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Sample records for cysticercosis antigens antibodies

  1. Multiantigen Print Immunoassay for Comparison of Diagnostic Antigens for Taenia solium Cysticercosis and Taeniasis▿

    Science.gov (United States)

    Handali, Sukwan; Klarman, Molly; Gaspard, Amanda N.; Noh, John; Lee, Yeuk-Mui; Rodriguez, Silvia; Gonzalez, Armando E.; Garcia, Hector H.; Gilman, Robert H.; Tsang, Victor C. W.; Wilkins, Patricia P.

    2010-01-01

    One of the best-characterized tests for the diagnosis of neurocysticercosis is the enzyme-linked immunoelectrotransfer blot assay, developed at the CDC, which uses lentil lectin-purified glycoproteins (LLGPs) extracted from Taenia solium cysticerci. The purification of the LLGP antigens has been difficult to standardize, and the polyacrylamide gel system used for the immunoblot assay is not easily transferable to other laboratories. In this study, we developed a multiantigen printing immunoassay (MAPIA) to compare the performance of multiple recombinant Taenia solium proteins with the potential for the detection of cysticercosis and taeniasis. We prepared MAPIA strips using six cysticercosis and two taeniasis diagnostic proteins and compared the performance of the proteins with sera collected from defined cysticercosis and taeniasis cases. Of the six cysticercosis antigens, rT24H performed well in detecting cases with two or more viable cysts in the brain (sensitivity and specificity, 97% and 99.4%, respectively); the use of a combination of cysticercosis antigens did not improve the sensitivity of the test and decreased the specificity. None of the antigens could differentiate the different clinical presentations of cysticercosis. Both of the taeniasis antigens (rES33 and rES38) had the same sensitivity of 99.4% and specificities of 93.9% and 94.5%, respectively. Some cross-reactivity against rES33 and rES38 was found, especially with sera from cases infected with Schistosoma mansoni. We conclude that MAPIA is a simple and effective tool that may be used to compare antibody responses to different cysticercosis and taeniasis antigens and, in this case, may be useful for the rapid detection of T. solium cases. PMID:19906893

  2. Multiantigen print immunoassay for comparison of diagnostic antigens for Taenia solium cysticercosis and taeniasis.

    Science.gov (United States)

    Handali, Sukwan; Klarman, Molly; Gaspard, Amanda N; Noh, John; Lee, Yeuk-Mui; Rodriguez, Silvia; Gonzalez, Armando E; Garcia, Hector H; Gilman, Robert H; Tsang, Victor C W; Wilkins, Patricia P

    2010-01-01

    One of the best-characterized tests for the diagnosis of neurocysticercosis is the enzyme-linked immunoelectrotransfer blot assay, developed at the CDC, which uses lentil lectin-purified glycoproteins (LLGPs) extracted from Taenia solium cysticerci. The purification of the LLGP antigens has been difficult to standardize, and the polyacrylamide gel system used for the immunoblot assay is not easily transferable to other laboratories. In this study, we developed a multiantigen printing immunoassay (MAPIA) to compare the performance of multiple recombinant Taenia solium proteins with the potential for the detection of cysticercosis and taeniasis. We prepared MAPIA strips using six cysticercosis and two taeniasis diagnostic proteins and compared the performance of the proteins with sera collected from defined cysticercosis and taeniasis cases. Of the six cysticercosis antigens, rT24H performed well in detecting cases with two or more viable cysts in the brain (sensitivity and specificity, 97% and 99.4%, respectively); the use of a combination of cysticercosis antigens did not improve the sensitivity of the test and decreased the specificity. None of the antigens could differentiate the different clinical presentations of cysticercosis. Both of the taeniasis antigens (rES33 and rES38) had the same sensitivity of 99.4% and specificities of 93.9% and 94.5%, respectively. Some cross-reactivity against rES33 and rES38 was found, especially with sera from cases infected with Schistosoma mansoni. We conclude that MAPIA is a simple and effective tool that may be used to compare antibody responses to different cysticercosis and taeniasis antigens and, in this case, may be useful for the rapid detection of T. solium cases.

  3. Immunological variation in Taenia solium porcine cysticercosis: measurement on the variation of the antibody immune response of naturally infected pigs against antigens extracted from their own cysticerci and from those of different pigs.

    Science.gov (United States)

    Ostoa-Saloma, Pedro; Esquivel-Velázquez, Marcela; Larralde, Carlos

    2013-10-18

    Although it is widely assumed that both antigen and host immunological variability are involved in the variable intensity of natural porcine infections by Taenia solium (T. solium) cysticercis and success of immunodiagnostic tests vaccines, the magnitude of such combined variability has not been studied or measured at all. In this paper we report statistical data on the variability of the antibody response of naturally infected pigs against the antigens extracted from the vesicular fluids of their own infecting cysts (variance within pigs) and against antigen samples extracted from cysts of other cysticercotic pigs (variance among pigs). The variation between pigs was greater than the inter-pigs variations, which suggests that a concomitant immunity process prevents the establishment of cysts coming from a subsequent challenge. In so doing, we found that there is not a single antigenic band that was recognized by all hosts and that antigens varied among the cysts within the same pigs as well as among pigs. Our results may be valuable for the improvement of immunodiagnostic tests and of effective vaccines against naturally acquired porcine T. solium cysticercosis. Copyright © 2013 Elsevier B.V. All rights reserved.

  4. Cysticercosis

    International Nuclear Information System (INIS)

    Moosa, A.; Dawood, A.A.

    1983-01-01

    Cysticercosis is the most common parasitic disease in the world affecting the central nervous system. The article discusses the pathogenesis of cysticercosis as well as the pathological types of cysticercosis such as subcutaneous nodules, lingual nodules and orbital nodules. Cerebral cysticercosis is discussed in greater depth together with its clinical features. Attention is also given to the diagnosis of cerebral cysticercosis and diagnostic aids such as computerized tomography that can be used

  5. Cysticercosis

    Energy Technology Data Exchange (ETDEWEB)

    Moosa, A.; Dawood, A.A. (Natal Univ., Durban (South Africa). Dept. of Pediatrics and Child Health)

    1983-12-01

    Cysticercosis is the most common parasitic disease in the world affecting the central nervous system. The article discusses the pathogenesis of cysticercosis as well as the pathological types of cysticercosis such as subcutaneous nodules, lingual nodules and orbital nodules. Cerebral cysticercosis is discussed in greater depth together with its clinical features. Attention is also given to the diagnosis of cerebral cysticercosis and diagnostic aids such as computerized tomography that can be used.

  6. [Western Blot diagnostic yield for simultaneous antibody-detection in patients with human cysticercosis, hydatidosis, and human fascioliasis].

    Science.gov (United States)

    Davelois, Kelly; Escalante, Hermes; Jara, César

    2016-01-01

    . To determine the diagnostic yield using western blotting to simultaneously detect antibodies in patients with human cysticercosis, hydatidosis, and human fascioliasis. Materials and methods . Cross-sectional study of diagnostic yield assessment. Excretory/secretory antigens were obtained from Taenia solium larvae, Echinococcus granulosus cysts, and the adult flukes of Fasciola hepática, which were then separated using the polyacrylamide gel electrophoresis technique, transferred, and attached to a nitrocellulose membrane to be probed with sera from the patient infected with the three parasites. The sensitivity of the technique was assessed using 300 individual serum samples, 60 pools of two parasites, and 20 pools of three parasites with 75 sera from patients with other parasites, 10 from patients with other diseases, and 15 from patients without parasites. Results . The technique revealed 13 glycoproteins (GP): GP 35, 31, 24, 23, 18, 17, 14, and 13 kDa for cysticercosis; GP 8, 16, and 21 kDa for hydatidosis; and GP 17 and 23 kDa for fascioliasis. The test detected the presence of antibodies with a sensitivity of 96% (95% confidence interval [CI] = 94.62-98.54%) in the detection of one or the thirteen bands, a specificity of 100% (95% CI = 99.50-100.00%); individually, there was a sensitivity for cysticercosis of 97% (95% CI = 93.16-100.00%), for hydatidosis of 94% (95% CI = 88.85-99.15%) and for fascioliasis of 96% (95% CI = 91.66-100.00%). Conclusions . Western blotting is effective in the simultaneous detection of antibodies in patients with human cysticercosis, hydatidosis, and fascioliasis, and it can be used as a diagnostic test to either rule out or confirm the presence of antibodies in endemic areas.

  7. Antigen antibody interactions

    CERN Document Server

    DeLisi, Charles

    1976-01-01

    1. 1 Organization of the Immune System One of the most important survival mechanisms of vertebrates is their ability to recognize and respond to the onslaught of pathogenic microbes to which they are conti- ously exposed. The collection of host cells and molecules involved in this recognition­ 12 response function constitutes its immune system. In man, it comprises about 10 cells 20 (lymphocytes) and 10 molecules (immunoglobulins). Its ontogenic development is c- strained by the requirement that it be capable of responding to an almost limitless variety of molecular configurations on foreign substances, while simultaneously remaining inert to those on self components. It has thus evolved to discriminate, with exquisite precision, between molecular patterns. The foreign substances which induce a response, called antigens, are typically large molecules such as proteins and polysaccharides. The portions of these with which immunoglobulins interact are called epitopes or determinants. A typical protein epitope m...

  8. Antigen recognition by IgG4 antibodies in human trichinellosis

    Directory of Open Access Journals (Sweden)

    Pinelli E.

    2001-06-01

    Full Text Available The antibody isotype response to Trichinella spiralis excretory/secretory (ES products of muscle larva was examined using sera from patients with confirmed trichinellosis. Using Western blots we identify components of the ES antigen that are recognized by IgM and IgG antibodies. A 45 kDa component was strongly recognized by different antibody classes and subclasses. We observed a 45 kDa-specific lgG4 response that was detected exclusively using sera of patients with trichinellosis and not of patients with echinococcosis, filariasis, cysticercosis, ascariasis, strongyloidiasis or toxocariasis. These results are relevant for the diagnosis of human trichinellosis.

  9. Serodiagnosis of Human Cysticercosis by Using Antigens from Vesicular Fluid of Taenia crassiceps Cysticerci

    Science.gov (United States)

    Bueno, Ednéia C.; Snege, Miriam; Vaz, Adelaide J.; Leser, Paulo G.

    2001-01-01

    Neurocysticercosis (NC), caused by the presence of Taenia solium metacestodes in tissues, is a severe parasitic infection of the central nervous system with universal distribution. To determine the efficiency of enzyme-linked immunosorbent assay (ELISA) and immunoblot with antigens of T. crassiceps vesicular fluid (Tcra) compared to standard techniques (indirect immunofluorescence test [IFT] and complement fixation test [CFT]) using T. solium cysticerci (Tso) for the serodiagnosis of NC, we studied serum samples from 24 patients with NC, 30 supposedly healthy individuals, 76 blood bank donors, 45 individuals with other non-NC parasitoses, and 97 samples from individuals screened for cysticercosis serology (SC). The sensitivity observed was 100% for ELISA-Tso and ELISA-Tcra, 91.7% for the IFT, and 87.5% for the CFT. The specificity was 90% for ELISA-Tso, 96.7% for ELISA-Tcra, 50% for IFT, and 63.3% for CFT. The efficiency was highest for ELISA-Tcra, followed by ELISA-Tso, IFT, and CFT. Of the 23 samples from SC group, which were reactive to ELISA-Tso and/or ELISA-Tcra, only 3 were positive to immunblot-Tcra (specific peptides of 14- and 18-kDa) and to glycoprotein peptides purified from Tcra antigen (gp-Tcra), showing the low predictive value of ELISA for screening. None of the samples from the remaining groups showed specific reactivity in immunoblot-Tcra. These results demonstrate that ELISA-Tcra can be used as a screening method for the serodiagnosis of NC and support the need for specific tests for confirmation of the results. The immunoblot can be used as a confirmatory test both with Tcra and gp-Tcra, with the latter having an advantage in terms of visualization of the results. PMID:11687454

  10. Human cysticercosis and Indian scenario: a review

    Indian Academy of Sciences (India)

    PRAKASH KUMAR

    Porcine cysticercosis is a successful experimental model for T. solium cysticercosis, ..... cysticercus antibodies in slum, rural and urban populations in and around .... World Health Organization 1983 Guidelines for Surveillance. Prevention and ...

  11. Serological diagnosis of Taenia solium in pigs: No measurable circulating antigens and antibody response following exposure to Taenia saginata oncospheres.

    Science.gov (United States)

    Dorny, P; Dermauw, V; Van Hul, A; Trevisan, C; Gabriël, S

    2017-10-15

    Taenia solium taeniasis/cysticercosis is a zoonosis included in the WHO's list of neglected tropical diseases. Accurate diagnostic tools for humans and pigs are needed to monitor intervention outcomes. Currently used diagnostic tools for porcine cysticercosis all have drawbacks. Serological tests are mainly confronted with problems of specificity. More specifically, circulating antigen detecting tests cross-react with Taenia hydatigena and the possibility of transient antigens as a result of aborted infections is suspected. Furthermore, the hypothesis has been raised that hatched ingested eggs of other Taenia species may lead to a transient antibody response or to the presence of circulating antigen detectable by serological tests used for porcine cysticercosis. Here we describe the results of a study that consisted of oral administration of Taenia saginata eggs to five piglets followed by serological testing during five weeks and necropsy aiming at studying possible cross reactions in serological tests used for porcine cysticercosis. The infectivity of the eggs was verified by in vitro hatching and by experimental infection of a calf. One piglet developed acute respiratory disease and died on day 6 post infection. The remaining four piglets did not show any clinical signs until euthanasia. None of the serum samples from four piglets collected between days 0 and 35 post infection gave a positive reaction in the B158/B60 Ag-ELISA and in a commercial Western blot for antibody detection. In conclusion, this study showed that experimental exposure of four pigs to T. saginata eggs did not result in positive serologies for T. solium. These results may help interpreting serological results in monitoring of T. solium control programmes. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. [Limbic encephalitis with antibodies against intracellular antigens].

    Science.gov (United States)

    Morita, Akihiko; Kamei, Satoshi

    2010-04-01

    Limbic encephalitis is a paraneoplastic syndrome that is often associated with small cell lung cancer (SCLC), breast cancer, testicular tumors, teratoma, Hodgkin's lymphoma and thymoma. The common clinical manifestations of limbic encephalitis are subacute onset, cognitive dysfunction, seizures and psychiatric symptoms. Paraneoplastic neurological disorders are considered to occur because of cytotoxic T cell responses and antibodies against target neuronal proteins that are usually expressed by an underlying tumor. The main intracellular antigens related to limbic encephalitis are Hu, Ma2, and less frequently CV2/CRMP5 and amphiphysin. The anti-Hu antibody, which is involved in cerebellar degeneration and extensive or multifocal encephalomyelitis such as limbic encephalitis is closely associated with a history of smoking and SCLC. The anti-Ma2 antibody is associated with encephalitis of the limbic system, hypothalamus and brain-stem. For this reason, some patients with limbic encephalitis have sleep disorders (including REM sleep abnormalities), severe hypokinesis and gaze palsy in addition to limbic dysfunction. In men aged less than 50 years, anti-Ma2 antibody encephalitis is almost always associated with testicular germ-cell tumors that are occasionally difficult to detect. In older men and women, the most common tumors are non-SCLC and breast cancer. Limbic encephalitis associated with cell-surface antigens (e.g., voltage-gated potassium channels, NMDA receptors) is mediated by antibodies and often improves after a reduction in the antibody titer and after tumor resection. Patients with antibodies against intracellular antigens, except for those with anti-Ma2 antibodies and testicular tumors, are less responsive. Early diagnosis and treatment with immunotherapy, tumor resection or both are important for improving or stabilizing the condition of limbic encephalitis.

  13. Neuronal surface antigen antibodies in limbic encephalitis

    Science.gov (United States)

    Graus, F; Saiz, A; Lai, M; Bruna, J; López, F; Sabater, L; Blanco, Y; Rey, M J.; Ribalta, T; Dalmau, J

    2008-01-01

    Objective: To report the frequency and type of antibodies against neuronal surface antigens (NSA-ab) in limbic encephalitis (LE). Methods: Analysis of clinical features, neuropathologic findings, and detection of NSA-ab using immunochemistry on rat tissue and neuronal cultures in a series of 45 patients with paraneoplastic (23) or idiopathic (22) LE. Results: NSA-ab were identified in 29 patients (64%; 12 paraneoplastic, 17 idiopathic). Thirteen patients had voltage-gated potassium channels (VGKC)-ab, 11 novel NSA (nNSA)-ab, and 5 NMDA receptor (NMDAR)-ab. nNSA-ab did not identify a common antigen and were more frequent in paraneoplastic than idiopathic LE (39% vs 9%; p = 0.03). When compared with VGKC-ab or NMDAR-ab, the nNSA associated more frequently with intraneuronal antibodies (11% vs 73%; p = 0.001). Of 12 patients (9 nNSA-ab, 2 VGKC-ab, 1 NMDAR-ab) with paraneoplastic LE and NSA-ab, concomitant intraneuronal antibodies occurred in 9 (75%). None of these 12 patients improved with immunotherapy. The autopsy of three of them showed neuronal loss, microgliosis, and cytotoxic T cell infiltrates in the hippocampus and amygdala. These findings were compatible with a T-cell mediated neuronal damage. In contrast, 13 of 17 (76%) patients with idiopathic LE and NSA-ab (8 VGKC-ab, 4 NMDAR-ab, 1 nNSA-ab) and 1 of 5 (20%) without antibodies had clinical improvement (p = 0.04). Conclusions: In paraneoplastic limbic encephalitis (LE), novel antibodies against neuronal surface antigens (nNSA-ab) occur frequently, coexist with antibodies against intracellular antigens, and these cases are refractory to immunotherapy. In idiopathic LE, the likelihood of improvement is significantly higher in patients with NSA-ab than in those without antibodies. GLOSSARY GAD = glutamic acid decarboxylase; LE = limbic encephalitis; NMDAR = N-methyl-D-aspartate receptor; NSA = neuronal surface antigens; nNSA = novel NSA; SCLC = small-cell lung cancer; VGKC = voltage-gated potassium channels

  14. Taenia solium Human Cysticercosis: A Systematic Review of Sero-epidemiological Data from Endemic Zones around the World

    OpenAIRE

    Coral-Almeida, Marco; Gabri?l, Sarah; Abatih, Emmanuel Nji; Praet, Nicolas; Benitez, Washington; Dorny, Pierre

    2015-01-01

    Background: Taenia solium cysticercosis is a zoonotic neglected disease responsible for severe health disorders such as seizures and death. Understanding the epidemiology of human cysticercosis (HCC) in endemic regions will help to expose critical information about the transmission of the disease, which could be used to design efficient control programs. This review gathered serological data on apparent prevalence of T. solium circulating antigens and/or seroprevalence of T. solium antibodies...

  15. Characterisation of antibody responses in pigs induced by recombinant oncosphere antigens from Taenia solium.

    Science.gov (United States)

    Jayashi, César M; Gonzalez, Armando E; Castillo Neyra, Ricardo; Kyngdon, Craig T; Gauci, Charles G; Lightowlers, Marshall W

    2012-12-14

    Recombinant antigens cloned from the oncosphere life cycle stage of the cestode parasite Taenia solium (T. solium) have been proven to be effective as vaccines for protecting pigs against infections with T. solium. Previous studies have defined three different host protective oncosphere antigens, TSOL18, TSOL16 and TSOL45. In this study, we evaluated the potential for combining the antigens TSOL16 and TSOL18 as a practical vaccine. Firstly, in a laboratory trial, we compared the immunogenicity of the combined antigens (TSOL16/18) versus the immunogenicity of the antigens separately. Secondly, in a field trial, we tested the ability of the TSOL16/18 vaccine to induce detectable antibody responses in animals living under environmental stress and traditionally reared in areas where T. solium cysticercosis is endemic; and finally, we characterised the immune response of the study population. Pigs of 8-16 weeks of age were vaccinated with 200 μg each of TSOL16 and TSOL18, plus 5mg of Quil-A. Specific total IgG, IgG(1) and IgG(2) antibody responses induced by TSOL16 and TSOL18 were determined with ELISA. The immunogenicity of both antigens was retained in the combined TSOL16/18 vaccine. The combined vaccine TSOL16/18 induced detectable specific anti-TSOL18 antibody responses in 100% (113/113) and specific anti-TSOL16 in 99% (112/113) of the vaccinated animals measured at 2 weeks following the booster vaccination. From the two IgG antibody subtypes analysed we found there was stronger response to IgG(2). Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Monoclonal antibodies to carcino-embryonic antigen

    International Nuclear Information System (INIS)

    Teh, Jinghee; McKenzie, I.F.C.

    1990-01-01

    With the aim of producing new MoAb to colorectal carcinoma, immunization with cell suspensions of a fresh colonic tumour was performed and MoAb 17C4 was obtained. To produce other MoAb to colon cancer, an immunization protocol using fresh tumour, colonic cell lines and sera from patients with colonic tumours was employed and resulted in MoAb JGT-13, LK-4 and XPX-13. MoAb I-1 and O-1 were raised against sera from patients with colon cancer to produce MoAb directed against circulating tumour associated antigens. The six antibodies gave a range of reactions with normal and malignant tissues, indicating that they most likely reacted with different epitopes. Thus, apart from the reactions of 17C4, LK-4 and XPX-13 with fresh and formalin-fixed granulocytes, none of the antibodies reacted with formalin-fixed normal tissues. Despite the apparent specificity of these MoAb for colon cancer, serum testing using MoAb gave similar results to carcino-embryonic antigen polyclonal antibodies, that is the MoAb gave no obvious advantage. 9 refs., 1 tab., 3 figs

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

    Directory of Open Access Journals (Sweden)

    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.

  18. An indirect antibody assay using haptenated antigen and 125I-labelled anti-hapten antibody

    International Nuclear Information System (INIS)

    Aalberse, R.C.; Amsterdam Univ.

    1978-01-01

    Hapten (trinitrophenyl) was coupled to antigen (ovalbumin). The haptenated antigen was bound by anti-ovalbumin antibody and binding was quantitated with 125 I-labelled anti-hapten antibodies. Thus, with a single radioactive reagent, antibodies against a variety of antigens can be detected while the problems inherent in a labelled antiglobulin binding test are avoided. In the ovalbumin system, the haptenated antigen binding test proved to be approximately 20 times as sensitive as the iodinated ovalbumin binding test

  19. Antigen-targeting strategies using single-domain antibody fragments

    NARCIS (Netherlands)

    Duarte, Joao Nuno Silva

    2017-01-01

    Antibodies display high selectivity and affinity and have been the preferred platform for antigen targeting. Despite the development of antigen-delivery systems that enable T cell activation, targeting approaches that enhance antibody responses need improvement. This need specially applies to poorly

  20. Development and evaluation of porcine cysticercosis QuickELISA in Triturus EIA analyzer.

    Science.gov (United States)

    Handali, Sukwan; Pattabhi, Sowmya; Lee, Yeuk-Mui; Silva-Ibanez, Maria; Kovalenko, Victor A; Levin, Andrew E; Gonzalez, Armando E; Roberts, Jacquelin M; Garcia, Hector H; Gilman, Robert H; Hancock, Kathy; Tsang, Victor C W

    2010-01-01

    We evaluated three diagnostic antigens (recombinant GP50, recombinant T24H, and synthetic Ts18var1) for cysticercosis and found that all three performed well in detecting cysticercosis in humans and pigs in several assay formats. These antigens were adapted to a new antibody detection format (QuickELISA). With one single incubation step which involves all reactants except the enzyme substrate, the QuickELISA is particularly suited for automation. We formatted the QuickELISA for the Triturus EIA analyzer for testing large numbers of samples. We found that in QuickELISA formats rGP50 and rT24H have better sensitivity and specificity than sTs18var1 for detecting porcine cysticercosis.

  1. Microradioimmunoassay for antibodies to tumor-associated antigens

    International Nuclear Information System (INIS)

    Huang, J.C.C.; Berczi, I.; Froese, G.; Tsay, H.M.; Sehon, A.H.

