results showed that developed QD-labeled lateral flow strips to detect CA72-4 biomarker with the sensitivity of 2 IU/mL and 10 min detection time. One hundred sera samples from clinical patients with gastric cancer and healthy people were used to confirm specificity of this strip method; results showed that established strip method own 100 % reproducibility and 100 % specificity compared with Roche electrochemiluminescence assay results. In conclusion, CdSe/ZnS quantum dot-labeled lateral flow strips for detection of CA72-4 could realize rapid, sensitive, and specific detection of clinical samples and could own great potential in clinical translation in near future.

  5. Splenic artery ligature associated with endoscopic banding for schistosomal portal hypertension.

    Science.gov (United States)

    Colaneri, Renata Potonyacz; Coelho, Fabrício Ferreira; de Cleva, Roberto; Perini, Marcos Vinícius; Herman, Paulo

    2014-11-28

    To propose a less invasive surgical treatment for schistosomal portal hypertension. Ten consecutive patients with hepatosplenic schistosomiasis and portal hypertension with a history of upper gastrointestinal hemorrhage from esophageal varices rupture were evaluated in this study. Patients were subjected to a small supraumbilical laparotomy with the ligature of the splenic artery and left gastric vein. During the procedure, direct portal vein pressure before and after the ligatures was measured. Upper gastrointestinal endoscopy was performed at the 30(th) postoperative day, when esophageal varices diameter were measured and band ligature performed. During follow-up, other endoscopic procedures were performed according to endoscopy findings. There was no intra-operative mortality and all patients had confirmed histologic diagnoses of schistosomal portal hypertension. During the immediate postoperative period, two of the ten patients had complications, one characterized by a splenic infarction, and the other by an incision hematoma. Mean hospitalization time was 4.1 d (range: 2-7 d). Pre- and post-operative liver function tests did not show any significant changes. During endoscopy thirty days after surgery, a decrease in variceal diameters was observed in seven patients. During the follow-up period (57-72 mo), endoscopic therapy was performed and seven patients had their varices eradicated. Considering the late postoperative evaluation, nine patients had a decrease in variceal diameters. A mean of 3.9 endoscopic banding sessions were performed per patient. Two patients presented bleeding recurrence at the late postoperative period, which was controlled with endoscopic banding in one patient due to variceal rupture and presented as secondary to congestive gastropathy in the other patient. Both bleeding episodes were of minor degree with no hemodynamic consequences or need for blood transfusion. Ligature of the splenic artery and left gastric vein with supraumbilical

  6. Detection of Galactomannan Antigenemia in Patients Receiving Piperacillin-Tazobactam and Correlations between In Vitro, In Vivo, and Clinical Properties of the Drug-Antigen Interaction

    Science.gov (United States)

    Walsh, Thomas J.; Shoham, Shmuel; Petraitiene, Ruta; Sein, Tin; Schaufele, Robert; Kelaher, Amy; Murray, Heidi; Mya-San, Christine; Bacher, John; Petraitis, Vidmantas

    2004-01-01

    Recent case reports describe patients receiving piperacillin-tazobactam who were found to have circulating galactomannan detected by the double sandwich enzyme-linked immunosorbent assay (ELISA) system, leading to the false presumption of invasive aspergillosis. Since this property of piperacillin-tazobactam and galactomannan ELISA is not well understood, we investigated the in vitro, in vivo, and clinical properties of this interaction. Among the 12 reconstituted antibiotics representing four classes of antibacterial compounds that are commonly used in immunocompromised patients, piperacillin-tazobactam expressed a distinctively high level of galactomannan antigen in vitro (P = 0.001). After intravenous infusion of piperacillin-tazobactam into rabbits, the serum galactomannan index (GMI) in vivo changed significantly (P = 0.0007) from a preinfusion mean baseline value of 0.27 to a mean GMI of 0.83 by 30 min to slowly decline to a mean GMI of 0.44 24 h later. Repeated administration of piperacillin-tazobactam over 7 days resulted in accumulation of circulating galactomannan to a mean peak GMI of 1.31 and a nadir of 0.53. Further studies revealed that the antigen reached a steady state by the third day of administration of piperacillin-tazobactam. Twenty-six hospitalized patients with no evidence of invasive aspergillosis who were receiving antibiotics and ten healthy blood bank donors were studied for expression of circulating galactomannan. Patients (n = 13) receiving piperacillin-tazobactam had significantly greater mean serum GMI values (0.74 ± 0.14) compared to patients (n = 13) receiving other antibiotics (0.14 ± 0.08) and compared to healthy blood bank donors (0.14 ± 0.06) (P 0.5 compared to none of thirteen subjects receiving other antibiotics (P = 0.039) and to none of ten healthy blood bank donors (P = 0.046). These data demonstrate that among antibiotics that are commonly used in immunocompromised patients, only piperacillin-tazobactam contains

  7. Establishment of the cross-clade antigen detection system for H5 subtype influenza viruses using peptide monoclonal antibodies specific for influenza virus H5 hemagglutinin.

    Science.gov (United States)

    Takahashi, Hitoshi; Nagata, Shiho; Odagiri, Takato; Kageyama, Tsutomu

    2018-04-15

    The H5 subtype of highly pathogenic avian influenza (H5 HPAI) viruses is a threat to both animal and human public health and has the potential to cause a serious future pandemic in humans. Thus, specific and rapid detection of H5 HPAI viruses is required for infection control in humans. To develop a simple and rapid diagnostic system to detect H5 HPAI viruses with high specificity and sensitivity, we attempted to prepare monoclonal antibodies (mAbs) that specifically recognize linear epitopes in hemagglutinin (HA) of H5 subtype viruses. Nine mAb clones were obtained from mice immunized with a synthetic partial peptide of H5 HA molecules conserved among various H5 HPAI viruses. The antigen-capture enzyme-linked immunosorbent assay using the most suitable combination of these mAbs, which bound specifically to lysed H5 HA under an optimized detergent condition, was specific for H5 viruses and could broadly detect H5 viruses in multiple different clades. Taken together, these peptide mAbs, which recognize linear epitopes in a highly conserved region of H5 HA, may be useful for specific and highly sensitive detection of H5 HPAI viruses and can help in the rapid diagnosis of human, avian, and animal H5 virus infections. Copyright © 2018 Elsevier Inc. All rights reserved.

  8. Long-term Maintenance of CD4 T Cell Memory Responses to Malaria Antigens in Malian Children Coinfected with Schistosoma haematobium

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    Kirsten E. Lyke

    2018-02-01

    Full Text Available Polyparasitism is common in the developing world. We have previously demonstrated that schistosomiasis-positive (SP Malian children, aged 4–8 years, are protected from malaria compared to matched schistosomiasis-negative (SN children. The effect of concomitant schistosomiasis upon acquisition of T cell memory is unknown. We examined antigen-specific T cell frequencies in 48 Malian children aged 4–14 to a pool of malaria blood stage antigens, and a pool of schistosomal antigens, at a time point during a malaria episode and at a convalescent time point ~6 months later, following cessation of malaria transmission. CD4+ T cell-derived memory responses, defined as one or more significant cytokine (IFN-γ, TNF-α, IL-2, and/or IL-17A responses, was measured to schistoma antigens in 18/23 SP children at one or both time points, compared to 4/23 SN children (P < 0.0001. At the time of malaria infection, 12/24 SN children and 15/23 SP children (P = 0.29 stimulated with malaria antigens demonstrated memory recall as defined by CD4-derived cytokine production. This compares to 7/23 SN children and 16/23 SP children (P = 0.009 at the convalescent timepoint. 46.2% of cytokine-producing CD4+ T cells expressed a single cytokine after stimulation with malaria antigen during the malaria episode. This fell to 40.9% at follow-up with a compensatory rise of multifunctional cytokine secretion over time, a phenomenon consistent with memory maturation. The majority (53.2–59.5% of responses derived from CD45RA−CD62L− effector memory T cells with little variation in the phenotype depending upon the time point or the study cohort. We conclude that detectable T cell memory responses can be measured against both malaria and schistosoma antigens and that the presence of Schistosoma haematobium may be associated with long-term maintenance of T memory to malaria.

  9. Two competitive enzyme immunoassays for the detection of IgG class antibodies to hepatitis a antigen

    Directory of Open Access Journals (Sweden)

    Claudia Lamarca Vitral

    1991-06-01

    Full Text Available Two competitive enzyme immunoassays (EIA techniques were developed: in the first (COMP-1, test sera were added together with HAV antigen on anti-HAV IgG-coated wells followed by an anti-HA VHRP conjugate; in the second (COMP-2, test sera and anti-HA VHRP conjugate competed for HAV epitopes previously adsorbed to anti-HA V IgG-coated wells. Both procedures used tetramethylbenzidine (TMB as a substrate. Both competitive tests were shown to be reproducible and suitable for routine diagnosis and research purposes.Foram desenvolvidos dois ensaios imunoenzimáticos (EIA competitivos: no primeiro (COMP-1 colocou-se numa placa sensibilizada com anti-HAVIgG as amostras teste juntamente como antígeno HA Vea seguir o conjugado anti-HA VHRP; no segundo (COMP-2, as amostras teste e o conjugado anti-HAV HRP competem pelos epitopos do antígeno HAV previamente absorvido na placa sensibilizada do anti-HAV IgG. O substrato utilizado foi tetrametilbenzidina (TMB. Ambas as técnicas mostraram ser produtíveis e aplicáveis para fins de diagnóstico e pesquisa.

  10. A disposable electrochemical immunosensor based on carbon screen-printed electrodes for the detection of prostate specific antigen.

    Science.gov (United States)

    Yan, Mei; Zang, Dejin; Ge, Shenguang; Ge, Lei; Yu, Jinghua

    2012-01-01

    A novel screen-printed electrode (SPEs) on sheets of vegetable parchment was prepared. The obtained SPEs were stable, convenient, inexpensive and suitable for large-area screen-printing. With these SPEs, we explored the fabrication of a novel, disposable and highly sensitive electro-analytical immunosensor using graphene nanosheets (GS) and horseradish peroxidase (HRP)-labeled signal antibody functionalized with gold nanoparticles (HRP-Ab(2)/Au NPs). GS was used to increase the conductivity and stability of this immunosensor due to its fast electron transportation and good biocompatibility. Au NPs could not only provide a large surface area for the immobilization of HRP-Ab(2) but also enhance the electroreduction between HRP and H(2)O(2) to amplify the electrochemical signal on the sandwich immuno-complexes modified SPEs. The proposed SPEs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electrochemical methods involving cyclic voltammetry (CV), and electrochemical impedence method. Using prostate specific antigen (PSA) as a model analyte, this immunosensor showed a wide linear range over 6 orders of magnitude with the minimum value down to 2 pg mL(-1). In addition, this immunosensor could avoid the need of deoxygenation for the electrochemical immunoassay. Thus, it provided a promising potential in clinical applications. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Using reduced graphene oxide-Ca:CdSe nanocomposite to enhance photoelectrochemical activity of gold nanoparticles functionalized tungsten oxide for highly sensitive prostate specific antigen detection.

    Science.gov (United States)

    Wang, Xueping; Xu, Rui; Sun, Xu; Wang, Yaoguang; Ren, Xiang; Du, Bin; Wu, Dan; Wei, Qin

    2017-10-15

    An ultrasensitive sandwich-type photoelectrochemical (PEC) immunosensor was constructed for the detection of prostate specific antigen (PSA). In this work, Au-nanoparticle-loaded tungsten oxide (WO 3 -Au) hybrid composites was applied as PEC sensing platform, while Ca ions doped CdSe equipped on the conducting framework of reduced graphene oxide (rGO-Ca:CdSe) nanocomposites were employed as the signal amplification probe. As for WO 3 -Au, massive Au nanoparticles were formed on the surface of WO 3 without any additional reducing agent, providing a novel nanocarriers for anchoring plenty of the primary antibodies due to the large specific surface area and good biocompatibility by chemical bonding between Au nanoparticles and -NH 2 of antibodies. Besides, the incorporation of the rGO and the doping of Ca ions could improve the conductivity and hinder the recombination of electron-hole pairs of CdSe nanoparticles effectively, thereby enhancing the photocurrent conversion efficiency. Based on the sandwich immunoreaction, the primary antibody was immobilized onto WO 3 -Au substrate, after the formed rGO-Ca:CdSe labels were captured onto the electrode surface via the specific antibody-antigen interaction, the photocurrent intensity could be further enhanced due to the sensitization effect. Under the optimal conditions, the proposed PEC immunosensor shows a linear relationship between photocurrent variation and the logarithm of PSA concentration in the wide range of 5pgmL -1 to 50ngmL -1 with a low detection limit of 2.6pgmL -1 (S/N=3). Moreover, it also presented good stability and acceptable specificity, indicating the potential applications in clinical diagnostics. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Diagnostic efficacy of monoclonal antibody based sandwich enzyme linked immunosorbent assay (ELISA for detection of Fasciola gigantica excretory/secretory antigens in both serum and stool

    Directory of Open Access Journals (Sweden)

    Zoheiry Mona K

    2011-09-01

    Full Text Available Abstract Background This research was carried out to develop a reliable monoclonal antibody (MoAb-based sandwich enzyme linked immunosorbent assay (ELISA for the diagnosis of active Fasciola gigantica infection in both serum and stool for comparative purposes. Methods From a panel of MoAbs raised against F. gigantica excretory/secretory antigens (ES Ags, a pair (12B/11D/3F and 10A/9D/10G was chosen due to its high reactivity and strict specificity to F. gigantica antigen by indirect ELISA. Results The two MoAbs were of the IgG1 and IgG2a subclasses, respectively. Using SDS-PAGE and EITB, the selected MoAbs recognized 83, 64, 45 and 26 kDa bands of ES Ags. The lower detection limit of ELISA assay was 3 ng/ml. In stool, the sensitivity, specificity and diagnostic efficacy of ELISA was 96%, 98.2 and 97.1%; while in serum they were 94%, 94.6% and 94.3%, respectively. Moreover, a positive correlation was found between ova count in stool of F. gigantica infected patients and the OD readings of ELISA in both stool and serum samples (r = 0.730, p Conclusions These data showed that the use of MoAb-based sandwich ELISA for the detection of F. gigantica coproantigens in stool specimens was superior to serum samples; it provides a highly efficient, non-invasive technique for the diagnosis of active F. gigantica infection.

  13. Comparison of clinical performance of antigen basedenzyme immunoassay (EIA and major outer membrane protein (MOMP-PCR for detection of genital Chlamydia trachomatis infection

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    Mahmoud Nateghi Rostami

    2016-06-01

    Full Text Available Background: Chlamydia trachomatis is the most common sexually transmitted bacterial pathogen worldwide. Early detection and treatment of C.trachomatis genital infection prevent serious reproductive complications. Objective: Performances of enzyme immunoassay (EIA and major outer membrane protein (MOMP-polymerase chain reaction (PCR for diagnosis of genital C.trachomatis infection in women were compared. Materials and Methods: In this cross sectional study a total of 518 women volunteers were included (33.67±8.3 yrs who had been referred to Gynecology clinics of Qom province, Iran, were included. Endocervical swab specimens were collected to detect lipopolysaccharide (LPS antigen in EIA and to amplify MOMP gene of C.trachomatis in PCR. Results were confirmed using ompI nested-PCR. Sensitivity, specificity, positive (PPV and negative predictive values (NPV were calculated for performance of the tests. Odds ratios were determined using binary logistic regression analysis. Results: In total, 37 (7.14% cases were positive by EIA and/or MOMP-PCR. All discrepant results were confirmed by nested-PCR. Sensitivity, specificity, PPV and NPV values of EIA were 59.46%, 100%, 100% and 96.98%, and those of MOMPPCR were 97.30%, 100%, 100%, 99.79%, respectively. Reproductive complications including 2.7% ectopic pregnancy, 5.4% stillbirth, 5.4% infertility, and 10.8% PROM were recorded. The risk of developing chlamydiosis was increased 4.8-fold in volunteers with cervicitis (p<0.05; OR 4.80; 95% CI 1.25-18.48. Conclusion: C.trachomatis infection should be regarded in women of reproductive ages especially those with cervicitis. Primary screening of women by using the low cost antigen-EIA is recommended; however, due to the low sensitivity of Ag-EIA, verification of the negative results by a DNA amplification method is needed.

  14. Comparison of clinical performance of antigen based-enzyme immunoassay (EIA) and major outer membrane protein (MOMP)-PCR for detection of genital Chlamydia trachomatis infection.

    Science.gov (United States)

    Nateghi Rostami, Mahmoud; Hossein Rashidi, Batool; Aghsaghloo, Fatemeh; Nazari, Razieh

    2016-06-01

    Chlamydia trachomatis is the most common sexually transmitted bacterial pathogen worldwide. Early detection and treatment of C.trachomatis genital infection prevent serious reproductive complications. Performances of enzyme immunoassay (EIA) and major outer membrane protein (MOMP)-polymerase chain reaction (PCR) for diagnosis of genital C.trachomatis infection in women were compared. In this cross sectional study a total of 518 women volunteers were included (33.67±8.3 yrs) who had been referred to Gynecology clinics of Qom province, Iran, were included. Endocervical swab specimens were collected to detect lipopolysaccharide (LPS) antigen in EIA and to amplify MOMP gene of C.trachomatis in PCR. Results were confirmed using ompI nested-PCR. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were calculated for performance of the tests. Odds ratios were determined using binary logistic regression analysis. In total, 37 (7.14%) cases were positive by EIA and/or MOMP-PCR. All discrepant results were confirmed by nested-PCR. Sensitivity, specificity, PPV and NPV values of EIA were 59.46%, 100%, 100% and 96.98%, and those of MOMP-PCR were 97.30%, 100%, 100%, 99.79%, respectively. Reproductive complications including 2.7% ectopic pregnancy, 5.4% stillbirth, 5.4% infertility, and 10.8% PROM were recorded. The risk of developing chlamydiosis was increased 4.8-fold in volunteers with cervicitis (p<0.05; OR 4.80; 95% CI 1.25-18.48). C.trachomatis infection should be regarded in women of reproductive ages especially those with cervicitis. Primary screening of women by using the low cost antigen-EIA is recommended; however, due to the low sensitivity of Ag-EIA, verification of the negative results by a DNA amplification method is needed.

  15. Evaluation of two new commercial tests for the diagnosis of acute dengue virus infection using NS1 antigen detection in human serum.

    Science.gov (United States)

    Dussart, Philippe; Petit, Laure; Labeau, Bhety; Bremand, Laetitia; Leduc, Alexandre; Moua, David; Matheus, Séverine; Baril, Laurence

    2008-08-20

    We compared the performance of two new commercial tests for the detection of dengue NS1 protein during the clinical phase of dengue virus (DENV) infection-an immunochromatographic test allowing rapid detection of the NS1 antigen, Dengue NS1 Ag STRIP (Bio-Rad Laboratories - Marnes La Coquette, France), and a two-step sandwich-format microplate enzyme-linked immunosorbent assay (ELISA), pan-E Dengue Early ELISA (Panbio - Brisbane, Australia)-with a one-step sandwich-format microplate ELISA, the Platelia Dengue NS1 Ag test (Bio-Rad). We tested 272 serum samples from patients with dengue disease. Of these, 222 were from patients with acute infection of one of the four dengue serotypes, detected by RT-PCR and/or virus isolation. Forty-eight acute-phase serum samples from patients not infected with dengue virus were also included. The sensitivity of the Platelia Dengue NS1 Ag test on acute serum samples (n = 222) was 87.4% (95% confidence interval: 82.3% to 91.5%); that of Dengue NS1 Ag STRIP was 81.5% (95% CI: 75.8% to 86.4%) after 15 minutes and 82.4% (95% CI: 76.8% to 87.2%) after 30 minutes. Both tests had a specificity of 100% (97.5% CI, one-sided test: 92.6% to 100.0%). The pan-E Dengue Early ELISA had a sensitivity of 60.4% (95% CI: 53.4% to 66.8%) and a specificity of 97.9% (95% CI: 88.9% to 99.9%). Our findings support the use of diagnostic tools based on the NS1 antigen detection for the diagnosis of acute DENV infection. The immunochromatographic test, Dengue NS1 Ag STRIP-the first rapid diagnostic test for DENV infection-was highly sensitive and specific, and would therefore be a suitable first-line test in the field. The pan-E Dengue Early ELISA was less sensitive than the Platelia test; this two-step ELISA should be combined with DENV IgM antibody detection for the diagnosis of DENV infection.

  16. Evaluation of two new commercial tests for the diagnosis of acute dengue virus infection using NS1 antigen detection in human serum.

    Directory of Open Access Journals (Sweden)

    Philippe Dussart

    Full Text Available BACKGROUND: We compared the performance of two new commercial tests for the detection of dengue NS1 protein during the clinical phase of dengue virus (DENV infection-an immunochromatographic test allowing rapid detection of the NS1 antigen, Dengue NS1 Ag STRIP (Bio-Rad Laboratories - Marnes La Coquette, France, and a two-step sandwich-format microplate enzyme-linked immunosorbent assay (ELISA, pan-E Dengue Early ELISA (Panbio - Brisbane, Australia-with a one-step sandwich-format microplate ELISA, the Platelia Dengue NS1 Ag test (Bio-Rad. METHODS: We tested 272 serum samples from patients with dengue disease. Of these, 222 were from patients with acute infection of one of the four dengue serotypes, detected by RT-PCR and/or virus isolation. Forty-eight acute-phase serum samples from patients not infected with dengue virus were also included. RESULTS: The sensitivity of the Platelia Dengue NS1 Ag test on acute serum samples (n = 222 was 87.4% (95% confidence interval: 82.3% to 91.5%; that of Dengue NS1 Ag STRIP was 81.5% (95% CI: 75.8% to 86.4% after 15 minutes and 82.4% (95% CI: 76.8% to 87.2% after 30 minutes. Both tests had a specificity of 100% (97.5% CI, one-sided test: 92.6% to 100.0%. The pan-E Dengue Early ELISA had a sensitivity of 60.4% (95% CI: 53.4% to 66.8% and a specificity of 97.9% (95% CI: 88.9% to 99.9%. CONCLUSION: Our findings support the use of diagnostic tools based on the NS1 antigen detection for the diagnosis of acute DENV infection. The immunochromatographic test, Dengue NS1 Ag STRIP-the first rapid diagnostic test for DENV infection-was highly sensitive and specific, and would therefore be a suitable first-line test in the field. The pan-E Dengue Early ELISA was less sensitive than the Platelia test; this two-step ELISA should be combined with DENV IgM antibody detection for the diagnosis of DENV infection.

  17. Evaluation of Vitronectin Expression in Prostate Cancer and the Clinical Significance of the Association of Vitronectin Expression with Prostate Specific Antigen in Detecting Prostate Cancer.

    Science.gov (United States)

    Niu, Yue; Zhang, Ling; Bi, Xing; Yuan, Shuai; Chen, Peng

    2016-03-05

    To detect the expression of vitronectin (VTN) in the tissues and blood serum of prostate cancer (PCa) patients, and evaluate its clinical significance and to evaluate the significance of the combined assay of VTN and prostate specific antigens (PSA) in PCa diagnosis. To detect the expression of VTN as a potential marker for PCa diagnosis and prognosis, immunohistochemistry was performed on the tissues of 32 patients with metastatic PCa (PCaM), 34 patients with PCa without metastasis (PCa), and 41 patients with benign prostatic hyperplasia (BPH). The sera were then subjected to Western blot analysis. All cases were subsequently examined to determine the concentrations of PSA and VTN in the sera. The collected data were collated and analyzed. The positive expression rates of VTN in the tissues of the BPH and PCa groups (including PCa and PCaM groups) were 75.61% and 45.45%, respectively (P = .005). VTN was more highly expressed in the sera of the BPH patients (0.83 ± 0.07) than in the sera of the PCa patients (0.65 ± 0.06) (P < .05). It was also more highly expressed in the sera of the PCa patients than in the sera of the PCaM patients (0.35 ± 0.08) (P < .05). In the diagnosis of BPH and PCa, the Youden indexes of PSA detection, VTN detection, and combined detection were 0.2620, 0.3468, and 0.5635; the kappa values were 0.338, 0.304, and 0.448, respectively, and the areas under the receiver operating characteristic curve were 0.625, 0.673, and 0.703 (P < .05), respectively. VTN levels in sera may be used as a potential marker of PCa for the diagnosis and assessment of disease progression and metastasis. The combined detection of VTN and PSA in sera can be clinically applied in PCa diagnosis. .

  18. [Enzyme-linked immunosorbent assay (ELISA) for detection of antibodies to Salmonella Typhi lipopolysaccharide O and capsular polysaccharide Vi antigens in persons from outbreak of typhoid fever].

    Science.gov (United States)

    Rastawicki, Waldemar; Kałużewski, Stanisław

    2015-01-01

    The laboratory diagnosis of typhoid fever is dependent upon either isolation of S. Typhi from a clinical sample or the detection of raised titers of serum antibodies in the Widal test or the passive hemagglutination assay (PHA). In this study we evaluated the usefulness of ELISA for detection of antibodies to S. Typhi lipopolysaccharide O and capsular polysaccharide Vi antigens in the sera of persons from outbreak of typhoid fever. Fifteen serum samples from patients with laboratory confirmed typhoid fever and 140 sera from persons suspected for contact with typhoid fever patients from outbreak in 1974/75 in Poland were tested by ELISA. Additionally, as the control group, we tested 115 sera from blood donors for the presence of S. Typhi anti-LPS and anti-Vi antibodies. Anti-LPS and anti-Vi antibodies were detected in 80% and 53.3% of sera obtained from patients with laboratory confirmed typhoid fever, respectively. The high percentages of positive results in ELISA were also noted in the group of persons suspected for contact with typhoid fever patients (51.4% and 45%) but not in the group of blood donors (7.8% and 6.1%, respectively). The ELISA could be a useful tool for the serological diagnosis of typhoid fever in patients who have clinical symptoms but are culture negative, especially during massive outbreaks of typhoid fever.

  19. Detection of antibody against antigen expressed by molecularly cloned hepatitis C virus cDNA: Application to diagnosis and blood screening for posttransfusion hepatitis

    Energy Technology Data Exchange (ETDEWEB)

    Miyamura, Tatsuo; Saito, Izumu (National Institute of Health, Tokyo (Japan)); Katayama, Tohru (Tokyo National Chest Hospital (Japan)); Kikuchi, Shu; Tateda, Akira (Sendai National Hospital (Japan)); Houghton, M.; Choo, Quilim; Kuo, G. (Chiron Corporation, Emeryville, CA (USA))

    1990-02-01

    A cDNA clone has been derived from the plasma of a chimpanzee with chronic non-A, non-B viral hepatits (NANBH). The authors have assayed for antibodies reacting with the encoded antigen in sera from posttransfusion hepatitis patients (643 samples from 23 patients) and their corresponding donors collected during the past 10 years in Japan. The antibody was detected in 15 out of 17 (88.2%) posttransfusion NANBH (PT-NANBH) patients whose sera over time displayed multiple alanine aminotransferase (ALT) peaks. In general, the antibody was detected after several peaks of serum ALT elevations and, once detected, it persisted for years. Of the 15 well-defined cases of PT-NANBH that showed multiple ALT peaks and hepatitis C virus seroconversions, 11 (73.3%) were shown to be transfused with at least one unit of blood positive for the antibody. The retrospective analysis showed that all tested donor blood found to be positive for the antibody had been transfused to recipients who afterwards developed NANBH. These data strongly suggest that the cloned cDNA originated from an etiological agent of NANBH termed the hepatitis C virus. Furthermore, the present study demonstrates that had the screening been done with the anti-hepatitis C virus assay, 11 out of 17 (64.7%) cases of chronic PT-NANBH and 1 out of 6 (16.6%) acute PT-NANBH would have been prevented.