    1975-01-01

    A versatile microradioimmunoassay for the detection of antibodies to tumor-associated and other tissue antigens was described. The method involved: the preparation of solid-phase antigen with cultured (already adhered) or noncultured cells (sedimented by centrifugation) fixed to Micro-Test plates with neutral buffered formaldehyde or absolute methanol; the incubation of the antigen with test or control sera; and the incubation of the antigen with radioiodinated antiglobulin antibody. The nonspecific background of radioactivity was reduced to an acceptable level by the fixed cells being precoated in the wells with 0.5 percent bovine serum albumin in phosphate-buffered saline which was also used for the dilution of sera and labeled antiglobulin antibody. Tumor cells in primary cultures gave a high background, as compared to long-term cultures, which was due to the presence of immunoglobulins (most likely tumor-specific antibody). The specific antibody response to a syngeneic mouse tumor was demonstrated by this technique. (auth)

  2. Molecular aspects of antibody-antigen interactions : size reduction of a herpes simplex virus neutralizing antibody and its antigen

    NARCIS (Netherlands)

    Schellekens, Gerardus Antonius

    1996-01-01

    Antibody molecules, produced as a response against foreign substances, interact with their antigen in a very specific manner. Antibodies with a predetermined specificity (monoclonal antibodies) can be produced and are widely used in medicine and science as indicator molecules. Genetic engineering of

  3. 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

  4. Monoclonal antibodies to Nocardia asteroides and Nocardia brasiliensis antigens.

    OpenAIRE

    Jiménez, T; Díaz, A M; Zlotnik, H

    1990-01-01

    Nocardia asteroides and Nocardia brasiliensis whole-cell extracts were used as antigens to generate monoclonal antibodies (MAbs). Six stable hybrid cell lines secreting anti-Nocardia spp. MAbs were obtained. These were characterized by enzyme-linked immunosorbent assay, Western blot (immunoblot), and immunofluorescence assay. Although all the MAbs exhibited different degrees of cross-reactivity with N. asteroides and N. brasiliensis antigens as well as with culture-filtrate antigens from Myco...

  5. Generation of monoclonal antibodies against highly conserved antigens.

    Directory of Open Access Journals (Sweden)

    Hongzhe Zhou

    Full Text Available BACKGROUND: Therapeutic antibody development is one of the fastest growing areas of the pharmaceutical industry. Generating high-quality monoclonal antibodies against a given therapeutic target is very crucial for the success of the drug development. However, due to immune tolerance, some proteins that are highly conserved between mice and humans are not very immunogenic in mice, making it difficult to generate antibodies using a conventional approach. METHODOLOGY/PRINCIPAL FINDINGS: In this report, the impaired immune tolerance of NZB/W mice was exploited to generate monoclonal antibodies against highly conserved or self-antigens. Using two highly conserved human antigens (MIF and HMGB1 and one mouse self-antigen (TNF-alpha as examples, we demonstrate here that multiple clones of high affinity, highly specific antibodies with desired biological activities can be generated, using the NZB/W mouse as the immunization host and a T cell-specific tag fused to a recombinant antigen to stimulate the immune system. CONCLUSIONS/SIGNIFICANCE: We developed an efficient and universal method for generating surrogate or therapeutic antibodies against "difficult antigens" to facilitate the development of therapeutic antibodies.

  6. High throughput production of mouse monoclonal antibodies using antigen microarrays

    DEFF Research Database (Denmark)

    De Masi, Federico; Chiarella, P.; Wilhelm, H.

    2005-01-01

    Recent advances in proteomics research underscore the increasing need for high-affinity monoclonal antibodies, which are still generated with lengthy, low-throughput antibody production techniques. Here we present a semi-automated, high-throughput method of hybridoma generation and identification....... Monoclonal antibodies were raised to different targets in single batch runs of 6-10 wk using multiplexed immunisations, automated fusion and cell-culture, and a novel antigen-coated microarray-screening assay. In a large-scale experiment, where eight mice were immunized with ten antigens each, we generated...

  7. Lingual cysticercosis

    Directory of Open Access Journals (Sweden)

    A P Pichare

    2014-01-01

    Full Text Available Cysticercosis is a disease caused by larval form of tapeworm. Cysticercus cellulose primarily develops in tissues of pigs. Infection of human tissues is unusual and affliction of the oral cavity is rare. We, herein, present a case of lingual cysticercosis without involvement of any other site. A 5-year-old male, non-vegetarian child presented with a painless, pearly white, solitary nodular swelling on posterior dorsal side of tongue since 3 months. Excision biopsy was done. Histopathology revealed cysticercous cellulose in tongue muscles.

  8. A radioimmunoassay for human antibody specific for microbial antigens

    International Nuclear Information System (INIS)

    Tew, J.G.; Burmeister, J.; Greene, E.J.; Pflaumer, S.K.; Goldstein, J.

    1977-01-01

    A simple and sensitive method for detecting and quantitating antibody specific or microbial antigens is described. Bacterial, fungal, parasitic or viral antigens attached to bromoacetyl cellulose or the intact cells themselves were added to a series of two-fold dilutions of human serum. After a short incubation period, which allowed human antibody to attach to the antigens, the complex was thoroughly washed and carbon-14 labeled anti-human light chain antibody was added to each dilution. The resulting complex was washed, collected on a filter pad, placed in a scintillation vial and radioassayed. The relationship between radioactivity bound and -log 2 of the serum dilution was linear. The endpoint for each assay and a confidence interval was calculated by doing inverse prediction from simple linear regression. Results obtained using this assay indicated the presence of antibody in a pool of normal human sera specific for herpes virus and for both cell surface and intracellular antigens of Streptococcus mutans, Naegleria fowleri and Cryptococcus neoformans. In general the dominant response was against the intracellular antigens rather than cell surface antigens

  9. 21 CFR 660.1 - Antibody to Hepatitis B Surface Antigen.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Antibody to Hepatitis B Surface Antigen. 660.1... Hepatitis B Surface Antigen § 660.1 Antibody to Hepatitis B Surface Antigen. (a) Proper name and definition. The proper name of this product shall be Antibody to Hepatitis B Surface Antigen. The product is...

  10. Human antibody and antigen response to IncA antibody of Chlamydia trachomatis.

    Science.gov (United States)

    Tsai, P Y; Hsu, M C; Huang, C T; Li, S Y

    2007-01-01

    The high prevalence of C. trachomatis worldwide has underscored the importance of identifying specific immunogenic antigens in facilitating diagnosis as well as vaccine development. The aim of this study is to evaluate IncA antibody and antigen production in natural human infections. Our temporal expression study showed that IncA transcription and protein expression could be detected as early as 4 hours after the start of infection. Antibody responses could be detected in urine and genital swab samples from C. trachomatis-positive patients. It is especially interesting to note that the IncA antigen could be detected in urine. In conclusion, we have identified IncA as an important antigen in human. The potential applicability of the IncA antibody or antigen in the diagnosis as well as to vaccine development for C. trachomatis is also discussed.

  11. Evaluation of an Antigen-Antibody

    African Journals Online (AJOL)

    GB

    replication would lead to the production of various antigens. Today with BMT history of over 30 years, infection ... Study design: The study involved both retrospective and prospective laboratory-based analysis of ..... core protein of a molecular mass 19 x 103 Da, one picogram (pg) of virus core corresponds to 1.3 x. 105 HCV ...

  12. The Incidence of Human Cysticercosis in a Rural Community of Eastern Zambia

    OpenAIRE

    Mwape, Kabemba E.; Phiri, Isaac K.; Praet, Nicolas; Speybroeck, Niko; Muma, John B.; Dorny, Pierre; Gabri?l, Sarah

    2013-01-01

    A community-based longitudinal study was performed in the Eastern Province of Zambia, in which repeated serological samplings were done to determine the incidence of human cysticercosis. Three sampling rounds were carried out at six months intervals. A total of 867 participants presented for all three samplings. All samples were tested for the presence of cysticercus antigens using a monoclonal antibody-based enzyme-linked immunosorbent assay (sero-Ag-ELISA), while a randomly selected sub-sam...

  13. Antigenic specificity of serum antibodies in mice fed soy protein

    DEFF Research Database (Denmark)

    Christensen, Hanne Risager; Bruun, S.W.; Frøkiær, Hanne

    2003-01-01

    Background: Soybean protein is used in a number of food products but unfortunately is also a common cause of food allergy. Upon ingestion of soy protein, healthy mice like other animals and humans generate a soy-specific antibody response in the absence of signs of illness. Not much is known about...... the relationship between the immunogenic proteins involved in this nondeleterious antibody response and the pathological response associated with food allergy. The objective of the present study was to characterize the antigenic specificity of the soy protein-specific antibody response generated in healthy mice...... ingesting soy protein. Methods: Blood from mice fed a soy-containing diet was analyzed using ELISA and immunoblot for antibody reactivity towards various soy protein fractions and pure soy proteins/subunits. Mice bred on a soy-free diet were used as controls. Results: The detectable antigenic specificity...

  14. Antigen-antibody reactions of UV-irradiated phage DNA

    International Nuclear Information System (INIS)

    Fink, A.

    1976-01-01

    The observation of others could be confirmed that UV-irradiated DNA is a better immunogen than unirradiated DNA. The author's immune sera contained a high amount of antibodies with a specific action against photoproducts in the DNA. The thymine dimer was identified as relevant photoproduct and thus as antigenic determinant. In comparison, the amount of unspecific antibodies reacting with denaturated DNA was low and varied between sera. Thymin-dimer antibodies showed a high specificity without cross-reaction with other pyrimidine dimers such as anti CC and anti CT; they belong to the class of IgG molecules. UV-irradiated dinucleotide dTpT is sufficient to induce the formation of antibodies reacting with the cis-syn thymine dimers in UV-irradiated DNA. Antibody binding is proportional to the UV doses applied to the DNA. When using completely denaturated DNA, there is a linear increase changing into a plateau at higher doses. The extent of antigen-antibody binding is strongly dependent on the degree of denaturation of the DNA. With increasing denaturation, the antibody binding of the DNA increases. The antigen-antibody reaction can thus be used to estimate the degree of denaturation of the DNA. There were no signs of an influence of the degree of denaturation of the DNA on the quantum yield of thymine dimers. The different amounts of antibodies is therefore due to the masking of thymine dimers in native DNA. When irradiating intact phage particles, there was no sign of an influence of the phages' protein covers on the antibody binding capacity of DNA compared with DNA irradiated in vitro. (orig.) [de

  15. The interfacial character of antibody paratopes: analysis of antibody-antigen structures.

    Science.gov (United States)

    Nguyen, Minh N; Pradhan, Mohan R; Verma, Chandra; Zhong, Pingyu

    2017-10-01

    In this study, computational methods are applied to investigate the general properties of antigen engaging residues of a paratope from a non-redundant dataset of 403 antibody-antigen complexes to dissect the contribution of hydrogen bonds, hydrophobic, van der Waals contacts and ionic interactions, as well as role of water molecules in the antigen-antibody interface. Consistent with previous reports using smaller datasets, we found that Tyr, Trp, Ser, Asn, Asp, Thr, Arg, Gly, His contribute substantially to the interactions between antibody and antigen. Furthermore, antibody-antigen interactions can be mediated by interfacial waters. However, there is no reported comprehensive analysis for a large number of structured waters that engage in higher ordered structures at the antibody-antigen interface. From our dataset, we have found the presence of interfacial waters in 242 complexes. We present evidence that suggests a compelling role of these interfacial waters in interactions of antibodies with a range of antigens differing in shape complementarity. Finally, we carry out 296 835 pairwise 3D structure comparisons of 771 structures of contact residues of antibodies with their interfacial water molecules from our dataset using CLICK method. A heuristic clustering algorithm is used to obtain unique structural similarities, and found to separate into 368 different clusters. These clusters are used to identify structural motifs of contact residues of antibodies for epitope binding. This clustering database of contact residues is freely accessible at http://mspc.bii.a-star.edu.sg/minhn/pclick.html. minhn@bii.a-star.edu.sg, chandra@bii.a-star.edu.sg or zhong_pingyu@immunol.a-star.edu.sg. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  16. Thermodynamics of antibody-antigen interaction revealed by mutation analysis of antibody variable regions.

    Science.gov (United States)

    Akiba, Hiroki; Tsumoto, Kouhei

    2015-07-01

    Antibodies (immunoglobulins) bind specific molecules (i.e. antigens) with high affinity and specificity. In order to understand their mechanisms of recognition, interaction analysis based on thermodynamic and kinetic parameters, as well as structure determination is crucial. In this review, we focus on mutational analysis which gives information about the role of each amino acid residue in antibody-antigen interaction. Taking anti-hen egg lysozyme antibodies and several anti-small molecule antibodies, the energetic contribution of hot-spot and non-hot-spot residues is discussed in terms of thermodynamics. Here, thermodynamics of the contribution from aromatic, charged and hydrogen bond-forming amino acids are discussed, and their different characteristics have been elucidated. The information gives fundamental understanding of the antibody-antigen interaction. Furthermore, the consequences of antibody engineering are analysed from thermodynamic viewpoints: humanization to reduce immunogenicity and rational design to improve affinity. Amino acid residues outside hot-spots in the interface play important roles in these cases, and thus thermodynamic and kinetic parameters give much information about the antigen recognition. Thermodynamic analysis of mutant antibodies thus should lead to advanced strategies to design and select antibodies with high affinity. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

  17. Radioimmunoassay for antibodies against surface membrane antigens using adhering cells

    Energy Technology Data Exchange (ETDEWEB)

    Tax, A; Manson, L A [Wistar Inst. of Anatomy and Biology, Philadelphia, Pa. (USA)

    1976-07-01

    A radioimmunoassay using cells adhering to plastic is described. In this assay, A-10 mammary carcinoma attached to the surface of plastic in microtiter plates were permitted to bind antibody and the bound antibody was detected with purified rabbit /sup 125/I-antimouse-Fab. The bound radioactive material was eluted with glycine-HCl buffer (pH 2.5), and the acid eluates were counted in a gamma counter. This assay can be used to detect cytolic or noncytolic antibody to cell surface antigens in studies with any tumor or normal cell that will adhere to a solid surface.

  18. Monoclonal Antibody Production against Human Spermatozoal Surface Antigens

    Directory of Open Access Journals (Sweden)

    M Jedi-Tehrani

    2005-10-01

    Full Text Available Introduction: As monoclonal antibodies are potential tools for characterization of soluble or cellular surface antigens, use of these proteins has always been considered in infertility and reproduction research. Therefore, in this study, monoclonal antibodies against human sperm surface antigens were produced. Material and Methods: To produce specific clones against human sperm surface antigens, proteins were extracted using solubilization methods. Balb/c mice were immunized intraperitoneally with the proteins using complete Freund’s adjuvant in the first injection and incomplete Adjuvant in the following booster injections. Hybridoma cells producing ASA were cloned by limiting dilution. Results: Five stable ASA producing hybridoma clones were achieved and their antibody isotypes were determined by ELISA. All the isotypes were of IgG class. Their cross reactivity with rat and mice spermatozoa was examined but they did not have any cross reactivity. Conclusion: The produced antibodies can be used in further studies to characterize and evaluate each of the antigens present on human sperm surface and determining their role in fertilization.

  19. Spinal cysticercosis

    International Nuclear Information System (INIS)

    Goedert, A.V.; Silva, S.H.F.

    1990-01-01

    Spinal cysticercosis is an extremely uncommon condition. We have examined four patients with complaints that resembled nervous root compression by disk herniation. Myelography was shown to be an efficient method to evaluate spinal involvement, that was characterized by findings of multiple filling defect images (cysts) plus signs of adhesive arachnoiditis. One cyst was found to be mobile. Because of the recent development of medical treatment, a quick and precise diagnosis is of high importance to determine the prognosis of this condition. (author)

  20. TSOL18 Vaccine Antigen of Taenia solium: Development of Monoclonal Antibodies and Field Testing of the Vaccine in Cameroon

    Directory of Open Access Journals (Sweden)

    Assana, E.

    2010-01-01

    Full Text Available Chapter 1 reviews the literature about the immunological aspects of taeniid cestode infections and the existing vaccines against Taenia solium cysticercosis in pigs. One of the most promising vaccines is TSOL18, a protein that has been identified in the oncosphere of Taenia solium and expressed as a recombinant molecule in E. coli. Repeated experimental trials have shown that this vaccine is able to protect up to 100% of the immunised pigs against a challenge infection with T. solium. Antibodies raised by the vaccine are capable of killing the parasite in in vitro cultures and it is believed that antibody and complement mediated killing of invading parasites is the major protective immune mechanism induced by vaccination with TSOL18. The identification of the villages with a high risk of T. solium infection, which could subsequently be used in the vaccine trial, is reported in chapter 2. A survey was conducted in 150 households owning 1756 pigs in the rural areas of Mayo-Danay division in the far north region of Cameroon. A questionnaire survey was carried out to collect information on the pig farming system and to identify potential risk factors for T. solium cysticercosis infection in pigs. Blood samples were collected from 398 pigs with the aim of estimating the sero-prevalence of Taenia solium cysticercosis. The results showed that 90.7% of the pigs were free roaming during the dry season and that 42.7% of households keeping pigs in the rural areas had no latrine facility. Seventy six percent of the interviewed pig owners affirmed that the members of the household used open field defecation. ELISA for antigen and antibody detection showed an apparent prevalence of porcine cysticercosis of 24.6% and 32.2%, respectively. A Bayesian approach using the conditional dependence between the two diagnostic tests indicated that the true sero-prevalence of cysticercosis in Mayo-Danay was 26.6%. Binary logistic regression analysis indicated that the

  1. Frequency of serum anti-cysticercus antibodies in the population of a rural Brazilian community (Cássia dos Coqueiros, SP determined by ELISA and immunoblotting using Taenia crassiceps antigens

    Directory of Open Access Journals (Sweden)

    BRAGAZZA Lúcia M.

    2002-01-01

    Full Text Available Considering the impact of cysticercosis on public health, especially the neurologic form of the disease, neurocysticercosis (NC, we studied the frequency of positivity of anti-Taenia solium cysticercus antibodies in serum samples from 1,863 inhabitants of Cássia dos Coqueiros, SP, a municipal district located 80 km from Ribeirão Preto, an area considered endemic for cysticercosis. The 1,863 samples were tested by enzyme linked immunosorbent assay (ELISA using an antigenic extract from Taenia crassiceps vesicular fluid (Tcra. The reactive and inconclusive ELISA samples were tested by immunoblotting. Of the 459 samples submitted to immunoblotting, 40 were strongly immunoreactive to the immunodominant 18 and 14 kD peptides. Considering the use of immunoblotting as confirmatory due to its high specificity, the anti-cysticercus serum prevalence in this population was 2.1%.

  2. Mycobacterium leprae antigens involved in human immune responses. I. Identification of four antigens by monoclonal antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Britton, W.J.; Hellqvist, L.; Basten, A.; Raison, R.L.

    1985-12-01

    Four distinct antigens were identified in soluble sonicates of Mycobacterium leprae by using a panel of 11 monoclonal antibodies. Cross-reactivity studies with other mycobacterial species were conducted by using ELISA and immunoblot assays, and demonstrated that determinants on two of the antigens were present in many mycobacteria, whereas the other two were limited in distribution. Competitive inhibition experiments with radiolabeled monoclonal antibodies showed cross-inhibition between antibodies identifying two of the four antigenicbands. These two bands, of M/sub tau/ 4.5 to 6 KD and 30 to 40 KD, were resistant to protease treatment after immunoblotting. In contrast the two other bands of 16 and 70 KD were protease-sensitive. Although all four bands reacted with some human lepromatous leprosy sera in immunoblots, the 4.5 to 6 KD and 30 to 40 KD bands were most prominent. Lepromatous leprosy sera also inhibited the binding of radiolabeled monoclonal antibodies to each of the four antigens, with the mean titer causing 50% inhibition being higher for antibodies reacting with the 4.5 to 6 KD and 30 to 40 KD bands. These findings indicated that all four antigens were involved in the human B cell response to M. leprae.

  3. Mycobacterium leprae antigens involved in human immune responses. I. Identification of four antigens by monoclonal antibodies

    International Nuclear Information System (INIS)

    Britton, W.J.; Hellqvist, L.; Basten, A.; Raison, R.L.

    1985-01-01

    Four distinct antigens were identified in soluble sonicates of Mycobacterium leprae by using a panel of 11 monoclonal antibodies. Cross-reactivity studies with other mycobacterial species were conducted by using ELISA and immunoblot assays, and demonstrated that determinants on two of the antigens were present in many mycobacteria, whereas the other two were limited in distribution. Competitive inhibition experiments with radiolabeled monoclonal antibodies showed cross-inhibition between antibodies identifying two of the four antigenicbands. These two bands, of M/sub tau/ 4.5 to 6 KD and 30 to 40 KD, were resistant to protease treatment after immunoblotting. In contrast the two other bands of 16 and 70 KD were protease-sensitive. Although all four bands reacted with some human lepromatous leprosy sera in immunoblots, the 4.5 to 6 KD and 30 to 40 KD bands were most prominent. Lepromatous leprosy sera also inhibited the binding of radiolabeled monoclonal antibodies to each of the four antigens, with the mean titer causing 50% inhibition being higher for antibodies reacting with the 4.5 to 6 KD and 30 to 40 KD bands. These findings indicated that all four antigens were involved in the human B cell response to M. leprae

  4. Complement-fixing antibodies against denatured HLA and MICA antigens are associated with antibody mediated rejection.

    Science.gov (United States)

    Cai, Junchao; Terasaki, Paul I; Zhu, Dong; Lachmann, Nils; Schönemann, Constanze; Everly, Matthew J; Qing, Xin

    2016-02-01

    We have found antibodies against denatured HLA class I antigens in the serum of allograft recipients which were not significantly associated with graft failure. It is unknown whether transplant recipients also have denatured HLA class II and MICA antibodies. The effects of denatured HLA class I, class II, and MICA antibodies on long-term graft outcome were further investigated based on their ability to fix complement c1q. In this 4-year retrospective cohort study, post-transplant sera from 975 kidney transplant recipients were tested for antibodies against denatured HLA/MICA antigens and these antibodies were further classified based on their ability to fix c1q. Thirty percent of patients had antibodies against denatured HLA class I, II, or MICA antigens. Among them, 8.5% and 21.5% of all patients had c1q-fixing and non c1q-fixing antibodies respectively. There was no significant difference on graft survival between patients with or without antibodies against denatured HLA/MICA. However, when these antibodies were further classified according to their ability to fix c1q, patients with c1q-fixing antibodies had a significantly lower graft survival rate than patients without antibodies or patients with non c1q-fixing antibodies (p=0.008). In 169 patients who lost renal grafts, 44% of them had c1q-fixing antibodies against denatured HLA/MICA antigens, which was significantly higher than that in patients with functioning renal transplants (25%, pantibodies were more significantly associated with graft failure caused by AMR (72.73%) or mixed AMR/CMR (61.9%) as compared to failure due to CMR (35.3%) or other causes (39.2%) (p=0.026). Transplant recipients had antibodies against denatured HLA class I, II, and MICA antigens. However, only c1q-fixing antibodies were associated with graft failure which was related to antibody mediated rejection. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Peripheral neuropathies associated with antibodies directed to intracellular neural antigens.

    Science.gov (United States)

    Antoine, J-C

    2014-10-01

    Antibodies directed to intracellular neural antigens have been mainly described in paraneoplastic peripheral neuropathies and mostly includes anti-Hu and anti-CV2/CRMP5 antibodies. These antibodies occur with different patterns of neuropathy. With anti-Hu antibody, the most frequent manifestation is sensory neuronopathy with frequent autonomic involvement. With anti-CV2/CRMP5 the neuropathy is more frequently sensory and motor with an axonal or mixed demyelinating and axonal electrophysiological pattern. The clinical pattern of these neuropathies is in keeping with the cellular distribution of HuD and CRMP5 in the peripheral nervous system. Although present in high titer, these antibodies are probably not directly responsible for the neuropathy. Pathological and experimental studies indicate that cytotoxic T-cells are probably the main effectors of the immune response. These disorders contrast with those in which antibodies recognize a cell surface antigen and are probably responsible for the disease. The neuronal cell death and axonal degeneration which result from T-cell mediated immunity explains why treating these disorders remains challenging. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  6. RECOMBINATION OF ANTIBODY POLYPEPTIDE CHAINS IN THE PRESENCE OF ANTIGEN

    Science.gov (United States)

    Metzger, Henry; Mannik, Mart

    1964-01-01

    Conditions were developed by which the separated H and L chains of gamma2 globulins recombined to form four-chained molecules in good yields. In the absence of antigen, anti-2,4-dinitrophenyl (anti-DNP) H chains randomly reassociated with a mixture of antibody and non-specific gamma2 globulin L chains. In the presence of a specific hapten, however, the antibody H chains preferentially interacted with the anti-DNP L chains. Antibody H chain-antibody L chain recombinants formed in the presence of hapten were more active than the corresponding recombinants formed in the absence of hapten. Speculations are made regarding the possible mechanisms and biological significance of these effects. PMID:14247718

  7. Porcine Cysticercosis: Possible Cross-Reactivity of Taenia hydatigena to GP50 Antigen in the Enzyme-Linked Immunoelectrotransfer Blot Assay.

    Science.gov (United States)

    Muro, Claudio; Gomez-Puerta, Luis A; Flecker, Robert H; Gamboa, Ricardo; Barreto, Percy Vilchez; Dorny, Pierre; Tsang, Victor C W; Gilman, Robert H; Gonzalez, Armando E; Garcia, Hector H; O'Neal, Seth E; For The Cysticercosis Working Group In Peru

    2017-12-01

    The lentil lectin glycoprotein enzyme-linked immunoelectrotransfer blot (LLGP EITB, reported sensitivity 99% and specificity 100%) is used as a serologic marker of exposure to Taenia solium in pigs. However, only a limited number of parasites have been evaluated for cross reactivity. Pigs may host other related cestode infections, including Taenia hydatigena, which have not been formally evaluated for cross-reactions. We investigated a corral in Tumbes, Peru, a region where a cysticercosis elimination demonstration project was completed in 2012. In this corral, 14/19 (73.7%) 6-8-week-old piglets were reactive to GP50 on LLGP EITB, and all had circulating Taenia sp. antigens. From eight necropsied piglets; four were infected with T. hydatigena metacestodes whereas none had evidence of T. solium infection. Two resident dogs were subsequently confirmed to have T. hydatigena taeniasis. These results suggest GP50 cross-reactivity in T. hydatigena- infected pigs, although controlled experimental infection is needed to confirm this hypothesis.

  8. Demonstration of two distinct antigenic determinants on hepatitis B e antigen by monoclonal antibodies

    International Nuclear Information System (INIS)

    Imai, M.; Nomura, M.; Gotanda, T.; Sano, T.; Tachibana, K.; Miyamoto, H.; Takahashi, K.; Toyama, S.; Miyakawa, Y.; Mayumi, M.

    1982-01-01

    Mice were immunized against hepatitis B e antigen (HBeAg) isolated from sera of asymptomatic carriers of hepatitis B virus. Their spleen cells were fused with mouse myeloma (NS-1) cells, and 5 clones of hybridoma cells secreting antibody against HBeAg (anti-HBe) were isolated. For the production of anti-HBe in large scale, cells were cultivated both in vitro and in the peritoneal cavity of ascitic mice. Although monoclonal antibodies produced by these clones showed a strong reactivity of anti-HBe in hemagglutination tests, individual monoclonal anti-HBe did not reveal any precipitin line in immunodiffusion. When 2 of the 5 monoclonal antibodies were mixed together, however, some combinations showed a precipitin line against HBeAg, whereas others did not. Utilizing solid-phase radioimmunoassay involving a number of combinations of monoclonal antibodies used for solid-phase and radiolabeling, the 5 antibodies were classified into 2 groups. Three of the anti-HBe antibodies were found to be directed to 1 determinant of HBeAg (determinant a); the remaining 2 to the other determinant (determinant b). Determinants a and b were detected on HBeAg in the serum, as well as on the polypeptide of 19,000 daltons (P19) derived from the nucleocapsid of hepatitis B virus. Monoclonal anti-HBe antibodies with different specificities may provide useful tools in delineating the antigenic structure of HBeAg and also in evaluating immune responses of the host directed to its subdeterminants

  9. Modeling antigen-antibody nanoparticle bioconjugates and their polymorphs

    Science.gov (United States)

    Desgranges, Caroline; Delhommelle, Jerome

    2018-03-01

    The integration of nanomaterials with biomolecules has recently led to the development of new ways of designing biosensors, and through their assembly, to new hybrid structures for novel and exciting applications. In this work, we develop a coarse-grained model for nanoparticles grafted with antibody molecules and their binding with antigens. In particular, we isolate two possible states for antigen-antibody pairs during the binding process, termed as recognition and anchoring states. Using molecular simulation, we calculate the thermodynamic and structural features of three possible crystal structures or polymorphs, the body-centered cubic, simple cubic, and face-centered cubic phases, and of the melt. This leads us to determine the domain of stability of the three solid phases. In particular, the role played by the switching process between anchoring and recognition states during melting is identified, shedding light on the complex microscopic mechanisms in these systems.

  10. Abnormal antigens in breast cancer tissues and production of monoclonal antibodies against one of these antigens

    International Nuclear Information System (INIS)

    Mohammed, M. E. A.

    2010-02-01

    Breast cancer is associated with up regulation, down regulation of normal antigens or abnormal antigens. These antigens are very useful candidates as targets for the different breast cancer therapies and for vaccination trials. This study was done to characterize abnormal antigens, extract one of them and to produce monoclonal antibodies against the extracted antigen. One hundred and twenty Sudanese female patients were included in this study after informed consent. The mean age was 47. 2 years (16-80). Two tissue samples were obtained from each patient and they were confirmed as normal and cancerous breast tissues microscopically. 2D PAGE was used to analyze the protein content of samples. LC/MS and nr. fast a database search were used for separation and indentification of the abnormal proteins. Three different patterns of 2D Page results were obtained, the first pattern involved detection of four abnormal proteins in 26.7% of the patient cancerous tissues while they were undetected in the normal tissues of the same patients. In the second 2D PAGE result pattern the cancerous and the normal tissues of 67.5% patients were identical and they did not contain the four abnormal proteins while the third 2D PAGE pattern involved the presence of two abnormal antigens (from the four) in the cancerous tissues of 5.8% of the patients and they were absent from the normal tissues of the same patients. The four abnormal proteins were identified as, human Thioredoxin (D60nmutant), x-ray crystal structure of human galectin-1, retrocopy of tropomyosin 3(rc TPM3) and beta-tropomyosin (isoform 2). The primary and the secondary structures were obtained from the SWISSPROT and the PDB databases. Beta tropomyosin spot was extracted and used as antigen for monoclonal antibody production. Monoclonal antibody against beta- tropomyosin with a concentration of 0.35 mg/ml and a G11 anti beta-tropomyosin hybridoma cell line were produced. The monoclonal antibody was with single bad and

  11. Abnormal antigens in breast cancer tissues and production of monoclonal antibodies against one of these antigens

    Energy Technology Data Exchange (ETDEWEB)

    Mohammed, M E. A. [University of Khartoum, Khartoum (Sudan)

    2010-02-15

    Breast cancer is associated with up regulation, down regulation of normal antigens or abnormal antigens. These antigens are very useful candidates as targets for the different breast cancer therapies and for vaccination trials. This study was done to characterize abnormal antigens, extract one of them and to produce monoclonal antibodies against the extracted antigen. One hundred and twenty Sudanese female patients were included in this study after informed consent. The mean age was 47. 2 years (16-80). Two tissue samples were obtained from each patient and they were confirmed as normal and cancerous breast tissues microscopically. 2D PAGE was used to analyze the protein content of samples. LC/MS and nr. fast a database search were used for separation and indentification of the abnormal proteins. Three different patterns of 2D Page results were obtained, the first pattern involved detection of four abnormal proteins in 26.7% of the patient cancerous tissues while they were undetected in the normal tissues of the same patients. In the second 2D PAGE result pattern the cancerous and the normal tissues of 67.5% patients were identical and they did not contain the four abnormal proteins while the third 2D PAGE pattern involved the presence of two abnormal antigens (from the four) in the cancerous tissues of 5.8% of the patients and they were absent from the normal tissues of the same patients. The four abnormal proteins were identified as, human Thioredoxin (D60nmutant), x-ray crystal structure of human galectin-1, retrocopy of tropomyosin 3(rc TPM3) and beta-tropomyosin (isoform 2). The primary and the secondary structures were obtained from the SWISSPROT and the PDB databases. Beta tropomyosin spot was extracted and used as antigen for monoclonal antibody production. Monoclonal antibody against beta- tropomyosin with a concentration of 0.35 mg/ml and a G11 anti beta-tropomyosin hybridoma cell line were produced. The monoclonal antibody was with single bad and

  12. Monoclonal antibody against a serotype antigen of Porphyromonas (Bacteroides) endodontalis and characteristics of the antigen.

    Science.gov (United States)

    Hanazawa, S; Sagiya, T; Amano, S; Nishikawa, H; Kitano, S

    1990-01-01

    Recent studies have demonstrated the presence of three serotypes (O1K1, O1K2, and O1K-) of Porphyromonas (Bacteroides) endodontalis. In the present study, a hybridoma cell line producing monoclonal antibody (BEE11) specific for serotype O1K1 of P. endodontalis was established. The specificity of the antibody was evaluated by enzyme-linked immunosorbent assay and immunoslot blot analysis. BEE11 antibody reacted with strains ATCC 35406, HG 400, and HG 421 of the bacterium. However, it did not react with HG 422 or HG 948. Also, the antibody did not react with any of the black-pigmented Bacteroides strains tested. Although the antibody reacted with total cell envelope and capsule materials, it did not do so with lipopolysaccharide. The antibody reacted with antigen material having a molecular mass of 110 kilodaltons (kDa), as judged from fractionation by Superose 12 prep gel chromatography. When the peak fraction from the Superose 12 column was subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blot (immunoblot) analysis, the reactivity was detected as a single band at an apparent molecular mass of about 52 kDa. The antigen material purified partially by high-performance liquid chromatography was sensitive to trypsin, V8 protease, and heating to 80 degrees C but not to neuraminidase. Therefore, the present study shows that BEE11 antibody recognizes a serotype antigen of P. endodontalis which may be a dimer consisting of monomers having molecular masses of approximately 52 kDa and sensitivity to proteases and heat. Images PMID:2370106

  13. Identification of antigen-specific human monoclonal antibodies using high-throughput sequencing of the antibody repertoire.

    Science.gov (United States)

    Liu, Ju; Li, Ruihua; Liu, Kun; Li, Liangliang; Zai, Xiaodong; Chi, Xiangyang; Fu, Ling; Xu, Junjie; Chen, Wei

    2016-04-22

    High-throughput sequencing of the antibody repertoire provides a large number of antibody variable region sequences that can be used to generate human monoclonal antibodies. However, current screening methods for identifying antigen-specific antibodies are inefficient. In the present study, we developed an antibody clone screening strategy based on clone dynamics and relative frequency, and used it to identify antigen-specific human monoclonal antibodies. Enzyme-linked immunosorbent assay showed that at least 52% of putative positive immunoglobulin heavy chains composed antigen-specific antibodies. Combining information on dynamics and relative frequency improved identification of positive clones and elimination of negative clones. and increase the credibility of putative positive clones. Therefore the screening strategy could simplify the subsequent experimental screening and may facilitate the generation of antigen-specific antibodies. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. 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.

  15. Heparin-associated thrombocytopenia: antibody binding specificity to platelet antigens.

    Science.gov (United States)

    Lynch, D M; Howe, S E

    1985-11-01

    Sera from four patients with heparin-associated thrombocytopenia (HAT) were evaluated by a quantitative enzyme-linked immunosorbent assay (ELISA) to detect heparin-dependent serum platelet-bindable immunoglobulin (S-PBIg) and by Western blotting and immunoprecipitation to investigate the specificity of the antibody binding. All HAT sera showed mildly increased S-PBIg (mean, 7.8 fg per platelet; normal, less than 6.0 fg per platelet) to intact target platelets in the ELISA, which was markedly increased in the presence of heparin (mean, 20.9 fg per platelet). This increase was 20-fold greater than normal control sera, which showed a mean differential increase of only 0.5 fg per platelet. Immunoglobulin binding specificity to platelet antigens was investigated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis of platelet lysate with transfer of the platelet fractions onto nitrocellulose strips (Western blotting) and subsequent immunoassay using HAT and normal sera. In the presence of heparin, the four HAT patients demonstrated increased binding of immunoglobulin to platelet antigens of apparent molecular weights of 180, 124, and 82 kd. Radiolabeled heparin when incubated with HAT sera, normal sera, or albumin blanks bound to platelet proteins of the same apparent molecular weights. These observations are consistent with current hypotheses suggesting that HAT antibody is directed to heparin-platelet complexes or, alternatively, that heparin induces conformational change of antigenic sites on the platelet membrane.

  16. 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.

  17. Immunochemical identification of human trophoblast membrane antigens using monoclonal antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Brown, P J; Molloy, C M; Johnson, P M [Liverpool Univ. (UK). Dept. of Immunology

    1983-11-01

    Human trophoblast membrane antigens recognised by monoclonal antibodies (H310, H315, H316 and H317) have been identified using combinations of radioimmunoprecipitation, SDS-PAGE, electroblotting, chromatographic and ELISA-type techniques. H317 is known to identify heat-stable placental-type alkaline phosphatase and accordingly was shown to react with a protein of subunit Msub(r) of 68000. H310 and H316 both recognise an antigen with a subunit Msub(r) of 34000 under reducing conditions. In non-reducing conditions, the H310/316 antigen gave oligomers of a component of Msub(r) 62000. It is unknown whether this 62000 dalton component is a dimer of the 34000 dalton protein with either itself or a second protein chain of presumed Msub(r) around 28000. H315 recognises an antigen with subunit Msub(r) of 36000; in non-reducing conditions this component readily associates to oligomeric structures. The epitope recognised by H315 may be sensitive to SDS. The two proteins recognised by H310/316 and H315 have been termed the p34 and p36 trophoblast membrane proteins, respectively.

  18. Induced refolding of a temperature denatured llama heavy-chain antibody fragment by its antigen

    NARCIS (Netherlands)

    Dolk, E.; Vliet, C. van; Perez, J.M.J.; Vriend, G.; Darbon, H.; Ferrat, G.; Cambillau, C.; Frenken, L.G.J.; Verrips, T.

    2005-01-01

    In a previous study we have shown that llama VHH antibody fragments are able to bind their antigen after a heat shock of 90°C, in contrast to the murine monoclonal antibodies. However, the molecular mechanism by which antibody:antigen interaction occurs under these extreme conditions remains

  19. New monoclonal antibodies to rat testicular antigen, TEC-21

    Czech Academy of Sciences Publication Activity Database

    Hálová, Ivana; Dráberová, Lubica; Dráber, Petr

    2001-01-01

    Roč. 47, č. 5 (2001), s. 180-182 ISSN 0015-5500 R&D Projects: GA ČR GV312/96/K205; GA ČR GA204/00/0204; GA ČR GA310/00/0205; GA AV ČR IAA5052005; GA AV ČR IAA7052006; GA MŠk LN00A026 Institutional research plan: CEZ:AV0Z5052915 Keywords : monoclonal antibody * GPI-anchored * testicular antigen Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.519, year: 2001

  20. Development of Methods to Isolate Recombinant Antibodies Against Prostate Cancer Antigens

    National Research Council Canada - National Science Library

    Williams, Myron

    2000-01-01

    .... Appropriate materials, which include prostate cancer (PCa) cell lines, tissue specimens from radical prostacetomies, and hybridomas producing antibodies specific for pro static antigens have been procured...

  1. Specific binding of antigen-antibody in physiological environments: Measurement, force characteristics and analysis

    Science.gov (United States)

    Gu, Xin; Zhou, Jun; Zhou, Lu; Xie, Shusen; Petti, Lucia; Wang, Shaomin; Wang, Fuyan

    2018-05-01

    The specific recognition of the antigen by the antibody is the crucial step in immunoassays. Measurement and analysis of the specific recognition, including the ways in which it is influenced by external factors are of paramount significance for the quality of the immunoassays. Using prostate-specific antigen (PSA)/anti-PSA antibody and α-fetoprotein (AFP) /anti-AFP antibody as examples, we have proposed a novel solution for measuring the binding forces between the antigens and their corresponding antibodies in different physiological environments by combining laminar flow control technology and optical tweezers technology. On the basis of the experimental results, the different binding forces of PSA/anti-PSA antibody and AFP/anti-AFP antibody in the same phosphate-buffered saline (PBS) environments are analysed by comparing the affinity constant of the two antibodies and the number of antigenic determinants of the two antigens. In different electrolyte environments, the changes of the binding force of antigens-antibodies are explained by the polyelectrolyte effect and hydrophobic interaction. Furthermore, in different pH environments, the changes of binding forces of antigens-antibodies are attributed to the role of the denaturation of protein. The study aims to recognise the antigen-antibody immune mechanism, thus ensuring further understanding of the biological functions of tumour markers, and it promises to be very useful for the clinical diagnosis of early-stage cancer.

  2. Mother-Newborn Pairs in Malawi Have Similar Antibody Repertoires to Diverse Malaria Antigens.

    Science.gov (United States)

    Boudová, Sarah; Walldorf, Jenny A; Bailey, Jason A; Divala, Titus; Mungwira, Randy; Mawindo, Patricia; Pablo, Jozelyn; Jasinskas, Algis; Nakajima, Rie; Ouattara, Amed; Adams, Matthew; Felgner, Philip L; Plowe, Christopher V; Travassos, Mark A; Laufer, Miriam K

    2017-10-01

    Maternal antibodies may play a role in protecting newborns against malaria disease. Plasmodium falciparum parasite surface antigens are diverse, and protection from infection requires allele-specific immunity. Although malaria-specific antibodies have been shown to cross the placenta, the extent to which antibodies that respond to the full repertoire of diverse antigens are transferred from the mother to the infant has not been explored. Understanding the breadth of maternal antibody responses and to what extent these antibodies are transferred to the child can inform vaccine design and evaluation. We probed plasma from cord blood and serum from mothers at delivery using a customized protein microarray that included variants of malaria vaccine target antigens to assess the intensity and breadth of seroreactivity to three malaria vaccine candidate antigens in mother-newborn pairs in Malawi. Among the 33 paired specimens that were assessed, mothers and newborns had similar intensity and repertoire of seroreactivity. Maternal antibody levels against vaccine candidate antigens were the strongest predictors of infant antibody levels. Placental malaria did not significantly impair transplacental antibody transfer. However, mothers with placental malaria had significantly higher antibody levels against these blood-stage antigens than mothers without placental malaria. The repertoire and levels of infant antibodies against a wide range of malaria vaccine candidate antigen variants closely mirror maternal levels in breadth and magnitude regardless of evidence of placental malaria. Vaccinating mothers with an effective malaria vaccine during pregnancy may induce high and potentially protective antibody repertoires in newborns. Copyright © 2017 American Society for Microbiology.

  3. Role of the Antigen Capture Pathway in the Induction of a Neutralizing Antibody Response to Anthrax Protective Antigen

    Directory of Open Access Journals (Sweden)

    Anita Verma

    2018-02-01

    Full Text Available Toxin neutralizing antibodies represent the major mode of protective immunity against a number of toxin-mediated bacterial diseases, including anthrax; however, the cellular mechanisms that lead to optimal neutralizing antibody responses remain ill defined. Here we show that the cellular binding pathway of anthrax protective antigen (PA, the binding component of anthrax toxin, determines the toxin neutralizing antibody response to this antigen. PA, which binds cellular receptors and efficiently enters antigen-presenting cells by receptor-mediated endocytosis, was found to elicit robust anti-PA IgG and toxin neutralizing antibody responses. In contrast, a receptor binding-deficient mutant of PA, which does not bind receptors and only inefficiently enters antigen-presenting cells by macropinocytosis, elicited very poor antibody responses. A chimeric protein consisting of the receptor binding-deficient PA mutant tethered to the binding subunit of cholera toxin, which efficiently enters cells using the cholera toxin receptor rather than the PA receptor, elicited an anti-PA IgG antibody response similar to that elicited by wild-type PA; however, the chimeric protein elicited a poor toxin neutralizing antibody response. Taken together, our results demonstrate that the antigen capture pathway can dictate the magnitudes of the total IgG and toxin neutralizing antibody responses to PA as well as the ratio of the two responses.

  4. Antibodies to early EBV, CMV, and HHV6 antigens in systemic lupus erythematosus patients

    DEFF Research Database (Denmark)

    Rasmussen, N S; Draborg, A H; Nielsen, C T

    2015-01-01

    OBJECTIVES: We investigated the antibody levels against early antigens of Epstein-Barr virus (EBV), cytomegalovirus (CMV), and human herpesvirus 6 (HHV6) in systemic lupus erythematosus (SLE) patients and healthy controls, and further correlated these antibodies to haematology/biochemistry, serol......OBJECTIVES: We investigated the antibody levels against early antigens of Epstein-Barr virus (EBV), cytomegalovirus (CMV), and human herpesvirus 6 (HHV6) in systemic lupus erythematosus (SLE) patients and healthy controls, and further correlated these antibodies to haematology...

  5. 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

  6. 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.

  7. Identification of Eimeria acervulina conoid antigen using chicken monoclonal antibody.

    Science.gov (United States)

    Matsubayashi, Makoto; Minoura, Chisa; Kimura, Shintaro; Tani, Hiroyuki; Furuya, Masaru; Lillehoj, Hyun S; Matsuda, Haruo; Takenaka, Shigeo; Hatta, Takeshi; Tsuji, Naotoshi; Sasai, Kazumi

    2016-11-01

    In the poultry industry, Eimeria spp. is one of the important pathogens which cause significant economic losses. We have previously generated a chicken monoclonal antibody (mAb), 6D-12-G10, with specificity for an antigen located in the apical cytoskeleton of Eimeria acervulina and with cross-reactive among Apicomplexan parasites, including other Eimeria spp., Toxoplasma, Neospora, and Cryptosporidium spp. Furthermore, the protein of Cryptosporidium parvum recognized by the 6D-12-G10 has been identified as elongation factor-1α (EF-1α). In the present study, to identify the target molecule of E. acervulina by the mAb, we performed two-dimensional Western blotting analysis. Finally, we found two positive molecules which are identified as EF-1α and a related protein. Our previous finding using C. parvum and the results in this study suggest that EF-1α could be associated with the invasion facilitated by the cytoskeleton at the apical region of zoites.

  8. Cysticercosis of masseter

    Directory of Open Access Journals (Sweden)

    B Dilip Kumar

    2011-01-01

    Full Text Available Cysticercosis is a parasitic infestation caused by the larval stage of Taenia solium, a cestodic paratise. It is a common disease in developing countries where it is also endemic. The most commonly infested body organs include subcutaneous tissues, brain and skeletal muscles. It is interesting to note that oral lesion of cysticercosis is a rare event. Here we report an isolated lesion of cysticercosis in the masseter muscle.