  20. Detection of antibody against antigen expressed by molecularly cloned hepatitis C virus cDNA: Application to diagnosis and blood screening for posttransfusion hepatitis

    International Nuclear Information System (INIS)

    Miyamura, Tatsuo; Saito, Izumu; Katayama, Tohru; Kikuchi, Shu; Tateda, Akira; Houghton, M.; Choo, Quilim; Kuo, G.

    1990-01-01

    A cDNA clone has been derived from the plasma of a chimpanzee with chronic non-A, non-B viral hepatits (NANBH). The authors have assayed for antibodies reacting with the encoded antigen in sera from posttransfusion hepatitis patients (643 samples from 23 patients) and their corresponding donors collected during the past 10 years in Japan. The antibody was detected in 15 out of 17 (88.2%) posttransfusion NANBH (PT-NANBH) patients whose sera over time displayed multiple alanine aminotransferase (ALT) peaks. In general, the antibody was detected after several peaks of serum ALT elevations and, once detected, it persisted for years. Of the 15 well-defined cases of PT-NANBH that showed multiple ALT peaks and hepatitis C virus seroconversions, 11 (73.3%) were shown to be transfused with at least one unit of blood positive for the antibody. The retrospective analysis showed that all tested donor blood found to be positive for the antibody had been transfused to recipients who afterwards developed NANBH. These data strongly suggest that the cloned cDNA originated from an etiological agent of NANBH termed the hepatitis C virus. Furthermore, the present study demonstrates that had the screening been done with the anti-hepatitis C virus assay, 11 out of 17 (64.7%) cases of chronic PT-NANBH and 1 out of 6 (16.6%) acute PT-NANBH would have been prevented

  1. Isolation and preservation of schistosome eggs and larvae in RNAlater® facilitates genetic profiling of individuals

    Directory of Open Access Journals (Sweden)

    Webster Bonnie L

    2009-10-01

    Full Text Available Abstract Although field-sampling procedures to capture gDNA from individual schistosome larval stages directly from their natural hosts exist, they do pose some technical and logistical challenges hampering certain epidemiological studies. The aim of this study was to develop, refine and evaluate an alternative methodology, which enables better preservation of large numbers of individual schistosome larval stages and eggs collected in low resource endemic areas, to provide PCR-quality DNA for multi-locus genetic analysis. The techniques reported here present simple and effective short-term field and long-term laboratory preservation and storage systems for individually sampled schistosome eggs and larval stages using a commercially available aqueous stabilisation reagent, RNAlater® eliminating the need for more cumbersome resources such as refrigerators, heaters and centrifuge equipment for immediate specimen processing. Adaptations to a general gDNA extraction method are described, that enables the acquisition of a gDNA extract (~50 μl, facilitating multiple molecular analyses of each sampled schistosome. The methodology provided PCR-quality mitochondrial and nuclear DNA from laboratory cercariae, miracidia and eggs that had been stored at up to 37°C for 2 weeks and at 4°C for 6 months and also from field collected samples. This present protocol provides significant epidemiological, ethical and practical advantages over existing sampling methods and has the potential to be transferred to studies on other organisms, especially where specimens are unable to be seen by the naked eye, are difficult to handle and need to be obtained from a field environment.

  2. Optofluidic ring resonator sensor for sensitive label-free detection of breast cancer antigen CA15-3 in human serum

    Science.gov (United States)

    Zhu, Hongying; Dale, Paul S.; Fan, Xudong

    2009-05-01

    Breast cancer is the most frequently diagnosed malignancy in women worldwide. Because of its great impact on society, a lot of research funding has been used to develop novel detection tools for aiding breast cancer diagnosis and prognosis. In this work, we demonstrated a simple, fast, and sensitive detection of circulating breast cancer biomarker CA15-3 with opto-fluidic ring resonator (OFRR) sensors. The OFRR sensor employs a thin-walled capillary with wall thickness less than 4 μm. The circular cross section of the capillary forms the optical ring resonator, in which the light circulates in the form of whispering gallery modes (WGMs). The capillary wall is thin enough that the evanescent field of the WGM extends into the capillary core and responds to refractive index changes in the capillary core or close to its interior surface. The WGM spectral position will change when the biomolecules bind to the surface, yielding quantitative and kinetic information about the biomolecule interaction. Here, the direct immunoassay method was employed for the detection of CA15-3 antigen without any signal amplification steps. The sensor performance in both PBS buffer and human serum were investigated, respectively. The experimental detection limit was 5 units/mL in PBS buffer and 30 units/mL for CA15-3 spiked in serum, both of which satisfied clinical diagnosis requirements. The potential use of the OFRR as the point-of-care device for breast cancer detection was tested by measuring the CA15-3 level in blood samples collected from stage IV breast cancer patients and the results were compared with standard clinical test.

  3. A sensitive label-free electrochemical immunosensor for detection of cytokeratin 19 fragment antigen 21-1 based on 3D graphene with gold nanopaticle modified electrode.

    Science.gov (United States)

    Zeng, Yan; Bao, Jing; Zhao, Yanan; Huo, Danqun; Chen, Mei; Yang, Mei; Fa, Huanbao; Hou, Changjun

    2018-02-01

    Previous studies have confirmed that cytokeratin 19 fragment antigen 21-1 (CYFRA 21-1) serves as a powerful biomarker in non-small cell lung cancer (NSCLC). Herein, we report for the first time a label-free electrochemical immunosensor for sensitive and selective detection of tumor marker CYFRA21-1. In this work, three-dimensional graphene @ gold nanoparticles (3D-G@Au) nanocomposite was modified on the glassy carbon electrode (GCE) surface to enhance the conductivity of immunosensor. The anti-CYFRA21-1 captured and fixed on the modified GCE through the cross-linking of chitosan (CS), glutaraldehyde (GA) and anti-CYFRA21-1. The differential pulse voltammetry (DPV) peak current change due to the specific interaction between anti-CYFRA21-1 and CYFRA21-1 on the modified electrode surface was utilized to detect CYFRA21-1. Under optimized conditions, the proposed electrochemical immunosensor was employed to detect CYFRA21-1 and exhibited a wide linear range of 0.25-800ngmL -1 and low detection limit of 100pgmL -1 (S/N = 3). Moreover, the recovery rates of serum samples were in the range from 95.2% to 108.7% and the developed immunosensor also shows a good correlation (less than 6.6%) with enzyme-linked immunosorbent assay (ELISA) in the detection of clinical serum samples. Therefore, it is expected that the proposed immunosensor based on a 3D-G@Au has great potential in clinical medical diagnosis of CYFRA21-1. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Comparison of detection of BVDV antigen in various types of tissue and fluid samples collected from persistently infected cattle

    Science.gov (United States)

    Aim. Bovine viral diarrhea viruses (BVDV) are economically important pathogens of cattle. Most new acute infections of BVDV are acquired from an animal persistently infected (PI) with BVDV. Surveillance programs typically rely on blood or skin biopsies for detection of PI cattle. PI animals have ...

  5. Improving dengue viral antigens detection in dengue patient serum specimens using a low pH glycine buffer treatment

    Directory of Open Access Journals (Sweden)

    Wen-Fan Shen

    2017-04-01

    Conclusion: Inclusion of a low-pH glycine buffer treatment step in the commercially available Ag-ELISA is crucial for clinical diagnosis and E-containing viral particles could be a valuable target for acute DENV diagnosis, similar to NS1 detection.

  6. New solid phase radioimmunoassay (CLB-RIA) for the detection of hepatitis-B antigen and antibody

    Energy Technology Data Exchange (ETDEWEB)

    Duimel, W J [Centraal Laboratorium van de Bloedtransfusiedienst, Amsterdam; Brummelhuis, H G.J.

    1975-07-01

    A new competitive solid phase radioimmunoassay (CLB-RIA) has been developed for the detection of HBAg and HBAb in human serum and plasma. In the assay, sheep antibodies to HBAg, covalently linked to an insoluble carrier, highly purified /sup 125/I labelled HBAg and the serum or plasma sample are incubated for 20 h at room temperature. After incubation, the bound and the free fraction of the tracer are separated by centrifugation. The presence of both HBAg and HBAb results in a decrease of the amount of bound tracer, when compared with a negative control serum. Differentiation between HBAg and HBAb requires the use of another type of radioimmunoassay. For this purpose a sandwich solid phase radioimmunoassay, for the detection of HBAb only, has been developed (CLB-AURIA). In this, assay-purified HBAg is covalently linked to an insoluble carrier. Using a mixture of both immunosorbents (insolubilized HBAg and HBAb), it is possible to detect and to distinguish HBAg and HBAb in one single solid phase radioimmunoassay (CLB-MIRIA). The influence of three parameters on the CLB-RIA, the incubation time, the amount of tracer and the effect of Tween-20 has been studied. The sensitivity of the described solid phase CLB-RIA for the detection of HBAg is comparable to that of other radioimmunoassays reported in literature; its specificity is very high.

  7. Circulating filarial antigen in the hydrocele fluid from individuals living in a bancroftian filariasis area - Recife, Brazil: detected by the monoclonal antibody Og4C3-assay

    Directory of Open Access Journals (Sweden)

    Abraham Rocha

    2004-02-01

    Full Text Available The purpose of this study was to examine the circulating filarial antigen (CFA detected by the monoclonal antibody (mAb Og4C3-ELISA in paired samples of serum and hydrocele fluid from 104 men with hydrocele, living in an endemic area of Wuchereria bancrofti. Nocturnal blood specimens were filtered and examined for microfilariae (MF and ultrasound was used in order to identify the presence of adult worms (the filaria dance sign - FDS in the lymphatic vessels of the scrotal area. Four groups were selected according to their parasitological status: group I - 71 MF- and FDS-; group II - 21 MF+ and FDS+; group III - 10 MF- and FDS+ and group IV- 2 MF+ and FDS-. CFA was identified simultaneously (fluid and serum in 11 (15.5%, 21 (100%, 3 (30%, and 1 (50% in groups I, II, III, and IV, respectively. In despite of high CFA+ level (antigen Og4C3 units/ml, the Geometrical Mean (GM = 2696 in the sera of these 36/104 paired samples, when compared to the hydrocele fluid, (GM = 1079, showed a very good correlation between the CFA level in the serum and CFA level in the fluid (r = 0.731. CFA level in the serum of the 23 microfilaremics (groups II and IV was extremely high (GM = 4189 and was correlated with MF density (r = 0.442. These findings report for the first time the potential alternative use of the hydrocele fluid to investigate CFA using the mAb Og4C3-ELISA.

  8. School Water, Sanitation, and Hygiene, Soil-Transmitted Helminths, and Schistosomes: National Mapping in Ethiopia.

    Directory of Open Access Journals (Sweden)

    Jack E T Grimes

    2016-03-01

    Full Text Available It is thought that improving water, sanitation, and hygiene (WASH might reduce the transmission of schistosomes and soil-transmitted helminths, owing to their life cycles. However, few large-scale studies have yet assessed the real extent of associations between WASH and these parasites.In the 2013-2014 Ethiopian national mapping of infections with these parasites, school WASH was assessed alongside infection intensity in children, mostly between 10 and 15 years of age. Scores were constructed reflecting exposure to schistosomes arising from water collection for schools, from freshwater sources, and the adequacy of school sanitation and hygiene facilities. Kendall's τb was used to test the WASH scores against the school-level arithmetic mean intensity of infection with each parasite, in schools with at least one child positive for the parasite in question. WASH and parasitology data were available for 1,645 schools. More frequent collection of water for schools, from open freshwater sources was associated with statistically significantly higher Schistosoma mansoni infection intensity (Kendall's τb = 0.097, 95% confidence interval, CI: 0.011 to 0.18, better sanitation was associated with significantly lower Ascaris lumbricoides intensity (Kendall's τb = -0.067, 95% CI: -0.11 to -0.023 and borderline significant lower hookworm intensity (Kendall's τb = -0.039, 95% CI: -0.090 to 0.012, P = 0.067, and better hygiene was associated with significantly lower hookworm intensity (Kendall's τb = -0.076, 95% CI: -0.13 to -0.020. However, no significant differences were observed when comparing sanitation and infection with S. mansoni or Trichuris trichiura, or hygiene and infection with A. lumbricoides or T. trichiura.Improving school WASH may reduce transmission of these parasites. However, different forms of WASH appear to have different effects on infection with the various parasites, with our analysis finding the strongest associations between

  9. School Water, Sanitation, and Hygiene, Soil-Transmitted Helminths, and Schistosomes: National Mapping in Ethiopia.

    Science.gov (United States)

    Grimes, Jack E T; Tadesse, Gemechu; Mekete, Kalkidan; Wuletaw, Yonas; Gebretsadik, Abeba; French, Michael D; Harrison, Wendy E; Drake, Lesley J; Gardiner, Iain A; Yard, Elodie; Templeton, Michael R

    2016-03-01

    It is thought that improving water, sanitation, and hygiene (WASH) might reduce the transmission of schistosomes and soil-transmitted helminths, owing to their life cycles. However, few large-scale studies have yet assessed the real extent of associations between WASH and these parasites. In the 2013-2014 Ethiopian national mapping of infections with these parasites, school WASH was assessed alongside infection intensity in children, mostly between 10 and 15 years of age. Scores were constructed reflecting exposure to schistosomes arising from water collection for schools, from freshwater sources, and the adequacy of school sanitation and hygiene facilities. Kendall's τb was used to test the WASH scores against the school-level arithmetic mean intensity of infection with each parasite, in schools with at least one child positive for the parasite in question. WASH and parasitology data were available for 1,645 schools. More frequent collection of water for schools, from open freshwater sources was associated with statistically significantly higher Schistosoma mansoni infection intensity (Kendall's τb = 0.097, 95% confidence interval, CI: 0.011 to 0.18), better sanitation was associated with significantly lower Ascaris lumbricoides intensity (Kendall's τb = -0.067, 95% CI: -0.11 to -0.023) and borderline significant lower hookworm intensity (Kendall's τb = -0.039, 95% CI: -0.090 to 0.012, P = 0.067), and better hygiene was associated with significantly lower hookworm intensity (Kendall's τb = -0.076, 95% CI: -0.13 to -0.020). However, no significant differences were observed when comparing sanitation and infection with S. mansoni or Trichuris trichiura, or hygiene and infection with A. lumbricoides or T. trichiura. Improving school WASH may reduce transmission of these parasites. However, different forms of WASH appear to have different effects on infection with the various parasites, with our analysis finding the strongest associations between water and S

  10. Rigidity and resistance of larval- and adult schistosomes-medium interface

    Energy Technology Data Exchange (ETDEWEB)

    Migliardo, Federica, E-mail: fmigliardo@unime.it [Department of Physics and Earth Sciences, University of Messina, 98166 Messina (Italy); Tallima, Hatem; El Ridi, Rashika [Zoology Department, Faculty of Science, Cairo University, Cairo 12613 (Egypt)

    2014-03-28

    Graphical abstract: - Highlights: • Schistosoma larvae and worms are studied by neutron scattering. • Measurements on larvae were repeated after one day and by increasing temperature. • The flexibility properties of larvae and adult parasites are compared. • The parasite rigidity is related to their resistance to the hostile environment. • Insight into the parasite defense mechanisms to the immune system attack is achieved. - Abstract: Schistosomiasis is second only to malaria in prevalence and severity, and is still a major health problem in many tropical countries worldwide with about 200–300 million cases and with more than 800 million people at risk of infection. Based on these data, the World Health Organization recommends fostering research efforts for understanding at any level the mechanisms of the infection and then decreasing the social and economical impact of schistosomiasis. A key role is played by the parasite apical lipid membrane, which is entirely impervious to the surrounding elements of the immune system. We have previously demonstrated that the interaction between schistosomes and surrounding medium is governed by a parasite surface membrane sphingomyelin-based hydrogen barrier. In the present article, the elastic contribution to the total motion as a function of the exchanged wave-vector Q and the mean square displacement values for Schistosoma mansoni larvae and worms and Schistosomahaematobium worms have been evaluated by quasi elastic neutron scattering (QENS). The results point out that S. mansoni larvae show a smaller mean square displacement in comparison to S. mansoni and S. haematobium worms. These values increased by repeating the measurements after one day. These differences, which are analogous to those observed for the diffusion coefficient we previously evaluated, are interpreted in terms of rigidity of the parasite-medium interaction. S. mansoni larvae are the most rigid systems, while S. haematobium worms are the most

  11. DETECTION OF HUMAN ANTI-ZIKA VIRUS IgG BY ELISA USING AN ANTIGEN FROM in vitro INFECTED VERO CELLS: PRELIMINARY RESULTS

    Directory of Open Access Journals (Sweden)

    Laura Masami SUMITA

    Full Text Available SUMMARY Zika virus (ZKV infection is a huge public health problem in Brazil because of the increased incidence of microcephaly in neonates from infected mothers. Detection of specific IgG antibodies in maternal serum samples constitutes an important approach for diagnosing ZKV infection and evaluating its relationship with neonatal microcephaly. However, as there is no serological test produced in Brazil to detect IgM and IgG antibodies against ZKV, we sought to examine specific IgG in serum samples from patients or suspected mothers to detect previous infection and to test for specificity with regard to flaviviral infections occurring in the same area. Brazilian Zika virus native antigens were obtained from infected Vero cell layers or free virions in the culture medium and then used in ELISA. We tested sera from eight ZKV RNA-diagnosed infected patients (ZKVR, seven neonates with microcephaly and their mothers after delivery (MM, 140 dengue virus IgM-positive (DM and IgG (DG-positive patients, and 100 yellow fever (YF-vaccinated patients. According to the ELISA, ZKVR samples were mostly positive (7/8, and all the MM serum samples were positive for ZKV IgG (7/7. In contrast, cross-reactions for dengue or yellow fever-vaccinated patients were observed, including DM (48/95, DG (10/45 or YF (3/100 serum samples; however, these cross-reactions exhibited low antigen avidity so that 6 M urea largely removed this cross-reactivity, with only a few cross-reacting samples remaining (8/140. ELISA based on extracted virions was much more specific, with all ZKVR (8/8 and MM sera being positive for ZKV IgG (7/7 and only borderline cross-reactivity found for DM (6/95, DG (3/45 or YF (4/100-vaccinated serum samples. This technique (ELISA can identify specific IgG in ZKV-infected patients and may be helpful in diagnosing congenital infetions after maternal RNA virus clearance or in epidemiological studies.

  12. Rapid, highly sensitive detection of herpes simplex virus-1 using multiple antigenic peptide-coated superparamagnetic beads.

    Science.gov (United States)

    Ran, Ying-Fen; Fields, Conor; Muzard, Julien; Liauchuk, Viktoryia; Carr, Michael; Hall, William; Lee, Gil U

    2014-12-07

    A sensitive, rapid, and label free magnetic bead aggregation (MBA) assay has been developed that employs superparamagnetic (SPM) beads to capture, purify, and detect model proteins and the herpes simplex virus (HSV). The MBA assay is based on monitoring the aggregation state of a population of SPM beads using light scattering of individual aggregates. A biotin-streptavidin MBA assay had a femtomolar (fM) level sensitivity for analysis times less than 10 minutes, but the response of the assay becomes nonlinear at high analyte concentrations. A MBA assay for the detection of HSV-1 based on a novel peptide probe resulted in the selective detection of the virus at concentrations as low as 200 viral particles (vp) per mL in less than 30 min. We define the parameters that determine the sensitivity and response of the MBA assay, and the mechanism of enhanced sensitivity of the assay for HSV. The speed, relatively low cost, and ease of application of the MBA assay promise to make it useful for the identification of viral load in resource-limited and point-of-care settings where molecular diagnostics cannot be easily implemented.

  13. Validation of a urine circulating cathodic antigen cassette test for detection of Schistosoma haematobiumin uMkhanyakude district of South Africa.

    Science.gov (United States)

    Rubaba, O; Chimbari, M J; Soko, W; Manyangadze, T; Mukaratirwa, S

    2018-06-01

    Circulating cathodic antigen (CCA) tests for schistosomiasis are fast and less complicated allowing making them good candidates for routine qualitative screening for schistosomiasis at point of care. The urine-CCA has been evaluated for detection of S. mansoni with promising results. Its specificity and consistency in detecting S. haematobium infection in different endemic regions has been variable. This study validated a rapid urine-CCA cassette test for qualitative detection of S. haematobium infection in an S. haematobium endemic area with low S. mansoni prevalence. Microscopic examination for the standard urine filtration technique was used to validate the commercially available urine-CCA cassette test (rapid medical diagnostics ® ). The validation was done in a sample of primary school pupils (n = 420) aged 10-15 years in schools in the Jozini Municipality, KZN. There was a relationship between infection intensity and a positive urine-CCA test. Using the urine filtration method as the gold standard, the prevalence for S. haematobium was 40%, the accuracy of the CCA kit was 54.8%, sensitivity was 68.1% while the specificity was 45.8%. The positive predictive value was 45.82% while the negative predictive value was 68.05%. Both the urine filtration and the urine-CCA methods detected heavy (≥50 eggs/10 mL urine) and light infections at statistically significant levels. The overall accuracy, sensitivity and specificity of the urine-CCA cassette test were low. The urine-CCA cassette test performed much better for heavy infections than low infections (p < 0.05) implying that the kit may not be suitable for low endemic areas. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Incidental detection of prostate-specific antigen-negative metastatic prostate cancer initially presented with solitary pulmonary nodule on fluorodeoxyglucose positron emission tomography/computed tomography

    International Nuclear Information System (INIS)

    Erdogan, Ezgi Basak; Buyukpinarbasili, Nur; Ziyade, Sedat; Akman, Tolga; Turk, Haci Mehmet; Aydin, Mehmet

    2005-01-01

    A 71-year-old male patient with solitary pulmonary nodule underwent fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) showing slightly increased FDG uptake in this nodule. In addition, PET/CT detected hypermetabolic sclerotic bone lesions in the right second rib and 7 th thoracic vertebrae, which were interpreted as possible metastases, and mildly increased FDG uptake in the prostate gland highly suspicious of malignancy. The patient's prostate-specific antigen (PSA) level was within normal range (3.8 ng/dL). The histopathological examination of the lung nodule and right second rib lesion proved metastases from prostate cancer, then the prostate biopsy-confirmed prostate adenocarcinoma. The unique feature of this case is to emphasize the importance of performing PET/CT for solitary pulmonary nodule in detecting PSA-negative metastatic prostate cancer. This case indicated that it should be kept in mind that, even if the PSA is negative, a lung metastasis of prostate cancer may be an underlying cause in patients evaluated for solitary pulmonary nodule by FDG PET/CT

  15. Detection of NP, N3 and N7 antibodies to avian influenza virus by indirect ELISA using yeast-expressed antigens

    Directory of Open Access Journals (Sweden)

    Ammayappan Arun

    2009-10-01

    Full Text Available Abstract Background Avian influenza viruses, belonging to the family Orthomyxoviridae, possess distinct combinations of hemagglutinin (H and the neuraminidase (N surface glycoproteins. Typing of both H and N antigens is essential for the epidemiological and surveillance studies. Therefore, it is important to find a rapid, sensitive, and specific method for their assay, and ELISA can be useful for this purpose, by using recombinant proteins. Results The nucleoprotein (NP and truncated neuraminidase subtype 3 and 7 of avian influenza virus (AIV were expressed in Saccharomyces cerevisiae and used to develop an indirect enzyme-linked immunosorbent assay for antibody detection. The developed assays were evaluated with a panel of 64 chicken serum samples. The performance of NP-ELISA was compared with the commercially available ProFlok® AIV ELISA kit. The results showed comparable agreement and sensitivity between the two tests, indicating that NP-ELISA assay can be used for screening the influenza type A antibody in AIV infected birds. The N3 and N7- ELISAs also reacted specifically to their type specific sera and did not exhibit any cross-reaction with heterologous neuraminidase subtype specific sera. Conclusion The study demonstrates the expression of the NP, N3, and N7 proteins of AIV in yeast (S. cerevisiae and their application in developing an indirect ELISA for detecting NP, N3 and N7 antibodies from AIV-infected chicken sera. The described indirect ELISAs are rapid, sensitive, specific and can be used as promising tests during serological surveillance.

  16. Dynamics of paediatric urogenital schistosome infection, morbidity and treatment: a longitudinal study among preschool children in Zimbabwe.

    Science.gov (United States)

    Osakunor, Derick Nii Mensah; Mduluza, Takafira; Midzi, Nicholas; Chase-Topping, Margo; Mutsaka-Makuvaza, Masceline Jenipher; Chimponda, Theresa; Eyoh, Enwono; Mduluza, Tariro; Pfavayi, Lorraine Tsitsi; Wami, Welcome Mkululi; Amanfo, Seth Appiah; Murray, Janice; Tshuma, Clement; Woolhouse, Mark Edward John; Mutapi, Francisca

    2018-01-01

    Recent research has shown that in schistosome-endemic areas preschool-aged children (PSAC), that is, ≤5 years, are at risk of infection. However, there exists a knowledge gap on the dynamics of infection and morbidity in this age group. In this study, we determined the incidence and dynamics of the first urogenital schistosome infections, morbidity and treatment in PSAC. Children (6 months to 5 years) were recruited and followed up for 12 months. Baseline demographics, anthropometric and parasitology data were collected from 1502 children. Urinary morbidity was assessed by haematuria and growth-related morbidity was assessed using standard WHO anthropometric indices. Children negative for Schistosoma haematobium infection were followed up quarterly to determine infection and morbidity incidence. At baseline, the prevalence of S haematobium infection and microhaematuria was 8.5% and 8.6%, respectively. Based on different anthropometric indices, 2.2%-8.2% of children were malnourished, 10.1% underweight and 18.0% stunted. The fraction of morbidity attributable to schistosome infection was 92% for microhaematuria, 38% for stunting and malnutrition at 9%-34%, depending on indices used. S haematobium -positive children were at greater odds of presenting with microhaematuria (adjusted OR (AOR)=25.6; 95% CI 14.5 to 45.1) and stunting (AOR=1.7; 95% CI 1.1 to 2.7). Annual incidence of S haematobium infection and microhaematuria was 17.4% and 20.4%, respectively. Microhaematuria occurred within 3 months of first infection and resolved in a significant number of children, 12 weeks post-praziquantel treatment, from 42.3% to 10.3%; P<0.001. We demonstrated for the first time the incidence of schistosome infection in PSAC, along with microhaematuria, which appears within 3 months of first infection and resolves after praziquantel treatment. A proportion of stunting and malnutrition is attributable to S haematobium infection. The study adds scientific evidence to the calls for

  17. Improved Detection of Invasive Pulmonary Aspergillosis Arising during Leukemia Treatment Using a Panel of Host Response Proteins and Fungal Antigens.

    Directory of Open Access Journals (Sweden)

    Allan R Brasier

    Full Text Available Invasive pulmonary aspergillosis (IPA is an opportunistic fungal infection in patients undergoing chemotherapy for hematological malignancy, hematopoietic stem cell transplant, or other forms of immunosuppression. In this group, Aspergillus infections account for the majority of deaths due to mold pathogens. Although early detection is associated with improved outcomes, current diagnostic regimens lack sensitivity and specificity. Patients undergoing chemotherapy, stem cell transplantation and lung transplantation were enrolled in a multi-site prospective observational trial. Proven and probable IPA cases and matched controls were subjected to discovery proteomics analyses using a biofluid analysis platform, fractionating plasma into reproducible protein and peptide pools. From 556 spots identified by 2D gel electrophoresis, 66 differentially expressed post-translationally modified plasma proteins were identified in the leukemic subgroup only. This protein group was rich in complement components, acute-phase reactants and coagulation factors. Low molecular weight peptides corresponding to abundant plasma proteins were identified. A candidate marker panel of host response (9 plasma proteins, 4 peptides, fungal polysaccharides (galactomannan, and cell wall components (β-D glucan were selected by statistical filtering for patients with leukemia as a primary underlying diagnosis. Quantitative measurements were developed to qualify the differential expression of the candidate host response proteins using selective reaction monitoring mass spectrometry assays, and then applied to a separate cohort of 57 patients with leukemia. In this verification cohort, a machine learning ensemble-based algorithm, generalized pathseeker (GPS produced a greater case classification accuracy than galactomannan (GM or host proteins alone. In conclusion, Integration of host response proteins with GM improves the diagnostic detection of probable IPA in patients

  18. Binding of hydrophobic antigens to surfaces

    DEFF Research Database (Denmark)

    2017-01-01

    A first aspect of the present invention is a method of detecting antibodies comprising the steps of: i) providing a first group of beads comprising a surface modified with C1-C10 alkyl groups comprising amine, ammonium, ether and/or hydroxyl groups, ii) contacting said first group of beads......-antigen-antibody conjugates, and v) detecting said bead-antigen-antibody conjugates. Further aspects include an antibody detection kit, a bead-antigen conjugate and a composition comprising at least two different groups of bead-antigen-conjugates....