  9. 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

  10. Generation and characterization of monoclonal antibodies specific for 18 kDa antigen from Taenia solium cysticerci.

    Science.gov (United States)

    Zhang, Shaohua; Luo, Xuenong; Guo, Aijiang; Zhu, Xueliang; Cai, Xuepeng

    2016-07-01

    The gene encoding a mature 18 kDa glycoprotein of Taenia solium cysticerci (Ts18) was cloned and bacterially expressed with a His-tagged fusion protein. Monoclonal antibodies (MAbs) against the recombinant Ts18 antigen were generated in vitro by routine murine hybridoma technique of fusing splenocytes, from BALB/c mice immunized with the vesicular fluid of T. solium cysticerci (TsVF), with mouse myeloma cells (SP2/0). The reactivity and specificity of these MAbs were evaluated by indirect ELISA and immunoblotting techniques. Three stable hybridoma clones, namely 3B11, 6C5, and 6G4, were screened using His-Ts18-based ELISA, and these showed two IgG1 isotypes and one IgM isotype. All MAbs reacted with His-Ts18 at molecular weight (MW) 12.8 kDa and the native antigen at MW 18 kDa in TsVF and whole larval extracts (WLE). In a dot blotting test, MAbs 6C5 and 6G4 showed no obvious cross-reactivity with heterologous vesicular fluids from other taeniid species, including Taenia saginata (TsaVF), Taenia pisiformis (TpVF), Taenia hydatigena (ThVF), Taenia multiceps (TmVF), and Echinococcus granulosus (EgVF). Immunofluorescent assays showed that MAb 6C5 specifically reacted with the Ts18 expressed from pEGFP-N1-Ts18-transfected HeLa cells. Immunolocalization analysis, using MAb 6C5 as a probe, indicated that Ts18 was present at high concentrations in the region of the larval sucker and spiral canal. The results indicate that the Ts18 protein is an abundantly secreted parasite protein and MAbs against it might provide a step forward for improving the diagnosis of porcine cysticercosis. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Experimental radioimmunotherapy with I-131-antibody against a differentiation antigen

    International Nuclear Information System (INIS)

    Badger, C.C.; Krohn, K.A.; Bernstein, I.D.

    1985-01-01

    The authors have previously shown that I-131-labeled antibodies (Ab) against the Thyl.l antigen can care AKR/Cu (Thyl.2+) mice bearing the AKR/J (Thy 1l.1+) SL2 T-cell lymphoma. The authors have now extended these studies to therapy with I-131-anti-Thyl.1 of SL2 lymphoma in AKR/J mice where Ab reacts with both tumor and normal cells. A 25 μg bolus was rapidly cleared from serum by binding to spleen cells (75% with Tl/2 <60 min.) and only low concentrations of Ab(<2% ID/gm) were present in tumor after infusion. Therapy of AKR/J mice bearing established s.c. lymphoma nodules with 1500 μCi I-131-anti-Thyl.1 resulted in complete regression of the nodule in 6/6 animals although tumor eventually regrew and all animals died of metastatic lymphoma. In contrast, I-131-irrelevant Ab given to produce the same amount of whole body radiation (750 μCi) did not affect tumor growth. These studies suggest that radiolabeled-AB against differentiation antigens may be useful for therapy in spite of binding to normal cell populations

  12. A rapid one-step radiometric assay for hepatitis B surface antigen utilising monoclonal antibodies

    International Nuclear Information System (INIS)

    Goodall, A.H.; Meek, F.L.; Waters, J.A.; Miescher, G.C.; Janossy, G.; Thomas, H.C.

    1982-01-01

    A two-site antigen assay for HBsAg has been developed that employs 3 monoclonal antibodies. The antibodies were selected for their high affinity and their particular epitope specificity to establish an assay with a sensitivity for the antigen comparable with that of a conventional assay with heterologous antisera. In addition, by selecting a monoclonal antibody for use as a tracer which does not compete for antigenic binding sites with the solid-phase monoclonal antibodies, it has been possible to perform a two-site assay in a single 1 h incubation step, achieving the same degree of sensitivity. This principle of using monoclonal antibodies in a one-step assay therefore gives advantages of speed and simplicity over assays using heterologous antisera and would be applicable to a variety of antigen assays for which appropriate monoclonal antibodies are available. (Auth.)

  13. Antigen-binding radioimmunoassays for human IgG antibodies to bovine ν-lactoglobulin

    International Nuclear Information System (INIS)

    Turner, M.W.; Paganelli, R.; Levinsky, R.J.; Williams, A.

    1983-01-01

    A double antibody antigen-binding assay for the detection of human IgG antibodies to the bovine milk allergen ν-lactoglobulin is described. The levels of such antibodies in patients with established cows' milk protein intolerance were significantly higher than the levels observed in a healthy control group (P<0.01). The assay showed excellent correlation with a solid phase antigen binding assay (rsub(s) = 0.8, P<0.001). (Auth.)

  14. 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....

  15. Anti-cytotoxic T lymphocyte antigen-4 antibodies in melanoma

    Directory of Open Access Journals (Sweden)

    Tosti G

    2013-10-01

    Full Text Available Giulio Tosti, Emilia Cocorocchio, Elisabetta PennacchioliDivisione Melanomi e Sarcomi, Istituto Europeo di Oncologia, Milano, ItalyAbstract: Approaches aimed at enhancement of the tumor specific response have provided proof for the rationale of immunotherapy in cancer, both in animal models and in humans. Ipilimumab, an anti-cytotoxic T lymphocyte antigen-4 (CTLA-4 antibody, is a new generation immunotherapeutic agent that has shown activity in terms of disease free and overall survival in metastatic melanoma patients. Its use was approved by the US Food and Drug Administration in March 2011 to treat patients with late stage melanoma that has spread or that cannot be removed by surgery. The mechanism of action of CTLA-4 antibodies in the activation of an antitumor immune response and selected clinical studies of ipilimumab in advanced melanoma patients are discussed. Ipilimumab treatment has been associated with immune related adverse events due to T-cell activation and proliferation. Most of these serious adverse effects are associated with the gastrointestinal tract and include severe diarrhea and colitis. The relationship between immune related adverse events and antitumor activity associated with ipilimumab was explored in clinical studies. Potential biomarkers predictive for clinical response and survival in patients treated with anti-CTLA-4 therapy are presently under investigation. Besides the conventional patterns of response and stable disease as defined by standard Response Evaluation Criteria in Solid Tumors criteria, in subsets of patients, ipilimumab has shown patterns of delayed clinical activity which were associated with an improved overall survival. For this reason a new set of response criteria for tumor immunotherapy has been proposed, which was termed immune related response criteria. These new criteria are presently used to better analyze clinical activity of immunotherapeutic regimens. Ipilimumab is currently under

  16. Seroprevalence and risk factors of human cysticercosis and taeniasis prevalence in a highly endemic area of epilepsy in Bangoua, west Cameroon.

    Science.gov (United States)

    Nkouawa, Agathe; Dschanou, Armel Romeo; Moyou-Somo, Roger; Sako, Yasuhito; Ito, Akira

    2017-01-01

    Cysticercosis caused by the larvae of Taenia solium is a serious and emerging threat to public health in the endemic areas as well as in the non-endemic areas. Neurocysticercosis, an affection of the central nervous system is a leading cause of epilepsy in endemic areas. This study was carried out to investigate human cysticercosis, taeniasis and risk factors, and also their association with epilepsy in Bangoua, west Cameroon where epilepsy is highly prevalent. Out of 384 people investigated, 12 (3.1%) exhibited antibody response against low molecular weight antigens of T. solium by ELISA. Immunoblot revealed that six persons (1.6%) were seropositive with the same antigens. Among 61 epileptic patients, only one was seropositive by immunoblot and the study did not find any statistically significant difference (P>0.05) in seropositivity to T. solium between epileptic persons (1/61, 1.6%) and non-epileptic group (5/323, 1.5%). In addition, cysticercosis was associated with households eating pork meat from pigs slaughtered at home, but not with other factors. The risk factors including pig farming, the consumption of pork meat, vegetables, and non-drinkable water were attenuated by the relatively good hygiene and pig husbandry practices of the population. No egg of Taenia was found in stool by microscopic examination. All data obtained in this study suggested that cysticercosis might not be the principal causative agent of epilepsy in this area. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Human antibody responses to Schistosoma mansoni: does antigen directed, isotype restriction result in the production of blocking antibodies?

    Directory of Open Access Journals (Sweden)

    David W. Dunne

    1987-01-01

    Full Text Available After treatment young Kenyan schoolchildren are highly susceptible to reinfection with Schistosoma mansoni. Older children and adults are resistant to reinfection. There is no evidence that this age related resistance is due to a slow development of protective immunological mechanisms, rather, it appears that young children are susceptible because of the presence of blocking antibodies which decline with age, thus allowing the expression of protective responses. Correlations between antibody responses to different stages of the parasite life-cycle suggest that, in young children, antigen directed, isotype restriction of the response against cross-reactive polysaccharide egg antigens results in an ineffectual, or even blocking antibody response to the schistosomulum.

  18. Electron spectroscopic imaging of antigens by reaction with boronated antibodies.

    Science.gov (United States)

    Qualmann, B; Kessels, M M; Klobasa, F; Jungblut, P W; Sierralta, W D

    1996-07-01

    Two small homogeneous markers for electron spectroscopic imaging (ESI) containing eight dodecaborane cages linked to a poly-alpha, epsilon-L-lysine dendrimer were synthesized; one of these was made water soluble by the attachment of a polyether. The markers were coupled to the sulfhydryl group of (monovalent) antibody fragments (Fab') by a homobifunctional cross-linker. While the coupling ratios of the poorly water-soluble compound did not exceed 20%, the polyether-containing variant reacted quantitatively. Its suitability for immunolabelling was tested in a study of the mechanism of the transcellular transport of an administered heterologous protein (bovine serum albumin, BSA) through ileal enterocytes of newborn piglets by endocytotic vesicles in comparison to conventional immunogold reagents. The post-embedding technique was employed. The boronated Fab' gave rise to considerably higher tagging frequencies than seen with immunogold, as could be expected from its form- and size-related physical advantages and the dense packing of BSA in the vesicles. The new probe, carrying the antigen-combining cleft at one end and the boron clusters at the opposite end of the oval-shaped conjugate, add to the potential of ESI-based immunocytochemistry.

  19. Improved performance of a double antibody radioimmunoassay for carcinoembryonic antigen

    International Nuclear Information System (INIS)

    Zimmerman, R.

    1979-01-01

    A new double antibody solid-phase radioimmunoassay (RIA) for carcinoembryonic antigen (CEA) is critically analyzed. The aim of the study was 4-fold: (a) to define the level of sensitivity (a comparison of 3 different assay procedures revealed that the author's sequential assay was more sensitive than most previously reported RIAs, while competitive and non-equilibrium assay had wider measuring ranges); (b) to analyze recoveries of CEA in either serum, plasma or urine (the recovery , even in urine, was very close to expected values, indicating that no CEA is lost or degraded during brief storage or in the extraction procedure); (c) to evaluate inter- and intra-assay variations, since most clinical management is dependent on serial assays rather than single determinations. The coefficients of variation were low both within and between assays. A change of 3 ng CEA is required for significant change (>2 S.D.) at the normal serum level which is 16 ng CEA/ml in the authors assay. At levels above normal, a change of 4 ng is required; (d) the assay was also developed for determination of CEA levels in a large series of perchlorid acid treated serum, plasma or urine samples. This forms the basis for an assay suitable for serial assays with high sensitivity and accuracy in various neoplastic diseases. (Auth.)

  20. A simplified radioimmunoassay for triiodothyronine (T3) using pre-incubated labelled antigen and antibody

    International Nuclear Information System (INIS)

    Pillai, M.R.A.; Nagvekar, U.H.; Desai, C.N.; Mani, R.S.

    1986-01-01

    The development of a simplified radioimmunoassay for triiodothyronine (T 3 ) using pre-incubated labelled T 3 and antibody is described. The assay is carried out by adding 50 μl of standard or sample to 0.4 ml of pre-incubated reagent dispensed in assay tubes. The reaction was allowed to proceed for about four hours and the antigen-antibody complex precipitated by the addition of 1 cm 3 of 22% polyethylene glycol solution. Due to the high dissociation constant of T 3 -antibody complex at 37 deg C, the labelled antigen-antibody complex dissociates and thereby the unlabelled antigen binds with the antibody. The sensitivity of this assay is comparable to an assay done by the equilibrium method using the same antibody. Sixty serum samples were analyzed using this method and were compared with the equilibrium assay. (author)

  1. Rapid profiling of the antigen regions recognized by serum antibodies using massively parallel sequencing of antigen-specific libraries.

    KAUST Repository

    Domina, Maria; Lanza Cariccio, Veronica; Benfatto, Salvatore; D'Aliberti, Deborah; Venza, Mario; Borgogni, Erica; Castellino, Flora; Biondo, Carmelo; D'Andrea, Daniel; Grassi, Luigi; Tramontano, Anna; Teti, Giuseppe; Felici, Franco; Beninati, Concetta

    2014-01-01

    There is a need for techniques capable of identifying the antigenic epitopes targeted by polyclonal antibody responses during deliberate or natural immunization. Although successful, traditional phage library screening is laborious and can map only some of the epitopes. To accelerate and improve epitope identification, we have employed massive sequencing of phage-displayed antigen-specific libraries using the Illumina MiSeq platform. This enabled us to precisely identify the regions of a model antigen, the meningococcal NadA virulence factor, targeted by serum antibodies in vaccinated individuals and to rank hundreds of antigenic fragments according to their immunoreactivity. We found that next generation sequencing can significantly empower the analysis of antigen-specific libraries by allowing simultaneous processing of dozens of library/serum combinations in less than two days, including the time required for antibody-mediated library selection. Moreover, compared with traditional plaque picking, the new technology (named Phage-based Representation OF Immuno-Ligand Epitope Repertoire or PROFILER) provides superior resolution in epitope identification. PROFILER seems ideally suited to streamline and guide rational antigen design, adjuvant selection, and quality control of newly produced vaccines. Furthermore, this method is also susceptible to find important applications in other fields covered by traditional quantitative serology.

  2. Rapid profiling of the antigen regions recognized by serum antibodies using massively parallel sequencing of antigen-specific libraries.

    Directory of Open Access Journals (Sweden)

    Maria Domina

    Full Text Available There is a need for techniques capable of identifying the antigenic epitopes targeted by polyclonal antibody responses during deliberate or natural immunization. Although successful, traditional phage library screening is laborious and can map only some of the epitopes. To accelerate and improve epitope identification, we have employed massive sequencing of phage-displayed antigen-specific libraries using the Illumina MiSeq platform. This enabled us to precisely identify the regions of a model antigen, the meningococcal NadA virulence factor, targeted by serum antibodies in vaccinated individuals and to rank hundreds of antigenic fragments according to their immunoreactivity. We found that next generation sequencing can significantly empower the analysis of antigen-specific libraries by allowing simultaneous processing of dozens of library/serum combinations in less than two days, including the time required for antibody-mediated library selection. Moreover, compared with traditional plaque picking, the new technology (named Phage-based Representation OF Immuno-Ligand Epitope Repertoire or PROFILER provides superior resolution in epitope identification. PROFILER seems ideally suited to streamline and guide rational antigen design, adjuvant selection, and quality control of newly produced vaccines. Furthermore, this method is also susceptible to find important applications in other fields covered by traditional quantitative serology.

  3. Rapid profiling of the antigen regions recognized by serum antibodies using massively parallel sequencing of antigen-specific libraries.

    KAUST Repository

    Domina, Maria

    2014-12-04

    There is a need for techniques capable of identifying the antigenic epitopes targeted by polyclonal antibody responses during deliberate or natural immunization. Although successful, traditional phage library screening is laborious and can map only some of the epitopes. To accelerate and improve epitope identification, we have employed massive sequencing of phage-displayed antigen-specific libraries using the Illumina MiSeq platform. This enabled us to precisely identify the regions of a model antigen, the meningococcal NadA virulence factor, targeted by serum antibodies in vaccinated individuals and to rank hundreds of antigenic fragments according to their immunoreactivity. We found that next generation sequencing can significantly empower the analysis of antigen-specific libraries by allowing simultaneous processing of dozens of library/serum combinations in less than two days, including the time required for antibody-mediated library selection. Moreover, compared with traditional plaque picking, the new technology (named Phage-based Representation OF Immuno-Ligand Epitope Repertoire or PROFILER) provides superior resolution in epitope identification. PROFILER seems ideally suited to streamline and guide rational antigen design, adjuvant selection, and quality control of newly produced vaccines. Furthermore, this method is also susceptible to find important applications in other fields covered by traditional quantitative serology.

  4. 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.

  5. Taeniasis-cysticercosis in Southern Ecuador: assessment of infection status using multiple laboratory diagnostic tools

    Directory of Open Access Journals (Sweden)

    R Rodriguez-Hidalgo

    2006-11-01

    Full Text Available Taenia solium-taeniasis and cysticercosis were studied in the human and porcine populations of a rural community in the Southern Ecuadorian Andes. From the 1059 inhabitants, 800 serum samples and 958 stool samples could be collected. In addition, 646 from the estimated 1148 pigs were tongue inspected. Circulating antigen was detected by enzyme linked immunosorbent assay (Ag-ELISA in 2.25% of the human population, whereas intestinal taeniasis was detected in 1.46% by the formalin-ether technique. Following treatment and recovery of tapeworm fragments these were all identified as T. solium. Porcine cysticercosis was diagnosed in 3.56% of the pigs by tongue inspection. In addition, enzyme linked immunoelectrotransfer blot (EITB was performed on a subset group of 100 humans to confirm the results of the Ag-ELISA. One hundred serum samples from pigs were also analysed by EITB. It appeared that 43 and 74% of humans and pigs had antibodies against T. solium cysticerci, respectively. It is concluded that contrary to the high exposure of the human population to T. solium that is suggested by EITB, the number of active cysticercosis cases, diagnosed by Ag-ELISA, was low, which may indicate endemic stability. The further use of complementary diagnostic methods for a better understanding of the epidemiology of T. solium is suggested.

  6. Taeniasis-cysticercosis in Southern Ecuador: assessment of infection status using multiple laboratory diagnostic tools.

    Science.gov (United States)

    Rodriguez-Hidalgo, R; Benitez-Ortiz, W; Praet, N; Saa, L R; Vercruysse, J; Brandt, J; Dorny, P

    2006-11-01

    Taenia solium-taeniasis and cysticercosis were studied in the human and porcine populations of a rural community in the Southern Ecuadorian Andes. From the 1059 inhabitants, 800 serum samples and 958 stool samples could be collected. In addition, 646 from the estimated 1148 pigs were tongue inspected. Circulating antigen was detected by enzyme linked immunosorbent assay (Ag-ELISA) in 2.25% of the human population, whereas intestinal taeniasis was detected in 1.46% by the formalin-ether technique. Following treatment and recovery of tapeworm fragments these were all identified as T. solium. Porcine cysticercosis was diagnosed in 3.56% of the pigs by tongue inspection. In addition, enzyme linked immunoelectrotransfer blot (EITB) was performed on a subset group of 100 humans to confirm the results of the Ag-ELISA. One hundred serum samples from pigs were also analysed by EITB. It appeared that 43 and 74% of humans and pigs had antibodies against T. solium cysticerci, respectively. It is concluded that contrary to the high exposure of the human population to T. solium that is suggested by EITB, the number of active cysticercosis cases, diagnosed by Ag-ELISA, was low, which may indicate endemic stability. The further use of complementary diagnostic methods for a better understanding of the epidemiology of T. solium is suggested.

  7. Cell-free synthesis of functional antibody fragments to provide a structural basis for antibody-antigen interaction.

    Directory of Open Access Journals (Sweden)

    Takayoshi Matsuda

    Full Text Available Growing numbers of therapeutic antibodies offer excellent treatment strategies for many diseases. Elucidation of the interaction between a potential therapeutic antibody and its target protein by structural analysis reveals the mechanism of action and offers useful information for developing rational antibody designs for improved affinity. Here, we developed a rapid, high-yield cell-free system using dialysis mode to synthesize antibody fragments for the structural analysis of antibody-antigen complexes. Optimal synthesis conditions of fragments (Fv and Fab of the anti-EGFR antibody 059-152 were rapidly determined in a day by using a 30-μl-scale unit. The concentration of supplemented disulfide isomerase, DsbC, was critical to obtaining soluble antibody fragments. The optimal conditions were directly applicable to a 9-ml-scale reaction, with linear scalable yields of more than 1 mg/ml. Analyses of purified 059-152-Fv and Fab showed that the cell-free synthesized antibody fragments were disulfide-bridged, with antigen binding activity comparable to that of clinical antibodies. Examination of the crystal structure of cell-free synthesized 059-152-Fv in complex with the extracellular domain of human EGFR revealed that the epitope of 059-152-Fv broadly covers the EGF binding surface on domain III, including residues that formed critical hydrogen bonds with EGF (Asp355EGFR, Gln384EGFR, H409EGFR, and Lys465EGFR, so that the antibody inhibited EGFR activation. We further demonstrated the application of the cell-free system to site-specific integration of non-natural amino acids for antibody engineering, which would expand the availability of therapeutic antibodies based on structural information and rational design. This cell-free system could be an ideal antibody-fragment production platform for functional and structural analysis of potential therapeutic antibodies and for engineered antibody development.

  8. 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.)

  9. ELISA with double antigen sandwich for screening specific serum anti-TP antibody in blood donors

    International Nuclear Information System (INIS)

    Wang Yiqing; Shi Zhixu

    2002-01-01

    Objective: To select a sensitive and specific laboratory examination suitable for screening serum anti-TP antibody in blood donors. Methods: The serum anti-TP antibody in 11271 blood donors were detected using ELISA with double antigen sandwich and the outcomes were compared with those using RPR assay. The conflicting specimen were confirmed by repeating the test with TPHA assay. Results: The positive rates of serum anti-TP antibody by ELISA with double antigen sandwich and RPR was 0.36% (41/11271) and 0.26% (29/11271), respectively. The coincidence of the detecting outcomes by ELISA with double antigen sandwich and RPR with TPHA was 97.5% (40/41) and 63.41%(26/41) respectively. Conclusion: Compared with RPR assay, ELISA with double antigen sandwich has higher sensibility and specificity for screening serum anti-TP antibody in blood donors

  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. Docking of B-cell epitope antigen to specific hepatitis B antibody

    Indian Academy of Sciences (India)

    The interaction of pres1 region of hepatitis B virus B-cell epitope antigen with specific hepatitis B neutralizing monoclonal antibody was examined by docking study. We modelled the 3D complex structure of B-cell epitope antigen residues CTTPAQGNSMFPSCCCTKPTDGNCY by homology modelling and docked it with the ...

  12. Purification of a polyclonal antibody against CD147 for ELISA using antigen-immunoaffinity chromatography

    Science.gov (United States)

    Liu, Shuangshuang; Li, Shasha; Zhang, Yang; Wang, Ye; Zhu, Yumeng; Wang, Bin; Chen, Zhi-Nan

    2017-01-01

    The immunoglobulin superfamily member CD147 is a widely expressed glycoprotein that occurs in both a membrane-spanning and soluble form. Sandwich ELISA is a powerful tool for analyzing soluble antigens. The aim of the present study was to obtain a highly specific polyclonal antibody against human CD147 that can be used for sandwich ELISA analysis. Expression of recombinant CD147 by a eukaryotic expression system was used to immunize rabbits to obtain antiserum. A highly specific polyclonal antibody that was able to detect soluble CD147 in sandwich ELISA was obtained by antigen-immunoaffinity chromatography purification. The purity of rabbit anti-CD147 polyclonal antibodies was ~99%, and ELISA analysis was able to determine the titer of the rabbit anti-CD147 polyclonal antibodies at 1:512,000. The lowest concentration of the standard CD147 antigen that the sandwich ELISA was able to detect was 31.25 pg/ml. The sandwich ELISA system was composed of anti-hepatoma HAb18 monoclonal antibodies and purified rabbit anti-CD147 polyclonal antibodies. The present study demonstrated that antigen-immunoaffinity chromatography may be a good technique for the purification of polyclonal antibodies, which may be used to detect antigen in sandwich ELISAs. PMID:28487989

  13. A radioimmunoassay to screen for antibodies to native conformational antigens and analyse ligand-induced structural states of antigenic proteins

    International Nuclear Information System (INIS)

    Bernotat-Danielowski, S.; Koepsell, H.

    1988-01-01

    A radioimmunoassay is described in which antigenic protein was immobilized by incubating nitrocellulose filters of defined diameter with antigen-containing solutions. Antigenic sites which are sensitive to protein denaturation by drying could be detected with the assay. The assay was also used to screen hybridoma supernatants for antibodies directed against Na + cotransport proteins from renal brush-border membranes. Monoclonal antibodies were selected which showed different binding charactertics depending on whether or not substrates of Na + cotransporters were present. One of the antibodies, which showed different antibody binding after addition of D-glucose or L-lactate, bound to a polypeptide component of the renal N + -D-glucose cotransporter and was able to inhibit Na + gradient-dependent. To investigate the effects of D-glucose and L-lactate on the binding of this antibody concentration dependence was measured. High and low affinity binding sites for D-glucose and L-lactate were characterized thereby demonstrating that the radioimmunoassay permits investigations of the properties of high and low affinity substrate binding sites. (author). refs.; 6 figs.; 2 tabs

  14. Antigen-Specific Antibody Glycosylation Is Regulated via Vaccination

    NARCIS (Netherlands)

    Mahan, Alison E.; Jennewein, Madeleine F.; Suscovich, Todd; Dionne, Kendall; Tedesco, Jacquelynne; Chung, Amy W.; Streeck, Hendrik; Pau, Maria; Schuitemaker, Hanneke; Francis, Don; Fast, Patricia; Laufer, Dagna; Walker, Bruce D.; Baden, Lindsey; Barouch, Dan H.; Alter, Galit

    2016-01-01

    Antibody effector functions, such as antibody-dependent cellular cytotoxicity, complement deposition, and antibody-dependent phagocytosis, play a critical role in immunity against multiple pathogens, particularly in the absence of neutralizing activity. Two modifications to the IgG constant domain

  15. 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 ...

  16. Taeniasis, cysticercosis and echinococcosis in Thailand.

    Science.gov (United States)

    Waikagul, Jitra; Dekumyoy, Paron; Anantaphruti, Malinee T

    2006-01-01

    Taeniasis is one of the major food-borne parasitic zoonoses in Thailand. During the years 1957-1997, the prevalence was low in most parts of the country. Recent (2000-2005) country prevalence was lower than 1%. A high prevalence (5.9%) was found among 1450 villagers from 30 villages in the North, and among 1233 stool samples from 19 provinces in the Northeast (2.8%). Taenia saginata was the dominant species. Cysticercosis in Thailand is somewhat under-reported/recorded. During the period 1965-2005, diagnosis was based on techniques other than serodiagnosis, giving a total of cysticercosis cases of less than 500. However, an immunoblot technique using delipidized cyst antigen showed 314 positive cases out of 754 samples tested in 2000-2005. Reports of neurocysticercosis appeared more often than cutaneous cysticercosis. A total of 24 cases of echinococcosis, mostly hydatid cysts (only 2 cases of alveolar cysts), were recorded during 1936-2005. These records included 3 cases of foreigners seeking surgery in hospitals in Bangkok. Most Thai patients were migrant workers from the Middle East, and only a few cases were indigenous. The prevalence of cysticercosis and echinococcosis is increasing resulting from sensitive modern diagnostic tests. Taeniasis will persist in Thailand as the consumption of raw/half-cooked meat dishes is still a normal practice for Thai people.

  17. Human peripheral blood monocytes display surface antigens recognized by monoclonal antinuclear antibodies

    International Nuclear Information System (INIS)

    Holers, V.M.; Kotzin, B.L.

    1985-01-01

    The authors used monoclonal anti-nuclear autoantibodies and indirect immunofluorescence to examine normal human peripheral blood mononuclear leukocytes for the presence of cell surface nuclear antigens. Only one monoclonal anti-histone antibody (MH-2) was found to bind to freshly isolated PBL, staining approximately 10% of large cells. However, after cells were placed into culture for 16-24 h, a high percentage (up to 60%) of large-sized cells were recognized by an anti-DNA (BWD-1) and several different antihistone monoclonal antibodies (BWH-1, MH-1, and MH-2). These antibodies recognize separate antigenic determinants on chromatin and histones extracted from chromatin. The histone antigen-positive cells were viable, and the monoclonal antibodies could be shown to be binding to the cell surface and not to the nucleus. Using monoclonal antibodies specific for monocytes and T cells, and complement-mediated cytotoxicity, the cells bearing histone antigens were shown to be primarily monocytes. The appearance of histone and DNA antigen-positive cells was nearly completely inhibited by the addition of low concentrations of cycloheximide at initiation of the cultures. In contrast, little effect on the percentage of positive cells was detected if cells were exposed to high doses of gamma irradiation before culture. These data further support the existence of cell surface nuclear antigens on selected cell subsets, which may provide insight into the immunopathogenesis of systemic lupus erythematosus and related autoimmune diseases

  18. Immunoradiometric assay for quantification of serum antibodies to dental plaque antigen in immunized dogs

    International Nuclear Information System (INIS)

    Ahlstedt, S.; Rylander, H.

    1975-01-01

    An immunoradiometric assay (IRMA) was used for quantifying dog serum antibodies to antigens from dental plaque collected from full-grown dogs. The antigens were adsorbed onto the inner surface of plastic tubes and then incubated with dog-anti-plaque serum, 125 I-labelled anti-dog plasma-immunoglobulin was used for quantification of the specific antibodies. Four 10 months old Beagle dogs in excellent gingival health were immunized for 10 weeks with ultrasonicated dog dental plaque. The antibody levels in antisera sampled 6, 8, 10 and 11 weeks after the first antigen injection were 2 to 5 times as high as those recorded before the immunizing period. The variability of the assay as judged from the difference between duplicate samples was found to be 18 percent+-4 (p<0.01) of the mean value and the variability between the same serum ran on different test occasions 13 percent+-7 (p<0.01). The specificity of the antigen-antibody reaction in the immuno assay was tested by inhibition experiments. Preincubation of the antisera with dental plaque antigen significantly inhibited the antigen-antibody reaction in the IRMA, while bovine serum albumin did not. (author)

  19. Immunoradiometric assay for quantification of serum antibodies to dental plaque antigen in immunized dogs

    Energy Technology Data Exchange (ETDEWEB)

    Ahlstedt, S; Rylander, H [Goeteborg Univ. (Sweden)

    1975-01-01

    An immunoradiometric assay (IRMA) was used for quantifying dog serum antibodies to antigens from dental plaque collected from full-grown dogs. The antigens were adsorbed onto the inner surface of plastic tubes and then incubated with dog-anti-plaque serum, /sup 125/I-labelled anti-dog plasma-immunoglobulin was used for quantification of the specific antibodies. Four 10 months old Beagle dogs in excellent gingival health were immunized for 10 weeks with ultrasonicated dog dental plaque. The antibody levels in antisera sampled 6, 8, 10 and 11 weeks after the first antigen injection were 2 to 5 times as high as those recorded before the immunizing period. The variability of the assay as judged from the difference between duplicate samples was found to be 18 percent+-4 (p<0.01) of the mean value and the variability between the same serum ran on different test occasions 13 percent+-7 (p<0.01). The specificity of the antigen-antibody reaction in the immuno assay was tested by inhibition experiments. Preincubation of the antisera with dental plaque antigen significantly inhibited the antigen-antibody reaction in the IRMA, while bovine serum albumin did not.

  20. An MHC-restricted antibody-based chimeric antigen receptor requires TCR-like affinity to maintain antigen specificity

    Directory of Open Access Journals (Sweden)

    Marcela V Maus

    2016-01-01

    Full Text Available Chimeric antigen receptors (CARs are synthetic receptors that usually redirect T cells to surface antigens independent of human leukocyte antigen (HLA. Here, we investigated a T cell receptor-like CAR based on an antibody that recognizes HLA-A*0201 presenting a peptide epitope derived from the cancer-testis antigen NY-ESO-1. We hypothesized that this CAR would efficiently redirect transduced T cells in an HLA-restricted, antigen-specific manner. However, we found that despite the specificity of the soluble Fab, the same antibody in the form of a CAR caused moderate lysis of HLA-A2 expressing targets independent of antigen owing to T cell avidity. We hypothesized that lowering the affinity of the CAR for HLA-A2 would improve its specificity. We undertook a rational approach of mutating residues that, in the crystal structure, were predicted to stabilize binding to HLA-A2. We found that one mutation (DN lowered the affinity of the Fab to T cell receptor-range and restored the epitope specificity of the CAR. DN CAR T cells lysed native tumor targets in vitro, and, in a xenogeneic mouse model implanted with two human melanoma lines (A2+/NYESO+ and A2+/NYESO−, DN CAR T cells specifically migrated to, and delayed progression of, only the HLA-A2+/NY-ESO-1+ melanoma. Thus, although maintaining MHC-restricted antigen specificity required T cell receptor-like affinity that decreased potency, there is exciting potential for CARs to expand their repertoire to include a broad range of intracellular antigens.

  1. Rapid production of antigen-specific monoclonal antibodies from a variety of animals

    Directory of Open Access Journals (Sweden)

    Kurosawa Nobuyuki

    2012-09-01

    Full Text Available Abstract Background Although a variety of animals have been used to produce polyclonal antibodies against antigens, the production of antigen-specific monoclonal antibodies from animals remains challenging. Results We propose a simple and rapid strategy to produce monoclonal antibodies from a variety of animals. By staining lymph node cells with an antibody against immunoglobulin and a fluorescent dye specific for the endoplasmic reticulum, plasma/plasmablast cells were identified without using a series of antibodies against lineage markers. By using a fluorescently labeled antigen as a tag for a complementary cell surface immunoglobulin, antigen-specific plasma/plasmablast cells were sorted from the rest of the cell population by fluorescence-activated cell sorting. Amplification of cognate pairs of immunoglobulin heavy and light chain genes followed by DNA transfection into 293FT cells resulted in the highly efficient production of antigen-specific monoclonal antibodies from a variety of immunized animals. Conclusions Our technology eliminates the need for both cell propagation and screening processes, offering a significant advantage over hybridoma and display strategies.

  2. Immunization Elicits Antigen-Specific Antibody Sequestration in Dorsal Root Ganglia Sensory Neurons

    Science.gov (United States)

    Gunasekaran, Manojkumar; Chatterjee, Prodyot K.; Shih, Andrew; Imperato, Gavin H.; Addorisio, Meghan; Kumar, Gopal; Lee, Annette; Graf, John F.; Meyer, Dan; Marino, Michael; Puleo, Christopher; Ashe, Jeffrey; Cox, Maureen A.; Mak, Tak W.; Bouton, Chad; Sherry, Barbara; Diamond, Betty; Andersson, Ulf; Coleman, Thomas R.; Metz, Christine N.; Tracey, Kevin J.; Chavan, Sangeeta S.

    2018-01-01

    The immune and nervous systems are two major organ systems responsible for host defense and memory. Both systems achieve memory and learning that can be retained, retrieved, and utilized for decades. Here, we report the surprising discovery that peripheral sensory neurons of the dorsal root ganglia (DRGs) of immunized mice contain antigen-specific antibodies. Using a combination of rigorous molecular genetic analyses, transgenic mice, and adoptive transfer experiments, we demonstrate that DRGs do not synthesize these antigen-specific antibodies, but rather sequester primarily IgG1 subtype antibodies. As revealed by RNA-seq and targeted quantitative PCR (qPCR), dorsal root ganglion (DRG) sensory neurons harvested from either naïve or immunized mice lack enzymes (i.e., RAG1, RAG2, AID, or UNG) required for generating antibody diversity and, therefore, cannot make antibodies. Additionally, transgenic mice that express a reporter fluorescent protein under the control of Igγ1 constant region fail to express Ighg1 transcripts in DRG sensory neurons. Furthermore, neural sequestration of antibodies occurs in mice rendered deficient in neuronal Rag2, but antibody sequestration is not observed in DRG sensory neurons isolated from mice that lack mature B cells [e.g., Rag1 knock out (KO) or μMT mice]. Finally, adoptive transfer of Rag1-deficient bone marrow (BM) into wild-type (WT) mice or WT BM into Rag1 KO mice revealed that antibody sequestration was observed in DRG sensory neurons of chimeric mice with WT BM but not with Rag1-deficient BM. Together, these results indicate that DRG sensory neurons sequester and retain antigen-specific antibodies released by antibody-secreting plasma cells. Coupling this work with previous studies implicating DRG sensory neurons in regulating antigen trafficking during immunization raises the interesting possibility that the nervous system collaborates with the immune system to regulate antigen-mediated responses. PMID:29755449

  3. Immunization Elicits Antigen-Specific Antibody Sequestration in Dorsal Root Ganglia Sensory Neurons

    Directory of Open Access Journals (Sweden)

    Manojkumar Gunasekaran

    2018-04-01

    Full Text Available The immune and nervous systems are two major organ systems responsible for host defense and memory. Both systems achieve memory and learning that can be retained, retrieved, and utilized for decades. Here, we report the surprising discovery that peripheral sensory neurons of the dorsal root ganglia (DRGs of immunized mice contain antigen-specific antibodies. Using a combination of rigorous molecular genetic analyses, transgenic mice, and adoptive transfer experiments, we demonstrate that DRGs do not synthesize these antigen-specific antibodies, but rather sequester primarily IgG1 subtype antibodies. As revealed by RNA-seq and targeted quantitative PCR (qPCR, dorsal root ganglion (DRG sensory neurons harvested from either naïve or immunized mice lack enzymes (i.e., RAG1, RAG2, AID, or UNG required for generating antibody diversity and, therefore, cannot make antibodies. Additionally, transgenic mice that express a reporter fluorescent protein under the control of Igγ1 constant region fail to express Ighg1 transcripts in DRG sensory neurons. Furthermore, neural sequestration of antibodies occurs in mice rendered deficient in neuronal Rag2, but antibody sequestration is not observed in DRG sensory neurons isolated from mice that lack mature B cells [e.g., Rag1 knock out (KO or μMT mice]. Finally, adoptive transfer of Rag1-deficient bone marrow (BM into wild-type (WT mice or WT BM into Rag1 KO mice revealed that antibody sequestration was observed in DRG sensory neurons of chimeric mice with WT BM but not with Rag1-deficient BM. Together, these results indicate that DRG sensory neurons sequester and retain antigen-specific antibodies released by antibody-secreting plasma cells. Coupling this work with previous studies implicating DRG sensory neurons in regulating antigen trafficking during immunization raises the interesting possibility that the nervous system collaborates with the immune system to regulate antigen-mediated responses.

  4. Antibody response to the lipopolysaccharide and protein antigens of Salmonella typhi during typhoid infection

    International Nuclear Information System (INIS)

    Tsang, R.S.W.; Chau, P.Y.; Lam, S.K.

    1981-01-01

    Serum antibody responses to the lipopolysaccharide and protein antigens of S. typhi in typhoid patients were studied using a solid-phase radioimmunoassay technique with 125 I labelled anti-immunoglobulin antibody. Sera from 24 adult typhoid patients and 20 non-typhoid adult controls were compared. As a group, sera from typhoid patients showed increased IgA, IgG and IgM immunoglobulin levels and gave significantly higher anti-LPS and anti-protein antibody titres in all three major immunoglobulin classes than did non-typhoid controls. Levels of antibodies against LPS or protein in sera of typhoid patients were highly variable with a skew distribution. A good correlation was found between antibody titres to the LPS antigen and those to a protein antigen. No correlation, however, was found between the anti-LPS antibody titres measured by radioimmunoassay and the anti-O antibody titres measured by the Widal agglutination test. Titration of anti-LPS or anti-protein antibodies by radioimmunoassay was found to be more sensitive and specific than Widal test for the serological diagnosis of typhoid fever. The advantages of measuring antibody response by radioimmunoassay over conventional Widal test are discussed. (author)

  5. Dynamics behind affinity maturation of an anti-HCMV antibody family influencing antigen binding

    KAUST Repository

    Di Palma, Francesco; Tramontano, Anna

    2017-01-01

    The investigation of antibody affinity maturation and its effects on antigen binding is important with respect to understanding the regulation of the immune response. To shed light on this crucial process, we analyzed two Igs neutralizing the human cytomegalovirus: the primary germline antibody M2J1 and its related mature antibody 8F9. Both antibodies target the AD-2S1 epitope of the gB envelope protein and are considered to establish similar interactions with the cognate antigen. We used molecular dynamics simulations to understand the effect of mutations on the antibody–antigen interactions. The results provide a qualitative explanation for the increased 8F9 peptide affinity compared with that of M2J1. The emerging atomistic-detailed description of these complexes reveals the molecular effects of the somatic hypermutations occurring during affinity maturation.

  6. Highly sensitive solid-phase radioimmunoassay for the assay of Plasmodium falciparum antigens and antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Avraham, H.; Golenser, J.; Gazitt, Y.; Spira, D.T.; Sulitzeanu, D. (Hebrew Univ., Jerusalem (Israel). Hadassah Medical School)

    1982-08-27

    A highly sensitive radioimmunoassay for detection of P. falciparum antibodies and antigens is described. A partially purified P. falciparum antigen preparation is obtained from in vitro cultured parasites enriched after gelatin sedimentation by sonicating the infected red blood cells and precipitating the proteins with 50% saturated ammonium sulfate. The precipitate is dissolved in buffer, ultracentrifuged and used to coat wells of microtiter plates. Anti-P. falciparum antibodies are detected by incubating antiserum dilutions in the coated wells and detecting the bound IgG with radioiodinated staphylococcal protein A. P. falciparum antigens are detected by their ability to inhibit binding of antibodies to the coated wells. Sera of individuals with a history of P. falciparum infection contain antibodies detectable at a dilution of 1:75,000. P. falciparum RBC infected in vitro can be detected at levels of parasitemia of the order of 1 parasite or less per 10/sup 6/ RBC.

  7. A highly sensitive solid-phase radioimmunoassay for the assay of Plasmodium falciparum antigens and antibodies

    International Nuclear Information System (INIS)

    Avraham, H.; Golenser, J.; Gazitt, Y.; Spira, D.T.; Sulitzeanu, D.

    1982-01-01

    A highly sensitive radioimmunoassay for detection of P. falciparum antibodies and antigens is described. A partially purified P. falciparum antigen preparation is obtained from in vitro cultured parasites enriched after gelatin sedimentation by sonicating the infected red blood cells and precipitating the proteins with 50% saturated ammonium sulfate. The precipitate is dissolved in buffer, ultracentrifuged and used to coat wells of microtiter plates. Anti-P. falciparum antibodies are detected by incubating antiserum dilutions in the coated wells and detecting the bound IgG with radioiodinated staphylococcal protein A. P. falciparum antigens are detected by their ability to inhibit binding of antibodies to the coated wells. Sera of individuals with a history of P. falciparum infection contain antibodies detectable at a dilution of 1:75,000. P. falciparum RBC infected in vitro can be detected at levels of parasitemia of the order of 1 parasite or less per 10 6 RBC. (Auth.)

  8. Dynamics behind affinity maturation of an anti-HCMV antibody family influencing antigen binding

    KAUST Repository

    Di Palma, Francesco

    2017-08-03

    The investigation of antibody affinity maturation and its effects on antigen binding is important with respect to understanding the regulation of the immune response. To shed light on this crucial process, we analyzed two Igs neutralizing the human cytomegalovirus: the primary germline antibody M2J1 and its related mature antibody 8F9. Both antibodies target the AD-2S1 epitope of the gB envelope protein and are considered to establish similar interactions with the cognate antigen. We used molecular dynamics simulations to understand the effect of mutations on the antibody–antigen interactions. The results provide a qualitative explanation for the increased 8F9 peptide affinity compared with that of M2J1. The emerging atomistic-detailed description of these complexes reveals the molecular effects of the somatic hypermutations occurring during affinity maturation.

  9. 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.

  10. Antibody-antigen-adjuvant conjugates enable co-delivery of antigen and adjuvant to dendritic cells in cis but only have partial targeting specificity.

    Directory of Open Access Journals (Sweden)

    Martin Kreutz

    Full Text Available Antibody-antigen conjugates, which promote antigen-presentation by dendritic cells (DC by means of targeted delivery of antigen to particular DC subsets, represent a powerful vaccination approach. To ensure immunity rather than tolerance induction the co-administration of a suitable adjuvant is paramount. However, co-administration of unlinked adjuvant cannot ensure that all cells targeted by the antibody conjugates are appropriately activated. Furthermore, antigen-presenting cells (APC that do not present the desired antigen are equally strongly activated and could prime undesired responses against self-antigens. We, therefore, were interested in exploring targeted co-delivery of antigen and adjuvant in cis in form of antibody-antigen-adjuvant conjugates for the induction of anti-tumour immunity. In this study, we report on the assembly and characterization of conjugates consisting of DEC205-specific antibody, the model antigen ovalbumin (OVA and CpG oligodeoxynucleotides (ODN. We show that such conjugates are more potent at inducing cytotoxic T lymphocyte (CTL responses than control conjugates mixed with soluble CpG. However, our study also reveals that the nucleic acid moiety of such antibody-antigen-adjuvant conjugates alters their binding and uptake and allows delivery of the antigen and the adjuvant to cells partially independently of DEC205. Nevertheless, antibody-antigen-adjuvant conjugates are superior to antibody-free antigen-adjuvant conjugates in priming CTL responses and efficiently induce anti-tumour immunity in the murine B16 pseudo-metastasis model. A better understanding of the role of the antibody moiety is required to inform future conjugate vaccination strategies for efficient induction of anti-tumour responses.

  11. Production of Antigens and Antibodies for Diagnosis of Arbovirus Diseases.

    Science.gov (United States)

    1994-05-20

    for Germiston, Qalyub, Sicilian, vesicular stomatitis Indiana, and Ganjam viruses. The antigens were inactivated with beta-propiolactone. Rabbits were...vesicular stomatitis Indiana, and Ganjam viruses. The antigens were inactivated with beta-propiolactone. Rabbits were immunized successfully intravenously...370 sm4 6 229 Sicilian Sabin sm37,Vero2 1 23 VS-Indiana Ind. Lab sm7 1 45 Ganjam IG 619 sm5 1 67 Additionally, 22 viruses were passaged in baby mice

  12. Antibody-antigen-adjuvant conjugates enable co-delivery of antigen and adjuvant to dendritic cells in cis but only have partial targeting specificity

    NARCIS (Netherlands)

    Kreutz, M.; Giquel, B.; Hu, Q.; Abuknesha, R.; Uematsu, S.; Akira, S.; Nestle, F.O.; Diebold, S.S.

    2012-01-01

    Antibody-antigen conjugates, which promote antigen-presentation by dendritic cells (DC) by means of targeted delivery of antigen to particular DC subsets, represent a powerful vaccination approach. To ensure immunity rather than tolerance induction the co-administration of a suitable adjuvant is

  13. Antigen-specific cytotoxic T cell and antigen-specific proliferating T cell clones can be induced to cytolytic activity by monoclonal antibodies against T3

    NARCIS (Netherlands)

    Spits, H.; Yssel, H.; Leeuwenberg, J.; de Vries, J. E.

    1985-01-01

    T3 is a human differentiation antigen expressed exclusively on mature T cells. In this study it is shown that anti-T3 monoclonal antibodies, in addition to their capacity to induce T cells to proliferate, are able to induce antigen-specific cytotoxic T lymphocyte clones to mediate antigen

  14. Kinetics of anti-carcinoembryonic antigen antibody internalization: effects of affinity, bivalency, and stability

    Science.gov (United States)

    Schmidt, Michael M.; Thurber, Greg M.