  19. Clinical-epidemiologic profile of the schistosomal myeloradiculopathy in Pernambuco, Brazil

    Directory of Open Access Journals (Sweden)

    Karina Conceição GM de Araújo

    2010-07-01

    Full Text Available This was a retrospective descriptive study on a series of cases of schistosomal myeloradiculopathy (SMR and the aim was to investigate the incidence of this disease and its clinical and epidemiological characteristics in cases diagnosed at three healthcare units in Pernambuco, Brazil between 1994-2006. The data were collected by reviewing the medical records from both the neurological and paediatric outpatient clinics and wards of the Hospital Clinics, Hospital of the Restoration and Pernambuco Mother and Child Institute. To gather the data, a spinal cord schistosomiasis evaluation protocol was used. The diagnoses were based on positive epidemiological evidence of schistosomiasis, clinical findings and laboratory tests (stool parasitological examination or rectal biopsies, magnetic resonance imaging findings and cerebrospinal fluid investigations. A total of 139 cases aged between 2-83 years were found. The most important determinants of SMR were male sex (66.2%, contact with fresh water (91%, origin in endemic regions (39.5%, lower-limb muscle weakness (100%, sensory level at the lower thoracic medulla (40.3%, myeloradicular form (76% and presence of eggs in the stool parasitological examination (48%. This sample indicates the need for intervention policies guided by diagnostic standardization, thereby avoiding disease under-notification.

  20. Haematological and biochemical characteristics of the splenic effluent blood in schistosomal patients undergoing splenectomy

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    Andy Petroianu

    Full Text Available OBJECTIVE: To assess hematological and biochemical features of splenic effluent blood and their influence on the rise of hematological values after splenectomy. METHODS: we studied 20 patients undergoing surgical treatment for schistosomatic portal hypertension. We collected blood samples for CBC, coagulation, bilirubin and albumin in the splenic vein (perioperative and peripheral blood (immediately pre and postoperative periods. RESULTS: the splenic blood showed higher values of red blood cells, hemoglobin, hematocrit, platelet count, total leukocytes, neutrophils, lymphocytes, monocytes, eosinophils and basophils, as well as reduction of laboratory coagulation parameters in relation to peripheral blood collected preoperatively. In the postoperative peripheral blood there was an increase in the overall leukocytes and in their neutrophil component, and decreased levels of basophils, eosinophils and lymphocytes. The other postoperative variables of complete blood count and coagulation tests were not different compared with the splenic blood. The albumin values were lower postoperatively when compared to preoperative and splenic blood. There were higher values of direct bilirubin in the postoperative period when compared with the preoperative and splenic blood. Postoperative indirect bilirubin was lower compared to its value in the splenic blood. CONCLUSION: hematological and biochemical values of splenic effluent blood are higher than those found in peripheral blood in the presence of schistosomal splenomegaly. However, the splenic blood effluent is not sufficient to raise the blood levels found after splenectomy.

  1. Three-dimensional structure of a schistosome serpin revealing an unusual configuration of the helical subdomain

    Energy Technology Data Exchange (ETDEWEB)

    Granzin, Joachim [Institute of Complex Systems, ICS-6: Structural Biochemistry, Forschungszentrum Jülich, 52425 Jülich (Germany); Huang, Ying; Topbas, Celalettin [Department of Cell Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195 (United States); Huang, Wenying [Department of Cancer Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195 (United States); Wu, Zhiping [Department of Cell Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195 (United States); Misra, Saurav [Department of Molecular Cardiology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195 (United States); Hazen, Stanley L. [Department of Cell Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195 (United States); Blanton, Ronald E. [Department of Infectious Diseases, Case Western Reserve University, Cleveland, OH 44190 (United States); Lee, Xavier [Department of Cell Biology, Lerner Research Institute, Cleveland Clinic, Cleveland, OH 44195 (United States); Weiergräber, Oliver H., E-mail: o.h.weiergraeber@fz-juelich.de [Institute of Complex Systems, ICS-6: Structural Biochemistry, Forschungszentrum Jülich, 52425 Jülich (Germany)

    2012-06-01

    The crystal structure of ShSPI, a serpin from the blood fluke S. haematobium, reveals some peculiar features of the helical subdomain which have not been observed previously in the serpin superfamily. Parasitic organisms are constantly challenged by the defence mechanisms of their respective hosts, which often depend on serine protease activities. Consequently, protease inhibitors such as those belonging to the serpin superfamily have emerged as protective elements that support the survival of the parasites. This report describes the crystal structure of ShSPI, a serpin from the trematode Schistosoma haematobium. The protein is exposed on the surface of invading cercaria as well as of adult worms, suggesting its involvement in the parasite–host interaction. While generally conforming to the well established serpin fold, the structure reveals several distinctive features, mostly concerning the helical subdomain of the protein. It is proposed that these peculiarities are related to the unique biological properties of a small serpin subfamily which is conserved among pathogenic schistosomes.

  2. Genetic dissimilarity between mates, but not male heterozygosity, influences divorce in schistosomes.

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    Sophie Beltran

    Full Text Available BACKGROUND: Correlational studies strongly suggest that both genetic similarity and heterozygosity can influence female mate choice. However, the influence of each variable has usually been tested independently, although similarity and heterozygosity might be correlated. We experimentally determined the relative influence of genetic similarity and heterozygosity in divorce and re-mating in the monogamous endoparasite Schistosoma mansoni. METHODOLOGY/PRINCIPAL FINDINGS: We performed sequential infections of vertebrate hosts with controlled larval populations of parasites, where sex and individual genetic diversity and similarity were predetermined before infection. Divorce rate increased significantly when females were given the opportunity to increase genetic dissimilarity through re-mating with a new partner, independently of the intensity of male-male competition. We found however no evidence for females attempting to maximize the level of heterozygosity of their reproductive partner through divorce. CONCLUSIONS/SIGNIFICANCE: Female preference for genetically dissimilar males should result in more heterozygous offspring. Because genetic heterozygosity might partly determine the ability of parasites to counter host resistance, adaptive divorce could be an important factor in the evolutionary arms race between schistosomes and their hosts.

  3. Portal blood flow volume measurement in schistosomal patients: evaluation of Doppler ultrasonography reproducibility

    International Nuclear Information System (INIS)

    Leao, Alberto Ribeiro de Souza; Santos, Jose Eduardo Mourao; Moulin, Danilo Sales; Shigueoka, David Carlos; D'Ippolito, Giuseppe; Colleoni, Ramiro

    2008-01-01

    Objective: To evaluate the reproducibility of Doppler ultrasonography in the measurement of portal blood flow volume in schistosomal patients. Materials and methods: Prospective, transversal, observational and self-paired study evaluating 21 patients with hepatosplenic schistosomiasis submitted to Doppler ultrasonography performed by three independent observers for measurement of portal blood flow. Pairwise interobserver agreement was calculated by means of the intraclass correlation coefficient, paired t-test and Pearson's correlation coefficient. Results: Interobserver agreement was excellent. Intraclass correlation ranged from 80.6% to 93.0% (IC at 95% [65.3% ; 95.8%]), with the Pearson's correlation coefficient ranging between 81.6% and 92.7% with no statistically significant interobserver difference regarding the mean portal blood flow volume measured by Doppler ultrasonography (p = 0.954 / 0.758 / 0.749). Conclusion: Doppler ultrasonography has demonstrated to be a reliable method for measuring the portal blood flow volume in patients with portal hypertension secondary to schistosomiasis, with a good interobserver agreement. (author)

  4. The susceptibility of Marisa cornuarietis, a predator of schistosome bearing snails, to N-tritylmorpholine.

    Science.gov (United States)

    Meier-Brook, C; Tjhen, K Y

    1977-03-01

    Introduction of the ampullariid snail, Marisa cornuarietis (L.), into water treated with molluscicides, in order to secure the success of chemical control of schistosome host snails, is promising. Adult Marisa can be introduced only two days after treating water of pH less than or equal to 7-9 with N-tritylmorpholine (= FresconR Shell) at a concentration of 0-03 ppm. There is considerable variation in the susceptibility of different strains: the LT50 in a concentration of 0-03 ppm Frescon at 25 degrees C was about 27-3 hours for a Puerto Rican and 44-6 hours for a Floridan strain, both 52 weeks old. At sexual maturity, i.e. approximately 18 weeks at 25 degrees C, the LT50 for the Floridan strain was approximately 31-8 hours; experiments with a hybrid stock of the two strains had an LT50 of 30-0 hours. Younger snails were significantly more susceptible to the molluscicide, and eggs were approximately four times more resistant than adults; this agrees with findings by previous authors for other snail species. In the case of the accidental uncontrolled spread of Marisa to cultivated areas it is suggested that a concentration of 0-03 Frescon is applied for at least four days.

  5. Comparison of four species of snails as potential decoys to intercept schistosome miracidia.

    Science.gov (United States)

    Laracuente, A; Brown, R A; Jobin, W

    1979-01-01

    Preliminary studies have shown that various species of aquatic snails may be used as decoys or "sponges" to intercept schistosome miracidia, thereby preventing the miracidia from reaching the snails which normally serve as their intermediate host. In this study, four species of snails were evaluated as candidate decoys for field trials: Marisa cornuarietis, Pomacea australis, Helisoma caribaeum, and Tarebia granifera. In the laboratory all four species caused considerable reductions in the proportion of Biomphalaria glabrata infected by miracidia of Schistosoma mansoni. The most effective decoys were M. cornuarietis and H. caribaeum, both of which caused experimental infection levels of 90% to decrease to 25% when five decoy snails were present for each target snail. When ten decoy snails were present for each target snail, the proportion infected decreased to 1%. M. cornuarietis was chosen as the candidate for field trials because it was found more frequently in Puerto Rico than was H. caribaeum. Initial field trials in two ponds showed that M. cornuarietis blocked infections at a ratio of 6 decoys to 1 target snail, confirming the laboratory results. Further studies in flowing water are needed before the technique can be generally evaluated in an endemic area.

  6. Portal blood flow volume measurement in schistosomal patients: evaluation of Doppler ultrasonography reproducibility

    Energy Technology Data Exchange (ETDEWEB)

    Leao, Alberto Ribeiro de Souza; Santos, Jose Eduardo Mourao; Moulin, Danilo Sales; Shigueoka, David Carlos; D' Ippolito, Giuseppe [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Escola Paulista de Medicina. Dept. de Diagnostico por Imagem]. E-mail: ar.leao@uol.com.br; Colleoni, Ramiro [Universidade Federal de Sao Paulo (UNIFESP/EPM), SP (Brazil). Escola Paulista de Medicina. Dept. de Gastroenterologia

    2008-09-15

    Objective: To evaluate the reproducibility of Doppler ultrasonography in the measurement of portal blood flow volume in schistosomal patients. Materials and methods: Prospective, transversal, observational and self-paired study evaluating 21 patients with hepatosplenic schistosomiasis submitted to Doppler ultrasonography performed by three independent observers for measurement of portal blood flow. Pairwise interobserver agreement was calculated by means of the intraclass correlation coefficient, paired t-test and Pearson's correlation coefficient. Results: Interobserver agreement was excellent. Intraclass correlation ranged from 80.6% to 93.0% (IC at 95% [65.3% ; 95.8%]), with the Pearson's correlation coefficient ranging between 81.6% and 92.7% with no statistically significant interobserver difference regarding the mean portal blood flow volume measured by Doppler ultrasonography (p = 0.954 / 0.758 / 0.749). Conclusion: Doppler ultrasonography has demonstrated to be a reliable method for measuring the portal blood flow volume in patients with portal hypertension secondary to schistosomiasis, with a good interobserver agreement. (author)

  7. Pharmacological profiling an abundantly expressed schistosome serotonergic GPCR identifies nuciferine as a potent antagonist

    Directory of Open Access Journals (Sweden)

    John D. Chan

    2016-12-01

    Full Text Available 5-hydroxytryptamine (5-HT is a key regulator of muscle contraction in parasitic flatworms. In Schistosoma mansoni, the myoexcitatory action of 5-HT is effected through activation of a serotonergic GPCR (Sm.5HTRL, prioritizing pharmacological characterization of this target for anthelmintic drug discovery. Here, we have examined the effects of several aporphine alkaloids on the signaling activity of a heterologously expressed Sm.5HTRL construct using a cAMP biosensor assay. Four structurally related natural products – nuciferine, D-glaucine, boldine and bulbocapnine – were demonstrated to block Sm.5HTRL evoked cAMP generation with the potency of GPCR blockade correlating well with the ability of each drug to inhibit contractility of schistosomule larvae. Nuciferine was also effective at inhibiting both basal and 5-HT evoked motility of adult schistosomes. These data advance our understanding of structure-affinity relationships at Sm.5HTRL, and demonstrate the effectiveness of Sm.5HTRL antagonists as hypomotility-evoking drugs across different parasite life cycle stages.

  8. Real time detection of antibody-antigen interaction using a laser scanning confocal imaging-surface plasmon resonance system

    International Nuclear Information System (INIS)

    Zhang Hong-Yan; Yang Li-Quan; Ning Ting-Yin; Liu Wei-Min; Sun Jia-Yu; Wang Peng-Fei; Meng Lan; Nie Jia-Cai

    2012-01-01

    A laser scanning confocal imaging-surface plasmon resonance (LSCI-SPR) instrument integrated with a wavelength-dependent surface plasmon resonance (SPR) sensor and a laser scanning confocal microscopy (LSCM) is built to detect the bonding process of human IgG and fluorescent-labeled affinity purified antibodies in real time. The shifts of resonant wavelength at different reaction time stages are obtained by SPR, corresponding well with the changes of the fluorescence intensity collected by using LSCM. The instrument shows the merits of the combination and complementation of the SPR and LSCM, with such advantages as quantificational analysis, high spatial resolution and real time monitor, which are of great importance for practical applications in biosensor and life science. (general)

  9. Expression of Toll-like receptors and their detection of nuclear self-antigen leading to immune activation in JSLE.

    Science.gov (United States)

    Midgley, Angela; Thorbinson, Colin; Beresford, Michael W

    2012-05-01

    Toll-like receptors (TLRs) essential in the functioning of the immune system have been implicated in the development of autoimmunity. TLR3, 7, 8 and 9 are capable of recognizing nucleic autoantigens typical of SLE. Their expression correlates positively with disease activity in adult-onset SLE. This study aimed to determine the role of TLRs in JSLE and whether apoptotic neutrophils are a source of nuclear autoantigen being detected through TLR3, 7, 8 and 9, leading to an inflammatory response. TLR3, 7, 8 and 9 mRNA and protein expression were measured in peripheral blood mononuclear cells (PBMCs) in JSLE patients compared with JIA and non-inflammatory controls. Activation of the TLRs by JSLE serum-induced apoptotic neutrophils was detected by measuring IFN-α mRNA and protein expression, and confirmed using myeloid differentiation factor 88 (MyD88) and TIR domain-containing adapter-inducing IFN-β (TRIF) inhibitors. JSLE patients have increased TLR3, 8 and 9 mRNA and protein expression compared with controls (P < 0.05). Incubation of PBMCs with apoptotic neutrophils demonstrated a dose-response relationship for IFN-α mRNA expression. Inhibition of TLR signalling by blocking MyD88 and TRIF signalling decreased IFN-α mRNA expression in PBMCs incubated with apoptotic neutrophils (P < 0.05). This study demonstrated significantly increased TLR expression in JSLE compared with controls. Our data indicate that apoptotic neutrophils trigger TLR activation through their presentation of autoantigens. The role of TLRs in this inflammatory response was demonstrated by a dose-response relationship to apoptotic neutrophil concentration and confirmed by a decrease in IFN-α production after inhibition of TLR signalling.

  10. Immunity to tumour antigens.

    Science.gov (United States)

    Li, Geng; Ali, Selman A; McArdle, Stephanie E B; Mian, Shahid; Ahmad, Murrium; Miles, Amanda; Rees, Robert C

    2005-01-01

    During the last decade, a large number of human tumour antigens have been identified. These antigens are classified as tumour-specific shared antigens, tissue-specific differentiation antigens, overexpressed antigens, tumour antigens resulting from mutations, viral antigens and fusion proteins. Antigens recognised by effectors of immune system are potential targets for antigen-specific cancer immunotherapy. However, most tumour antigens are self-proteins and are generally of low immunogenicity and the immune response elicited towards these tumour antigens is not always effective. Strategies to induce and enhance the tumour antigen-specific response are needed. This review will summarise the approaches to discovery of tumour antigens, the current status of tumour antigens, and their potential application to cancer treatment.

  11. Improvements on an ELISA to detect trypanosomal antigens and its use as a monitoring tool in tsetse and trypanosomosis control programmes

    International Nuclear Information System (INIS)

    Dwinger, R.H.; Rebeski, D.; Winger, E.

    1997-01-01

    Monoclonal antibodies directed at epitopes of Trypanosoma brucei, T. congolense and T. vivax have been used to capture and detect trypanosomal antigens in bovine blood samples using an enzyme-linked immunosorbent assay (ELISA) developed elsewhere. The test has been transformed in a ready-to-use kit format for distribution among a network of 15 African research institutes. The specificity of the test was assessed under experimental and field conditions and found to be 96% (± 2%) for T. brucei, 99.5% (±1%) for T. congolense and 99% (±1%) for T. vivax. Following a validation period under field conditions, adjustments were made to the protocol to increase the sensitivity of the ELISA and to improve the suitability of the test for laboratory use under African conditions. Presently the ag-ELISA is being applied in conjunction with conventional parasitological techniques such as the buffy coat technique (BCT) to monitor progress in various tsetse and trypanosomosis control programmes and in a tsetse eradication effort in the United Republic of Tanzania, on the island of Zanzibar. The two tests complement each other, since infections not detected by one test may be detected by the other. In general, the serological test tends to produce more false negatives during subacute infections, while the parasitological techniques tend to produce more false negatives during chronic infections. Since the sensitivity of the ELISA is not optimal, research efforts at the FAO/IAEA Agriculture and Biotechnology Laboratory will be focused on improving this aspect. However, these efforts are severely hampered by the lack of a diagnostic test that can be used as a ''gold standard''. The use of the polymerase chain reaction for verifying doubtful test results and as a possible candidate for a ''gold standard'' to diagnose trypanosomosis are discussed. Finally, future plans are outlined to initiate the use of geographical information systems to assess the impact of tsetse control and

  12. A novel method for sensitive, low-cost and portable detection of hepatitis B surface antigen using a personal glucose meter.

    Science.gov (United States)

    Taebi, Saeed; Keyhanfar, Mehrnaz; Noorbakhsh, Abdollah

    2018-04-12

    Hepatitis B virus (HBV) infection is the major public health problem leading cause of death worldwide. The most important diagnostic marker for this infection is hepatitis B surface antigen (HBsAg). In this study, a novel, inexpensive, portable and sensitive ELISA method was designed and investigated for diagnosis of HBsAg based on the functionalized Fe 3 O 4 and Al 2 O 3 nanoparticles, with the strategy for detecting the concentration of glucose using a cheap and accessible personal glucose meter (PGM). The ELISA system was constructed using hepatitis B antibody against HBsAg immobilized on streptavidin coated magnetic iron oxide particles (S-Fe 3 O 4 ) as the capture antibody (Ab 1 ). In addition, another hepatitis B antibody against different epitope of HBsAg (Ab 2 ) and glucoamylase both were immobilized on Al 2 O 3 nanoparticles. After formation of the sandwich immune complex between Ab 1 and Ab 2 immobilized on S-Fe 3 O 4 and Al 2 O 3 NPs, respectively, through HBsAg, starch was converted into glucose using glucoamylase. Then, the glucose concentration was measured using PGM. The concentration of HBsAg was calculated based on the linear relation between the concentrations of HBsAg and glucose. Under optimal conditions, this assay showed detection limit values of 0.3 to 0.4 ng ml -1 for "ay" and "ad" subtypes of HBsAg, respectively. The results indicate that the designed assay is comparable to the commercial kits in terms of sensitivity, on-site, specificity, cost, simplicity, portability and reproducibility. The presented method can be used in disadvantaged areas of the world and blood transfusion centers. To the best of our knowledge, this is the first report of using PGMs for HBSAg detection. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. pH responsive label-assisted click chemistry triggered sensitivity amplification for ultrasensitive electrochemical detection of carbohydrate antigen 24-2.

    Science.gov (United States)

    Zheng, Yun; Zhao, Lihua; Ma, Zhanfang

    2018-05-15

    Sensitivity amplification strategy by implementing click chemistry in the construction of biosensing interface can efficiently improve the performance of immunosensor. Herein, we developed a sandwich-type amperometric immunosensor for ultrasensitive detection of carbohydrate antigen 24-2 (CA 242) based on pH responsive label-assisted click chemistry triggered sensitivity amplification strategy. The sensitivity of amperometric immunosensor relies on the current response differences (ΔI) caused by per unit concentration target analyte. The pH responsive Cu 2+ -loaded polydopamine (CuPDA) particles conjugated with detection antibodies were employed as labels, which can release Cu(II) ions by regulating pH. In the presence of ascorbic acid (reductant), Cu(II) ions were reduced to Cu(I) ions. Azide-functionalized double-stranded DNA (dsDNA) as signal enhancer was immobilized on the substrate through Cu + -catalyzed azide/alkyne cycloaddition reaction. With the help of the click reaction, the ΔI caused by target was elevated prominently, resulting in sensitivity amplification of the immunosensor. Under optimal condition, the proposed immunosensor exhibited excellent performance with linear range from 0.0001 to 100 U mL -1 and ultralow detection limit of 20.74 μU mL -1 . This work successfully combines click chemistry with pH-responsive labels in sandwich-type amperometric immunosensor, providing a promising sensitivity amplification strategy to construct immunosensing platform for analysis of other tumor marker. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Commercial bacterins did not induce detectable levels of antibodies in mice against Mycoplasma hyopneumoniae antigens strongly recognized by swine immune system

    Directory of Open Access Journals (Sweden)

    Andressa Fisch

    2016-01-01

    Full Text Available Enzootic Pneumonia (EP caused by Mycoplasma hyopneumoniae results in major economic losses to the swine industry. Hence, the identification of factors that provide protection against EP could help to develop effective vaccines. One such factor that provides partial protection are bacterins. Therefore, the aim of this study was to verify the induction of antibodies against fifteen M. hyopneumoniae antigens, strongly recognized by the swine immune system during natural infection, in mice vaccinated with six commercial bacterins. Each group of mice was inoculated with one bacterin, and seroconversion was assessed by indirect ELISA using recombinant antigens and M. hyopneumoniae 7448 whole cell extract. Sera from one inoculated group recognized antigen MHP_0067, and sera from four inoculated groups recognized antigens MHP_0513 and MHP_0580. None of the bacterins was able to induce seroconversion against the twelve remaining antigens. This absence of a serological response could be attributed to the lack of antigen expression in M. hyopneumoniae strains used in bacterin production. Additionally the partial protection provided by these vaccines could be due to low expression or misfolding of antigens during vaccine preparation. Therefore, the supplementation of bacterins with these recombinant antigens could be a potential alternative in the development of more effective vaccines.

  15. Diagnostic utility of a direct immunofluorescence test to detect feline coronavirus antigen in macrophages in effusive feline infectious peritonitis.

    Science.gov (United States)

    Litster, A L; Pogranichniy, R; Lin, T-L

    2013-11-01

    The antemortem diagnosis of feline infectious peritonitis (FIP) remains challenging in clinical practice, since current testing methods have suboptimal diagnostic accuracy. Immunohistochemical testing of biopsy specimens and postmortem examination are the standard diagnostic methods, although direct immunofluorescence (DIF) testing to detect feline coronavirus in macrophages in effusion specimens has been reported to have 100% specificity and has been recommended as an antemortem confirmatory test. The aim of this study was to compare the results of DIF testing in antemortem feline effusions with postmortem results using field samples. Effusion specimens were collected antemortem from 17 cats and tested by DIF, followed by postmortem examination. Histopathological examination of specimens collected at postmortem confirmed FIP in 10/17 cases and ruled out FIP out in 7/17 cases. Antemortem DIF testing was positive in all 10 cases confirmed as FIP at postmortem examination. In the seven cats where FIP was ruled out at postmortem examination, DIF was negative in five cases and positive in the remaining two cases. The calculated sensitivity of DIF testing was 100% and the specificity was 71.4%. Duplicate effusion specimens from eight cats that were initially DIF positive were stored refrigerated (4 °C) or at room temperature (22-25 °C) and subjected to serial DIF testing to determine the duration of positive results. DIF-positive specimens stored at both temperatures retained their positive status for at least 2 days. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. The genetic diversity of merozoite surface antigen 1 (MSA-1) among Babesia bovis detected from cattle populations in Thailand, Brazil and Ghana.

    Science.gov (United States)

    Nagano, Daisuke; Sivakumar, Thillaiampalam; De De Macedo, Alane Caine Costa; Inpankaew, Tawin; Alhassan, Andy; Igarashi, Ikuo; Yokoyama, Naoaki

    2013-11-01

    In the present study, we screened blood DNA samples obtained from cattle bred in Brazil (n=164) and Ghana (n=80) for Babesia bovis using a diagnostic PCR assay and found prevalences of 14.6% and 46.3%, respectively. Subsequently, the genetic diversity of B. bovis in Thailand, Brazil and Ghana was analyzed, based on the DNA sequence of merozoite surface antigen-1 (MSA-1). In Thailand, MSA-1 sequences were relatively conserved and found in a single clade of the phylogram, while Brazilian MSA-1 sequences showed high genetic diversity and were dispersed across three different clades. In contrast, the sequences from Ghanaian samples were detected in two different clades, one of which contained only a single Ghanaian sequence. The identities among the MSA-1 sequences from Thailand, Brazil and Ghana were 99.0-100%, 57.5-99.4% and 60.3-100%, respectively, while the similarities among the deduced MSA-1 amino acid sequences within the respective countries were 98.4-100%, 59.4-99.7% and 58.7-100%, respectively. These observations suggested that the genetic diversity of B. bovis based on MSA-1 sequences was higher in Brazil and Ghana than in Thailand. The current data highlight the importance of conducting extensive studies on the genetic diversity of B. bovis before designing immune control strategies in each surveyed country.

  17. The Effect of Rapid Antigen Detection Test on Antibiotic Prescription Decision of Clinicians and Reducing Antibiotic Costs in Children with Acute Pharyngitis.