    2010-01-01

    Theoretical analyses suggest that the cellular internalization and catabolism of bound antibodies contribute significantly to poor penetration into tumors. Here we quantitatively assess the internalization of antibodies and antibody fragments against the commonly targeted antigen carcinoembryonic antigen (CEA). Although CEA is often referred to as a non-internalizing or shed antigen, anti-CEA antibodies and antibody fragments are shown to be slowly endocytosed by LS174T cells with a half-time of 10–16 h, a time scale consistent with the metabolic turnover rate of CEA in the absence of antibody. Anti-CEA single chain variable fragments (scFvs) with significant differences in affinity, stability against protease digestion, and valency exhibit similar uptake rates of bound antibody. In contrast, one anti-CEA IgG exhibits unique binding and trafficking properties with twice as many molecules bound per cell at saturation and significantly faster cellular internalization after binding. The internalization rates measured herein can be used in simple computational models to predict the microdistribution of these antibodies in tumor spheroids. PMID:18408925

  15. Rationalization and Design of the Complementarity Determining Region Sequences in an Antibody-Antigen Recognition Interface

    Science.gov (United States)

    Chen, Ing-Chien; Lee, Yu-Ching; Chen, Jun-Bo; Tsai, Keng-Chang; Chen, Ching-Tai; Chang, Jeng-Yih; Yang, Ei-Wen; Hsu, Po-Chiang; Jian, Jhih-Wei; Hsu, Hung-Ju; Chang, Hung-Ju; Hsu, Wen-Lian; Huang, Kai-Fa; Ma, Alex Che; Yang, An-Suei

    2012-01-01

    Protein-protein interactions are critical determinants in biological systems. Engineered proteins binding to specific areas on protein surfaces could lead to therapeutics or diagnostics for treating diseases in humans. But designing epitope-specific protein-protein interactions with computational atomistic interaction free energy remains a difficult challenge. Here we show that, with the antibody-VEGF (vascular endothelial growth factor) interaction as a model system, the experimentally observed amino acid preferences in the antibody-antigen interface can be rationalized with 3-dimensional distributions of interacting atoms derived from the database of protein structures. Machine learning models established on the rationalization can be generalized to design amino acid preferences in antibody-antigen interfaces, for which the experimental validations are tractable with current high throughput synthetic antibody display technologies. Leave-one-out cross validation on the benchmark system yielded the accuracy, precision, recall (sensitivity) and specificity of the overall binary predictions to be 0.69, 0.45, 0.63, and 0.71 respectively, and the overall Matthews correlation coefficient of the 20 amino acid types in the 24 interface CDR positions was 0.312. The structure-based computational antibody design methodology was further tested with other antibodies binding to VEGF. The results indicate that the methodology could provide alternatives to the current antibody technologies based on animal immune systems in engineering therapeutic and diagnostic antibodies against predetermined antigen epitopes. PMID:22457753

  16. Specific Antibodies Reacting with SV40 Large T Antigen Mimotopes in Serum Samples of Healthy Subjects.

    Directory of Open Access Journals (Sweden)

    Mauro Tognon

    Full Text Available Simian Virus 40, experimentally assayed in vitro in different animal and human cells and in vivo in rodents, was classified as a small DNA tumor virus. In previous studies, many groups identified Simian Virus 40 sequences in healthy individuals and cancer patients using PCR techniques, whereas others failed to detect the viral sequences in human specimens. These conflicting results prompted us to develop a novel indirect ELISA with synthetic peptides, mimicking Simian Virus 40 capsid viral protein antigens, named mimotopes. This immunologic assay allowed us to investigate the presence of serum antibodies against Simian Virus 40 and to verify whether Simian Virus 40 is circulating in humans. In this investigation two mimotopes from Simian Virus 40 large T antigen, the viral replication protein and oncoprotein, were employed to analyze for specific reactions to human sera antibodies. This indirect ELISA with synthetic peptides from Simian Virus 40 large T antigen was used to assay a new collection of serum samples from healthy subjects. This novel assay revealed that serum antibodies against Simian Virus 40 large T antigen mimotopes are detectable, at low titer, in healthy subjects aged from 18-65 years old. The overall prevalence of reactivity with the two Simian Virus 40 large T antigen peptides was 20%. This new ELISA with two mimotopes of the early viral regions is able to detect in a specific manner Simian Virus 40 large T antigen-antibody responses.

  17. Topographic antigenic determinants recognized by monoclonal antibodies on human choriogonadotropin beta-subunit

    International Nuclear Information System (INIS)

    Bidart, J.M.; Troalen, F.; Salesse, R.; Bousfield, G.R.; Bohuon, C.J.; Bellet, D.H.

    1987-01-01

    We describe a first attempt to study the antibody-combining sites recognized by monoclonal antibodies raised against the beta-subunit of human choriogonadotropin (hCG). Two groups of antibodies were first defined by their ability to recognize only the free beta-subunit or the free and combined subunit. Antibodies FBT-11 and FBT-11-L bind only to hCG beta-subunit but not to hCG, whereas antibodies FBT-10 and D1E8 bind to both the beta-subunit and the hormone. In both cases, the antigenic determinants were localized to the core of the protein (residues 1-112), indicating the weak immunogenicity of the specific carboxyl-terminal extension of hCG-beta. Nine synthetic peptides spanning different regions of hCG-beta and lutropin-beta were assessed for their capacity to inhibit antibody binding. A synthetic peptide inclusive of the NH2-terminal region (residues 1-7) of the hCG beta-subunit was found to inhibit binding to the radiolabeled subunit of a monoclonal antibody specific for free hCG-beta (FBT-11). Further delineation of the antigenic site recognized by this antibody provided evidence for the involvement of fragment 82-92. Moreover, monoclonal antibody FBT-11 inhibited the recombination of hCG-beta to hCG-alpha, indicating that its antigenic determinant might be located nearby or in the hCG-beta portion interacting with the alpha-subunit. Binding of monoclonal antibody FBT-10, corresponding to the second antigenic determinant, was weakly inhibited by fragment 82-105 and did not impair the recombination of the hCG beta-subunit to the hCG alpha-subunit. Its combining site appeared to be located in a region of the intact native choriogonadotropin present at the surface of the hormone-receptor complex

  18. Enhancing blockade of Plasmodium falciparum erythrocyte invasion: assessing combinations of antibodies against PfRH5 and other merozoite antigens.

    Directory of Open Access Journals (Sweden)

    Andrew R Williams

    Full Text Available No vaccine has yet proven effective against the blood-stages of Plasmodium falciparum, which cause the symptoms and severe manifestations of malaria. We recently found that PfRH5, a P. falciparum-specific protein expressed in merozoites, is efficiently targeted by broadly-neutralizing, vaccine-induced antibodies. Here we show that antibodies against PfRH5 efficiently inhibit the in vitro growth of short-term-adapted parasite isolates from Cambodia, and that the EC(50 values of antigen-specific antibodies against PfRH5 are lower than those against PfAMA1. Since antibody responses elicited by multiple antigens are speculated to improve the efficacy of blood-stage vaccines, we conducted detailed assessments of parasite growth inhibition by antibodies against PfRH5 in combination with antibodies against seven other merozoite antigens. We found that antibodies against PfRH5 act synergistically with antibodies against certain other merozoite antigens, most notably with antibodies against other erythrocyte-binding antigens such as PfRH4, to inhibit the growth of a homologous P. falciparum clone. A combination of antibodies against PfRH4 and basigin, the erythrocyte receptor for PfRH5, also potently inhibited parasite growth. This methodology provides the first quantitative evidence that polyclonal vaccine-induced antibodies can act synergistically against P. falciparum antigens and should help to guide the rational development of future multi-antigen vaccines.

  19. The association of heavy and light chain variable domains in antibodies: implications for antigen specificity.

    KAUST Repository

    Chailyan, Anna

    2011-06-28

    The antigen-binding site of immunoglobulins is formed by six regions, three from the light and three from the heavy chain variable domains, which, on association of the two chains, form the conventional antigen-binding site of the antibody. The mode of interaction between the heavy and light chain variable domains affects the relative position of the antigen-binding loops and therefore has an effect on the overall conformation of the binding site. In this article, we analyze the structure of the interface between the heavy and light chain variable domains and show that there are essentially two different modes for their interaction that can be identified by the presence of key amino acids in specific positions of the antibody sequences. We also show that the different packing modes are related to the type of recognized antigen.

  20. Definition of a virulence-related antigen of Neisseria gonorrhoeae with monoclonal antibodies and lectins.

    Science.gov (United States)

    Demarco de Hormaeche, R; Bundell, C; Chong, H; Taylor, D W; Wildy, P

    1986-03-01

    Variants of one strain of Neisseria gonorrhoeae, grown in vivo or in vitro, that have been previously shown to differ in infectivity, serum resistance, and capsule production were compared with use of monoclonal antibodies and lectins. Monoclonal antibodies to virulent gonococci recognized an antigenic site of the lipopolysaccharide (LPS) produced in large amounts by gonococci grown in vivo but present only in a small proportion of in vitro-grown gonococci. This antigen (C-LPS) was found in all 85 different gonococcal isolates studied but not among nonpathogenic neisseriae. It was shared by group B and C meningococci but not by groups A and D. Enzyme-linked immunosorbent assay and Western blot analysis showed that N-acetylglucosamine and N-acetylgalactosamine form part of the epitope. The C-LPS antigen was shown by immunofluorescence to be present on the surface of the gonococci and also free as slime. This antigen appears to confer resistance to killing by normal sera.

  1. Swine cysticercosis in the Karangasem district of Bali, Indonesia: An evaluation of serological screening methods.

    Science.gov (United States)

    Swastika, Kadek; Dharmawan, Nyoman Sadra; Suardita, I Ketut; Kepeng, I Nengah; Wandra, Toni; Sako, Yasuhito; Okamoto, Munehiro; Yanagida, Tetsuya; Sasaki, Mizuki; Giraudoux, Patrick; Nakao, Minoru; Yoshida, Takahiko; Eka Diarthini, Luh Putu; Sudarmaja, I Made; Purba, Ivan Elisabeth; Budke, Christine M; Ito, Akira

    2016-11-01

    A serological assessment was undertaken on pigs from the Kubu and Abang sub-districts of Karangasem on the island of Bali, Indonesia, where earlier studies had detected patients with cysticercosis. Antigens purified from Taenia solium cyst fluid by cation-exchange chromatography were used to evaluate antibody responses in the pigs and the serological tests were also evaluated using sera from pigs experimentally infected with T. solium eggs. A total of 392 serum samples from naturally exposed pigs were tested using an ELISA that could be read based on both a colour change perceptible by the naked eye and an ELISA based on absorbance values. Twenty six (6.6%) pigs were found seropositive by the naked-eye ELISA and were categorized into three groups: strongly positive (absorbance values >0.8, n=6), moderately positive (absorbance values between 0.2 and 0.8, n=7), and weakly positive (absorbance values Bali were tested using the same ELISA. All 60 pigs were seronegative with no evidence of Taenia infection at necropsy. The results confirm the presence of porcine cysticercosis on Bali and, while the serological responses seen in T. solium infected animals were much stronger than those infected with T. hydatigena, the diagnostic antigens are clearly not species specific. Further studies are necessary to confirm if it is possible to draw a cut off line for differentiation of pig infected with T. solium from those infected with T. hydatigena. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Binding of monoclonal antibody to protein antigen in fluid phase or bound to solid supports

    Energy Technology Data Exchange (ETDEWEB)

    Kennel, S J

    1982-01-01

    Rat monoclonal antibody (MoAb) to fragment D (FgD) of human fibrinogen was used to characterize the direct binding of antibody to protein in solution or bound to solid supports. Purified IgG, F(ab')/sub 2/ and Fab' were prepared from ascites fluid of hybridoma 104-14B which is a fusion product of spleen cells from a rat immunized with FgD and the mouse myeloma cell line, P3-X63-Ag8. Two-dimensional electrophoresis of radioiodinated antibody preparations demonstrated the presence of hybrid immunoglobulin molecules, but only structures having rat heavy and rat light chains had active antibody combinig sites. The affinity constant for IgG as well as F(ab')/sub 2/ and Fab', 6x10/sup 9/ M/sup -1/, was identical when tested using fluid phase antigen (/sup 125/I-labeled FgD). Affinity constants determined for direct binding of iodinated IgG using FgD immobilized on solid supports showed a slight dependence on the antigen concentration used in the measurement. These values ranged from 0.5x10/sup 9/ M/sup -1/ at high antigen concentrations (1.3x10/sup -7/ M) to 9x10/sup 9/ M/sup -1/ at low antigen concentration (1.3x10/sup -10/ M). Binding constants for F(ab')/sub 2/ and Fab' gave similar results indicating that binding was homogeneous and univalent. The capacity of solid state antigen to bind antibody varied with the method used to bind FgD to the solid support. FgD bound directly to polystyrene plates was least efficient at binding labeled antibody; FgD bound to plates through intermediate carriers poly(L-lysine) was only slightly more efficient, while antigen bound to Sepharose beads by cyanogen bromide activation was the most active.

  3. Preparation and Purification of Polyclonal Antibodies against Mycobacterium Avium Paratuberculosis Antigens in Rabbit

    Directory of Open Access Journals (Sweden)

    Hafezeh Alizadeh

    2012-12-01

    Full Text Available Background and Objective: Johne’s disease is the chronic granulomatous enteritis of ruminants, and a major health hazard worldwide. In recent years, researchers have focused on mycobacterium avium subsp. paratuberculosis (MAP antigens in diagnostic tests. Identification of antibodies against MAP antigens is, therefore, effective for the diagnosis or preparation of vaccine. The aim of this study was to prepare and purify polyclonal antibodies against MAP antigens. Materials and Methods: A New Zealand white rabbit was immunized at a certain time period with MAP antigens and Freund’s adjuvant. After the immunization of the animal, the rabbit was bled to obtain enriched serum. Immunoglobulins were obtained via sedimentation with ammonium sulfate 35% and then IgG was purified by ion exchange (DEAE-cellulose chromatography. Serologic test was used to evaluate the interaction of antigens and antibodies. Results: Ion exchange chromatography of IgG showed one peak, and SDS_PAGE of IgG showed a single band. Serologic test was applied and clear precipitation lines were appeared up to 1:16 dilution, which indicated the high quality of the product. Conclusion: In this study, the humoral immune response was induced well by immunization with MAP antigens in a New Zealand white rabbit and polyclonal antibodies were produced in high titers. Polyclonal antibodies are relatively inexpensive and easy to produce in large quantities and can connect to the more connective sites, resulting in better sensitivity. Identification of polyclonal antibodies via immunological tests can play a significant role in studying MAP disorders.

  4. Seroepidemiologic survey of cysticercosis-taeniasis in four central highland districts of Papua, Indonesia.

    Science.gov (United States)

    Salim, Lidwina; Ang, Agnes; Handali, Sukwan; Tsang, Victor C W

    2009-03-01

    Cysticercosis and taeniasis are known to be present in Papua, Indonesia. Several small studies have found a high prevalence of cysticercosis (23.5-56.9%) in the central highlands of Papua. A seroepidemiologic survey was carried out in four districts (Jayawijaya, Paniai, Pegunungan Bintang, and Puncak Jaya) of Papua. Anti-cysticercosis and anti-taeniasis antibodies were measured in 2,931 people using recombinant T24 and recombinant ES33 as a measure of cysticercosis and taeniasis exposures, respectively. Prevalence of cysticercosis-taeniasis is high in the Jayawijaya and Paniai districts (20.8% and 29.2% for cysticercosis and 7% and 9.6% for taeniasis, respectively) and lowest in the other two districts (Pegunungan Bintang and Puncak Jaya) (2% and 2% for cysticercosis and 1.7% and 10.7% for taeniasis, respectively). Our data show that the prevalence of cysticercosis and taeniasis are unchanged from that reported nearly 35 years ago at the beginning of cysticercosis-taeniasis epidemics in Papua, Indonesia.

  5. Trial of using antibodies as carriers of alkylating agents. Pt. 2. Evaluation of ability to form /sup 32/P-cyclophosphamide + immune antibody complexes with homologous antigen

    Energy Technology Data Exchange (ETDEWEB)

    Trzeciak, J; Felus, E; Nolewajka, E; Szaflarski, J; Dudziak, Z [Slaska Akademia Medyczna, Katowice (Poland)

    1976-01-01

    /sup 32/P-cyclophosphamide was found to combine with ..gamma..-globulin fractions of immune sera. Immune sera incubated with /sup 32/P-cyclophosphamide retained ability to react specifically with homologou antigen in vitro in the system: MN antigens of human erythrocytes + rabbit anti-MN antibody, and probably reacted selectively with target antigens in vivo in the system: antigens of guinea pig kidney tissue + rabbit antibodies against these antigens. Hemagglutination, passive hemagglutination and precipitation in agar gel tests were used in the experiments. Ability to combine of the immune antibody + /sup 32/P-cyclophosphamide complex with homologous antigens was evaluated by measurements of radioactivity of studied materials (erythrocyte agglutinates and organ homogenates). The results indicate feasibility of using immune antibodies as carriers of cytostatic agents.

  6. Library of monoclonal antibodies against brush border membrane epithelial antigens

    International Nuclear Information System (INIS)

    Behar, M.; Katz, A.; Silverman, M.

    1986-01-01

    A purified fraction of proximal tubule brush border membranes (BBM) was prepared from dog kidney and used to immunize mice. The standard technique of hybridoma production was followed as described by Kohler and Milstein. Production of antibodies was detected by indirect immunofluorescence on dog kidney slices and by immunodot against the purified fraction on nitrocellulose. Five hybrids exhibited anti BBM activity. These were cloned twice and yielded stable cell lines producing IgG type monoclonal antibodies against BBM. They were designated A 1 , C 7 , D 3 , D 7 and H 4 . As a family these five monoclonals have broad tissue specificity, i.e. positive staining of the surface mucosa of intestinal kidney proximal tubules. D 3 exhibits even broader specificity for epithelium reacting with bile canaliculi and choroid plexus. The authors have verified that at least 4/5 antibodies are directed against BBM protein as revealed by immunoprecipitation of solubilized BBM and detected by Coomassie blue staining or autoradiography of lactoperoxidase labelled BBM. Most interestingly all antibodies bind to the surface of LL CPK 1 cells, a continuous pig kidney cell line of undefined origin but exhibiting many characteristics of proximal tubule cells. The library of monoclonal antibodies obtained provide important probes with which to study membrane biogenesis and polarization in epithelial cells

  7. Monoclonal antibodies to antigens on human neutrophils, activated T lymphocytes, and acute leukemia blast cells

    International Nuclear Information System (INIS)

    Miterev, G.Yu.; Burova, G.F.; Puzhitskaya, M.S.; Danilevich, S.V.; Bulycheva, T.I.

    1987-01-01

    The authors describe the production of two mouse hybridomas secreting monoclonal antibodies to antigenic determinants of the surface membranes of human neutrophils, activated T lymphocytes, and acute leukemic blast cells. The degree of lymphocyte stimulation was estimated from incorporation of 3 H-thymidine with parallel microculture. Monoclonal antibodies of supernatants of hybridoma cultures shown here reacted in both immunofluorescence test and cytotoxicity test with surface membrane antigens on the majority of neutrophils and PHA-activated peripheral blood lymphocytes from healthy subjects, but did not give positive reactions with unactivated lymphocytes, adherent monocytes, erythrocytes, and alloantigen-stimulated lymphocytes

  8. Monoclonal antibodies to antigens on human neutrophils, activated T lymphocytes, and acute leukemia blast cells

    Energy Technology Data Exchange (ETDEWEB)

    Miterev, G.Yu.; Burova, G.F.; Puzhitskaya, M.S.; Danilevich, S.V.; Bulycheva, T.I.

    1987-11-01

    The authors describe the production of two mouse hybridomas secreting monoclonal antibodies to antigenic determinants of the surface membranes of human neutrophils, activated T lymphocytes, and acute leukemic blast cells. The degree of lymphocyte stimulation was estimated from incorporation of /sup 3/H-thymidine with parallel microculture. Monoclonal antibodies of supernatants of hybridoma cultures shown here reacted in both immunofluorescence test and cytotoxicity test with surface membrane antigens on the majority of neutrophils and PHA-activated peripheral blood lymphocytes from healthy subjects, but did not give positive reactions with unactivated lymphocytes, adherent monocytes, erythrocytes, and alloantigen-stimulated lymphocytes.

  9. Immunoglobulin M antibodies against CRA and FRA recombinant antigens of Trypanosoma cruzi in chronic chagasic patients.

    Science.gov (United States)

    Vasconcelos, Romero H T; Azevedo, Elisa A N; Cavalcanti, Maria G A M; Silva, Edimilson D; Ferreira, Antonio G P; Morais, Clarice N L; Gomes, Yara M

    2011-05-01

    Previous works of our research group have demonstrated aspects of the humoral immune response of chronic Chagas disease using the cytoplasmatic repetitive antigen (CRA) and the flagellar repetitive antigen (FRA) of Trypanosoma cruzi. The aim of this work was to analyze the presence of specific immunoglobulin M (IgM) antibodies in chronic chagasic patients using these recombinant antigens of T. cruzi. The positivity of IgM in chronic chagasic patients against CRA and FRA antigens was determined by indirect enzyme-linked immunosorbent assay. We reported no statistical significant differences between the levels of IgM for both recombinant antigens and the different chronic clinical forms of Chagas disease. However, a small proportion of chronic chagasic patients analyzed in this study was positive for this antibody isotype. The findings of this study indicate that the IgM antibodies cannot be used to elucidate the differences in the profile of humoral immune response among chronic chagasic patients with different clinical forms using the CRA and FRA recombinant antigens of T. cruzi. Copyright © 2011 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

  10. Activated human nasal epithelial cells modulate specific antibody response against bacterial or viral antigens.

    Directory of Open Access Journals (Sweden)

    Chiou-Yueh Yeh

    Full Text Available Nasal mucosa is an immune responsive organ evidenced by eliciting both specific local secretory IgA and systemic IgG antibody responses with intra-nasal administration of antigens. Nevertheless, the role of nasal epithelial cells in modulating such responses is unclear. Human nasal epithelial cells (hNECs obtained from sinus mucosa of patients with chronic rhinosinusitis were cultured in vitro and firstly were stimulated by Lactococcus lactis bacterium-like particles (BLPs in order to examine their role on antibody production. Secondly, both antigens of immunodominant protein IDG60 from oral Streptococcus mutans and hemagglutinin (HA from influenza virus were tested to evaluate the specific antibody response. Stimulated hNECs by BLPs exhibited a significant increase in the production of interleukin-6 (IL-6, and thymic stromal lymphopoietin (TSLP. Conditioned medium of stimulated hNECs has effects on enhancing the proliferation of CD4+ T cells together with interferon-γ and IL-5 production, increasing the costimulatory molecules on dendritic cells and augmenting the production of IDG60 specific IgA, HA specific IgG, IgA by human peripheral blood lymphocytes. Such production of antigen specific IgG and IgA is significantly counteracted in the presence of IL-6 and TSLP neutralizing antibodies. In conclusion, properly stimulated hNECs may impart immuno-modulatory effects on the antigen-specific antibody response at least through the production of IL-6 and TSLP.

  11. 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

  12. Analysis of a solid-phase radioimmunoassay for antibodies to cytoplasmic antigen fractions of Candida albicans

    International Nuclear Information System (INIS)

    Mauch, H.; Bromback, J.

    1981-01-01

    An indirect solid-phase radioimmunoassay (SPRIA) in individual polystyrene microtiter cups has been adapted for measurement of antibody to various cytoplasmic and carbohydrate antigen fractions of Candida albicans. The assay was optimized for sensitivity, precision and linearization of serum dilution curves. The optimized procedure allows computerized measurement of anti-Candida antibodies and can be used for measurement of antibody over a wide concentration range. The procedure obviates variation due to changes in day-to-day counts as a result of isotope decay and end-point antibody dilutions. The assay has been used to demonstrate a Poisson-like distribution of antibody levels in the sera of persons showing no symptoms of candidiasis. The minimum antibody level detectable by the assay is about two orders of magnitude lower than the lowest level found in human serum and 4 orders of magnitude lower than the most sensitive test used hitherto, the hemagglutination test. (Auth.)

  13. Radioimmunoassay and some properties of human antibodies to hepatitis B core antigen

    Energy Technology Data Exchange (ETDEWEB)

    Neurath, A R; Szmuness, W; Stevens, C E; Strick, N; Harley, E J [New York Blood Center, N.Y. (USA)

    1978-03-01

    A solid-phase radioimmunoassay for antibodies to hepatitis B core antigen (anti-HBsub(c)) is described. Polystyrene beads coated with anti-HBsub(c), hepatitis B core antigen prepared from pooled sera of humans infected with hepatitis B virus (HBV) and /sup 125/I-labelled anti-HBsub(c) were used for the test. Distinct patterns of development and changes of anti-HBsub(c) and their immunological properties are all related to variations of other markers specific for HBV infections. Knowledge concerning the detailed features of the immune response to hepatitis B core antigen may provide deeper insight into the pathogenesis of HBV infections.

  14. Antibody reaction of human anti-Toxoplasma gondii positive and negative sera with Neospora caninum antigens

    OpenAIRE

    Nam, Ho-Woo; Kang, Seung-Won; Choi, Won-Young

    1998-01-01

    Anti-Neospora caninum antibody was detected in anti-Toxoplasma gondii positive and negative human sera by ELISA, western blot and immunofluorescence assay (IFA). Twelve cases out of 172 (6.7%) Toxoplasma-positive sera cross-reacted with both T. gondii and N. caninum antigens, and one out of 110 Toxoplasma-negative sera reacted with N. caninum antigen by ELISA. By western blot, all 12 sera reacted with T. gondii antigens with various banding patterns but specifically at 30 kDa (SAG1) and 22 kD...

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

    Directory of Open Access Journals (Sweden)

    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.

  16. Lack of radioimmunodetection and complications associated with monoclonal anticarcinoembryonic antigen antibody cross-reactivity with an antigen on circulating cells

    International Nuclear Information System (INIS)

    Dillman, R.O.; Beauregard, J.C.; Sobol, R.E.; Royston, I.; Bartholomew, R.M.; Hagan, P.S.; Halpern, S.E.

    1984-01-01

    Characterization of several high-affinity murine monoclonal anticarcinoembryonic antigen (CEA) antibodies suggested good specificity except for cross-reactivity with an antigen on granulocytes and erythrocytes which was different from the previously described normal cross-reacting antigen of granulocytes. In vivo studies in athymic mice using an indium conjugate of an anti-CEA monoclonal antibody (MoAb) revealed excellent specific uptake in colorectal carcinoma xenografts. Studies were conducted in humans to determine the limitations produced by the cross-reactivity with granulocytes and erythrocytes. Patients with metastatic colorectal cancer received 3 to 6 mg of anti-CEA MoAb over 10 min or 2 hr. In five of six trials, the MoAb infusion was associated with a 40 to 90% decrease in circulating granulocytes and systemic toxicity including fever, rigors, and emesis. One patient had no change in cell count and had no toxicity. Radionuclide scans with 111 In-anti-CEA MoAb showed marked uptake in the spleen when cells were eliminated, and in the liver, especially when pretreatment CEA levels were high. Metastatic tumor sites failed to concentrate the isotope. This study emphasizes the potential limitations for radioimmunodetection and/or radioimmunotherapy imposed by reactivity with circulating cells, and suggests that certain toxic reactions associated with MoAb infusions are related to destruction of circulating cells rather than allergic reactions to mouse protein. It also emphasizes how variables such as dose and binding affinity of antibody, radioisotope used, and assessment at different observation points can obscure lack of antibody specificity

  17. Lack of radioimmunodetection and complications associated with monoclonal anticarcinoembryonic antigen antibody cross-reactivity with an antigen on circulating cells

    Energy Technology Data Exchange (ETDEWEB)

    Dillman, R.O.; Beauregard, J.C.; Sobol, R.E.; Royston, I.; Bartholomew, R.M.; Hagan, P.S.; Halpern, S.E.

    1984-05-01

    Characterization of several high-affinity murine monoclonal anticarcinoembryonic antigen (CEA) antibodies suggested good specificity except for cross-reactivity with an antigen on granulocytes and erythrocytes which was different from the previously described normal cross-reacting antigen of granulocytes. In vivo studies in athymic mice using an indium conjugate of an anti-CEA monoclonal antibody (MoAb) revealed excellent specific uptake in colorectal carcinoma xenografts. Studies were conducted in humans to determine the limitations produced by the cross-reactivity with granulocytes and erythrocytes. Patients with metastatic colorectal cancer received 3 to 6 mg of anti-CEA MoAb over 10 min or 2 hr. In five of six trials, the MoAb infusion was associated with a 40 to 90% decrease in circulating granulocytes and systemic toxicity including fever, rigors, and emesis. One patient had no change in cell count and had no toxicity. Radionuclide scans with /sup 111/In-anti-CEA MoAb showed marked uptake in the spleen when cells were eliminated, and in the liver, especially when pretreatment CEA levels were high. Metastatic tumor sites failed to concentrate the isotope. This study emphasizes the potential limitations for radioimmunodetection and/or radioimmunotherapy imposed by reactivity with circulating cells, and suggests that certain toxic reactions associated with MoAb infusions are related to destruction of circulating cells rather than allergic reactions to mouse protein. It also emphasizes how variables such as dose and binding affinity of antibody, radioisotope used, and assessment at different observation points can obscure lack of antibody specificity.

  18. A novel merozoite surface antigen of Plasmodium falciparum (MSP-3 identified by cellular-antibody cooperative mechanism antigenicity and biological activity of antibodies

    Directory of Open Access Journals (Sweden)

    Claude Oeuvray

    1994-01-01

    Full Text Available We report the identification of a 48kDa antigen targeted by antibodies which inhibit Plasmodium falciparum in vitro growth by cooperation with blood monocytes in an ADCI assay correlated to the naturally acquired protection. This protein is located on the surface of the merozoite stage of P. falciparum, and is detectable in all isolates tested. Epidemiological studies demonstrated that peptides derived from the amino acid sequence of MSP-3 contain potent B and T-cell epitopes recognized by a majority of individuals living in endemic areas. Moreover human antibodies either purified on the recombinant protein, or on the synthetic peptide MSP-3b, as well as antibodies raised in mice, were all found to promote parasite killing mediated by monocytes.

  19. Antibodies against Food Antigens in Patients with Autistic Spectrum Disorders

    Directory of Open Access Journals (Sweden)

    Laura de Magistris

    2013-01-01

    Full Text Available Purpose. Immune system of some autistic patients could be abnormally triggered by gluten/casein assumption. The prevalence of antibodies to gliadin and milk proteins in autistic children with paired/impaired intestinal permeability and under dietary regimen either regular or restricted is reported. Methods. 162 ASDs and 44 healthy children were investigated for intestinal permeability, tissue-transglutaminase (tTG, anti-endomysium antibodies (EMA-IgA, and total mucosal IgA to exclude celiac disease; HLA-DQ2/-DQ8 haplotypes; total systemic antibodies (IgA, IgG, and IgE; specific systemic antibodies: α-gliadin (AGA-IgA and IgG, deamidated–gliadin-peptide (DGP-IgA and IgG, total specific gliadin IgG (all fractions: α, β, γ, and ω, β-lactoglobulin IgG, α-lactalbumin IgG, casein IgG; and milk IgE, casein IgE, gluten IgE, -lactoglobulin IgE, and α-lactalbumin IgE. Results. AGA-IgG and DPG-IgG titers resulted to be higher in ASDs compared to controls and are only partially influenced by diet regimen. Casein IgG titers resulted to be more frequently and significantly higher in ASDs than in controls. Intestinal permeability was increased in 25.6% of ASDs compared to 2.3% of healthy children. Systemic antibodies production was not influenced by paired/impaired intestinal permeability. Conclusions. Immune system of a subgroup of ASDs is triggered by gluten and casein; this could be related either to AGA, DPG, and Casein IgG elevated production or to impaired intestinal barrier function.

  20. Carbamylated albumin is one of the target antigens of anti-carbamylated protein antibodies.

    Science.gov (United States)

    Nakabo, Shuichiro; Hashimoto, Motomu; Ito, Shinji; Furu, Moritoshi; Ito, Hiromu; Fujii, Takao; Yoshifuji, Hajime; Imura, Yoshitaka; Nakashima, Ran; Murakami, Kosaku; Kuramoto, Nobuo; Tanaka, Masao; Satoh, Junko; Ishigami, Akihito; Morita, Satoshi; Mimori, Tsuneyo; Ohmura, Koichiro

    2017-07-01

    Anti-carbamylated protein (anti-CarP) antibodies are detected in RA patients. Fetal calf serum is used as an antigen source in anti-CarP ELISA, and the precise target antigens have not been found. We aimed to identify the target antigens of anti-CarP antibodies. Western blotting of anti-CarP antibodies was conducted. Anti-carbamylated human albumin (CarALB) antibody was detected by in-house ELISA for 493 RA patients and 144 healthy controls (HCs). An inhibition ELISA of anti-CarP antibodies by CarALB and citrullinated albumin (citALB) was performed using eight RA patients' sera. Serum CarALB was detected by liquid chromatography-tandem mass spectroscopy (LC/MS/MS), and the serum MPO concentration was measured by ELISA. We focused on carbamylated albumin because it corresponded to the size of the thickest band detected by western blotting of anti-CarP antibodies. Anti-CarALB antibody was detected in 31.4% of RA patients, and the correlation of the titres between anti-CarALB and anti-CarP was much closer than that between anti-citALB and anti-CCP antibodies (ρ = 0.59 and ρ = 0.16, respectively). The inhibition ELISA showed that anti-CarP antibodies were inhibited by CarALB, but not by citALB. CarALB was detected in sera from RA patients by LC/MS/MS. The serum MPO concentration was correlated with disease activity and was higher in RA patients with anti-CarALB antibody than in those without. We found that carbamylated albumin is a novel target antigen of anti-CarP antibodies, and it is the first reported target antigen that has not been reported as the target of ACPA. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  1. Cysticercosis of the eye in south India - A case series

    Directory of Open Access Journals (Sweden)

    Kaliaperumal S

    2005-01-01

    Full Text Available Purpose: To study the clinical presentation and treatment outcome of patients with ocular cysticercosis in southern India. Methods: This study included 10 patients who were diagnosed to have ocular or adnexal cysticercosis over a period of one year in Pondicherry, India. The clinical presentation, results of investigation and treatment outcome of the cases were analysed retrospectively. Results: Age of these patients ranged from 12 to 55 years. Four presented with loss of vision, two with a swelling in the eyelid, one with proptosis, one with diplopia and two with conjunctival involvement. ELISA for cysticercus antibodies in serum was positive in all cases. Albendazole and prednisolone were given for the treatment of these cases. Two patients responded well to treatment and were completely cured of the disease. There was partial improvement in 6 cases. Surgery in the form of excision was performed in two cases following a course of medical therapy. There was no significant change in visual acuity in eyes with intraocular cysticercosis following treatment. Conclusion: Ultrasonography B scan and ELISA for anticysticercal antibodies help to establish the diagnosis of ocular cysticercosis. A combination of oral albendazole and corticosteroids is found to be effective in confirmed cases. Intraocular cysticercosis is associated with a poor prognosis for vision.

  2. Differential Killing of Salmonella enterica Serovar Typhi by Antibodies Targeting Vi and Lipopolysaccharide O:9 Antigen.

    Directory of Open Access Journals (Sweden)

    Peter J Hart

    Full Text Available Salmonella enterica serovar Typhi expresses a capsule of Vi polysaccharide, while most Salmonella serovars, including S. Enteritidis and S. Typhimurium, do not. Both S. Typhi and S. Enteritidis express the lipopolysaccharide O:9 antigen, yet there is little evidence of cross-protection from anti-O:9 antibodies. Vaccines based on Vi polysaccharide have efficacy against typhoid fever, indicating that antibodies against Vi confer protection. Here we investigate the role of Vi capsule and antibodies against Vi and O:9 in antibody-dependent complement- and phagocyte-mediated killing of Salmonella. Using isogenic Vi-expressing and non-Vi-expressing derivatives of S. Typhi and S. Typhimurium, we show that S. Typhi is inherently more sensitive to serum and blood than S. Typhimurium. Vi expression confers increased resistance to both complement- and phagocyte-mediated modalities of antibody-dependent killing in human blood. The Vi capsule is associated with reduced C3 and C5b-9 deposition, and decreased overall antibody binding to S. Typhi. However, purified human anti-Vi antibodies in the presence of complement are able to kill Vi-expressing Salmonella, while killing by anti-O:9 antibodies is inversely related to Vi expression. Human serum depleted of antibodies to antigens other than Vi retains the ability to kill Vi-expressing bacteria. Our findings support a protective role for Vi capsule in preventing complement and phagocyte killing of Salmonella that can be overcome by specific anti-Vi antibodies, but only to a limited extent by anti-O:9 antibodies.

  3. Differential Killing of Salmonella enterica Serovar Typhi by Antibodies Targeting Vi and Lipopolysaccharide O:9 Antigen.

    Science.gov (United States)

    Hart, Peter J; O'Shaughnessy, Colette M; Siggins, Matthew K; Bobat, Saeeda; Kingsley, Robert A; Goulding, David A; Crump, John A; Reyburn, Hugh; Micoli, Francesca; Dougan, Gordon; Cunningham, Adam F; MacLennan, Calman A

    2016-01-01

    Salmonella enterica serovar Typhi expresses a capsule of Vi polysaccharide, while most Salmonella serovars, including S. Enteritidis and S. Typhimurium, do not. Both S. Typhi and S. Enteritidis express the lipopolysaccharide O:9 antigen, yet there is little evidence of cross-protection from anti-O:9 antibodies. Vaccines based on Vi polysaccharide have efficacy against typhoid fever, indicating that antibodies against Vi confer protection. Here we investigate the role of Vi capsule and antibodies against Vi and O:9 in antibody-dependent complement- and phagocyte-mediated killing of Salmonella. Using isogenic Vi-expressing and non-Vi-expressing derivatives of S. Typhi and S. Typhimurium, we show that S. Typhi is inherently more sensitive to serum and blood than S. Typhimurium. Vi expression confers increased resistance to both complement- and phagocyte-mediated modalities of antibody-dependent killing in human blood. The Vi capsule is associated with reduced C3 and C5b-9 deposition, and decreased overall antibody binding to S. Typhi. However, purified human anti-Vi antibodies in the presence of complement are able to kill Vi-expressing Salmonella, while killing by anti-O:9 antibodies is inversely related to Vi expression. Human serum depleted of antibodies to antigens other than Vi retains the ability to kill Vi-expressing bacteria. Our findings support a protective role for Vi capsule in preventing complement and phagocyte killing of Salmonella that can be overcome by specific anti-Vi antibodies, but only to a limited extent by anti-O:9 antibodies.

  4. A radioimmunoassay for antibodies against surface membrane antigens using adhering cells

    International Nuclear Information System (INIS)

    Tax, A.; Manson, L.A.

    1976-01-01

    A radioimmunoassay using cells adhering to plastic is described. In this assay, A-10 mammary carcinoma attached to the surface of plastic in microtiter plates were permitted to bind antibody and the bound antibody was detected with purified rabbit 125 I-antimouse-Fab. The bound radioactive material was eluted with glycine-HCl buffer (pH 2.5), and the acid eluates were counted in a gamma counter. This assay can be used to detect cytolic or noncytolic antibody to cell surface antigens in studies with any tumor or normal cell that will adhere to a solid surface

  5. An optimized antibody-chelator conjugate for imaging of carcinoembryonic antigen with indium-111

    International Nuclear Information System (INIS)

    Sumerdon, G.A.; Rogers, P.E.; Lombardo, C.M.; Schnobrich, K.E.; Melvin, S.L.; Tribby, I.I.E.; Stroupe, S.D.; Johnson, D.K.; Hobart, E.D.

    1990-01-01

    A monoclonal antibody to carcinoembryonic antigen showing minimal cross-reactivity with blood cells and normal tissues was derivatized with benzylisothiocyanate derivatives of EDTA and DTPA. Seven chelators per immunoglobulin could be incorporated without loss of immunoreactivity. The resulting conjugates, labeled with indium-111, showed low liver uptake in animals. A cold kit, comprising the DTPA conjugate at a molarity of antibody bound chelator exceeding 1 x 10 -4 M, gave radiochemical yields of indium labeled antibody of ≥ 95% and was stable for 1 yr. (author)

  6. 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...

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

    Directory of Open Access Journals (Sweden)

    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.

  8. CARbodies: Human Antibodies Against Cell Surface Tumor Antigens Selected From Repertoires Displayed on T Cell Chimeric Antigen Receptors

    Directory of Open Access Journals (Sweden)

    Vanesa Alonso-Camino

    2013-01-01

    Full Text Available A human single-chain variable fragment (scFv antibody library was expressed on the surface of human T cells after transduction with lentiviral vectors (LVs. The repertoire was fused to a first-generation T cell receptor ζ (TCRζ-based chimeric antigen receptor (CAR. We used this library to isolate antibodies termed CARbodies that recognize antigens expressed on the tumor cell surface in a proof-of-principle system. After three rounds of activation-selection there was a clear repertoire restriction, with the emergence dominant clones. The CARbodies were purified from bacterial cultures as soluble and active proteins. Furthermore, to validate its potential application for adoptive cell therapy, human T cells were transduced with a LV encoding a second-generation costimulatory CAR (CARv2 bearing the selected CARbodies. Transduced human primary T cells expressed significant levels of the CARbodies-based CARv2 fusion protein on the cell surface, and importantly could be specifically activated, after stimulation with tumor cells. This approach is a promising tool for the generation of antibodies fully adapted to the display format (CAR and the selection context (cell synapse, which could extend the scope of current adoptive cell therapy strategies with CAR-redirected T cells.

  9. 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...

  10. Solid phase measurements of antibody and lectin binding to xenogenic carbohydrate antigens

    DEFF Research Database (Denmark)

    Kirkeby, Svend; André, Sabine; Gabius, Hans-Joachim

    2004-01-01

    OBJECTIVES: In future pig-to-man xenotransplantation it is important to master tools that identify potentially xenogenic alphagalactose (Galalpha) antigens in the doner tissue. DESIGN AND METHODS: We have measured the binding potentials of Galalpha detecting lectins and antibodies, including...

  11. Evaluation of an Antigen-Antibody “Combination” Enzyme Linked ...

    African Journals Online (AJOL)

    Conclusion: We conclude that although this assay depicts high sensitivity and specificity in detecting antibodies to HCV, it seems not to add further benefit in our study population to detect HCV infections by enhanced sensitivity due the potential contingency to trace viral capsid antigens. Keywords: Ag-Ab Combination assay ...

  12. Exploring the antigenic response to multiplexed immunizations in a chicken model of antibody production

    DEFF Research Database (Denmark)

    Kousted, Tina Mostrup; Kalliokoski, Otto; Christensen, Sofie Kjellerup

    2017-01-01

    that the competing effects of co-administering multiple immunogens effectively limit the antibody specificities that can be raised in a single individual to a fairly low number. Two potent model immunogens, KLH and CRM197, were administered together with competing antigens in various concentrations and complexities...

  13. Use of Monoclonal Antibodies to Lipopolysaccharide for Antigenic Analysis of Coxiella burnetii

    Science.gov (United States)

    Hotta, Akitoyo; Kawamura, Midori; To, Ho; Andoh, Masako; Yamaguchi, Tsuyoshi; Fukushi, Hideto; Amano, Ken-Ichi; Hirai, Katsuya

    2003-01-01

    Antigenic differences among Coxiella burnetii strains were analyzed. The monoclonal antibodies against the lipopolysaccharide outer core did not react with the strains containing a QpRS plasmid or with plasmidless strains, whereas they reacted with strains containing a QpH1 or QpDV plasmid. C. burnetii isolates could be divided into two groups immunologically. PMID:12682176

  14. Use of Monoclonal Antibodies to Lipopolysaccharide for Antigenic Analysis of Coxiella burnetii

    OpenAIRE

    Hotta, Akitoyo; Kawamura, Midori; To, Ho; Andoh, Masako; Yamaguchi, Tsuyoshi; Fukushi, Hideto; Amano, Ken-Ichi; Hirai, Katsuya

    2003-01-01

    Antigenic differences among Coxiella burnetii strains were analyzed. The monoclonal antibodies against the lipopolysaccharide outer core did not react with the strains containing a QpRS plasmid or with plasmidless strains, whereas they reacted with strains containing a QpH1 or QpDV plasmid. C. burnetii isolates could be divided into two groups immunologically.

  15. 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.

  16. Concurrence of hepatitis B surface antibodies and surface antigen: implications for postvaccination control of health care workers

    NARCIS (Netherlands)

    Zaaijer, Hans L.; Lelie, P. N.; Vandenbroucke-Grauls, C. M. J. E.; Koot, M.

    2002-01-01

    Among 1081 persons testing positive for hepatitis B surface antigen, 106 (10%) tested positive for antibodies to surface antigen (anti-HBs) in the same blood sample. Thirty of these persons were studied in detail: seven tested positive for hepatitis B e-antigen, nine were apparently healthy blood

  17. Prevalence of Hepatitis B Antigen/antibody in Patients of Syphilis

    Directory of Open Access Journals (Sweden)

    B N Joshi

    1980-01-01

    Full Text Available In some cases of Hepatitis B antigen positive hepatitis, a history of previous blood transfusion or any parenteral therapy is lacking and evidence for other routes of infections have to be sought. Sexual contact has been suggested as one of the methods of transmission of this infection. To approach the problem from this angle we studied 480 serawhich werepositive for syphilis serology for the presence of HB antigen and antibody by discontinuous counter immune electrophoresis method. It was found to be prevalent to the extentof 5.Z-per centagainst 1.4 per cent found in voluntary blood donors. Our observation agrees with that of other workers that HB antigen/antibody is seen more frequently in patients with positive syphilis serol-ogy.

  18. Diagnosis of hypersensitivity pneumonitis by measurement of antibodies against environmental antigens

    International Nuclear Information System (INIS)

    Dewair, M.

    1989-01-01

    Hypersensitivity pneumonitis (HP), an immunologically mediated chronic pulmonary disease, is the result of an inflammatory response of the lung initiated by the inhalation of environmental organic dusts. These organic dusts usually contain substances (antigens) capable of eliciting immune responses in humans. The symptoms of HP generally present as recurrent flu-like episodes which makes it difficult to establish the proper diagnosis. However, detection in patients' sera of high-titer antibodies against the environmental antigens could be of great help in identifying those materials causing the disease and which must be avoided. A highly specific and sensitive serodiagnostic test, a radioimmuno assay (RIA), was developed for measurement of antibodies against antigens relevant to Farmer's Lung Disease (FLD), a type of HP affecting farmers

  19. 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

  20. Strong Antibody Responses Induced by Protein Antigens Conjugated onto the Surface of Lecithin-Based Nanoparticles

    Science.gov (United States)

    Sloat, Brian R.; Sandoval, Michael A.; Hau, Andrew M.; He, Yongqun; Cui, Zhengrong

    2009-01-01

    An accumulation of research over the years has demonstrated the utility of nanoparticles as antigen carriers with adjuvant activity. Herein we defined the adjuvanticity of a novel lecithin-based nanoparticle engineered from emulsions. The nanoparticles were spheres of around 200 nm. Model protein antigens, bovine serum albumin (BSA) or Bacillus anthracis protective antigen (PA) protein, were covalently conjugated onto the nanoparticles. Mice immunized with the BSA-conjugated nanoparticles developed strong anti-BSA antibody responses comparable to that induced by BSA adjuvanted with incomplete Freund's adjuvant and 6.5-fold stronger than that induced by BSA adsorbed onto aluminum hydroxide. Immunization of mice with the PA-conjugated nanoparticles elicited a quick, strong, and durable anti-PA antibody response that afforded protection of the mice against a lethal dose of anthrax lethal toxin challenge. The potent adjuvanticity of the nanoparticles was likely due to their ability to move the antigens into local draining lymph nodes, to enhance the uptake of the antigens by antigen-presenting cells (APCs), and to activate APCs. This novel nanoparticle system has the potential to serve as a universal protein-based vaccine carrier capable of inducing strong immune responses. PMID:19729045

  1. The incidence of human cysticercosis in a rural community of Eastern Zambia.

    Science.gov (United States)

    Mwape, Kabemba E; Phiri, Isaac K; Praet, Nicolas; Speybroeck, Niko; Muma, John B; Dorny, Pierre; Gabriël, Sarah

    2013-01-01

    A community-based longitudinal study was performed in the Eastern Province of Zambia, in which repeated serological samplings were done to determine the incidence of human cysticercosis. Three sampling rounds were carried out at six months intervals. A total of 867 participants presented for all three samplings. All samples were tested for the presence of cysticercus antigens using a monoclonal antibody-based enzyme-linked immunosorbent assay (sero-Ag-ELISA), while a randomly selected sub-sample of 161 samples from each sampling round was tested for specific antibodies using a commercial enzyme-linked immunoelectrotransfer blot (EITB) assay. Stool samples (n = 226) were also collected during the final round of sampling for taeniosis diagnosis by coprology and coproantigen ELISA. Cysticercosis seroprevalence varied from 12.2% to 14.5% (sero-Ag) and from 33.5% to 38.5% (sero-Ab) during the study period. A taeniosis prevalence of 11.9% was determined. Incidence rates of 6300 (sero-Ag, per 100000 persons-year) and 23600 (sero-Ab, per 100000 persons-year) were determined. Seroreversion rates of 44% for sero-Ag and 38.7% for sero-Ab were recorded over the whole period. In conclusion, this study has shown the dynamic nature of T. solium infections; many of the people at risk become (re)infected due to the high environmental contamination, with a high number turning seronegative within a year after infection. An important number of infections probably never fully establish, leading to transient antibody responses and short-term antigen presence.