    Science.gov (United States)

    Kose, Engin; Sirin Kose, Seda; Akca, Deniz; Yildiz, Kerem; Elmas, Cengizhan; Baris, Mustafa; Anil, Murat

    2016-08-01

    We aimed to investigate the effect of rapid antigen detection test (RADT) in the diagnosis of streptococcal pharyngitis, its impact on antibiotic prescription decision of pediatricians and influence on reduction of antibiotic treatment costs in children with pharyngitis. The study group consisted of 223 patients who were diagnosed with pharyngitis by pediatricians. The sensitivity and specificity of RADT were 92.1% (95% Cl: 78.6-98.3%) and 97.3% (95% Cl: 93.8-99.1%), respectively. In the first assessment, before performing RADT, pediatricians decided to prescribe antibiotics for 178 (79.8%) patients with pharyngitis. After learning RADT results, pediatricians finally decided to prescribe antibiotics for 83 (37.2%) patients with pharyngitis, and antibiotic prescription decreased by 42.6%. Antibiotic costs in non-Group A streptococcus pharyngitis, Group A streptococcus pharyngitis and all subjects groups decreased by 80.8%, 48%, and 76.4%, respectively. Performing RADT in children with pharyngitis has an important impact on treatment decision of clinicians, reduction of unnecessary antibiotic prescriptions and antibiotic costs. © The Author [2016]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  18. Detection of excretory Entamoeba histolytica DNA in the urine, and detection of E. histolytica DNA and lectin antigen in the liver abscess pus for the diagnosis of amoebic liver abscess

    Directory of Open Access Journals (Sweden)

    Khairnar Krishna

    2007-05-01

    Full Text Available Abstract Background Amoebic liver abscess (ALA and pyogenic liver abscesses (PLA appear identical by ultrasound and other imaging techniques. Collection of blood or liver abscess pus for diagnosis of liver abscesses is an invasive procedure, and the procedure requires technical expertise and disposable syringes. Collection of urine is a noninvasive procedure. Therefore, there has been much interest shown towards the use of urine as an alternative clinical specimen for the diagnosis of some parasitic infections. Here, we report for the first time the detection of E. histolytica DNA excreted in the urine for diagnosis of the cases of ALA. Results E. histolytica DNA was detected in liver abscess pus specimen of 80.4% of ALA patients by a nested multiplex polymerase chain reaction (PCR targeting 16S-like r RNA gene. The nested PCR detected E. histolytica DNA in all 37 (100% liver abscess pus specimens collected prior to metronidazole treatment, but were detected in only 53 of 75 (70.6% pus specimens collected after therapy with metronidazole. Similarly, the PCR detected E. histolytica DNA in 21 of 53 (39.6% urine specimens of ALA patients. The test detected E. histolytica DNA in only 4 of 23 (17.4% urine specimens collected prior to metronidazole treatment, but were detected in 17 of 30 (56.7% urine specimens collected after treatment with metronidazole. The enzyme-linked immunosorbent assay (ELISA for the detection of lectin E. histolytica antigen in the liver abscess pus showed a sensitivity of 50% and the indirect haemagglutination (IHA test for detection of amoebic antibodies in the serum showed a sensitivity of 76.8% for the diagnosis of the ALA. Conclusion The present study for the first time shows that the kidney barrier in ALA patients is permeable to E. histolytica DNA molecule resulting in excretion of E. histolytica DNA in urine which can be detected by PCR. The study also shows that the PCR for detection of E. histolytica DNA in urine of

  19. COLONOSCOPY AND CARCINOEMBRYONIC ANTIGEN VARIATIONS

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    Rita G SOUSA

    2014-03-01

    Full Text Available Context Colonoscopy is essential for synchronous and metachronous cancer detection. Carcinoembryonic antigen is a colorectal cancer tumor marker, important as a follow-up tool in patients with previous colorectal cancer. False-positive carcinoembryonic antigen elevation results in multiples exams and in patient anxiety. In literature, there is reference to transient carcinoembryonic antigen increase with colonoscopy. Objective To evaluate the influence of bowel preparation and colonoscopy in carcinoembryonic antigen blood levels. Methods We prospectively studied subjects that underwent routine colonoscopy in our institution. Blood samples were collected (1 before bowel cleaning, (2 before colonoscopy and (3 immediately after colonoscopy. Blood carcinoembryonic antigen levels were determined by “Sandwich” immunoassay. The statistical methods used were the paired t-test and ANOVA. Results Thirty-seven patients (22M/15F were included; age range 28-84 (mean 56 years. Mean carcinoembryonic antigen values were 1.9, 2 and 1.8 for (1, (2 and (3, respectively. An increase in value (2 compared with (1 was observed in 20/37 patients (P = 0.018, mainly in younger patients and in patients requiring more endoluminal interventions. In 29/37 patients, the CEA value decreased from (2 to (3 (P = 1.3x10-7. Conclusions A trend for carcinoembryonic antigen increase after bowel cleaning was observed, especially in younger patients and in patients with more endoluminal interventions, but without clinical meaning.

  20. Impact of schistosome infection on Plasmodium falciparum Malariometric indices and immune correlates in school age children in Burma Valley, Zimbabwe.

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    Davison T Sangweme

    2010-11-01

    Full Text Available A group of children aged 6-17 years was recruited and followed up for 12 months to study the impact of schistosome infection on malaria parasite prevalence, density, distribution and anemia. Levels of cytokines, malaria specific antibodies in plasma and parasite growth inhibition capacities were assessed. Baseline results suggested an increased prevalence of malaria parasites in children co-infected with schistosomiasis (31% compared to children infected with malaria only (25% (p = 0.064. Moreover, children co-infected with schistosomes and malaria had higher sexual stage geometric mean malaria parasite density (189 gametocytes/µl than children infected with malaria only (73/µl gametocytes (p = 0.043. In addition, a larger percentage of co-infected children (57% had gametocytes as observed by microscopy compared to the malaria only infected children (36% (p = 0.06. There was no difference between the two groups in terms of the prevalence of anemia, which was approximately 64% in both groups (p = 0.9. Plasma from malaria-infected children exhibited higher malaria antibody activity compared to the controls (p = 0.001 but was not different between malaria and schistosome plus malaria infected groups (p = 0.44 and malaria parasite growth inhibition activity at baseline was higher in the malaria-only infected group of children than in the co-infected group though not reaching statistical significance (p = 0.5. Higher prevalence and higher mean gametocyte density in the peripheral blood may have implications in malaria transmission dynamics during co-infection with helminths.

  1. Current progress in the development and use of artemether for chemoprophylaxis of major human schistosome parasites.

    Science.gov (United States)

    Utzinger, J; Xiao, S; Keiser, J; Chen, M; Zheng, J; Tanner, M

    2001-12-01

    Human schistosomiasis, a chronic and debilitating parasitic disease of the tropics, is ranked second after malaria in terms of public health importance. At present, there is no vaccine available, and chemotherapy is the cornerstone of schistosomiasis control. Praziquantel is the drug of choice. Oxamniquine has become difficult to obtain and metrifonate has recently been withdrawn from the market. Rapid re-infection following treatment and concern about praziquantel resistance called for the search of novel drugs for prevention and cure of schistosomiasis. Significant progress has been made with artemether, the methyl ether of dihydroartemisinin, already widely used for the treatment of malaria. The present article reviews the literature that led to the development of artemether for chemoprophylaxis in schistosomiasis, and it summarises the experiences so far obtained with its use to control schistosomiasis in different endemic settings. Topics covered include an overview of the global burden of schistosomiasis and approaches for its control; the nature and features of artemisinin and related derivatives, initially discovered as antimalarials, other bioactivities, and their recent discovery of antischistosomal properties; a historic account disclosing the antischistosomal activity of artemether; in vivo assessment of drug susceptibility of different developmental stages of schistosome parasites; artemether-induced pathology evidenced by scanning and transmission electron microscopy; the possible mechanism of action; in vivo studies with combination therapy of artemether and praziquantel; results of randomised controlled clinical trials of oral artemether for the prevention of patent infection and morbidity; and, ultimately the translation of this knowledge into public health action in different endemic settings towards a more integrated approach of schistosomiasis control.

  2. Regulation of schistosome egg production by HMG CoA reductase

    International Nuclear Information System (INIS)

    VandeWaa, E.A.; Bennett, J.L.

    1986-01-01

    Hydroxymethylglutaryl coenzyme A reductase (HMG CoA reductase) catalyzes the conversion of HMG CoA to mevalonate in the synthesis of steroids, isoprenoids and terpenes. Mevinolin, an inhibitor of this enzyme, decreased egg production in Schistosoma mansoni during in vitro incubations. This was associated with a reduction in the incorporation of 14 C-acetate into polyisoprenoids and a reduction in the formation of a lipid-linked oligosaccharide. In vivo, mevinolin in daily doses of 50 mg/kg (p.o., from days 30-48 post-infection) caused no change in gross liver pathology in S. mansoni infected mice. However, when parasites exposed to mevinolin or its vehicle in vivo were cultured in vitro, worms from mevinolin-treated mice produced six times more eggs than control parasites. When infected mice were dosed with 250 mg/kg mevinolin daily (p.o., from days 35-45 post-infection), liver pathology was reduced in comparison to control mice. Thus, during in vivo exposure to a high dose of the drug egg production is decreased, while at a lower dose it appears unaffected until the parasites are cultured in a drug-free in vitro system wherein egg production is stimulated to extraordinarily high levels. It may be that at low doses mevinolin, by inhibiting the enzyme, is blocking the formation of a product (such as an isoprenoid) which normally acts to down-regulate enzyme synthesis, resulting in enzyme induction. Induction of HMG CoA reductase is then expressed as increased egg production when the worms are removed from the drug. These data suggest that HMG CoA reductase plays a role in schistosome egg production

  3. Presentation of lipid antigens to T cells.

    Science.gov (United States)

    Mori, Lucia; De Libero, Gennaro

    2008-04-15

    T cells specific for lipid antigens participate in regulation of the immune response during infections, tumor immunosurveillance, allergy and autoimmune diseases. T cells recognize lipid antigens as complexes formed with CD1 antigen-presenting molecules, thus resembling recognition of MHC-peptide complexes. The biophysical properties of lipids impose unique mechanisms for their delivery, internalization into antigen-presenting cells, membrane trafficking, processing, and loading of CD1 molecules. Each of these steps is controlled at molecular and celular levels and determines lipid immunogenicity. Lipid antigens may derive from microbes and from the cellular metabolism, thus allowing the immune system to survey a large repertoire of immunogenic molecules. Recognition of lipid antigens facilitates the detection of infectious agents and the initiation of responses involved in immunoregulation and autoimmunity. This review focuses on the presentation mechanisms and specific recognition of self and bacterial lipid antigens and discusses the important open issues.

  4. A study on the prevalence of dog erythrocyte antigen 1.1 and detection of canine Babesia by polymerase chain reaction from apparently healthy dogs in a selected rural community in Zimbabwe

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    Solomon Dhliwayo

    2016-10-01

    Full Text Available A study was carried out to determine the prevalence of blood group antigen dog erythrocyte antigen (DEA 1.1 in mixed breed dogs in rural Chinamhora, Zimbabwe. DEA 1.1 is clinically the most important canine blood group as it is the most antigenic blood type; hence, DEA 1.1 antibodies are capable of causing acute haemolytic, potentially life-threatening transfusion reactions. In this study, blood samples were collected from 100 dogs in Chinamhora, and blood typing was carried out using standardised DEA 1.1 typing strips with monoclonal anti–DEA 1.1 antibodies (Alvedia® LAB DEA 1.1 test kits. Polymerase chain reaction for detecting Babesia spp. antigen was carried out on 58 of the samples. Of the 100 dogs, 78% were DEA 1.1 positive and 22% were DEA 1.1 negative. A significantly (p = 0.02 higher proportion of females (90.5% were DEA 1.1 positive than males (69.0%. The probability of sensitisation of recipient dogs following first-time transfusion of untyped or unmatched blood was 17.2%, and an approximately 3% (2.95% probability of an acute haemolytic reaction following a second incompatible transfusion was found. Babesia spp. antigen was found in 6.9% of the samples. No significant relationship (χ2 = 0.56, p = 0.45 was found between DEA 1.1 positivity and Babesia spp. antigen presence. Despite a low probability of haemolysis after a second incompatibility transfusion, the risk remains present and should not be ignored. Hence, where possible, blood typing for DEA 1.1 is recommended. A survey of DEA 3, 4, 5 and 7 in various breeds is also recommended.

  5. Clinical value of jointly detection serum lactate dehydrogenase/pleural fluid adenosine deaminase and pleural fluid carcinoembryonic antigen in the identification of malignant pleural effusion.

    Science.gov (United States)

    Zhang, Fan; Hu, Lijuan; Wang, Junjun; Chen, Jian; Chen, Jie; Wang, Yumin

    2017-09-01

    Limited data are available for the diagnostic value, and for the diagnostic sensitivity and specificity of joint detection of serum lactate dehydrogenase (sLDH)/pleural fluid adenosine deaminase (pADA) and pleural fluid carcinoembryonic antigen (pCEA) in malignant pleural effusion (MPE). We collected 987 pleural effusion specimens (of which 318 were malignant pleural effusion, 374 were tubercular pleural effusion, and 295 were parapneumonic effusion specimens) from the First Affiliated Hospital of Wenzhou Medical University from July 2012 to March 2016. The pADA, sLDH, pleural fluid LDH (pLDH), serum C-reactive protein (sCRP), pleural fluid protein, pCEA, white blood cell (WBC), and red blood cell (RBC) were analyzed, and the clinical data of each group were collected for statistical analysis. The level of sLDH/pADA, pCEA, and RBC from the MPE group was markedly higher than the tuberculosis pleural effusion (TB) group (Mann-Whitney U=28422.000, 9278.000, 30518, P=.000, .000, .000) and the parapneumonic pleural fluid group (Mann-Whitney U=5972.500, 7113.000, 36750.500, P=.000, .000, .000). The receiver operating characteristic curve ROC showed that the area under the ROC curve (AUC) (=0.924, 0.841) of pCEA and sLDH/pADA (cutoff=4.9, 10.6) were significantly higher than other markers for the diagnosis of MPE. Thus, joint detection of pCEA and sLDH/pADA suggested that the sensitivity, specificity, and AUC was 0.94, 81.70, and 94.32 at the cutoff 0.16 and diagnostic performance was higher than pCEA or sLDH/pADA. Joint detection of sLDH/pADA and pCEA can be used as a good indicator for the identification of benign and MPE with higher sensitivity and specificity than pCEA or sLDH/pADA. © 2016 Wiley Periodicals, Inc.

  6. Deteksi Antigen pada Kriptokokosis

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    Robiatul Adawiyah

    2014-12-01

    , laboratory and radiologicalexaminations. Laboratory examinations performed by morphological identification, serology and PCR. Morphological examination with India ink is positive when the number of fungi is around 10 10  cells/ml. Cultur examination is performed in Sabouraud dextrose agar (SDA and niger sheed agar (NSA medium, fungi grows in 5-7 days. Antigen and antibody detection could be performed on body fluid and do not take a long time. Detection of Cr. neoformans antibody can not show positive result in acute infection, IgA still positive after 1-2 years of healing phase and IgG can be persistent. The immunocompromised person showed very complex result and inconsistent in determining the diagnosis. Polysaccharides are the most instrumental component in Cr. neoformans virulence. The component of Polysaccharide especially glucuronoxylomannan is the most important marker in thediagnosis of cryptococcosis. Antigen detection of Cr. neoformans can show positive result in acute/chronic infection, high sensitivity and specificity. Polysaccharides can be detected from 10 ng/ ml of body fluid, so in minimal level of antigen we still can diagnose cryptococcosis.Keywords: Cr. neoformans, glucuronoxylomannan, antigen

  7. No apparent reduction in schistosome burden or genetic diversity following four years of school-based mass drug administration in mwea, central kenya, a heavy transmission area.

    Science.gov (United States)

    Lelo, Agola E; Mburu, David N; Magoma, Gabriel N; Mungai, Ben N; Kihara, Jimmy H; Mwangi, Ibrahim N; Maina, Geoffrey M; Kinuthia, Joseph M; Mutuku, Martin W; Loker, Eric S; Mkoji, Gerald M; Steinauer, Michelle L

    2014-10-01

    Schistosomiasis is a debilitating neglected tropical disease that infects over 200 million people worldwide. To combat this disease, in 2012, the World Health Organization announced a goal of reducing and eliminating transmission of schistosomes. Current control focuses primarily on mass drug administration (MDA). Therefore, we monitored transmission of Schistosoma mansoni via fecal egg counts and genetic markers in a typical school based MDA setting to ascertain the actual impacts of MDA on the targeted schistosome population. For 4 years, we followed 67 children enrolled in a MDA program in Kenya. Infection status and egg counts were measured each year prior to treatment. For 15 of these children, for which there was no evidence of acquired resistance, meaning they became re-infected following each treatment, we collected microsatellite genotype data from schistosomes passed in fecal samples as a representation of the force of transmission between drug treatments. We genotyped a total of 4938 parasites from these children, with an average of 329.2 parasites per child for the entire study, and an average of 82.3 parasites per child per annual examination. We compared prevalence, egg counts, and genetic measures including allelic richness, gene diversity (expected heterozygosity), adult worm burdens and effective number of breeders among time points to search for evidence for a change in transmission or schistosome populations during the MDA program. We found no evidence of reduced transmission or schistosome population decline over the course of the program. Although prevalence declined in the 67 children as it did in the overall program, reinfection rates were high, and for the 15 children studied in detail, schistosome egg counts and estimated adult worm burdens did not decline between years 1 and 4, and genetic diversity increased over the course of drug treatment. School based control programs undoubtedly improve the health of individuals; however, our data

  8. Locus-specific detection of HLA-DQ and -DR antigens by antibodies against synthetic N-terminal octapeptides of the beta chain

    DEFF Research Database (Denmark)

    Deufel, T; Grove, A; Kofod, Hans

    1985-01-01

    Antibodies against synthetic peptides representing the class-II antigen HLA-DR and -DQ beta chain N-terminal sequences were prepared in rabbits. The two octapeptides only share two amino acids and enzyme-linked immuno-assays showed the antisera only to bind to its own antigen. Both peptide antisera...... chains of HLA-DR and -DQ have been prepared by the preparation by the production of antibodies against the N-terminal sequences of each polypeptide....

  9. Improvements on an ELISA to detect trypanosomal antigens and its use as a monitoring tool in tsetse and trypanosomosis control programmes

    Energy Technology Data Exchange (ETDEWEB)

    Dwinger, R H; Rebeski, D; Winger, E [Joint FAO/IAEA Div. of Nuclear Techniques in Food and Agriculture, Vienna (Austria). Animal Production and Health Section

    1997-02-01

    Monoclonal antibodies directed at epitopes of Trypanosoma brucei, T. congolense and T. vivax have been used to capture and detect trypanosomal antigens in bovine blood samples using an enzyme-linked immunosorbent assay (ELISA) developed elsewhere. The test has been transformed in a ready-to-use kit format for distribution among a network of 15 African research institutes. The specificity of the test was assessed under experimental and field conditions and found to be 96% ({+-} 2%) for T. brucei, 99.5% ({+-}1%) for T. congolense and 99% ({+-}1%) for T. vivax. Following a validation period under field conditions, adjustments were made to the protocol to increase the sensitivity of the ELISA and to improve the suitability of the test for laboratory use under African conditions. Presently the ag-ELISA is being applied in conjunction with conventional parasitological techniques such as the buffy coat technique (BCT) to monitor progress in various tsetse and trypanosomosis control programmes and in a tsetse eradication effort on the island of Zanzibar. The two tests complement each other; the serological test tends to produce more false negatives during subacute infections, while the parasitological techniques tend to produce more false negatives during chronic infections. Since the sensitivity of the ELISA is not optimal, research efforts at the FAO/IAEA Agriculture and Biotechnology Laboratory will be focused on improving this aspect. However, these efforts are severely hampered by the lack of a diagnostic test that can be used as a ``gold standard``. The use of the polymerase chain reaction for verifying doubtful test results and as a possible candidate for a ``gold standard`` to diagnose trypanosomosis are discussed. Finally, future plans are outlined to initiate the use of geographical information systems to assess the impact of tsetse control and eradication programmes on land use and disease distribution. (author). 8 refs.

  10. Evaluation of a rapid antigen detection test in the diagnosis of streptococcal pharyngitis in children and its impact on antibiotic prescription.

    Science.gov (United States)

    Maltezou, Helen C; Tsagris, Vasilios; Antoniadou, Anastasia; Galani, Labrini; Douros, Constantinos; Katsarolis, Ioannis; Maragos, Antonios; Raftopoulos, Vasilios; Biskini, Panagiota; Kanellakopoulou, Kyriaki; Fretzayas, Andreas; Papadimitriou, Theodoros; Nicolaidou, Polyxeni; Giamarellou, Helen

    2008-12-01

    To study the performance of the Becton-Dickinson Link 2 Strep A Rapid Test, a rapid antigen detection test (RADT) for diagnosing streptococcal pharyngitis in children presenting to private offices and to the Pediatric Outpatient Clinic of a university hospital, in relation to clinical criteria (fever, tender anterior cervical lymph nodes, tonsillar exudate and absence of cough), and its impact on antibiotic prescription. Children were enrolled in Group A (enrolment by private-practice paediatricians; diagnosis by clinical picture only), Group B (enrolment by private-practice paediatricians; diagnosis by RADT and culture) or Group C (enrolment by hospital-affiliated paediatricians in the Pediatric Outpatient Clinic; diagnosis by RADT and culture). During a 2 year period, 820 children were enrolled [369 (45%) in Group A, 270 (33%) in Group B and 181 (22%) in Group C]. Streptococcal pharyngitis was diagnosed by RADT and culture in 146 (32.4%) of the 451 tested children. The sensitivity, specificity and positive and negative predictive values of the RADT were 83.1%, 93.3%, 82.4% and 93.6%, respectively. A stepwise increase in the sensitivity of the RADT was noted among children with one, two, three or four clinical criteria (60.9% to 95.8%). Paediatricians without access to laboratory tests were more likely to prescribe antibiotics compared with paediatricians with access to tests (72.2% versus 28.2%, P antibiotics more frequently compared with hospital-affiliated paediatricians (55.7% versus 19.9%, P antibiotic administration. Such a strategy has an important impact on limiting throat culture testing and is associated with reduced antibiotic prescription.

  11. Long-Term Effects of Antibodies Against Human Leukocyte Antigens Detected by Flow Cytometry in the First Year After Renal Transplantation

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    Tülay Kılıçaslan Ayna

    2013-03-01

    Full Text Available Objective: In this study, we aimed to investigate the incidence, dynamics and profiles of human leukocyte antigen (HLA-directed antibodies developed after transplantation and their impact on graft rejection and outcome in kidney recipients. Study Design: Prospective follow-up study. Material and Methods: A total of 56 kidney recipients were monitored at 1st, 6th and 12th months for the development of anti-HLA antibodies using bead based flow-cytometry assays (Flow PRA tests. Results: In 21 (37.5% patients, panel reactive antibodies (PRA was positive after transplantation, however, in 35 (62.5% patients PRA was found negative. Twelve (57.1% patients with post-transplantation HLA-reactive antibodies [PRA (+] and 8 (22.9% patients with no detectable alloantibodies [PRA (-] were developed allograft rejection (p=0.010. In the PRA positive patient group the rates of early period infection and delayed graft function (DGF were higher than the PRA negative patient group. Serum creatinine levels of PRA positive group at 6. and 12. months after transplantation were significantly higher than the PRA negative group (p=0.015 and p=0.048, respectively. The rejection rates of patients who had class I and II HLA antibodies were significantly higher than the patients who had either class I or II HLA antibodies (p=0.011. Acute rejection rates were significantly higher in patients who had class I and II HLA antibodies at the first month (p=0.007. Conclusion: Higher occurrence of rejection episodes in PRA positive group may show the importance of anti-HLA antibody monitoring using Flow-PRA after renal transplantation as a prognostic marker in terms of graft survival.

  12. Evaluation of circulating cathodic antigen (CCA) strip for diagnosis of urinary schistosomiasis in Hassoba school children, Afar, Ethiopia

    OpenAIRE

    Ayele B.; Erko B.; Legesse M.; Hailu A.; Medhin G.

    2008-01-01

    A total of 206 urine samples collected from Hassoba Elementary schoolchildren, Afar, Ethiopia, a low Schistosoma haematobium endemic setting, was diagnosed to evaluate the performance of CCA strip using double references, urine filtration technique and urinalysis dipstick (Combur 10 Test®) that detect schistosome eggs and blood in urine, respectively. The former was used as a gold standard reference method. Sensitivity, specificity, positive and negative predictive values for the CCA were 52%...

  13. Combined detection of Twist1, Snail1 and squamous cell carcinoma antigen for the prognostic evaluation of invasion and metastasis in cervical squamous cell carcinoma.

    Science.gov (United States)

    Yang, Huilun; Hu, Haiyang; Gou, Yanling; Hu, Yuhong; Li, Hui; Zhao, Hongwei; Wang, Beidi; Li, Peiling; Zhang, Zongfeng

    2018-04-01

    Cervical cancer is one of the most common malignant tumours of the female reproductive system, ranking second only to breast cancer in morbidity worldwide. Essential features of the progression of cervical cancer are invasion and metastasis, which are closely related to disease prognosis and mortality rate. At the present time there is no effective method to evaluate cancer invasion and metastasis before surgery. Here we report our study on molecular changes in biopsy tissue for the prognostic evaluation of cancer invasion and metastasis. Expression of the epithelial-mesenchymal transition-inducing transcription factors Twist1 and Snail1 was detected by immunohistochemistry in 32 normal, 36 low-grade squamous intraepithelial neoplasia (LSIL), 54 high-grade squamous intraepithelial neoplasia (HSIL) and 320 cervical squamous cell carcinoma (CSCC) samples. The correlation between the expression of Twist1, Snail1 and squamous cell carcinoma antigen (SCCA) in CSCC tissues and clinical pathology results was evaluated. A transwell migration and invasion assay was used to explore the roles of Twist1 and Snail1 in the invasion of cancer cells. Lymph node metastasis and lymphovascular space invasion (LVSI) rates for the following groups were analysed: SCCA(+) group, Twist1(+) group, Snail1(+) group, Twist1(+)Snail1(+)group, Twist1(+)SCCA(+)group, Snail1(+)SCCA(+)group and Twist1(+)Snail1(+)SCCA(+) group. The expression of Twist1 and Snail1 was significantly upregulated in HSIL and CSCC (p  0.05). The expression of SCCA was associated with LVSI, lymph node metastasis, FIGO stage and histological grade (p  0.05). Twist1 was an independent factor contributing to the invasion ability of cervical cancer cells. In addition, the positive rate of lymph node metastasis and LVSI was higher in the Twist1(+)Snail1(+)SCCA(+) group than in the SCCA(+) group, Twist1(+) group and Snail1(+) group, respectively (p < 0.05). Combined detection of Twist1 and Snail1 in SCCA-positive biopsy

  14. A new trivalent SnSAG surface antigen chimera for efficient detection of antibodies against Sarcocystis neurona and diagnosis of equine protozoal myeloencephalitis.

    Science.gov (United States)

    Yeargan, Michelle; de Assis Rocha, Izabela; Morrow, Jennifer; Graves, Amy; Reed, Stephen M; Howe, Daniel K

    2015-05-01

    Enzyme-linked immunosorbent assays (ELISAs) based on the SnSAG surface antigens of Sarcocystis neurona provide reliable detection of infection by the parasite. Moreover, accurate serodiagnosis of equine protozoal myeloencephalitis (EPM) is achieved with the SnSAG ELISAs by measuring antibodies in serum and cerebrospinal fluid (CSF) to reveal active infection in the central nervous system. Two independent ELISAs based on recombinant (r)SnSAG2 or a chimeric fusion of SnSAG3 and SnSAG4 (rSnSAG4/3) are currently used together for EPM serodiagnosis to overcome varied antibody responses in different horses. To achieve reliable antibody detection with a single ELISA instead of 2 separate ELISAs, rSnSAG2 was fused with rSnSAG4/3 into a single trivalent protein, designated rSnSAG2/4/3. Paired serum and CSF from 163 horses were tested with all 3 ELISAs. When the consensus antibody titers obtained with the rSnSAG2 and rSnSAG4/3 ELISAs were compared to the single SAG2/4/3 ELISA titers, Spearman rank correlation coefficients of ρ = 0.74 and ρ = 0.90 were obtained for serum and CSF, respectively, indicating strong agreement between the tests. When the rSnSAG2 and rSnSAG4/3 consensus serum-to-CSF titer ratio was compared to the rSnSAG2/4/3 serum-to-CSF titer ratio, the Spearman correlation coefficient was ρ = 0.87, again signifying strong agreement. Importantly, comparing the diagnostic interpretation of the serum-to-CSF titer ratios yielded a Cohen kappa value of 0.77. These findings suggest that the single ELISA based on the trivalent rSnSAG2/4/3 will provide serologic and diagnostic results that are highly comparable to the consensus of the 2 independent ELISAs based on rSnSAG2 and rSnSAG4/3. © 2015 The Author(s).

  15. Comparison of a Clinical Prediction Rule and a LAM Antigen-Detection Assay for the Rapid Diagnosis of TBM in a High HIV Prevalence Setting

    Science.gov (United States)

    Patel, Vinod B.; Singh, Ravesh; Connolly, Cathy; Kasprowicz, Victoria; Zumla, Allimudin; Ndungu, Thumbi; Dheda, Keertan

    2010-01-01

    Background/Objective The diagnosis of tuberculous meningitis (TBM) in resource poor TB endemic environments is challenging. The accuracy of current tools for the rapid diagnosis of TBM is suboptimal. We sought to develop a clinical-prediction rule for the diagnosis of TBM in a high HIV prevalence setting, and to compare performance outcomes to conventional diagnostic modalities and a novel lipoarabinomannan (LAM) antigen detection test (Clearview-TB®) using cerebrospinal fluid (CSF). Methods Patients with suspected TBM were classified as definite-TBM (CSF culture or PCR positive), probable-TBM and non-TBM. Results Of the 150 patients, 84% were HIV-infected (median [IQR] CD4 count = 132 [54; 241] cells/µl). There were 39, 55 and 54 patients in the definite, probable and non-TBM groups, respectively. The LAM sensitivity and specificity (95%CI) was 31% (17;48) and 94% (85;99), respectively (cut-point ≥0.18). By contrast, smear-microscopy was 100% specific but detected none of the definite-TBM cases. LAM positivity was associated with HIV co-infection and low CD4 T cell count (CD4200 cells/µl; p = 0.03). The sensitivity and specificity in those with a CD4<100 cells/µl was 50% (27;73) and 95% (74;99), respectively. A clinical-prediction rule ≥6 derived from multivariate analysis had a sensitivity and specificity (95%CI) of 47% (31;64) and 98% (90;100), respectively. When LAM was combined with the clinical-prediction-rule, the sensitivity increased significantly (p<0.001) to 63% (47;68) and specificity remained high at 93% (82;98). Conclusions Despite its modest sensitivity the LAM ELISA is an accurate rapid rule-in test for TBM that has incremental value over smear-microscopy. The rule-in value of LAM can be further increased by combination with a clinical-prediction rule, thus enhancing the rapid diagnosis of TBM in HIV-infected persons with advanced immunosuppression. PMID:21203513

  16. Optimisation of the CT h4S bioassay for detection of human interleukin-4 secreted by mononuclear cells stimulated by phytohaemaglutinin or by human leukocyte antigen mismatched mixed lymphocyte culture

    DEFF Research Database (Denmark)

    Petersen, Søren Lykke; Russell, Charlotte Astrid; Bendtzen, Klaus

    2002-01-01

    S bioassay detects 5 pg/ml of human recombinant IL-4 with no detection of IL-2 in concentrations below 500 pg/ml. We have found 72 h of culture optimal for detection of IL-2 and IL-4 produced by human mononuclear cells (MNC) in response to stimulation with phytohaemaglutinin and for detection of IL......-2 in human leukocyte antigen (HLA)-mismatched mixed leukocyte culture (MLC). An interindividual variation in cytokine accumulation was demonstrated for IL-4 but not for IL-2. With the use of 5x10(4) responder cells/well no IL-4 could be detected in HLA-mismatched MLC between days 1 and 16. The lack...

  17. Evaluation of antigen detection and polymerase chain reaction for diagnosis of amoebic liver abscess in patients on anti-amoebic treatment

    Directory of Open Access Journals (Sweden)

    Jaiswal Virendra

    2012-08-01

    Full Text Available Abstract Background Diagnosis of amoebic liver abscess (ALA in patients on anti-amoebic drugs is difficult. There is scanty data on this issue using Entamoeba histolytica (E. histolytica lectin antigen and polymerase chain reaction (PCR. We studied utility of lectin antigen, PCR, and IgG antibody in diagnosis of liver abscess in patients on anti-amoebic treatment. Liver aspirate of 200 patients, of which 170 had anti-amoebic drug prior to drainage, was tested for E. histolytica lectin antigen by (ELISA, PCR, bacterial culture, and serum IgG antibody by (ELISA. Classification of abscesses was based on result of anti-amoebic IgG antibody and bacterial culture, E. histolytica PCR and bacterial culture, and E. histolytica lectin antigen and bacterial culture. Findings Using anti-amoebic IgG antibody and bacterial culture, 136/200 (68.0% were classified as ALA, 12/200 (6.0% as pyogenic liver abscess (PLA, 29/200 (14.5% as mixed infection, and 23/200 (11.5% remained unclassified. Using amoebic PCR and bacterial culture 151/200 (75.5% were classified as ALA, 25/200 (12.5% as PLA, 16/200 (8.0% as mixed infection, and 8/200 (4.0% remained unclassified. With E. histolytica lectin antigen and bacterial culture, 22/200 (11.0% patients were classified as ALA, 39/200 (19.5% as PLA, 2/200 (1.0% as mixed infection, and 137/200 (68.5% remained unclassified. Conclusions E. histolytica lectin antigen was not suitable for classification of ALA patients who had prior anti-amoebic treatment. However, PCR may be used as alternative test to anti-amoebic antibody in diagnosis of ALA.

  18. Radioimmunoassay for tumor antigen of human cervical squamous cell carcinoma

    International Nuclear Information System (INIS)

    Kato, H.; Torigoe, T.

    1977-01-01

    A heterologous antiserum for human cervical squamous cell carcinoma was prepared and specificity determined by Ouchterlony immunodiffusion and immunofluorescence studies. With this antiserum, a tumor antigen was purified from human cervical squamous cell carcinoma tissue. The specificities of the antigen and the antiserum were then re-examined by a radioimmunoassay method using 125 I-labeled purified antigen. Although normal cervical tissue extract showed a moderate cross-reactivity in the radioimmunoassay, the circulating antigen activity could not be detected in normal women or in several patients with other carcinomas, whereas 27 of 35 patients with cervical squamous cell carcinoma showed detectable serum antigen activity. All patients with advanced stages of cervical squamous cell carcinoma showed detectable antigen levels. These results indicate that there is a quantitative abnormality, at least, of this tumor antigen in patients with cervical squamous cell carcinoma and that the radioimmunoassay for the antigen is a potentially useful tool in clinical care

  19. A protein-conjugate approach to develop a monoclonal antibody-based antigen detection test for the diagnosis of human brucellosis

    NARCIS (Netherlands)

    Patra, Kailash P.; Saito, Mayuko; Atluri, Vidya L.; Rolán, Hortensia G.; Young, Briana; Kerrinnes, Tobias; Smits, Henk; Ricaldi, Jessica N.; Gotuzzo, Eduardo; Gilman, Robert H.; Tsolis, Renee M.; Vinetz, Joseph M.

    2014-01-01

    Human brucellosis is most commonly diagnosed by serology based on agglutination of fixed Brucella abortus as antigen. Nucleic acid amplification techniques have not proven capable of reproducibly and sensitively demonstrating the presence of Brucella DNA in clinical specimens. We sought to optimize

  20. Antigen-specific secretion of IFNγ and CXCL10 in whole blood assay detects Mycobacterium leprae infection but does not discriminate asymptomatic infection from symptomatic leprosy.

    Science.gov (United States)

    Hungria, Emerith Mayra; Freitas, Aline Araújo; Pontes, Maria Araci Andrade; Gonçalves, Heitor Sá; Sousa, Ana Lúcia Osório Maroccolo; Costa, Maurício Barcelos; Castilho, Mirian Lane Oliveira Rodrigues; Duthie, Malcolm S; Stefani, Mariane Martins Araújo

    2017-04-01

    To advance toward a whole blood assay (WBA)-based test capable of facilitating the diagnosis of paucibacillary (PB) leprosy, we evaluated a prototype in-tube WBA using combinations of Mycobacterium leprae antigens. Blood was collected from newly diagnosed untreated PB (n=38), multibacillary (MB) (n=30), healthy household contacts (HHC) of MB (n=27), and endemic controls (n=61) residing in Goiânia and Fortaleza, Brazil. Blood was incubated with M. leprae cell sonicate, recombinant proteins (46f+LID-1; ML0276+LID-1), or controls (phosphate-buffered saline, phytohemagglutinin, M. tuberculosis purified protein derivative). Antigen-specific IFNγ production was observed in 71-84% and 55% of PB and HHC, respectively. Antigen-specific CXCL10 levels were similarly assessed to determine if, unlike IFNγ, CXCL10 could differentiate PB from HHC with repeated exposure/asymptomatic M. leprae infection. The CXCL10 levels induced in response to M. leprae antigens could not, however, differentiate PB from HHC. Despite these limitations, the WBAs reported here still represent important tools for assessing M. leprae infection rates and evaluating the impact of control measures. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Utility of a stool antigen test to detect the incidence of helicobacter pylori infection and familial and community enviromental risk factors for this infection in pediatric age.

    Science.gov (United States)

    Sabbi, T; Dall'Oglio, L; De Angelis, P; Torroni, E; Colistro, F; Azzolina, M; Santoni, A; Di Ciommo, V; Benedetto, M

    2012-01-01

    Helicobacter pylori (Hp) infection is mainly acquired during childhood; it is recognised as a cause of gastritis and peptic ulcer and it has been classified as a group A carcinogen by World Health Organization. The exact mode of transmission is as yet, not known. Aim of our study has been to identify risk factors associated with Helicobacter pylori infection in a preschool and school population and to confirm if Hp antigen in faeces is useful as screening in epidemiological studies. We interviewed, with questionnaire, 400 children (203 male; age range 3-10 years; mean age 6 years) of 3 different schools and stool samples were collected of all children too. 35 of 400 (8%) children underwent to upper gastrointestinal endoscopy because of a suspect of upper gastrointestinal disease. stool were collected from 400 school children and 35 of them shown positivity of Hp antigen test. A questionnaire about presence of nausea, vomit, recurrent abdominal pain, family size, parent's occupations and education, use of antibiotics, country of birth of child and parents, personal hygiene, breast feeding, presence of the animals was completed. 35 children with positive Hp stool antigen test and a suspicious of upper gastrointestinal disease (recurrent abdominal pain, diurnal or nocturnal abdominal pain, nausea, vomiting, iron deficiency) underwent to esophagogastroduodenoscopy (EGDS) that demonstrated antral gastritis and positive histology and urease rapid test. the results of this study suggest that risk factors for Hp infection are low socioeconomics factors, hygiene and living conditions and that Hp antigen in faeces is useful as screening test.

  2. Technical and clinical performance of a new assay to detect squamous cell carcinoma antigen levels for the differential diagnosis of cervical, lung, and head and neck cancer.

    Science.gov (United States)

    Holdenrieder, Stefan; Molina, Rafael; Qiu, Ling; Zhi, Xiuyi; Rutz, Sandra; Engel, Christine; Kasper-Sauer, Pia; Dayyani, Farshid; Korse, Catharina M

    2018-04-01

    In squamous cell carcinoma, squamous cell carcinoma antigen levels are often elevated. This multi-center study evaluated the technical performance of a new Elecsys ® squamous cell carcinoma assay, which measures serum squamous cell carcinoma antigen 1 and 2 levels in an equimolar manner, and investigated the potential of squamous cell carcinoma antigen for differential diagnosis of cervical, lung, and head and neck squamous cell carcinoma.Assay precision and method comparison experiments were performed across three European sites. Reference ranges for reportedly healthy individuals were determined using samples from banked European and Chinese populations. Differential diagnosis experiments determined whether cervical, lung, or head and neck cancer could be differentiated from apparently healthy, benign, or other malignant cohorts using squamous cell carcinoma antigen levels alone. Squamous cell carcinoma antigen cut-off levels were calculated based on squamous cell carcinoma antigen levels at 95% specificity. Repeatability coefficients of variation across nine analyte concentrations were ≤5.3%, and intermediate precision coefficients of variation were ≤10.3%. Method comparisons showed good correlations with Architect and Kryptor systems (slopes of 1.1 and 1.5, respectively). Reference ranges for 95th percentiles for apparently healthy individuals were 2.3 ng/mL (95% confidence interval: 1.9-3.8; European cohort, n = 153) and 2.7 ng/mL (95% confidence interval: 2.2-3.3; Chinese cohort, n = 146). Strongest differential diagnosis results were observed for cervical squamous cell carcinoma: receiver operating characteristic analysis showed that squamous cell carcinoma antigen levels (2.9 ng/mL cut-off) differentiate cervical squamous cell carcinoma (n = 127) from apparently healthy females (n = 286; area under the curve: 86.2%; 95% confidence interval: 81.8-90.6; sensitivity: 61.4%; specificity: 95.6%), benign diseases (n = 187; area

  3. Schistosome tegumental ecto-apyrase (SmATPDase1 degrades exogenous pro-inflammatory and pro-thrombotic nucleotides

    Directory of Open Access Journals (Sweden)

    Akram A. Da’dara

    2014-03-01

    Full Text Available Schistosomes are parasitic worms that can survive in the hostile environment of the human bloodstream where they appear refractory to both immune elimination and thrombus formation. We hypothesize that parasite migration in the bloodstream can stress the vascular endothelium causing this tissue to release chemicals alerting responsive host cells to the stress. Such chemicals are called damage associated molecular patterns (DAMPs and among the most potent is the proinflammatory mediator, adenosine triphosphate (ATP. Furthermore, the ATP derivative ADP is a pro-thrombotic molecule that acts as a strong activator of platelets. Schistosomes are reported to possess at their host interactive tegumental surface a series of enzymes that could, like their homologs in mammals, degrade extracellular ATP and ADP. These are alkaline phosphatase (SmAP, phosphodiesterase (SmNPP-5 and ATP diphosphohydrolase (SmATPDase1. In this work we employ RNAi to knock down expression of the genes encoding these enzymes in the intravascular life stages of the parasite. We then compare the abilities of these parasites to degrade exogenously added ATP and ADP. We find that only SmATPDase1-suppressed parasites are significantly impaired in their ability to degrade these nucleotides. Suppression of SmAP or SmNPP-5 does not appreciably affect the worms’ ability to catabolize ATP or ADP. These findings are confirmed by the functional characterization of the enzymatically active, full-length recombinant SmATPDase1 expressed in CHO-S cells. The enzyme is a true apyrase; SmATPDase1 degrades ATP and ADP in a cation dependent manner. Optimal activity is seen at alkaline pH. The Km of SmATPDase1 for ATP is 0.4 ± 0.02 mM and for ADP, 0.252 ± 0.02 mM. The results confirm the role of tegumental SmATPDase1 in the degradation of the exogenous pro-inflammatory and pro-thrombotic nucleotides ATP and ADP by live intravascular stages of the parasite. By degrading host inflammatory signals

  4. Prostate-Specific Antigen (PSA) Test

    Science.gov (United States)

    ... Cancer Prostate Cancer Screening Research Prostate-Specific Antigen (PSA) Test On This Page What is the PSA ... parts of the body before being detected. The PSA test may give false-positive or false-negative ...

  5. Identification of antigenic proteins of setaria cervi by immunoblotting technique

    International Nuclear Information System (INIS)

    Kaushal, N.A.; Kaushal, D.C.; Ghatak, S.

    1987-01-01

    Identification and characterization of antigenic proteins of Setaria cervi (bovine filarial parasite) adults and microfilariae was done by immunoblotting technique using hyperimmune rabbit sera against S. cervi and Brugia malayi. The antigens recognized by these sera were detected by using 125 I protein-A followed by autoradiography. Fifteen different antigens were observed to be common between adult and microfilarial stages of the parasite. Some stage specific antigens were also identified. Many antigens of S. cervi adults and microfilariae were also recognized by rabbit anti-B.malayi serum showing the existence of common antigenic determinants between the bovine and human filarial parasites

  6. Quantitative Detection of the Foot-And-Mouth Disease Virus Serotype O 146S Antigen for Vaccine Production Using a Double-Antibody Sandwich ELISA and Nonlinear Standard Curves.

    Directory of Open Access Journals (Sweden)

    Xia Feng

    Full Text Available The efficacy of an inactivated foot-and-mouth disease (FMD vaccine is mainly dependent on the integrity of the foot-and-mouth disease virus (FMDV particles. At present, the standard method to quantify the active component, the 146S antigen, of FMD vaccines is sucrose density gradient (SDG analysis. However, this method is highly operator dependent and difficult to automate. In contrast, the enzyme-linked immunosorbent assay (ELISA is a time-saving technique that provides greater simplicity and sensitivity. To establish a valid method to detect and quantify the 146S antigen of a serotype O FMD vaccine, a double-antibody sandwich (DAS ELISA was compared with an SDG analysis. The DAS ELISA was highly correlated with the SDG method (R2 = 0.9215, P<0.01. In contrast to the SDG method, the DAS ELISA was rapid, robust, repeatable and highly sensitive, with a minimum quantification limit of 0.06 μg/mL. This method can be used to determine the effective antigen yields in inactivated vaccines and thus represents an alternative for assessing the potency of FMD vaccines in vitro. But it still needs to be prospectively validated by analyzing a new vaccine preparation and determining the proper protective dose followed by an in vivo vaccination-challenge study to confirm the ELISA findings.

  7. Quantitative Detection of the Foot-And-Mouth Disease Virus Serotype O 146S Antigen for Vaccine Production Using a Double-Antibody Sandwich ELISA and Nonlinear Standard Curves

    Science.gov (United States)

    Feng, Xia; Ma, Jun-Wu; Sun, Shi-Qi; Guo, Hui-Chen; Yang, Ya-Min; Jin, Ye; Zhou, Guang-Qing; He, Ji-Jun; Guo, Jian-Hong; Qi, Shu-yun; Lin, Mi; Cai, Hu; Liu, Xiang-Tao

    2016-01-01

    The efficacy of an inactivated foot-and-mouth disease (FMD) vaccine is mainly dependent on the integrity of the foot-and-mouth disease virus (FMDV) particles. At present, the standard method to quantify the active component, the 146S antigen, of FMD vaccines is sucrose density gradient (SDG) analysis. However, this method is highly operator dependent and difficult to automate. In contrast, the enzyme-linked immunosorbent assay (ELISA) is a time-saving technique that provides greater simplicity and sensitivity. To establish a valid method to detect and quantify the 146S antigen of a serotype O FMD vaccine, a double-antibody sandwich (DAS) ELISA was compared with an SDG analysis. The DAS ELISA was highly correlated with the SDG method (R2 = 0.9215, P<0.01). In contrast to the SDG method, the DAS ELISA was rapid, robust, repeatable and highly sensitive, with a minimum quantification limit of 0.06 μg/mL. This method can be used to determine the effective antigen yields in inactivated vaccines and thus represents an alternative for assessing the potency of FMD vaccines in vitro. But it still needs to be prospectively validated by analyzing a new vaccine preparation and determining the proper protective dose followed by an in vivo vaccination-challenge study to confirm the ELISA findings. PMID:26930597

  8. Assessment of the repeatability and border-plate effects of the B158/B60 enzyme-linked-immunosorbent assay for the detection of circulating antigens (Ag-ELISA) of Taenia saginata.

    Science.gov (United States)

    Jansen, Famke; Dorny, Pierre; Berkvens, Dirk; Van Hul, Anke; Van den Broeck, Nick; Makay, Caroline; Praet, Nicolas; Gabriël, Sarah

    2016-08-30

    The monoclonal antibody-based circulating antigen detecting ELISA (B158/B60 Ag-ELISA) has been used elaborately in several studies for the diagnosis of human, bovine and porcine cysticercosis. Interpretation of test results requires a good knowledge of the test characteristics, including the repeatability and the effect of the borders of the ELISA plates. Repeatability was tested for 4 antigen-negative and 5 antigen-positive reference bovine serum samples by calculating the Percentage Coefficient of Variation (%CV) within and between plates, within and between runs, overall, for two batches of monoclonal antibodies and by 2 laboratory technicians. All CV values obtained were below 20% (except one: 24.45%), which indicates a good repeatability and a negligible technician error. The value of 24.45% for indicating the variability between batches of monoclonal antibodies for one positive sample is still acceptable for repeatability measures. Border effects were determined by calculating the %CV values between the inner and outer wells of one plate for 2 positive serum samples. Variability is a little more present in the outer wells but this effect is very small and no significant border effect was found. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Detection of different Leishmania spp. and Trypanosoma cruzi antibodies in cats from the Yucatan Peninsula (Mexico) using an iron superoxide dismutase excreted as antigen.

    Science.gov (United States)

    Longoni, Silvia S; López-Cespedes, Angeles; Sánchez-Moreno, Manuel; Bolio-Gonzalez, Manuel E; Sauri-Arceo, Carlos H; Rodríguez-Vivas, Roger I; Marín, Clotilde

    2012-09-01

    Although human leishmaniasis has been reported in 20 states in Mexico, no case of leishmaniasis has been reported in cats to date. In the Yucatan Peninsula, it has been found that dogs may act as reservoirs for at least three Leishmania species (Leishmania mexicana, Leishmania braziliensis, and Leishmania panamensis). In this study we identified specific antibodies against these three Leishmania spp. and Trypanosoma cruzi in the sera from 95 cats from two States on the Yucatan Peninsula, namely Quintana Roo and Yucatan, by ELISA and Western blot techniques using whole extract and an iron superoxide dismutase excreted by the parasites as antigens. As well as demonstrating the presence of trypanosomatid antibodies in the feline population on the Yucatan Peninsula, we were also able to confirm the high sensitivity and specificity of the iron superoxide dismutase antigen secreted by them, which may prove to be very useful in epidemiological studies. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. IgG responses to Anopheles gambiae salivary antigen gSG6 detect variation in exposure to malaria vectors and disease risk

    DEFF Research Database (Denmark)

    Stone, Will; Bousema, Teun; Jones, Sophie

    2012-01-01

    as the basis of an immuno-assay determining exposure to Afrotropical malaria vectors. In the present study, IgG responses to gSG6 and 6 malaria antigens (CSP, AMA-1, MSP-1, MSP-3, GLURP R1, and GLURP R2) were compared to Anopheles exposure and malaria incidence in a cohort of children from Korogwe district...... with subsequent malaria incidence (test for trend p¿=¿0.004), comparable to malaria antigens MSP-1 and GLURP R2. Our results show that the gSG6 assay is sensitive to micro-epidemiological variations in exposure to Anopheles mosquitoes, and provides a correlate of malaria risk that is unrelated to immune...

  11. Immunohistochemical detection of VHS virus in paraffin-embedded specimens of rainbow trout (Oncorhynchus mykiss); The influence of primary antibody, fixative, and antigen unmasking on method sensitivity

    DEFF Research Database (Denmark)

    Evensen, O.; Olesen, Niels Jørgen

    1997-01-01

    performed on parallel specimens, and the virus titer (TCID50/ml) was determined. Purified nucleocapsid protein (N-protein) of the virus was incorporated in an artificial antigen substrate (polymerized bovine serum albumin), fixed as described above, and embedded in paraffin wax. Microwave unmasking...... was performed an formalin-, PLP-, and Bouin's fluid-fixed specimens. The presence of virus peptides in situ or N-protein in the artificial antigen substrates was Visualized using an immunohistochemical method based on alkaline phosphatase or peroxidase and one polyclonal and five monoclonal polypeptide......-specific antibodies. VHS virus was identified in situ in specimens with high virus titers (10(7-8) TCID50/ml) regardless of the fixative and without the need of an unmasking procedure. A pronounced masking effect was observed for the cross-linking formalin and PLP fixatives. Regardless of the primary antibodies used...

  12. The prognostic value of oncogenic antigen 519 (OA-519) expression and proliferative activity detected by antibody MIB-1 in node-negative breast cancer

    DEFF Research Database (Denmark)

    Jensen, V; Ladekarl, M; Holm-Nielsen, P

    1995-01-01

    The prognostic value of oncogenic antigen 519 (OA-519) expression and tumour proliferative activity was evaluated in a retrospective series of 118 patients with low-risk breast cancer. Low risk was defined as negative axillary nodes, tumour diameter histological evidence...... analysis, both the MIB-1 index and OA-519 expression were of independent prognostic value (2p breast cancer who might benefit from adjuvant therapy....

  13. Utility of a stool antigen test to detect the incidence of helicobacter pylori infection and familial and community enviromental risk factors for this infection in pediatric age

    Directory of Open Access Journals (Sweden)

    T. Sabbi

    2012-04-01

    Full Text Available Background: helicobacter pylori (hp infection is mainly acquired during childhood; it is recognised as a cause of gastritis and peptic ulcer and it has been classified as a group A carcinogen by World health organization. the exact mode of transmission is as yet, not known. Aim of our study has been to identify risk factors associated with helicobacter pylori infection in a preschool and school population and to confirm if hp antigen in faeces is useful as screening in epidemiological studies. Methods: We interviewed, with questionnaire, 400 children (203 male; age range 3-10 years; mean age 6 years of 3 different schools and stool samples were collected of all children too. 35 of 400 (8% children underwent to upper gastrointestinal endoscopy because of a suspect of upper gastrointestinal disease. Results: stool were collected from 400 school children and 35 of them shown positivity of hp antigen test. A questionnaire about presence of nausea, vomit, recurrent abdominal pain, family size, parent’s occupations and education, use of antibiotics, country of birth of child and parents, personal hygiene, breast feeding, presence of the animals was completed. 35 children with positive hp stool antigen test and a suspicious of upper gastrointestinal disease (recurrent abdominal pain, diurnal or nocturnal abdominal pain, nausea, vomiting, iron deficiency underwent to esophagogastroduodenoscopy (egdS that demonstrated antral gastritis and positive histology and urease rapid test. Conclusions: the results of this study suggest that risk factors for hp infection are low socioeconomics factors, hygiene and living conditions and that hp antigen in faeces is useful as screening test.

  14. Usefulness of the detection of Toxoplasma gondii antigens in AIDS patients Utilidad de la detección de antígenos de Toxoplasma gondii en pacientes con SIDA

    Directory of Open Access Journals (Sweden)

    Alberto Fachado

    1994-12-01

    Full Text Available Toxoplasmic encephalitis (TE is a mayor cause of central nervous system infection in patients with acquired immunodeficiency syndrome (AIDS. Toxoplasma antibodies were detected in 56 of 79 patients with AIDS (71%, in the present study. Fourteen out of 57 seropositive patients developed TF (25% and had Toxoplasma gondii antigen detected in their urine. For this, most of them received an effective therapy, with the subsequent disappearance of the symptoms and discontinuity of excretion of the T. gondii antigens. Our results suggest that the monitoring of T. gondii antigen in the urine of AIDS patients may be useful to decide on the proper time for therapy, as well as to avoid the beginning of neurologic signs in these patients.La Encefalitis Toxoplásmica (ET es la más importante complicación infecciosa del Sistema Nervioso Central en pacientes de SIDA. Anticuerpos anti-Toxoplasma gondii fueron detectados en 57 de 79 pacientes de SIDA (71%. De estos seropositivos, desarrollaron la enfermedad (ET 14 (25%, en los que coincidentemente se detectó la presencia de antígeno del parásito en orina y por tanto fueron objeto de una terapia efectiva, con la subsecuente desaparición de los sintomas y de los antígenos excretados. Por los resultados del presente trabajo, consideramos lo útil de monitorear en estos pacientes la presencia de antígenos de T. gondii con el objetivo de aplicar oportunamente métodos quimoprofilácticos que eviten el surgimiento de manifestaciones neurológicas en estos pacientes.

  15. Detection of rabies antigen in the saliva and brains of apparently healthy dogs slaughtered for human consumption and its public health implications in abia state, Nigeria.

    Science.gov (United States)

    Mshelbwala, P P; Ogunkoya, A B; Maikai, B V

    2013-01-01

    The study was carried out in eight dogs slaughtering outlets within four Local Government Areas of the State for the determination of rabies antigen in the saliva and brain of apparently healthy dogs slaughtered for human consumption. A total of one hundred (100) samples each of saliva and brain were collected before and after slaughter, respectively, between April to June, 2013, in the selected areas. The saliva was subjected to rapid immune-chromatographic test (RICT) while direct fluorescent antibody test (DFAT) was carried out on the brain samples. Structured questionnaire was administered to nineteen (19) dog meat processors comprising 18 males and 1 female in the selected areas. Sixty four percent of the samples tested were from female dogs while 36% were from males, 5% tested positive for rabies antigen with the use of both tests; there was no statistical association between sex and rabies status of the dogs sampled (P > 0.05). Butchers bitten during the course of slaughtering were 94.7% out of which 72.8% utilized traditional method of treatment and only 27.8% reported to the hospital for proper medical attention. This study has established the presence of rabies antigen in apparently healthy dogs in the study area.

  16. Development of an indirect ELISA to detect Corynebacterium pseudotuberculosis specific antibodies in sheep employing T1 strain culture supernatant as antigen

    Directory of Open Access Journals (Sweden)

    Miriam F. Rebouças

    2013-11-01

    Full Text Available Corynebacterium pseudotuberculosis is the etiologic agent of caseous lymphadenitis (CLA, a chronic disease that affects goats and sheep, characterized by granuloma formation in subcutaneous and internal lymph nodes. CLA causes significant economic losses to commercial goat herds. In this study, we aimed to test secreted antigens secreted from T1 strain bacteria grown in brain heart infusion (BHI broth in an indirect ELISA system to determine the presence of specific immunoglobulins against C. pseudotuberculosis. We analyzed the BHI antigen electrophoretic profile and the recognition pattern by infected sheep sera samples. The ELISA results were compared with multiplex PCR assay and IFN-gamma production. The ELISA was able to discriminate between negative and positive animals, with a sensitivity of 89% and a specificity of 99%, using microbiological isolation as gold standard. When this assay was compared with multiplex PCR and specific IFN-gamma quantification, six discrepant results were found among thirty-two samples. We concluded that the ELISA using antigens secreted from C. pseudotuberculosis T1 strain growth in BHI broth culture can be used for the serodiagnosis of CLA in sheep.

  17. Differentiation of infection from vaccination in foot-and-mouth disease by the detection of antibodies to the non-structural proteins 3D, 3AB and 3ABC in ELISA using antigens expressed in baculovirus

    DEFF Research Database (Denmark)

    Sørensen, K.J.; Madsen, K.G.; Madsen, E.S.

    1998-01-01

    The baculovirus expression system was found to be efficient at expressing the 3D, the 3AB and the 3ABC non-structural proteins (NSP) of foot-and-mouth disease virus (FMDV) as antigens recognised by immune sera in ELISA. ELISA's using 3D, 3AB and 3ABC detected antibodies from day 8 and 10 after...... experimental infection of susceptible cattle and sheep and cattle remained seropositive for more than 395 days. The ELISA's detected antibodies against any of the seven serotypes of FMDV. The 3D ELISA was specific and precise and as sensitive as established ELISA's which measure antibody to structural proteins....... The assay may be used as a resource saving alternative to established ELISA's for the detection of antibodies against any of the seven serotypes. The 3AB and the 3ABC ELISA were also specific and precise. FMDV infected cattle could be differentiated from those that had been merely vaccinated as they gave...

  18. Evaluation of envelope glycoprotein E(rns) of an atypical bovine pestivirus as antigen in a microsphere immunoassay for the detection of antibodies against bovine viral diarrhea virus 1 and atypical bovine pestivirus.

    Science.gov (United States)

    Vijayaraghavan, Balaje; Xia, Hongyan; Harimoorthy, Rajiv; Liu, Lihong; Belák, Sándor

    2012-11-01

    Atypical bovine pestiviruses are related antigenically and phylogenetically to bovine viral diarrhea viruses (BVDV-1 and BVDV-2), and may cause the same clinical manifestations in animals. Glycoprotein E(rns) of an atypical bovine pestivirus Th/04_KhonKaen was produced in a baculovirus expression system and was purified by affinity chromatography. The recombinant E(rns) protein was used as an antigen in a microsphere immunoassay for the detection of antibodies against BVDV-1 and atypical bovine pestivirus. The diagnostic performance of the new method was evaluated by testing a total of 596 serum samples, and the assay was compared with enzyme-linked immunosorbent assay (ELISA). Based on the negative/positive cut-off median fluorescence intensity (MFI) value of 2800, the microsphere immunoassay had a sensitivity of 100% and specificity of 100% compared to ELISA. The immunoassay was able to detect antibodies against both BVDV-1 and the atypical pestivirus. This novel microsphere immunoassay has the potential to be multiplexed for simultaneous detection of antibodies against different bovine pathogens in a high-throughput and economical way. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. A late IL-33 response after exposure to Schistosoma haematobium antigen is associated with an up-regulation of IL-13 in human eosinophils

    DEFF Research Database (Denmark)

    Wilson, S.; Jones, F. M.; Fofana, H. K. M.

    2013-01-01

    IL-33, a proposed alarmin, stimulates innate immune cells and Th2 cells to produce IL-13 and is rapidly upregulated upon antigen exposure in murine helminth infection. The human IL-33 response to helminth antigen was analysed in Malians infected with Schistosoma haematobium by disrupting parasite...... integrity via chemotherapy. Plasma IL-33 was measured pretreatment, and 24 h and 9 weeks post-treatment. At 24 h post-treatment, IL-33 levels were low. Nine week post-treatment IL-33 levels were elevated and were associated with an increase in intracellular IL-13 in eosinophils. Up......-regulation of intracellular IL-13 in eosinophils was also associated with eosinophil expression of ST2L, the IL-33 receptor. IL-33 may play an important downstream role in the human response to schistosome adult worm antigen exposure....

  20. Accuracy of PfHRP2 versus Pf-pLDH antigen detection by malaria rapid diagnostic tests in hospitalized children in a seasonal hyperendemic malaria transmission area in Burkina Faso.

    Science.gov (United States)

    Maltha, Jessica; Guiraud, Issa; Lompo, Palpouguini; Kaboré, Bérenger; Gillet, Philippe; Van Geet, Chris; Tinto, Halidou; Jacobs, Jan

    2014-01-13

    In most sub-Saharan African countries malaria rapid diagnostic tests (RDTs) are now used for the diagnosis of malaria. Most RDTs used detect Plasmodium falciparum histidine-rich protein-2 (PfHRP2), though P. falciparum-specific parasite lactate dehydrogenase (Pf-pLDH)-detecting RDTs may have advantages over PfHRP2-detecting RDTs. Only few data are available on the use of RDTs in severe illness and the present study compared Pf-pLDH to PfHRP2-detection. Hospitalized children aged one month to 14 years presenting with fever or severe illness were included over one year. Venous blood samples were drawn for malaria diagnosis (microscopy and RDT), culture and complete blood count. Leftovers were stored at -80 °C and used for additional RDT analysis and PCR. An RDT targeting both PfHRP2 and Pf-pLDH was performed on all samples for direct comparison of diagnostic accuracy with microscopy as reference method. PCR was performed to explore false-positive RDT results. In 376 of 694 (54.2%) included children, malaria was microscopically confirmed. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value were 100.0, 70.9, 69.4 and 100.0%, respectively for PfHRP2-detection and 98.7, 94.0, 91.6 and 99.1%, respectively for Pf-pLDH-detection. Specificity and PPV were significantly lower for PfHRP2-detection (p <0.001). For both detection antigens, specificity was lowest for children one to five years and in the rainy season. PPV for both antigens was highest in the rainy season, because of higher malaria prevalence. False positive PfHRP2 results were associated with prior anti-malarial treatment and positive PCR results (98/114 (86.0%) samples tested). Among children presenting with severe febrile illness in a seasonal hyperendemic malaria transmission area, the present study observed similar sensitivity but lower specificity and PPV of PfHRP2 compared to Pf-pLDH-detection. Further studies should assess the diagnostic accuracy and safety of an

  1. Production of a conjugate between the rK346 antigen from Leishmania infantum and the horseradish peroxidase C for the detection of rK346 antibodies.

    Science.gov (United States)

    Rengifo-González, Juan; Medina-Mora, Yollyseth; Silva-Barrios, Sasha; Márquez-Contreras, María Elizabeth; Tibisay Ruiz, María; Cáceres, Ana J; Concepción, Juan Luis; Quiñones, Wilfredo

    2016-06-01

    It was designed and characterized a reporter system to be captured by an- tibodies bound to ELISA plates. The system was designed with the rK346 from Leishmania infantum, a highly antigenic and specific protein. The rK346 was coupled to the horseradish peroxidase C (HRPc) from Armoracia rusticana using glutaraldehyde or sulfo-SMCC. Gluta- raldehyde conjugation was performed in two steps. Separation of conjugates was carried out using a Sepharose S-200 in size exclusion chromatography (SEC); fractions were analyzed via HRPc activity and through ELISA plates sensitized with polyclonal anti-rK346 IgG puri- fied from rabbit serum. A heterogeneous population of conjugates rK346-HRPc was obtained with molecular weights ranging between 109.7 ± 16.5 to 67.6 ± 10.1 kDa; with rK346-HRPe stoichiometries of 1:2; 2:1; 3:1; and 2:2. Conjugation using sulfo-SMCC was carried out first by introducing -SH groups onto the HRPc using the SATA reagent and the antigen was modi- fied with sulfo-SMCC during 45 min. Separation and analysis of conjugates was performed similarly as with glutaraldehyde, resulting in a heterogeneous population of conjugates rK346- HRPc with molecular weights between 150.5 ± 22.6 to 80.0 ± 12.0 kDa; with rK346-HRPC stoichiometries of 2:1; 1:2; 2:2; and 1:3, with an increased conjugation efficiency in compari- son with glutaraldehyde. This enables sulfo-SMCC to be used as a potential reagent for cou- pling the antigen to the HRPc, to design an economic, specific and easy method to apply as a reporter system, available to assess individuals at risk and/or at early and late stages of visceral leishmaniasis.

  2. Using the AD12-ICT rapid-format test to detect Wuchereria bancrofti circulating antigens in comparison to Og4C3-ELISA and nucleopore membrane filtration and microscopy techniques.

    Science.gov (United States)

    El-Moamly, Amal Abdul-Rasheed; El-Sweify, Mohamed Aly; Hafez, Mohamad Abdul

    2012-09-01

    Lymphatic filariasis (LF) continues to be a major source of permanent disability and an impediment to socio-economic development in 73 countries where more than 1 billion people are at risk and over 120 millions are infected. The global drive to eliminate LF necessitates an increasing demand for valid, reliable and rapid diagnostic tests. This study aimed to assess the performance of the AD12 rapid format immunochromatographic test (ICT) to detect Wuchereria bancrofti circulating antigens, against the combined gold standard: TropBio Og4C3-ELISA (enzyme-linked immunosorbent assay) which detects circulating filarial antigen (CFA) and the nucleopore membrane filtration and microscopic examination. This prospective case-control study involved 647 asymptomatic migrant workers from filariasis-endemic countries. Of these specimens, 32 were positive for microfilaremia using the membrane filtration and microscopy, 142 positive by ELISA (of which 32 had microfilaremia), and 128 positive by the ICT (of which 31 had microfilaremia). The performance of the ICT was calculated against 32 true-positive and 90 true-negative cases. For the detection of CFA, the ICT had a sensitivity of 97% (95% confidence interval [CI] 91-103), specificity 100% (95% CI 100-100), Positive Predictive Value (PPV) 100% (95% CI 100-100), Negative Predictive Value (NPV) 99% (95% CI 97-101); and the total accuracy of the test was 99% (95% CI 98-101). The agreement between ICT and ELISA in detecting W. bancrofti antigens was excellent (kappa = 0.934; p = 0.000). In conclusion, the AD12-ICT test for the detection of W. bancrofti-CFA was sensitive and specific and comparable to the performance of ELISA. The ICT would be a useful additional test to facilitate the proposed strategies for control and elimination of LF. Because it is rapid, simple to perform, and does not require the use of special equipment, the ICT may be most appropriate in screening programs and in monitoring the possible risk of introducing

  3. Synthesis and evaluation of 1,4-naphthoquinone ether derivatives as SmTGR inhibitors and new anti-schistosomal drugs.

    Science.gov (United States)

    Johann, Laure; Belorgey, Didier; Huang, Hsin-Hung; Day, Latasha; Chessé, Matthieu; Becker, Katja; Williams, David L; Davioud-Charvet, Elisabeth

    2015-08-01

    Investigations regarding the chemistry and mechanism of action of 2-methyl-1,4-naphthoquinone (or menadione) derivatives revealed 3-phenoxymethyl menadiones as a novel anti-schistosomal chemical series. These newly synthesized compounds (1-7) and their difluoromethylmenadione counterparts (8, 9) were found to be potent and specific inhibitors of Schistosoma mansoni thioredoxin-glutathione reductase (SmTGR), which has been identified as a potential target for anti-schistosomal drugs. The compounds were also tested in enzymic assays using both human flavoenzymes, i.e. glutathione reductase (hGR) and selenium-dependent human thioredoxin reductase (hTrxR), to evaluate the specificity of the inhibition. Structure-activity relationships as well as physico- and electro-chemical studies showed a high potential for the 3-phenoxymethyl menadiones to inhibit SmTGR selectively compared to hGR and hTrxR enzymes, in particular those bearing an α-fluorophenol methyl ether moiety, which improves anti-schistosomal action. Furthermore, the (substituted phenoxy)methyl menadione derivative (7) displayed time-dependent SmTGR inactivation, correlating with unproductive NADPH-dependent redox cycling of SmTGR, and potent anti-schistosomal action in worms cultured ex vivo. In contrast, the difluoromethylmenadione analog 9, which inactivates SmTGR through an irreversible non-consuming NADPH-dependent process, has little killing effect in worms cultured ex vivo. Despite ex vivo activity, none of the compounds tested was active in vivo, suggesting that the limited bioavailability may compromise compound activity. Therefore, future studies will be directed toward improving pharmacokinetic properties and bioavailability. © 2015 FEBS.

  4. Effect of female genital schistosomiasis and anti-schistosomal treatment on monocytes, CD4+ T-cells and CCR5 expression in the female genital tract.

    Science.gov (United States)

    Kleppa, Elisabeth; Ramsuran, Veron; Zulu, Siphosenkosi; Karlsen, Gunn Hege; Bere, Alfred; Passmore, Jo-Ann S; Ndhlovu, Patricia; Lillebø, Kristine; Holmen, Sigve D; Onsrud, Mathias; Gundersen, Svein Gunnar; Taylor, Myra; Kjetland, Eyrun F; Ndung'u, Thumbi

    2014-01-01

    Schistosoma haematobium is a waterborne parasite that may cause female genital schistosomiasis (FGS), characterized by genital mucosal lesions. There is clinical and epidemiological evidence for a relationship between FGS and HIV. We investigated the impact of FGS on HIV target cell density and expression of the HIV co-receptor CCR5 in blood and cervical cytobrush samples. Furthermore we evaluated the effect of anti-schistosomal treatment on these cell populations. The study followed a case-control design with post treatment follow-up, nested in an on-going field study on FGS. Blood and cervical cytobrush samples were collected from FGS negative and positive women for flow cytometry analyses. Urine samples were investigated for schistosome ova by microscopy and polymerase chain reaction (PCR). FGS was associated with a higher frequency of CD14+ cells (monocytes) in blood (11.5% in FGS+ vs. 2.2% in FGS-, p = 0.042). Frequencies of CD4+ cells expressing CCR5 were higher in blood samples from FGS+ than from FGS- women (4.7% vs. 1.5%, p = 0.018). The CD14+ cell population decreased significantly in both compartments after anti-schistosomal treatment (p = 0.043). Although the frequency of CD4+ cells did not change after treatment, frequencies of CCR5 expression by CD4+ cells decreased significantly in both compartments (from 3.4% to 0.5% in blood, p = 0.036; and from 42.4% to 5.6% in genital samples, p = 0.025). The results support the hypothesis that FGS may increase the risk of HIV acquisition, not only through damage of the mucosal epithelial barrier, but also by affecting HIV target cell populations, and that anti-schistosomal treatment can modify this.

  5. Review of Mycobacteriumavium subsp. paratuberculosis antigen candidates with diagnostic potential

    DEFF Research Database (Denmark)

    Mikkelsen, Heidi; Aagaard, Claus; Nielsen, Søren Saxmose

    2011-01-01

    antigens, heat shock antigens and hypothetical antigens. Strategies for evaluation of novel antigen candidates are discussed critically. Relatively few of the described antigens were evaluated for their use in CMI based diagnostic assays and so far, no obvious candidate has been identified...... to development of antibodies and shedding of detectable amounts of MAP. At present, available diagnostic assays are limited by the lack of MAP specific antigens included in these assays resulting in poor specificity. The objective of this review is to provide a systematic overview of diagnostic MAP antigen...... faeces; however, these diagnostic tools are often not applicable until years after infection. Detection of MAP specific cell-mediated immune (CMI) responses can serve as an alternative and be implemented in a diagnostic tool. CMI responses can be measured at an early stage of infection, prior...

  6. Limited Value of Assays Using Detection of Immunoglobulin G Antibodies to the Two Recombinant Dense Granule Antigens, GRA1 and GRA6 Nt of Toxoplasma gondii, for Distinguishing between Acute and Chronic Infections in Pregnant Women

    Science.gov (United States)

    Ferrandiz, Josette; Mercier, Corinne; Wallon, Martine; Picot, Stéphane; Cesbron-Delauw, Marie-France; Peyron, François

    2004-01-01

    An enzyme-linked immunosorbent assay (ELISA) using two recombinant antigens of Toxoplasma gondii (GRA1 and GRA6 Nt) was developed in order to differentiate between pregnant women with a serological profile of recently acquired infection and those with chronic infection. Both proteins were expressed in Escherichia coli as glutathione S-transferase fusion proteins. Thirty-two serum samples from subjects who presented seroconversion within 3 months before sampling (group 1; acute profile), 46 serum samples from women who had a positive serology at least 1 year before sampling (group 2; chronic profile), and 100 serum samples from pregnant women who were not infected by T. gondii (group 3) were examined for immunoglobulin G (IgG) reactivity. For both antigens, the specificity reached 98%. In both groups of infected patients, the overall sensitivity scored was 60% for GRA1 and 83% for GRA6 Nt. In group 1, 34% of sera reacted with GRA1 whereas 84% of sera reacted with GRA6 Nt; in group 2, however, sensitivities were 78.2 and 82.6%, respectively. Combination of the readings obtained with both antigens yielded a sensitivity of 91%. A serological follow-up of 10 women who seroconverted during pregnancy displayed three different serological patterns: (i) a GRA profile paralleling the IgG curve, as detected by the commercial kit, (ii) a GRA1 profile, or (iii) GRA1 and GRA6 Nt profiles remaining negative for at least 8 weeks after the reference test gave positive results. Taken together, these results suggest that neither GRA1 nor GRA6 Nt is sensitive enough to be used routinely to differentiate between acute and chronic toxoplasmic infections. PMID:15539499

  7. Immunohistochemical detection of SWC3, CD2, CD3, CD4 and CD8 antigens in paraformaldehyde fixed and paraffin embedded porcine lymphoid tissue

    DEFF Research Database (Denmark)

    Tingstedt, Jens Erik; Tornehave, Ditte; Lind, Peter

    2003-01-01

    Identification of the different cell types of the immune system is important for in situ studies on the pathogenesis of infectious diseases in various animals, including the pig. Unfortunately, many monoclonal anti-leukocyte antibodies are only useful for staining frozen tissue sections with inhe......Identification of the different cell types of the immune system is important for in situ studies on the pathogenesis of infectious diseases in various animals, including the pig. Unfortunately, many monoclonal anti-leukocyte antibodies are only useful for staining frozen tissue sections...... with inherent poor tissue morphology, and are not readily adapted to formaldehyde fixed and paraffin embedded tissue with well preserved morphology. Seven well characterised monoclonal antibodies against porcine leukocyte antigens were tested on neutral buffered paraformaldehyde fixed and paraffin embedded...

  8. Comparison of standard and delayed imaging to improve the detection rate of [{sup 68}Ga]PSMA I and T PET/CT in patients with biochemical recurrence or prostate-specific antigen persistence after primary therapy for prostate cancer

    Energy Technology Data Exchange (ETDEWEB)

    Schmuck, Sebastian; Nordlohne, Stefan; Sohns, Jan M.; Ross, Tobias L.; Bengel, Frank M.; Derlin, Thorsten [Hannover Medical School, Department of Nuclear Medicine, Hannover (Germany); Klot, Christoph A. von [Hannover Medical School, Department of Urology and Urologic Oncology, Hannover (Germany); Henkenberens, Christoph; Christiansen, Hans [Hannover Medical School, Department of Radiation Oncology, Hannover (Germany); Wester, Hans-Juergen [Technische Universitaet Muenchen, Pharmaceutical Radiochemistry, Garching (Germany)

    2017-06-15

    The aim of this study was to assess the value of dual-time point imaging in PET/CT for detection of biochemically recurrent or persistent prostate cancer, using the prostate-specific membrane antigen (PSMA) ligand [{sup 68}Ga]PSMA I and T. 240 patients who underwent a [{sup 68}Ga]PSMA I and T PET/CT in the context of biochemical relapse of prostate cancer were included in this retrospective analysis. Imaging consisted of a standard whole-body PET/CT (1 h p.i.), followed by delayed (3 h p.i.) imaging of the abdomen. PSA-stratified proportions of positive PET/CT results, standardized uptake values and target-to-background ratios were analyzed, and compared between standard and delayed imaging. The overall detection rates of [{sup 68}Ga]PSMA I and T PET/CT were 94.2, 71.8, 58.6, 55.9 and 38.9% for PSA levels of ≥2, 1 to <2, 0.5 to <1, >0.2 to <0.5, and 0.01 to 0.2 ng/mL, respectively. Although the target-to-background ratio improved significantly over time (P < 0.0001), the majority (96.6%) of all lesions suggestive of recurrent disease could already be detected in standard imaging. Delayed imaging at 3 h p.i. exclusively identified pathologic findings in 5.4% (10/184) of abnormal [{sup 68}Ga]PSMA I and T PET/CT scans, and exclusively detected 3.4% (38/1134) of all lesions suggestive of recurrent disease. [{sup 68}Ga]PSMA I and T PET/CT shows high detection rates in patients with prostate-specific antigen persistence or biochemical recurrence of prostate cancer. Delayed imaging can detect lesions with improved contrast compared to standard imaging. However, the impact on detection rates was limited in this study. (orig.)

  9. A novel antibody–antigen based impedimetric immunosensor for low level detection of HER2 in serum samples of breast cancer patients via modification of a gold nanoparticles decorated multiwall carbon nanotube-ionic liquid electrode

    Energy Technology Data Exchange (ETDEWEB)

    Arkan, Elham [Nano Drug Delivery Research Center, Kermanshah University of Medical Sciences, Kermanshah (Iran, Islamic Republic of); Saber, Reza [Department of Medical Nanotechnology, School of Advanced Medical Technologies, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Research Center for Science and Technology in Medicine, Imam Khomeini Hospital, Tehran (Iran, Islamic Republic of); Karimi, Ziba [Department of Chemistry, Payame Noor University, P.O. Box 19395-3697, Tehran (Iran, Islamic Republic of); Shamsipur, Mojtaba, E-mail: mshamsipur@yahoo.com [Department of Chemistry, Razi University, Kermanshah (Iran, Islamic Republic of)

    2015-05-18

    Highlights: • Design of a novel impedimetric immunosensor for detection of HER2 in serum samples. • Use of a multiwall carbon nanotube-ionic liquid electrode modified with AuNPs as a base. • Immobilization of monoclonal HER2 antibody on AuNPs/MWCILE using 1,6-hexanedithiol as a cross linker. • Achieving linear dynamic range and limit of detection of 10–110 ng mL{sup −1} and 7.4 ng mL{sup −1}, respectively. • Method development and validation and application to assay of HER2 in biological fluids. - Abstract: A highly sensitive impedimetric immunosensor based on a gold nanoparticles/multiwall carbon nanotube-ionic liquid electrode (AuNPs/MW-CILE) was developed for the determination of human epidermal growth factor receptor 2 (HER2). Gold nanoparticles were used to enhance the extent of immobilization and to retain the immunoactivity of the antibody Herceptin on the electrode. Cyclic voltammetry and electrochemical impedance spectroscopy were employed for characterization of various layers coated onto the AuNPs/MW-CILE. The impedance measurements at different steps were based on the charge transfer kinetics of the [Fe(CN){sub 6}]{sup 3−/4−} redox pair. The immobilization of antibody and the corresponding antigen–antibody interaction at the electrode surface altered the interfacial electron transfer. The interactions of antibody with various concentrations of antigen were also monitored via the change of impedance response. The results showed that the charge transfer resistance increases linearly with increasing concentrations of HER2 antigen. The linear range and limit of detection were found as 10–110 ng mL{sup −1} and 7.4 ng mL{sup −1}, respectively. The sensitivity and specificity of the immunosensor were validated. The results showed that the prepared immunosensor is a useful tool for screening of trace amounts of HER2 in serum samples of breast cancer patients.

  10. Multiplex assay (Mikrogen recomBead) for detection of serum IgG and IgM antibodies to 13 recombinant antigens of Borrelia burgdorferi sensu lato in patients with neuroborreliosis

    DEFF Research Database (Denmark)

    Dessau, Ram Benny; Møller, Jens K.; Kolmos, Birte

    2015-01-01

    A multiplex-bead-based assay for the detection of serum antibodies to Borrelia burgdorferi sensu lato was evaluated. The assay contained 13 different antigens in both the IgG and the IgM assay; thus, a total of 26 measurement results were available from each sample. A total of 49 Danish patients......, the construction of a diagnostic score, evaluation of the scoring method using an independent dataset and an assessment of the analytical quality of the multiplex assay. The VlsE IgG had the highest diagnostic value with an AUC (area under the curve) of 96% on the receiver operating characteristic curve. The Osp......C IgM had AUCs just above 80%. All the other antigens had both low quantitative reactivity and lower contrast in the patients with LNB compared to controls. The diagnostic value of the assay may be improved by using a logistic model giving a sensitivity of 90 and 79% for the specificities at 92 and 98...

  11. Correlation of Serum and Dried Blood Spot Results for Quantitation of Schistosoma Circulating Anodic Antigen: a Proof of Principle

    Science.gov (United States)

    Downs, Jennifer A.; Corstjens, Paul L.A.M.; Mngara, Julius; Lutonja, Peter; Isingo, Raphael; Urassa, Mark; Kornelis, Dieuwke; van Dam, Govert J.

    2015-01-01

    Circulating Anodic Antigen (CAA) testing is a powerful, increasingly-used tool for diagnosis of active schistosome infection. We sought to determine the feasibility and reliability of measuring CAA in blood spots collected on Whatman 903 Protein Saver cards, which are the predominant filter papers used worldwide for dried blood spot (DBS) research and clinical care. CAA was eluted from blood spots collected from 19 individuals onto Whatman 903 cards in Mwanza, Tanzania, and the assay was optimized to achieve CAA ratios comparable to those obtained from the spots’ corresponding serum samples. The optimized assay was then used to determine the correlation of serum samples (n=16) with DBS from cards that had been stored for 8 years at ambient temperature.Using a DBS volume equivalent to approximately four times the quantity of serum, CAA testing in DBS had a sensitivity of 76% and a specificity of 79% compared to CAA testing in serum. CAA testing was reliable in samples eluted from Whatman 903 cards that had been stored for 8 years at ambient temperature. The overall kappa coefficient was 0.53 (standard error 0.17, p<0.001). We conclude that CAA can be reliably and accurately measured in DBS collected onto the filter paper that is most commonly used for clinical care and research, and that can be stored for prolonged periods of time. This finding opens new avenues for future work among more than 700 million individuals living in areas worldwide in which schistosomes are endemic. PMID:26149541

  12. Treatment of Schistosoma mansoni with miltefosine in vitro enhances serological recognition of defined worm surface antigens.

    Directory of Open Access Journals (Sweden)

    Marwa H El-Faham

    2017-08-01

    Full Text Available Miltefosine, an anti-cancer drug that has been successfully repositioned for treatment of Leishmania infections, has recently also shown promising effects against Schistosoma spp targeting all life cycle stages of the parasite. The current study examined the effect of treating Schistosoma mansoni adult worms with miltefosine on exposure of worm surface antigens in vitro.In an indirect immunofluorescence assay, rabbit anti-S.mansoni adult worm homogenate and anti-S. mansoni infection antisera gave strong immunofluorescence of the S. mansoni adult worm surface after treatment with miltefosine, the latter antiserum having previously been shown to synergistically enhance the schistosomicidal activity of praziquantel. Rabbit antibodies that recognised surface antigens exposed on miltefosine-treated worms were recovered by elution off the worm surface in low pH buffer and were used in a western immunoblotting assay to identify antigenic targets in a homogenate extract of adult worms (SmWH. Four proteins reacting with the antibodies in immunoblots were purified and proteomic analysis (MS/MS combined with specific immunoblotting indicated they were the S. mansoni proteins: fructose-1,6 bisphosphate aldolase (SmFBPA, Sm22.6, alkaline phosphatase and malate dehydrogenase. These antibodies were also found to bind to the surface of 3-hour schistosomula and induce immune agglutination of the parasites, suggesting they may have a role in immune protection.This study reveals a novel mode of action of miltefosine as an anti-schistosome agent. The immune-dependent hypothesis we investigated has previously been lent credence with praziquantel (PZQ, whereby treatment unmasks parasite surface antigens not normally exposed to the host during infection. Antigens involved in this molecular mechanism could have potential as intervention targets and antibodies against these antigens may act to increase the drug's anti-parasite efficacy and be involved in the development

  13. Expression profile of the Schistosoma japonicum degradome reveals differential protease expression patterns and potential anti-schistosomal intervention targets.

    Directory of Open Access Journals (Sweden)

    Shuai Liu

    2014-10-01

    Full Text Available Blood fluke proteases play pivotal roles in the processes of invasion, nutrition acquisition, immune evasion, and other host-parasite interactions. Hundreds of genes encoding putative proteases have been identified in the recently published schistosome genomes. However, the expression profiles of these proteases in Schistosoma species have not yet been systematically analyzed. We retrieved and culled the redundant protease sequences of Schistosoma japonicum, Schistosoma mansoni, Echinococcus multilocularis, and Clonorchis sinensis from public databases utilizing bioinformatic approaches. The degradomes of the four parasitic organisms and Homo sapiens were then comparatively analyzed. A total of 262 S. japonicum protease sequences were obtained and the expression profiles generated using whole-genome microarray. Four main clusters of protease genes with different expression patterns were identified: proteases up-regulated in hepatic schistosomula and adult worms, egg-specific or predominantly expressed proteases, cercaria-specific or predominantly expressed proteases, and constantly expressed proteases. A subset of protease genes with different expression patterns were further validated using real-time quantitative PCR. The present study represents the most comprehensive analysis of a degradome in Schistosoma species to date. These results provide a firm foundation for future research on the specific function(s of individual proteases and may help to refine anti-proteolytic strategies in blood flukes.

  14. Four whole-istic aspects of schistosome granuloma biology: fractal arrangement, internal regulation, autopoietic component and closure

    Directory of Open Access Journals (Sweden)

    HL Lenzi

    2006-10-01

    Full Text Available This paper centers on some whole-istic organizational and functional aspects of hepatic Schistosoma mansoni granuloma, which is an extremely complex system. First, it structurally develops a collagenic topology, originated bidirectionally from an inward and outward assembly of growth units. Inward growth appears to be originated from myofibroblasts derived from small portal vessel around intravascular entrapped eggs, while outward growth arises from hepatic stellate cells. The auto-assembly of the growth units defines the three-dimensional scaffold of the schistosome granulomas. The granuloma surface irregularity and its border presented fractal dimension equal to 1.58. Second, it is internally regulated by intricate networks of immuneneuroendocrine stimuli orchestrated by leptin and leptin receptors, substance P and Vasoactive intestinal peptide. Third, it can reach the population of ± 40,000 cells and presents an autopoietic component evidenced by internal proliferation (Ki-67+ Cells, and by expression of c-Kit+ Cells, leptin and leptin receptor (Ob-R, granulocyte-colony stimulating factor (G-CSF-R, and erythropoietin (Epo-R receptors. Fourth, the granulomas cells are intimately connected by pan-cadherins, occludin and connexin-43, building a state of closing (granuloma closure. In conclusion, the granuloma is characterized by transitory stages in such a way that its organized structure emerges as a global property which is greater than the sum of actions of its individual cells and extracellular matrix components.

  15. The use of enzyme-linked immunosorbent assay systems for the serology and antigen detection in parvovirus, coronavirus and rotavirus infections in dogs in The Netherlands.

    NARCIS (Netherlands)

    G.F. Rimmelzwaan (Guus); J. Groen (Jan); H.F. Egberink (Herman); G.H.A. Borst (Gerrit); F.G.C.M. Uytdehaag (Fons); A.D.M.E. Osterhaus (Albert)

    1991-01-01

    textabstractComplex trapping blocking (CTB) enzyme-linked immunosorbent assays (ELISAs) and indirect ELISAs for the detection of antibodies to canine parvovirus (CPV), canine coronavirus (CCV) and rotavirus in sera of dogs were established. Double antibody sandwich ELISAs for the detection of CPV-,

  16. Development of myiasis vaccine: In vitro detection of immunoprotective responses of peritrophic membrane protein, first instar larva Ll supernatant and pellet antigen of fly Chrysomyia bezziana in sheep

    Directory of Open Access Journals (Sweden)

    Sukarsih

    1999-10-01

    Full Text Available Myiasis control by means of individual treatment of animals which are mainly rised extensively is time consumed and expensive. The alternative way to control this disease by vaccination is considered effective and economically accepted. However the expected vaccine is now still being developed under a collaborative project between CSIRO, Inter-University Centre on Biotechnology-ITB and Research Institute for Veterinary Science and funded by ACIAR. There are several antigens have been identified as vaccine candidates and an in vitro bioassay technique has been developed for assessing the immunoresponses of vaccine in sheep. Three antigens were used for vaccines in this study, these included protein peritrophic membrane (PM, soluble extract (SE and pellet extract (PE of 1st instar larvae of Chrysomya bezziana. Twenty four experimental sheep were divided into 4 groups of 6 animals, 3 groups of animals were injected with PM, SE and PE vaccines with the dose rate of 0.5 g PM/head, 0.8 g PE/head and 4.2 ml LE/head respectively, and the other one group was injected with 4 ml PBS/head as a control group. Vaccination with the same dose was repeated 4 weeks after the 1st vaccination as a booster, and 2 weeks after the booster the sheep were challenged with live larvae, 3 days after challenge animals were killed. Sera were collected at the day of vaccination, 4 weeks after vaccination, 2 weeks after booster, and 3 days after challenge. An in vitro bioassay technique was conducted by culturing 1st instar larvae on five media containing sera collected from each experimental animal. The effects of sera on cultivated larvae were assessed by means of larval weight and larval mortality rate. The results indicated that the growth rate and survival of cultivated larvae in media containing anti-PM sera were significantly lower (P<0.01 compared to the larvae cultivated on media with sera on the day of vaccination. The larval weight depression by anti- PM sera

  17. Canine Distemper Virus Antigen Detection in External Epithelia of Recently Vaccinated, Sick Dogs by Fluorescence Microscopy Is a Valuable Prognostic Indicator

    Science.gov (United States)

    Neel, Tina

    2014-01-01

    Currently, there are no reliable predictors of the clinical outcomes of domesticated dogs that have been recently vaccinated against canine distemper virus (CDV) and develop respiratory disease. In this study, vaccinated dogs from Oklahoma City that were showing clinical signs of respiratory disease were evaluated for CDV antigen using a direct fluorescent antibody test (FAT). Clinical outcomes after standard symptomatic therapy for respiratory disease were recorded, and a statistical analysis of the results was performed. We present our study showing that CDV FAT results were predictive of clinical recovery (prognostic indicator, prospects of clinical recovery) among vaccinated dogs showing clinical signs of respiratory disease. Negative CDV FAT results equated to 80% chances of recovery after symptomatic therapy, compared to 55% chances of recovery when the CDV FAT results were positive. Based on the results of this study, we show that veterinarians can make better informed decisions about the clinical outcomes of suspected CDV cases, with 2-h turnaround times, by using the CDV FAT. Thus, antemortem examination with the CDV FAT on external epithelia of recently vaccinated, sick dogs is a clinically useful diagnostic test and valuable prognostic indicator for veterinarians. Application of the CDV FAT to these samples avoids unnecessary euthanasia of dogs with suspected CDV. PMID:25428156

  18. Canine distemper virus antigen detection in external epithelia of recently vaccinated, sick dogs by fluorescence microscopy is a valuable prognostic indicator.

    Science.gov (United States)

    Kapil, Sanjay; Neel, Tina

    2015-02-01

    Currently, there are no reliable predictors of the clinical outcomes of domesticated dogs that have been recently vaccinated against canine distemper virus (CDV) and develop respiratory disease. In this study, vaccinated dogs from Oklahoma City that were showing clinical signs of respiratory disease were evaluated for CDV antigen using a direct fluorescent antibody test (FAT). Clinical outcomes after standard symptomatic therapy for respiratory disease were recorded, and a statistical analysis of the results was performed. We present our study showing that CDV FAT results were predictive of clinical recovery (prognostic indicator, prospects of clinical recovery) among vaccinated dogs showing clinical signs of respiratory disease. Negative CDV FAT results equated to 80% chances of recovery after symptomatic therapy, compared to 55% chances of recovery when the CDV FAT results were positive. Based on the results of this study, we show that veterinarians can make better informed decisions about the clinical outcomes of suspected CDV cases, with 2-h turnaround times, by using the CDV FAT. Thus, antemortem examination with the CDV FAT on external epithelia of recently vaccinated, sick dogs is a clinically useful diagnostic test and valuable prognostic indicator for veterinarians. Application of the CDV FAT to these samples avoids unnecessary euthanasia of dogs with suspected CDV. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  19. Asymptomatic cryptococcal antigen prevalence detected by lateral flow assay in hospitalised HIV-infected patients in São Paulo, Brazil.

    Science.gov (United States)

    Vidal, José E; Toniolo, Carolina; Paulino, Adriana; Colombo, Arnaldo; Dos Anjos Martins, Marilena; da Silva Meira, Cristina; Pereira-Chioccola, Vera Lucia; Figueiredo-Mello, Claudia; Barros, Tiago; Duarte, Jequelie; Fonseca, Fernanda; Alves Cunha, Mirella; Mendes, Clara; Ribero, Taiana; Dos Santos Lazera, Marcia; Rajasingham, Radha; Boulware, David R

    2016-12-01

    To determine the prevalence of asymptomatic cryptococcal antigen (CRAG) using lateral flow assay (LFA) in hospitalised HIV-infected patients with CD4 counts 18 years old without prior cryptococcal meningitis, without clinical suspicion of cryptococcal meningitis, regardless of antiretroviral (ART) status, and with CD4 counts <200 cells/μl. Serum CRAG was tested by LFA in all patients, and whole blood CRAG was tested by LFA in positive cases. We enrolled 163 participants of whom 61% were men. The duration of HIV diagnosis was a median of 8 (range, 1-29) years. 26% were antiretroviral (ART)-naïve, and 74% were ART-experienced. The median CD4 cell count was 25 (range, 1-192) cells/μl. Five patients (3.1%; 95%CI, 1.0-7.0%) were asymptomatic CRAG-positive. Positive results cases were cross-verified by performing LFA in whole blood. 3.1% of HIV-infected inpatients with CD4 <200 cells/μl without symptomatic meningitis had cryptococcal antigenemia in São Paulo, suggesting that routine CRAG screening may be beneficial in similar settings in South America. Our study reveals another targeted population for CRAG screening: hospitalised HIV-infected patients with CD4 <200 cells/μl, regardless of ART status. Whole blood CRAG LFA screening seems to be a simple strategy to prevention of symptomatic meningitis. © 2016 John Wiley & Sons Ltd.

  20. Detection of Serum Thermolabile β-2 Macroglycoprotein (Hakata Antigen) by Enzyme-Linked Immunosorbent Assay Using Polysaccharide Produced by Aerococcus viridans

    Science.gov (United States)

    Tsujimura, Mitsushi; Ishida, Chuzo; Sagara, Yasuko; Miyazaki, Takashi; Murakami, Koichi; Shiraki, Hiroshi; Okochi, Kazuo; Maeda, Yoshiaki

    2001-01-01

    Although a serum thermolabile β-2 macroglycoprotein (TMG) may play a role in host defense as a lectin, little is known of its related physiological functions, mainly due to a lack of appropriate methods for tracing the functions of TMG. We identified a polysaccharide from Aerococcus viridans, PSA, which reacts with TMG, and based on this finding, we developed an enzyme-linked immunosorbent assay to trace the functions of TMG. Using ethanol precipitation and DEAE-Sepharose and Sephacryl S-400 column chromatographies, we isolated PSA from cultured medium of A. viridans, and it exhibited specific binding against TMG in blood samples. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), the isolated PSA showed ladder bands that implied the existence of repeating units composed of d-glucose, N-acetyl-d-glucosamine, d-mannose, and d-xylose, as confirmed by gas chromatography-mass spectrometry. SDS-PAGE and immunochemical analysis, using rabbit anti-TMG antibody, showed that PSA specifically binds solely to intact serum TMG but not to TMG heated at 56°C for 30 min, a condition under which antigenicity is lost. TMG in serum samples bound to PSA in a dose-dependent manner, and this binding was clearly suppressed by addition of PSA. These observations indicate that PSA is a useful adsorbent to TMG and can be used to develop appropriate methods for tracing the functions of TMG. PMID:11238239

  1. Enterovirus 71 encephalomyelitis and Japanese encephalitis can be distinguished by topographic distribution of inflammation and specific intraneuronal detection of viral antigen and RNA.

    Science.gov (United States)

    Wong, K T; Ng, K Y; Ong, K C; Ng, W F; Shankar, S K; Mahadevan, A; Radotra, B; Su, I J; Lau, G; Ling, A E; Chan, K P; Macorelles, P; Vallet, S; Cardosa, M J; Desai, A; Ravi, V; Nagata, N; Shimizu, H; Takasaki, T

    2012-08-01

    To investigate if two important epidemic viral encephalitis in children, Enterovirus 71 (EV71) encephalomyelitis and Japanese encephalitis (JE) whose clinical and pathological features may be nonspecific and overlapping, could be distinguished. Tissue sections from the central nervous system of infected cases were examined by light microscopy, immunohistochemistry and in situ hybridization. All 13 cases of EV71 encephalomyelitis collected from Asia and France invariably showed stereotyped distribution of inflammation in the spinal cord, brainstem, hypothalamus, cerebellar dentate nucleus and, to a lesser extent, cerebral cortex and meninges. Anterior pons, corpus striatum, thalamus, temporal lobe, hippocampus and cerebellar cortex were always uninflamed. In contrast, the eight JE cases studied showed inflammation involving most neuronal areas of the central nervous system, including the areas that were uninflamed in EV71 encephalomyelitis. Lesions in both infections were nonspecific, consisting of perivascular and parenchymal infiltration by inflammatory cells, oedematous/necrolytic areas, microglial nodules and neuronophagia. Viral inclusions were absent. Immunohistochemistry and in situ hybridization assays were useful to identify the causative virus, localizing viral antigens and RNA, respectively, almost exclusively to neurones. The stereotyped distribution of inflammatory lesions in EV71 encephalomyelitis appears to be very useful to help distinguish it from JE. © 2011 The Authors. Neuropathology and Applied Neurobiology © 2011 British Neuropathological Society.

  2. Antigen retrieval, blocking, detection and visualisation systems in immunohistochemistry: a review and practical evaluation of tyramide and rolling circle amplification systems.

    Science.gov (United States)

    Warford, Anthony; Akbar, Hameed; Riberio, Deise

    2014-11-01

    To achieve specificity and sensitivity using immunohistochemistry it is necessary to combine the application of validated primary antibodies with optimised pre-treatment, detection and visualisation steps. The influence of these surrounding procedures is reviewed. A practical evaluation of tyramide signal amplification and rolling circle amplification detection methods is provided in which formalin fixed paraffin embedded sections of adenocarcinomas of breast, colon and lung together with squamous metaplasia of lung were immunostained with CD20 and CK19 primary antibodies. The results indicate that the detection systems are of comparable sensitivity and specificity. Copyright © 2014 Elsevier Inc. All rights reserved.

  3. Comparison of electron microscopy, enzyme-linked immunosorbent assay, solid-phase radioimmunoassay, and indirect immunofluorescence for detection of human rotavirus antigen in faeces

    Energy Technology Data Exchange (ETDEWEB)

    Birch, C J; Lehmann, N I; Hawker, A J; Marshall, J A; Gust, I D [Fairfield Hospital for Communicable Diseases, Victoria (Australia). Virology Dept.

    1979-07-01

    Four techniques were compared for their practicability, speed, and sensitivity for the detection of human rotavirus. Radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA) were found to be the most sensitive means of identifying rotavirus and, once processed, up to 40 specimens could be examined daily. Electron microscopy, although less sensitive than these techniques, had the advantage of being able to detect other viral agents present in faecal extracts. Indirect immunofluorescence failed to detect rotavirus as often as the other three methods. In laboratories where routine examination of faecal specimens from patients with gastroenteritis is required, ELISA and RIA are useful alternatives to electron microscopy.

  4. Comparison of electron microscopy, enzyme-linked immunosorbent assay, solid-phase radioimmunoassay, and indirect immunofluorescence for detection of human rotavirus antigen in faeces

    International Nuclear Information System (INIS)

    Birch, C.J.; Lehmann, N.I.; Hawker, A.J.; Marshall, J.A.; Gust, I.D.

    1979-01-01

    Four techniques were compared for their practicability, speed, and sensitivity for the detection of human rotavirus. Radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA) were found to be the most sensitive means of identifying rotavirus and, once processed, up to 40 specimens could be examined daily. Electron microscopy, although less sensitive than these techniques, had the advantage of being able to detect other viral agents present in faecal extracts. Indirect immunofluorescence failed to detect rotavirus as often as the other three methods. In laboratories where routine examination of faecal specimens from patients with gastroenteritis is required, ELISA and RIA are useful alternatives to electron microscopy. (author)

  5. Tumor markers in the early detection of tumor recurrence in breast cancer patients: CA 125, CYFRA 21-1, HER2 shed antigen, LDH and CRP in combination with CEA and CA 15-3.

    Science.gov (United States)

    Di Gioia, Dorit; Blankenburg, Irene; Nagel, Dorothea; Heinemann, Volker; Stieber, Petra

    2016-10-01

    Kinetics of CA 15-3 and CEA have a high specificity in the early detection of metastatic breast cancer (MBC). However, this high specificity is associated with a lack of sensitivity. To decrease the number of false negative patients, the additional diagnostic potential of an extended panel of biomarkers was evaluated. This analysis was performed as part of a large follow-up study (1998-2010) evaluating 813 patients with a median follow-up of 63months. After primary therapy, all patients underwent tumor marker monitoring for CEA and CA 15-3 at 6-week intervals. A reproducible previously defined increase (≥100%) based on the individual baseline value of each patient was considered as a strong indicator of MBC. For the present analysis, we retrospectively evaluated 1011 blood samples from 95 patients. Forty-seven of these had metastatic disease for the first time at the time of this evaluation, while the remaining 48 patients showed no evidence of disease. The sera of these patients were additionally assessed for the following parameters: cancer antigen (CA) 125, cytokeratin-19 soluble fragment (CYFRA 21-1), HER2 shed antigen, lactate-dehydrogenase (LDH) and C-reactive protein (CRP). 26 of 47 patients with MBC showed a reproducible tumor marker increase of at least CEA and/or CA 15-3 (55.3%, true-positive). The remaining 21 patients with MBC showed no increase in CEA or CA 15-3 (44.7%, false negative, FN). By combining all markers mentioned above, 41 of 47 patients with MBC showed a reproducible marker increase with a sensitivity of 87.2% and specificity of 100%. This retrospective analysis indicates that a panel of biomarkers can increase the sensitivity of the CA 15-3/CEA combination without loss of specificity. The combined use is therefore helpful for early detection of MBC. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Coombs Antiglobulin Test Using Brucella abortus 99 as Antigen To Detect Incomplete Antibodies Induced by B. abortus RB51 Vaccine in Cattle

    OpenAIRE

    Ciuchini, Franco; Adone, Rosanna; Pasquali, Paolo

    2002-01-01

    This study showed that vaccination of cattle with Brucella abortus rough strain RB51 induces incomplete antibodies that can be detectable by a Coombs antiglobulin test using the B. abortus 99 smooth strain.

  7. Expression and Antigenic Evaluation of VacA Antigenic Fragment of Helicobacter Pylori

    Science.gov (United States)

    Hasanzadeh, Leila; Ghaznavi-Rad, Ehsanollah; Soufian, Safieh; Farjadi, Vahideh; Abtahi, Hamid

    2013-01-01

    Objective(s) : Helicobacter pylori, a human specific gastric pathogen is a causative agent of chronic active gastritis. The vacuolating cytotoxin (VacA) is an effective virulence factor involved in gastric injury. The aim of this study was to construct a recombinant protein containing antigenic region of VacA gene and determine its antigenicity. Materials and Methods: The antigenic region of VacA gene was detected by bioinformatics methods. The polymerase chain reaction method was used to amplify a highly antigenic region of VacA gene from chromosomal DNA of H. pylori. The eluted product was cloned into the prokaryotic expression vector pET32a. The target protein was expressed in the Escherichia coli BL21 (DE3) pLysS. The bacteria including pET32a-VacA plasmids were induced by IPTG. The antigenicity was finally studied by western blotting using sera of 15 H. pylori infected patients after purification. Results: Enzyme digestion analysis, PCR and DNA sequencing results showed that the target gene was inserted correctly into the recombinant vector. The expressed protein was purified successfully via affinity chromatography. Data indicated that antigenic region of VacA protein from Helicobacter pylori was recognized by all 15 patient’s sera. Conclusion : Our data showed that antigenic region of VacA protein can be expressed by in E. co.li. This protein was recognized by sera patients suffering from H. pylori infection. the recombinant protein has similar epitopes and close antigenic properties to the natural form of this antigen. Recombinant antigenic region of VacA protein also seems to be a promising antigen for protective and serologic diagnosis . PMID:23997913

  8. Expression and Antigenic Evaluation of VacA Antigenic Fragment of Helicobacter Pylori

    Directory of Open Access Journals (Sweden)

    Leila Hasanzadeh

    2013-07-01

    Full Text Available Objective(s: Helicobacter pylori, a human specific gastric pathogen is a causative agent of chronic active gastritis. The vacuolating cytotoxin (VacA is an effective virulence factor involved in gastric injury. The aim of this study was to construct a recombinant protein containing antigenic region of VacA gene and determine its antigenicity.   Materials and Methods: The antigenic region of VacA gene was detected by bioinformatics methods. The polymerase chain reaction method was used to amplify a highly antigenic region of VacA gene from chromosomal DNA of H. pylori. The eluted product was cloned into the prokaryotic expression vector pET32a. The target protein was expressed in the Escherichia coli BL21 (DE3 pLysS. The bacteria including pET32a-VacA plasmids were induced by IPTG. The antigenicity was finally studied by western blotting using sera of 15 H. pylori infected patients after purification. Results: Enzyme digestion analysis, PCR and DNA sequencing results showed that the target gene was inserted correctly into the recombinant vector. The expressed protein was purified successfully via affinity chromatography. Data indicated that antigenic region of VacA protein from Helicobacter pylori was recognized by all 15 patient’s sera. Conclusion : Our data showed that antigenic region of VacA protein can be expressed by in E. co.li. This protein was recognized by sera patients suffering from H. pylori infection. the recombinant protein has similar epitopes and close antigenic properties to the natural form of this antigen. Recombinant antigenic region of VacA protein also seems to be a promising antigen for protective and serologic diagnosis .

  9. Expression of Hepatitis B virus surface antigen (HBsAg from genotypes A, D and F and influence of amino acid variations related or not to genotypes on HBsAg detection

    Directory of Open Access Journals (Sweden)

    Natalia M. Araujo

    Full Text Available The impact of hepatitis B virus (HBV genotypes on the sensitivity of surface antigen (HBsAg detection assays has been poorly investigated. Here, plasmids carrying consensus or variant coding sequences for HBV surface proteins from genotypes A, D and F, were constructed. HBsAg levels were evaluated in medium and extracts of transfected CHO cells by a commercial polyclonal-based assay. We show that HBsAg detection values of consensus forms from genotypes D and F were, respectively, 37% and 30% lower than those obtained by genotype A. However, the presence of two single variations, T143M in genotype A, and T125M in genotype D, produced a decrease of 44% and an increase of 34%, respectively, on HBsAg mean values in comparison with their consensus forms. In conclusion, HBsAg detection levels varied among HBV genotypes. However, unique amino acid substitutions not linked to genotypes, such as T125M and T143M described here, should have more implications in HBV immunological diagnostics than the set of variations characteristic of each HBV genotype.

  10. Soluble CD30 and ELISA-detected human leukocyte antigen antibodies for the prediction of acute rejection in pediatric renal transplant recipients.

    Science.gov (United States)

    Billing, Heiko; Sander, Anja; Süsal, Caner; Ovens, Jörg; Feneberg, Reinhard; Höcker, Britta; Vondrak, Karel; Grenda, Ryszard; Friman, Stybjorn; Milford, David V; Lucan, Mihai; Opelz, Gerhard; Tönshoff, Burkhard

    2013-03-01

    Biomarker-based post-transplant immune monitoring for the prediction of impending graft rejection requires validation in specific patient populations. Serum of 28 pediatric renal transplant recipients within the framework of a well-controlled prospective randomized trial was analyzed pre- and post-transplant for soluble CD30 (sCD30), a biomarker reflecting mainly T-cell reactivity, and anti-human leukocyte antigen (anti-HLA) antibody reactivity, a biomarker for B-cell activation. A sCD30 concentration ≥40.3 U/ml on day 14 was able to discriminate between patients with or without biopsy-proven acute rejection (BPAR) with a sensitivity of 100% and a specificity of 76%. Six of seven patients (86%) with BPAR showed a sCD30 above this cut-off, whereas only 3/21 patients (14%) without BPAR had a sCD30 above this cut-off (P = 0.004). For pre- and post-transplant anti-HLA class II reactivities by enzyme-linked immunosorbent assay, a cut-off value of 140 optical density was able to discriminate rejecters from nonrejecters with a sensitivity of 86% or 71% and a specificity of 81% or 90%, respectively. Withdrawal of steroids was associated with a approximately twofold higher serum sCD30 compared to controls, but did not affect anti-HLA reactivities. An increased post-transplant sCD30 serum concentration and positive pre- and post-transplant anti-HLA class II reactivities are informative biomarkers for impending BPAR in pediatric renal transplant recipients. (TWIST, Clinical Trial No: FG-506-02-43). © 2012 The Authors Transplant International © 2012 European Society for Organ Transplantation. Published by Blackwell Publishing Ltd.

  11. Pathological analysis, detection of antigens, FasL expression analysis and leucocytes survival analysis in tilapia (Oreochromis niloticus) after infection with green fluorescent protein labeled Streptococcus agalactiae.

    Science.gov (United States)

    Wang, Jingyuan; Wu, Jinying; Yi, Liyuan; Hou, Zengxin; Li, Wensheng

    2017-03-01

    The pathogenesis of Streptococcus agalactiae infection in tilapia has not been fully described. To understand this, we investigated the clinic-pathological features of acute experimental septicemia in tilapia (Oreochromis niloticus) after receiving an intra-peritoneal injection with S. agalactiae THN-1901GFP. Immunohistochemistry and sections of pathological tissues were used to estimate the level of damage in the head-kidney, liver, spleen and trunk-kidney. The expression of FasL was analyzed by western blotting in these samples based on their damage levels. Leucocytes were isolated from the head-kidney and incubated with S. agalactiae THN-1901GFP. Then, phagocytosis, programmed cell death and the expression of FasL were analyzed. The infected tissues showed varying degrees of necrosis and histolysis. The serous membrane of the intestine was dissolved by S. agalactiae THN-1901GFP. Antigens of S. agalactiae THN-1901GFP accumulated in different parts of the infected organs. In the head-kidney and spleen, the expression of FasL was up-regulated in parallel with increased tissue damage. After being incubated with S. agalactiae THN-1901GFP, the phagocytic capacity and ability were both very high and the expression of FasL remained high in leucocytes. S. agalactiae THN-1901GFP was able to survive for a long period of time after being engulfed by phagocytic cells. These findings offer insight into the pathogenesis of S. agalactiae infection in tilapia. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Development and validation of a quantitative, high-throughput, fluorescent-based bioassay to detect schistosoma viability.

    Directory of Open Access Journals (Sweden)

    Emily Peak

    2010-07-01

    Full Text Available Schistosomiasis, caused by infection with the blood fluke Schistosoma, is responsible for greater than 200,000 human deaths per annum. Objective high-throughput screens for detecting novel anti-schistosomal targets will drive 'genome to drug' lead translational science at an unprecedented rate. Current methods for detecting schistosome viability rely on qualitative microscopic criteria, which require an understanding of parasite morphology, and most importantly, must be subjectively interpreted. These limitations, in the current state of the art, have significantly impeded progress into whole schistosome screening for next generation chemotherapies.We present here a microtiter plate-based method for reproducibly detecting schistosomula viability that takes advantage of the differential uptake of fluorophores (propidium iodide and fluorescein diacetate by living organisms. We validate this high-throughput system in detecting schistosomula viability using auranofin (a known inhibitor of thioredoxin glutathione reductase, praziquantel and a range of small compounds with previously-described (gambogic acid, sodium salinomycin, ethinyl estradiol, fluoxetidine hydrochloride, miconazole nitrate, chlorpromazine hydrochloride, amphotericin b, niclosamide or suggested (bepridil, ciclopirox, rescinnamine, flucytosine, vinblastine and carbidopa anti-schistosomal activities. This developed method is sensitive (200 schistosomula/well can be assayed, relevant to industrial (384-well microtiter plate compatibility and academic (96-well microtiter plate compatibility settings, translatable to functional genomics screens and drug assays, does not require a priori knowledge of schistosome biology and is quantitative.The wide-scale application of this fluorescence-based bioassay will greatly accelerate the objective identification of novel therapeutic lead targets/compounds to combat schistosomiasis. Adapting this bioassay for use with other parasitic worm species

  13. Carcinoembryonic antigen (CEA)

    International Nuclear Information System (INIS)

    Ephraim, K.H.; Cox, P.H.; Hamer, C.J.A. v.d.; Berends, W.; Delhez, H.

    1977-01-01

    The carcinoembryonic antigen (CEA) is a complex of antigen determinants and also the carrier of these determinants. Chemically it is a glycoprotein. Its occurrence in blood serum or urine is correlated with malignant disease. Several radioimmunoassays (RIA) have been developed, one by Hoffmann-Laroche and one by the Rotterdam Radiotherapeutic Institute. Both methods and the Hoffmann assay kit are tested. Specifications are given for isolation of the antigen, preparation of the antiserum, and the execution of the RIA. Biochemical and clinical aspects are discussed

  14. MRI Fusion-Targeted Transrectal Prostate Biopsy and the Role of Prostate-Specific Antigen Density and Prostate Health Index for the Detection of Clinically Significant Prostate Cancer in Southeast Asian Men.

    Science.gov (United States)

    Tan, Teck Wei; Png, Keng Siang; Lee, Chau Hung; Yuwono, Arianto; Yeow, Yuyi; Chong, Kian Tai; Lee, Yee Mun; Tan, Cher Heng; Tan, Yung Khan

    2017-11-01

    To test the hypothesis that targeted biopsy has a higher detection rate for clinically significant prostate cancer (csPCa) than systematic biopsy. We defined csPCa as any Gleason sum ≥7 cancer. In patients with Prostate Imaging Reporting and Data System (PI-RADS) 3 lesions, to determine if factors, such as prostate-specific antigen density (PSAD) and prostate health index (PHI), can predict csPCa and help select patients for biopsy. We report the first series of targeted biopsies in Southeast Asian men, with comparison against systematic biopsy. Consecutive patients were registered into a prospective institutional review board-approved database in our institution. We reviewed patients who underwent biopsy from May 2016 to June 2017. Inclusion criteria for our study were patients with at least one PI-RADS ≥3, and who underwent both targeted and systematic biopsies in the same sitting. There were 115 patients in the study, of whom 74 (64.3%) had a previous negative systematic biopsy. Targeted biopsies detected significantly less Gleason 6 cancers than systematic biopsies (p < 0.01), and demonstrated significantly higher sensitivity, specificity, positive predictive value, and negative predictive value (NPV) for the detection of csPCa. For patients with PI-RADS 3 lesions, PHI and PSAD were found to be the best predictors for csPCa. PSAD <0.10 ng/mL/mL had an NPV of 93% and sensitivity of 92%, while allowing 20% of patients to avoid biopsy. PHI cutoff of <27 would allow 34% of patients to avoid biopsy, with both sensitivity and NPV of 100%. Targeted prostate biopsies were found to be significantly superior to systematic biopsies for the detection of csPCa, while detecting less Gleason 6 cancer. Usage of PSAD and PHI cutoff levels in patients with PI-RADS 3 lesions may enable a number of patients to avoid unnecessary biopsy.

  15. Interpretation of sequential measurements of cancer antigen 125 (CA 125), carcinoembryonic antigen (CEA), and tissue polypeptide antigen (TPA) based on analytical imprecision and biological variation in the monitoring of ovarian cancer

    DEFF Research Database (Denmark)

    Tuxen, Malgorzata K.; Sölétormos, G; Petersen, P H

    2001-01-01

    The main objective with cancer antigen 125 (CA 125), carcinoembryonic antigen (CEA), and tissue polypeptide antigen (TPA) monitoring of ovarian cancer patients is to detect an early change of disease activity with high reliability. We hypothesized that a monitoring scheme for ovarian cancer patie...

  16. Comparison of Detection of Bovine Virus Diarrhea Virus Antigen in Various Types of Tissue and Fluid Samples Collected from Persistently Infected Cattle

    Science.gov (United States)

    Bovine viral diarrhea viruses are economically important pathogens of cattle. Most new infections are acquired from animals persistently infected with the virus. Surveillance programs rely on skin biopsies for detection of persistently infected cattle. The purpose of this study was to compare ant...

  17. A versatile SERS-based immunoassay for immunoglobulin detection using antigen-coated gold nanoparticles and malachite green-conjugated protein A/G

    Science.gov (United States)

    A surface enhanced Raman scattering (SERS) immunoassay for antibody detection in serum is described in the present work. The developed assay is conducted in solution and utilizes Au nanoparticles coated with the envelope (E) protein of West Nile Virus (WNV) as the SERS-active substrate and malachite...

  18. Antigen injection (image)

    Science.gov (United States)

    Leprosy is caused by the organism Mycobacterium leprae . The leprosy test involves injection of an antigen just under ... if your body has a current or recent leprosy infection. The injection site is labeled and examined ...

  19. Antigenic evaluation of a recombinant baculovirus-expressed Sarcocystis neurona SAG1 antigen.

    Science.gov (United States)

    Gupta, G D; Lakritz, J; Saville, W J; Livingston, R S; Dubey, J P; Middleton, J R; Marsh, A E

    2004-10-01

    Sarcocystis neurona is the primary parasite associated with equine protozoal myeloencephalitis (EPM). This is a commonly diagnosed neurological disorder in the Americas that infects the central nervous system of horses. Current serologic assays utilize culture-derived parasites as antigen. This method requires large numbers of parasites to be grown in culture, which is labor intensive and time consuming. Also, a culture-derived whole-parasite preparation contains conserved antigens that could cross-react with antibodies against other Sarcocystis species and members of Sarcocystidae such as Neospora spp., Hammondia spp., and Toxoplasma gondii. Therefore, there is a need to develop an improved method for the detection of S. neurona-specific antibodies. The sera of infected horses react strongly to surface antigen 1 (SnSAG1), an approximately 29-kDa protein, in immunoblot analysis, suggesting that it is an immunodominant antigen. The SnSAG1 gene of S. neurona was cloned, and recombinant S. neurona SAG1 protein (rSnSAG1-Bac) was expressed with the use of a baculovirus system. By immunoblot analysis, the rSnSAG1-Bac antigen detected antibodies to S. neurona from naturally infected and experimentally inoculated equids, cats, rabbit, mice, and skunk. This is the first report of a baculovirus-expressed recombinant S. neurona antigen being used to detect anti-S. neurona antibodies in a variety of host species.

  20. Monoclonal anti-human factor VII antibodies. Detection in plasma of a second protein antigenically and genetically related to factor VII.

    OpenAIRE

    Broze, G J; Hickman, S; Miletich, J P

    1985-01-01

    Several murine monoclonal anti-human Factor VII antibodies were produced using hybridoma technology. Two noncompetitive monoclonal antibodies were used to examine by Western blotting the Factor VII cross-reactive material (CRM) in normal human plasma and three commercially available congenitally Factor VII-deficient plasmas, and to construct a facile "sandwich" immunoassay for plasma Factor VII. A second, previously undescribed, form of Factor VII CRM was detected in human plasma, which on We...

  1. Should varicella-zoster virus culture be eliminated? A comparison of direct immunofluorescence antigen detection, culture, and PCR, with a historical review.

    Science.gov (United States)

    Wilson, D A; Yen-Lieberman, B; Schindler, S; Asamoto, K; Schold, J D; Procop, G W

    2012-12-01

    A comparison of direct fluorescent-antibody assay (DFA), culture, and two PCR assays disclosed sensitivities of 87.8%, 46.3%, and 97.6% and 100%, respectively. We reviewed 1,150 results for clinical specimens submitted for DFA and culture and found that only 17 were culture positive/DFA negative. The incremental cost to detect these 17 positives was $3,078/specimen.

  2. [The efficiency of the enzyme immunoassay test system opisthorchiasis-CIC-EIA-best to detect circulating immune complexes containing opisthorchis antigens in the serum of patients with opisthorchiasis].

    Science.gov (United States)

    Starkova, T V; Poletaeva, O G; Kovrova, E A; Krasovskaia, N N; Tkachenko, T N; Masiago, A V; Ofitserov, V I; Tereshchenko, A Iu

    2011-01-01

    The efficacy of a kit of Opisthorchiasis-CIC-EIA-Best reagents was evaluated using 270 sera from patients in the study and control groups. The kit showed a sufficient sensitivity (not less than 87.2%) and a high specificity (not less than 97.9%). The use of the above kit of the reagents for enzyme immunoassay in practical healthcare enables one to increase detection rates among the infested subjects on comprehensive examination of those with suspected opisthorchiasis.

  3. COMPARATIVE STUDY OF FILARIAL DETECTION BY MICROSCOPIC EXAMINATION AND SEROLOGICAL ASSAY UTILIZING BMR1 AND BMXSP RECOMBINANT ANTIGENS FOR EVALUATION OF FILARIASIS ELIMINATION PROGRAM AT KAMPUNG SAWAH AND PAMULANG, SOUTH TANGERANG DISTRICT, BANTEN, INDONESIA

    Directory of Open Access Journals (Sweden)

    Silvia F. Nasution

    2015-09-01

    Full Text Available South Tangerang district is one of the endemic areas for filariasis; and based on an evaluation study in 2008-2009 which covered several subdistricts, the prevalence of microfilaria was between 1–2.4%. Nevertheless, the evaluation by serological assay has never been reported. A cross-sectional study was conducted to detect the microfilaremia and anti-filarial IgG4 antibody status in Kp Sawah and Pamulang subdistricts. Cluster sampling was performed in Kp Sawah by collecting finger-prick blood (FPB and venous blood samples from inhabitants who lived with and nearby the four elephantiasis subjects in the area. The FPB were only collected in Pamulang area by consecutive sampling method. The detection method included microscopic evaluation of FPB and serological detection using recombinant antigens BmR1 and BmSXP by ELISA and lateral flow rapid tests. Symptomatic patients who had 2nd and 3rd degree of elephantiasis were clinically determined in 10% (4/40 subjects. Among those with elephantiasis, 2 were positive serologically but their microscopic results were all negative (40/40. Meanwhile, the microscopic result for 107 subjects from Pamulang were all negative. The results of the rapid tests showed that 15% (6/40 of the positive cases were detected by Brugia Rapid and 27.5% (11/40 by PanLF. Meanwhile, the ELISA showed that 20% (8/40 of the cases were positive with BmSXP, whereas only 2.5% or 1/40 sample was found to be positive with BmR1. Even though the sensitivity of the Rapid test was lower when compared to microscopic examination for these samples, the assay showed good specificity ranging from 72.5 to 97.5%. The optical density (OD values of ELISA has ranged between 0.3–3.045.

  4. Target-triggered signal turn-on detection of prostate specific antigen based on metal-enhanced fluorescence of Ag@SiO2@SiO2-RuBpy composite nanoparticles

    Science.gov (United States)

    Deng, Yun-Liang; Xu, Dang-Dang; Pang, Dai-Wen; Tang, Hong-Wu

    2017-02-01

    A three-layer core-shell nanostructure consisting of a silver core, a silica spacer, and a fluorescent dye RuBpy-doped outer silica layer was fabricated, and the optimal metal-enhanced fluorescence (MEF) distance was explored through adjusting the thickness of the silica spacer. The results show that the optimal distance is ˜10.4 nm with the maximum fluorescence enhancement factor 2.12. Then a new target-triggered MEF ‘turn-on’ strategy based on the optimized composite nanoparticles was successfully constructed for quantitative detection of prostate specific antigen (PSA), by using RuBpy as the energy donor and BHQ-2 as the acceptor. The hybridization of the complementary DNA of PSA-aptamer immobilized on the surface of the MEF nanoparticles with PSA-aptamer modified with BHQ-2, brought BHQ-2 in close proximity to RuBpy-doped silica shell and resulted in the decrease of fluorescence. In the presence of target PSA molecules, the BHQ-PSA aptamer is dissociated from the surface of the nanoparticles with the fluorescence switched on. Therefore, the assay of PSA was achieved by measuring the varying fluorescence intensity. The results show that PSA can be detected in the range of 1-100 ng ml-1 with a detection limit of 0.20 ng ml-1 (6.1 pM), which is 6.7-fold increase of that using hollow RuBpy-doped silica nanoparticles. Moreover, satisfactory results were obtained when PSA was detected in 1% serum.

  5. Characterization of the behavior of three definitions of prostate-specific antigen-based biochemical failure in relation to detection and follow-up biases: comparison with the American Society for Therapeutic Radiology and Oncology consensus definition.

    Science.gov (United States)

    Williams, Scott G

    2006-03-01

    To examine the impact of detection biases on three prostate cancer biochemical failure (bF) definitions in comparison with the existing American Society for Therapeutic Radiology and Oncology Consensus Definition (ACD). Three alternative bF definitions were tested against the ACD: three rises in prostate-specific antigen (PSA) level without backdating, nadir plus 2 ng/mL, and a threshold PSA level of >3 ng/mL, according to data from 1050 men. The mean time between PSA tests (MTBT), regularity of collection, and calendar year of analysis were examined in each bF definition. The MTBT produced a statistically significant difference in the derived hazard ratio for identification of bF in all definitions. The influence of test regularity was statistically significant beyond the median level of regularity in all definitions. The year of analysis impacted greatly on the ACD, whereas the three alternative definitions exhibited minor follow-up duration variations by comparison. The alternative definitions had reliable follow-up when the crude median time to censoring was at least 1.6 times greater than that of failure. Detection biases will always be a significant issue in defining bF. A number of alternative failure definitions have more predictable interactions with these biases than the existing ACD.

  6. Characterization of the behavior of three definitions of prostate-specific antigen-based biochemical failure in relation to detection and follow-up biases: Comparison with the American Society for Therapeutic Radiology and Oncology consensus definition

    International Nuclear Information System (INIS)

    Williams, Scott G.

    2006-01-01

    Purpose: To examine the impact of detection biases on three prostate cancer biochemical failure (bF) definitions in comparison with the existing American Society for Therapeutic Radiology and Oncology Consensus Definition (ACD). Methods and Materials: Three alternative bF definitions were tested against the ACD: three rises in prostate-specific antigen (PSA) level without backdating, nadir plus 2 ng/mL, and a threshold PSA level of >3 ng/mL, according to data from 1050 men. The mean time between PSA tests (MTBT), regularity of collection, and calendar year of analysis were examined in each bF definition. Results: The MTBT produced a statistically significant difference in the derived hazard ratio for identification of bF in all definitions. The influence of test regularity was statistically significant beyond the median level of regularity in all definitions. The year of analysis impacted greatly on the ACD, whereas the three alternative definitions exhibited minor follow-up duration variations by comparison. The alternative definitions had reliable follow-up when the crude median time to censoring was at least 1.6 times greater than that of failure. Conclusions: Detection biases will always be a significant issue in defining bF. A number of alternative failure definitions have more predictable interactions with these biases than the existing ACD

  7. Fate of challenge schistosomula in the murine anti-schistosome vaccine model

    International Nuclear Information System (INIS)

    Von Lichtenberg, F.; Correa-Oliveira, R.; Sher, A.

    1985-01-01

    Mice exposed to irradiated cercariae of Schistosoma mansoni develop a partial resistance to subsequent parasite challenge. In this study the authors utilized histopathologic methods to investigate the fate of both the immunizing and challenge cercariae in C57BL/6J mice. After immunization by percutaneous infection, a large number of the 50 Kr irradiated organisms could be detected in tissue sections of lung. However, as early as 2 weeks after immunization, the majority of these schistosomula apparently had died, leaving residual inflammatory foci. The numbers of these foci then gradually declined during the next 4 weeks of examination. Cercarial challenge of mice vaccinated 4 weeks previously provoked an intense eosinophil-enriched inflammatory response in percutaneously exposed ear pinnae. Despite these pronounced tissue reactions, no evidence of significant parasite damage or attrition was detected in this migration site. In contrast, schistosomula arriving in the lungs of vaccinated mice produced a greater number of residual inflammatory foci than did larvae appearing in the lungs of normal mice. In addition, challenge schistosomula were cleared from the lungs of vaccinated mice at a slower rate than they were from the lungs of control mice. These observations suggest that the lung is a major site of parasite attrition for both immunizing and challenge infections in the mouse irradiated vaccine model

  8. Next-generation detection of antigen-responsive T cells using DNA barcode-labeled peptide-major histocompatibility complex I multimers

    DEFF Research Database (Denmark)

    Bentzen, Amalie Kai; Marquard, Andrea Marion; Lyngaa, Rikke Birgitte

    2016-01-01

    sample using >1000 different peptide-MHC multimers labeled with individual DNA barcodes.After isolation of MHC multimer binding T cells their recognition are revealed by amplification andsequencing of the MHC multimer-associated DNA barcodes. The relative frequency of the sequencedDNA barcodes...... originating from a given peptide-MHC motif relates to the size of the antigenresponsiveT cell population. We have demonstrated the use of large panels of >1000 DNA barcodedMHC multimers for detection of rareT cell populations of virus and cancer-restricted origin in various tissues and compared...

  9. I-125 input into antibodies molecules specific to australian antigen

    International Nuclear Information System (INIS)

    Abdukayumov, A. M.; Chistyakov, P.G.; Garajshina, G. R.

    1999-01-01

    There are experimental data on I-125 input into antibodies molecules specific to superficial antigen of hepatitis B virus (australian antigen). Three ways of input are submitted: with the help of T chloramine usage, Bolton-Hunter Reagent and with the help of iodogen. There are also comparative characteristics of iodized products obtained: molar radioactivity, radiochemical frequency, immuno - reactivity. The report also discusses advantages and disadvantages of the used methods for inputting I-125 into antibodies to australian antigen in order to study the possibility of creating radio immunological test system for detecting superficial antigen of B hepatitis

  10. Enhanced detection sensitivity of prostate-specific antigen via PSA-conjugated gold nanoparticles based on localized surface plasmon resonance: GNP-coated anti-PSA/LSPR as a novel approach for the identification of prostate anomalies.

    Science.gov (United States)

    Jazayeri, M H; Amani, H; Pourfatollah, A A; Avan, A; Ferns, G A; Pazoki-Toroudi, H

    2016-10-01

    Prostate-specific antigen (PSA) is used to screen for prostate disease, although it has several limitations in its application as an organ-specific or cancer-specific marker. Furthermore, a highly specific/sensitive and/or label-free identification of PSA still remains a challenge in the diagnosis of prostate anomalies. We aimed to develop a gold nanoparticle (GNP)-conjugated anti-PSA antibody-based localized surface plasmon resonance (LSPR) as a novel approach to detect prostatic disease. A total of 25 nm colloidal gold particles were prepared followed by conjugation with anti-PSA pAb (GNPs-PSA pAb). LSPR was used to monitor the absorption changes of the aggregation of the particles. The size, shape and stability of the GNP-anti-PSA were evaluated by dynamic light scattering transmission electron microscopy (TEM) and zetasizer. The GNPs-conjugated PSA-pAb was successfully synthesized and subsequently characterized using ultraviolet absorption spectroscopy and TEM to determine the size distribution, crystallinity and stability of the particles (for example, stability of GNP: 443 mV). To increase the stability of the particles, we pegylated GNPs using an N-(3-dimethylaminopropyl)-N*-ethylcarbodiimide hydrochloride (EDC)/N-hydroxylsuccinimide (NHS) linker (for example, stability of GNP after pegylation: 272 mV). We found a significant increase in the absorbance and intensity of the particles with extinction peak at 545/2 nm, which was shifted by ~1 nm after conjugation. To illustrate the potential of the GNPs-PSA pAb to bind specifically to PSA, LSPR was used. We found that the extinction peak shifted 3 nm for a solution of 100 nM unlabeled antigen. In summary, we have established a novel approach for improving the efficacy/sensitivity of PSA in the assessment of prostate disease, supporting further investigation on the diagnostic value of GNP-conjugated anti-PSA/LSPR for the detection of prostate cancer.

  11. Detection of antibodies to hepatitis B core antigen using the Abbott ARCHITECT anti-HBc assay: analysis of borderline reactive sera.

    Science.gov (United States)

    Ollier, Laurence; Laffont, Catherine; Kechkekian, Aurore; Doglio, Alain; Giordanengo, Valérie

    2008-12-01

    Routine use of the automated chemiluminescent microparticle immunoassay Abbott ARCHITECT anti-HBc for diagnosis of hepatitis B is limited in case of borderline reactive sera with low signal close to the cut-off index. In order to determine the significance of anti-HBc detection when borderline reactivity occurs using the ARCHITECT anti-HBc assay, a comparative study was designed. 3540 serum samples collected over a 2-month period in the hospital of Nice were examined for markers of HBV infection (HBsAg, anti-HBs and anti-HBc). One hundred seven samples with sufficient volume and with borderline reactivity by the ARCHITECT assay were tested by two other anti-HBc assays, a microparticle enzyme immunoassay (MEIA, AxSYM Core, Abbott Laboratories, IL, USA) and an enzyme linked fluorescent assay (ELFA, VIDAS Anti-HBc Total II, bioMérieux, Lyon, France). Only 46 samples were confirmed by the AxSYM and the VIDAS assays. Additional serological information linked to patient history showed that the remaining samples (61) were false positives (11), had low titer of anti-HBc antibodies (13), or were inconclusive (37). This comparative study highlighted the existence of a grey zone around the cut-off index. Confirmative results through a different immunoassay are needed to confirm the diagnosis of HBV on borderline reactive sera using the ARCHITECT anti-HBc assay.

  12. Autoradiographic detection of [125I]-secondary antiserum: a sensitive light and electron microscopic labeling method compatible with peroxidase immunocytochemistry for dual localization of neuronal antigens

    International Nuclear Information System (INIS)

    Pickel, V.M.; Chan, J.; Milner, T.A.

    1986-01-01

    We examined whether autoradiographic localization of [ 125 I]-antirabbit immunoglobulin (IgG) was suitable for light and electron microscopic detection of a rabbit antiserum to the catecholamine-synthesizing enzyme, tyrosine hydroxylase (TH), and whether autoradiographic and peroxidase labeling could be combined for simultaneous immunocytochemical identification of TH and neuropeptides in brain. Adult rat brains were fixed by aortic arch perfusion with acrolein and paraformaldehyde. Vibratome sections of the fixed tissues were incubated with various dilutions of TH antiserum followed by [ 125 I]-secondary IgG. These sections were then directly processed for autoradiography or were incubated with rabbit antiserum to substance P (SP) or methionine [Met5]-enkephalin (ME). These latter sections were then processed by the peroxidase-antiperoxidase (PAP) or conjugated peroxidase methods followed by autoradiography. Exposure periods of 12-20 days for light microscopy or 90 days for electron microscopy yielded substantial accumulations of silver grains even at the highest (1:30,000) dilution of TH antiserum. At this dilution, immunoreactivity for TH was virtually nondetectable by PAP and conjugated peroxidase methods. The differential sensitivities of the autoradiographic versus peroxidase methods provided a means for separable identification of rabbit antiserum to TH and to SP or ME. Ultrastructural analysis of the catecholaminergic neurons in the medial nuclei of the solitary tract (NTS) showed selective cytoplasmic localization of silver grains for [ 125 I]-labeling of TH in perikarya, dendrites, and terminals. Within single thin sections prepared for dual labeling, the peroxidase marker for SP and for ME was differentially localized with respect to autoradiographic labeling of TH

  13. Test characteristics of two rapid antigen detection tests (SD FK50 and SD FK60 for the diagnosis of malaria in returned travellers

    Directory of Open Access Journals (Sweden)

    Van Esbroeck Marjan

    2009-05-01

    Full Text Available Abstract Background Two malaria rapid diagnostic tests were evaluated in a travel clinic setting: the SD FK50 Malaria Ag Plasmodium falciparum test (a two-band test and the SD FK60 Malaria Ag P. falciparum/Pan test (a three-band test. Methods A panel of stored whole blood samples (n = 452 and n = 614 for FK50 and FK60, respectively from returned travellers was used. The reference method was microscopy with PCR in case of discordant results. Results For both tests, overall sensitivity for the detection of P. falciparum was 93.5%, reaching 97.6% and 100% at parasite densities above 100 and 1,000/μl respectively. Overall sensitivities for Plasmodium vivax, Plasmo