  2. The incidence of human cysticercosis in a rural community of Eastern Zambia.

    Directory of Open Access Journals (Sweden)

    Kabemba E Mwape

    Full Text Available A community-based longitudinal study was performed in the Eastern Province of Zambia, in which repeated serological samplings were done to determine the incidence of human cysticercosis. Three sampling rounds were carried out at six months intervals. A total of 867 participants presented for all three samplings. All samples were tested for the presence of cysticercus antigens using a monoclonal antibody-based enzyme-linked immunosorbent assay (sero-Ag-ELISA, while a randomly selected sub-sample of 161 samples from each sampling round was tested for specific antibodies using a commercial enzyme-linked immunoelectrotransfer blot (EITB assay. Stool samples (n = 226 were also collected during the final round of sampling for taeniosis diagnosis by coprology and coproantigen ELISA. Cysticercosis seroprevalence varied from 12.2% to 14.5% (sero-Ag and from 33.5% to 38.5% (sero-Ab during the study period. A taeniosis prevalence of 11.9% was determined. Incidence rates of 6300 (sero-Ag, per 100000 persons-year and 23600 (sero-Ab, per 100000 persons-year were determined. Seroreversion rates of 44% for sero-Ag and 38.7% for sero-Ab were recorded over the whole period. In conclusion, this study has shown the dynamic nature of T. solium infections; many of the people at risk become (reinfected due to the high environmental contamination, with a high number turning seronegative within a year after infection. An important number of infections probably never fully establish, leading to transient antibody responses and short-term antigen presence.

  3. Human antibody recognition of antigenic site IV on Pneumovirus fusion proteins.

    Science.gov (United States)

    Mousa, Jarrod J; Binshtein, Elad; Human, Stacey; Fong, Rachel H; Alvarado, Gabriela; Doranz, Benjamin J; Moore, Martin L; Ohi, Melanie D; Crowe, James E

    2018-02-01

    Respiratory syncytial virus (RSV) is a major human pathogen that infects the majority of children by two years of age. The RSV fusion (F) protein is a primary target of human antibodies, and it has several antigenic regions capable of inducing neutralizing antibodies. Antigenic site IV is preserved in both the pre-fusion and post-fusion conformations of RSV F. Antibodies to antigenic site IV have been described that bind and neutralize both RSV and human metapneumovirus (hMPV). To explore the diversity of binding modes at antigenic site IV, we generated a panel of four new human monoclonal antibodies (mAbs) and competition-binding suggested the mAbs bind at antigenic site IV. Mutagenesis experiments revealed that binding and neutralization of two mAbs (3M3 and 6F18) depended on arginine (R) residue R429. We discovered two R429-independent mAbs (17E10 and 2N6) at this site that neutralized an RSV R429A mutant strain, and one of these mAbs (17E10) neutralized both RSV and hMPV. To determine the mechanism of cross-reactivity, we performed competition-binding, recombinant protein mutagenesis, peptide binding, and electron microscopy experiments. It was determined that the human cross-reactive mAb 17E10 binds to RSV F with a binding pose similar to 101F, which may be indicative of cross-reactivity with hMPV F. The data presented provide new concepts in RSV immune recognition and vaccine design, as we describe the novel idea that binding pose may influence mAb cross-reactivity between RSV and hMPV. Characterization of the site IV epitope bound by human antibodies may inform the design of a pan-Pneumovirus vaccine.

  4. Core antigen and circulating anti-core antibody in hepatitis B infection

    Energy Technology Data Exchange (ETDEWEB)

    Howard, C R; Zuckerman, A J [London School of Hygiene and Tropical Medicine (UK)

    1977-02-01

    Core antigen was obtained from the sera of persistent chronic carriers of hepatitis B virus by centrifugation and treatment with Nonidet P40 and 2-mercaptoethanol. The separated core antigen was radiolabelled and identified as a nucleoprotein structure of buoyant density 1.36 g/cm/sup 3/ and possessing an isoelectric point of 4.4. This material was employed in a radioimmnoassay procedure of high sensitivity for the detection of core antibody. In a series of sera from patients with acute type B hepatitis, core antibody was demonstrated 2 to 3 weeks after the onset of jaundice during the period of surface antigenaemia. The presence of core antibody may therefore provide an accurate serological marker for the detection of active or recent virus replication in future epidemiological studies of hepatitis B infection.

  5. Development and evaluation of single domain antibodies for vaccinia and the L1 antigen.

    Directory of Open Access Journals (Sweden)

    Scott A Walper

    Full Text Available There is ongoing interest to develop high affinity, thermal stable recognition elements to replace conventional antibodies in biothreat detection assays. As part of this effort, single domain antibodies that target vaccinia virus were developed. Two llamas were immunized with killed viral particles followed by boosts with the recombinant membrane protein, L1, to stimulate the immune response for envelope and membrane proteins of the virus. The variable domains of the induced heavy chain antibodies were selected from M13 phage display libraries developed from isolated RNA. Selection via biopanning on the L1 antigen produced single domain antibodies that were specific and had affinities ranging from 4×10(-9 M to 7.0×10(-10 M, as determined by surface plasmon resonance. Several showed good ability to refold after heat denaturation. These L1-binding single domain antibodies, however, failed to recognize the killed vaccinia antigen. Useful vaccinia binding single domain antibodies were isolated by a second selection using the killed virus as the target. The virus binding single domain antibodies were incorporated in sandwich assays as both capture and tracer using the MAGPIX system yielding limits of detection down to 4×10(5 pfu/ml, a four-fold improvement over the limit obtained using conventional antibodies. This work demonstrates the development of anti-vaccinia single domain antibodies and their incorporation into sandwich assays for viral detection. It also highlights the properties of high affinity and thermal stability that are hallmarks of single domain antibodies.

  6. New monoclonal antibodies to rat testicular antigen, TEC-21

    Czech Academy of Sciences Publication Activity Database

    Hálová, Ivana; Dráberová, Lubica; Dráber, Petr

    2001-01-01

    Roč. 47, č. 5 (2001), s. 180-182 ISSN 0015-5500 R&D Projects: GA ČR GV312/96/K205; GA ČR GA204/00/0204; GA ČR GA310/00/0205; GA AV ČR IAA5052005; GA AV ČR IAA7052006; GA MŠk LN00A026 Keywords : Monoclonal antibody * lipid raft * testicular cells Subject RIV: EC - Immunology Impact factor: 0.519, year: 2001

  7. Standardization and validation of a cytometric bead assay to assess antibodies to multiple Plasmodium falciparum recombinant antigens

    Directory of Open Access Journals (Sweden)

    Ondigo Bartholomew N

    2012-12-01

    Full Text Available Abstract Background Multiplex cytometric bead assay (CBA have a number of advantages over ELISA for antibody testing, but little information is available on standardization and validation of antibody CBA to multiple Plasmodium falciparum antigens. The present study was set to determine optimal parameters for multiplex testing of antibodies to P. falciparum antigens, and to compare results of multiplex CBA to ELISA. Methods Antibodies to ten recombinant P. falciparum antigens were measured by CBA and ELISA in samples from 30 individuals from a malaria endemic area of Kenya and compared to known positive and negative control plasma samples. Optimal antigen amounts, monoplex vs multiplex testing, plasma dilution, optimal buffer, number of beads required were assessed for CBA testing, and results from CBA vs. ELISA testing were compared. Results Optimal amounts for CBA antibody testing differed according to antigen. Results for monoplex CBA testing correlated strongly with multiplex testing for all antigens (r = 0.88-0.99, P values from Conclusion With optimization, CBA may be the preferred method of testing for antibodies to P. falciparum antigens, as CBA can test for antibodies to multiple recombinant antigens from a single plasma sample and produces a greater range of values in positive samples and lower background readings for blank samples than ELISA.

  8. [Knowledge and practices concerning taeniasis-cysticercosis in Colombian pig-breeders].

    Science.gov (United States)

    Agudelo-Flórez, Piedad; Restrepo, Berta N; Palacio, Luis G

    2009-01-01

    Describing knowledge and practices regarding taeniasis-cysticercosis and cysticercosis prevalence in the village of Andagoya, Colombia. The study design was qualitative and quantitative. The study population consisted of pig breeders and their families, local groups and pigs. Study participants had partial knowledge of the taeniasis-cysticercosis complex. They considered taeniasis to be an illness resulting from faecal transmission and not caused by becoming infected with cysticercosis after consuming pork. Pig breeding is not carried out in confined conditions and, although breeders know the right measures for controlling some parasitic illnesses, these practices are not observed. There was 8.7% presence of T. solium antibodies in pig breeders and their relatives and 20.9% in the pigs. An educational programme aimed at raising the population's awareness of the taeniasis-cysticercosis complex cycle should be developed; this will facilitate control measures being applied.

  9. Taeniasis and cysticercosis in housemaids working in affluent neighborhoods in Lima, Peru.

    Science.gov (United States)

    Huisa, Branko N; Menacho, Luis A; Rodriguez, Silvia; Bustos, Javier A; Gilman, Robert H; Tsang, Victor C W; Gonzalez, Armando E; García, Hector H

    2005-09-01

    Taenia solium taeniasis/cysticercosis is endemic in most developing countries, where it is an important cause of epileptic seizures and other neurologic symptoms. In industrialized countries, cysticercosis results from travel or immigration of tapeworm carriers from endemic areas. In both endemic and nonendemic countries, housemaids commonly immigrate from cysticercosis-endemic areas and can transmit the infection if they carry the adult tapeworm. Between July 2001 and July 2002, 1,178 housemaids (961 of them work in the top five most affluent districts of Lima, a metropolis of 8 million inhabitants considered nonendemic for cysticercosis) were evaluated for serum antibodies to Taenia solium and stool microscopy for taeniasis and cysticercosis. The serosurvey revealed a prevalence of cysticercosis-specific antibodies of 14.6% (95% CI: 12.6-16.6%), and stool microscopy detected 12 T. solium tapeworm carriers, for a prevalence of taeniasis of 1.2% (95% CI: 0.6-1.8%). A nonrandom sample of 26 seropositive housemaids was examined by brain CT and 50% of them had brain lesions compatible with neurocysticercosis, mainly calcifications. From the families who used a tapeworm-carrier housemaid, cysticercosis antibodies were detected in 6 (23%) of 26 persons who agreed to participate. One seropositive member of the employer families was symptomatic for seizures and had brain calcifications. The prevalence of tapeworm infections in this housemaid group is similar to levels in endemic areas, constituting a source of neurocysticercosis infection.

  10. Relation between laboratory test results and histological hepatitis activity in individuals positive for hepatitis B surface antigen and antibodies to hepatitis B e antigen

    NARCIS (Netherlands)

    ter Borg, F.; ten Kate, F. J.; Cuypers, H. T.; Leentvaar-Kuijpers, A.; Oosting, J.; Wertheim-van Dillen, P. M.; Honkoop, P.; Rasch, M. C.; de Man, R. A.; van Hattum, J.; Chamuleau, R. A.; Reesink, H. W.; Jones, E. A.

    1998-01-01

    BACKGROUND: Hepatitis B surface antigen (HBsAg) and antibodies to hepatitis B e antigen (anti-HBe) commonly coexist, and laboratory tests are often requested to assess histological hepatitis activity. An optimum panel of tests has not been found and the usefulness of hepatitis B virus (HBV) DNA

  11. Use of monoclonal antibodies against Hendra and Nipah viruses in an antigen capture ELISA

    Directory of Open Access Journals (Sweden)

    Spiropoulou Christina F

    2010-06-01

    Full Text Available Abstract Background Outbreaks of Hendra (HeV and Nipah (NiV viruses have been reported starting in 1994 and 1998, respectively. Both viruses are capable of causing fatal disease in humans and effecting great economical loss in the livestock industry. Results Through screening of hybridomas derived from mice immunized with γ-irradiated Nipah virus, we identified two secreted antibodies; one reactive with the nucleocapsid (N protein and the other, the phosphoprotein (P of henipaviruses. Epitope mapping and protein sequence alignments between NiV and HeV suggest the last 14 amino acids of the carboxyl terminus of the N protein is the target of the anti-N antibody. The anti-P antibody recognizes an epitope in the amino-terminal half of P protein. These monoclonal antibodies were used to develop two antigen capture ELISAs, one for virus detection and the other for differentiation between NiV and HeV. The lower limit of detection of the capture assay with both monoclonal antibodies was 400 pfu. The anti-N antibody was used to successfully detect NiV in a lung tissue suspension from an infected pig. Conclusion The antigen capture ELISA developed is potentially affordable tool to provide rapid detection and differentiation between the henipaviruses.

  12. Maximum-Entropy Models of Sequenced Immune Repertoires Predict Antigen-Antibody Affinity.

    Directory of Open Access Journals (Sweden)

    Lorenzo Asti

    2016-04-01

    Full Text Available The immune system has developed a number of distinct complex mechanisms to shape and control the antibody repertoire. One of these mechanisms, the affinity maturation process, works in an evolutionary-like fashion: after binding to a foreign molecule, the antibody-producing B-cells exhibit a high-frequency mutation rate in the genome region that codes for the antibody active site. Eventually, cells that produce antibodies with higher affinity for their cognate antigen are selected and clonally expanded. Here, we propose a new statistical approach based on maximum entropy modeling in which a scoring function related to the binding affinity of antibodies against a specific antigen is inferred from a sample of sequences of the immune repertoire of an individual. We use our inference strategy to infer a statistical model on a data set obtained by sequencing a fairly large portion of the immune repertoire of an HIV-1 infected patient. The Pearson correlation coefficient between our scoring function and the IC50 neutralization titer measured on 30 different antibodies of known sequence is as high as 0.77 (p-value 10-6, outperforming other sequence- and structure-based models.

  13. In vitro and in vivo properties of human/mouse chimeric monoclonal antibody specific for common acute lymphocytic leukemia antigen

    International Nuclear Information System (INIS)

    Saga, T.; Endo, K.; Koizumi, M.; Kawamura, Y.; Watanabe, Y.; Konishi, J.; Ueda, R.; Nishimura, Y.; Yokoyama, M.; Watanabe, T.

    1990-01-01

    A human/mouse chimeric monoclonal antibody specific for a common acute lymphocytic leukemia antigen was efficiently obtained by ligating human heavy-chain enhancer element to the chimeric heavy- and light-chain genes. Cell binding and competitive inhibition assays of both radioiodine and indium-111- (111In) labeled chimeric antibodies demonstrated in vitro immunoreactivity identical with that of the parental murine monoclonal antibodies. The biodistribution of the radiolabeled chimeric antibody in tumor-bearing nude mice was similar to that of the parental murine antibody. Tumor accumulation of radioiodinated parental and chimeric antibodies was lower than that of 111 In-labeled antibodies, probably because of dehalogenation of the radioiodinated antibodies. Indium-111-labeled chimeric antibody clearly visualized xenografted tumor. These results suggest that a human/mouse chimeric antibody can be labeled with 111 In and radioiodine without the loss of its immunoreactivity, and that chimeric antibody localizes in vivo in the same way as the parental murine antibody

  14. Studies of cytotoxic antibodies against eye muscle antigens in patients with thyroid-associated ophthalmopathy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Z.-G.; Hiromatsu, Y.; Salvi, M.; Triller, H.; Bernard, N.; Wall, J.R. (Thyroid Research Unit, The Montreal General Hospital Research Institute, Montreal, Quebec (Canada)); Medeiros-Neto, G.; Iacona, A.; Lima, N. (Thyroid Clinic, Hospital das Clinicas, Sao Paulo (Brazil))

    1989-01-01

    We have studied the prevalence and significance of cytotoxic antibodies against human eye muscle cells, as detected in antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-mediated antibody-dependent cytotoxicity (CMAC) in {sup 51}Cr release assays, in patients with Graves' ophthalmopathy or Hashimoto's thyroiditis. A high prevalence of positive ADCC tests was found in all groups of patients with ophthalmopathy tested. Tests were positive in 64% of patients with Graves' ophthalmopathy from an area of severe iodine deficiency (Sao Paulo) and in 64% of such patients from an iodine replete area (Montreal). In patients with so-called ''euthyroid ophthalmopathy'', i.e. eye disease associated with thyroiditis, ADCC tests were positive in 75 and 38% of patients from the two areas, respectively, while tests were positive in 40 and 22%, respectively, of patients with Graves' hyperthyroidism without evident eye disease. In normal subjects, levels of {sup 51}Cr release was always at background levels. In a group of patients from the high-iodine area, levels of antibodies in ADCC correlated positively with the intraocular pressure (mmHg) in primary position as a parameter of eye muscle dysfunction. In patients with ophthalmopathy, positive ADCC tests were assciated with antibodies to eye muscle membrane antigens of 55,65 and 95 kD as detected by immunoblotting, although the correlation was not close for any antigen. in contrast, CMAC tests were negative in all patients with ophthalmopathy. We also tested 9 mouse and 10 human monoclonal antibodies, reactive with orbital antigens in an enzyme-linked immunosorbent assay, for cytotoxic activity, in ADCC and CMAC, against eye muscle and thyroid cells. All monoclonal antibodies were of the IgM class and negative in ADCC assays. (Abstract Truncated)

  15. Determining the binding affinity of therapeutic monoclonal antibodies towards their native unpurified antigens in human serum.

    Directory of Open Access Journals (Sweden)

    Christine Bee

    Full Text Available Monoclonal antibodies (mAbs are a growing segment of therapeutics, yet their in vitro characterization remains challenging. While it is essential that a therapeutic mAb recognizes the native, physiologically occurring epitope, the generation and selection of mAbs often rely on the use of purified recombinant versions of the antigen that may display non-native epitopes. Here, we present a method to measure both, the binding affinity of a therapeutic mAb towards its native unpurified antigen in human serum, and the antigen's endogenous concentration, by combining the kinetic exclusion assay and Biacore's calibration free concentration analysis. To illustrate the broad utility of our method, we studied a panel of mAbs raised against three disparate soluble antigens that are abundant in the serum of healthy donors: proprotein convertase subtilisin/kexin type 9 (PCSK9, progranulin (PGRN, and fatty acid binding protein (FABP4. We also determined the affinity of each mAb towards its purified recombinant antigen and assessed whether the interactions were pH-dependent. Of the six mAbs studied, three did not appear to discriminate between the serum and recombinant forms of the antigen; one mAb bound serum antigen with a higher affinity than recombinant antigen; and two mAbs displayed a different affinity for serum antigen that could be explained by a pH-dependent interaction. Our results highlight the importance of taking pH into account when measuring the affinities of mAbs towards their serum antigens, since the pH of serum samples becomes increasingly alkaline upon aerobic handling.

  16. Antibodies to a common outer envelope antigen of Treponema hyodysenteriae with antibacterial activity.

    Science.gov (United States)

    Sellwood, R; Kent, K A; Burrows, M R; Lysons, R J; Bland, A P

    1989-08-01

    Outer envelopes of Treponema hyodysenteriae strains P18A and VS1 were prepared and characterized by SDS-PAGE. In Western blot analysis of eleven strains of T. hyodysenteriae and two intestinal non-pathogenic spirochaetes, polyclonal antiserum raised to the outer envelopes of strain P18A contained antibodies primarily to two polypeptides. A 45 kDa polypeptide was present in only two strains of T. hyodysenteriae, P18A and MC52/80, whereas another antigen of 16 kDa was common to all eleven strains of T. hyodysenteriae but was not present in the two nonpathogens. Immunogold labelling of whole organisms suggested that the 16 kDa antigen was present on the surface of the spirochaetes. In in vitro tests the serum agglutinated and inhibited growth of only the T. hyodysenteriae strains, suggesting that antibodies to the 16 kDa antigen were responsible for these activities. Serum from a gnotobiotic pig infected with T. hyodysenteriae strain P18A had antibodies to the 16 kDa antigen alone and also possessed agglutinating and growth-inhibitory activities.

  17. The natural antibody repertoire of sharks and humans recognizes the potential universe of antigens.

    Science.gov (United States)

    Adelman, Miranda K; Schluter, Samuel F; Marchalonis, John J

    2004-02-01

    In ancestral sharks, a rapid emergence in the evolution of the immune system occurred, giving jawed-vertebrates the necessary components for the combinatorial immune response (CIR). To compare the natural antibody (NAb) repertoires of the most divergent vertebrates with the capacity to produce antibodies, we isolated NAbs to the same set of antigens by affinity chromatography from two species of Carcharhine sharks and from human polyclonal IgG and IgM antibody preparations. The activities of the affinity-purified anti-T-cell receptor (anti-TCR) NAbs were compared with those of monoclonal anti-TCR NAbs that were generated from a systemic lupus erythematosus patient. We report that sharks and humans, representing the evolutionary extremes of vertebrate species sharing the CIR, have NAbs to human TCRs, Igs, the human senescent cell antigen, and to numerous retroviral antigens, indicating that essential features of the combinatorial repertoire and the capacity to recognize the potential universe of antigens is shared among all jawed-vertebrates.

  18. Anti-soluble liver antigen (SLA) antibodies in chronic HCV infection.

    Science.gov (United States)

    Vitozzi, Susana; Lapierre, Pascal; Djilali-Saiah, Idriss; Marceau, Gabriel; Beland, Kathie; Alvarez, Fernando

    2004-05-01

    Hepatitis C infection is associated with autoimmune disorders, such as the production of autoantibodies. Anti-LKM1 and anti-LC1, immunomarkers of type 2 autoimmune hepatitis, have been previously associated with a HCV infection. Anti-Soluble-Liver-Antigen autoantibodies (SLA) are specifically associated with type 1 and type 2 autoimmune hepatitis and more closely related to patients who relapse after steroid therapy. The recent molecular cloning of the soluble liver antigen provides the opportunity to develop more specific tests for the detection of antibodies against it. The aim of this work is to characterize anti-soluble-liver autoantibodies in sera from patients chronically infected by HCV. A recombinant cDNA from activated Jurkat cells coding for the full length tRNP(Ser)Sec/SLA antigen was obtained. ELISA, Western Blot and immunoprecipitation tests were developed and used to search for linear and conformational epitopes recognized by anti-SLA antibodies in sera from patients chronically infected by HCV. Anti-soluble liver antigen antibodies were found in sera from 10.4% of HCV-infected patients. The prevalence was significantly increased to 27% when anti-LKM1 was also present. Most anti-SLA reactivity was directed against conformational epitopes on the antigen. The means titers by ELISA were lower than those obtained in type 2 AIH. The result of autoantibody isotyping showed a subclass restriction to IgG1 and also IgG4. This study shows the presence of anti-SLA antibodies in approximately 10% of HCV infected patients. The prevalence of SLA autoantibodies in HCV infected patients increases when LKM1 autoantibodies are also present. The relationship between the prevalence of this characteristic autoimmune hepatitis autoantibody and the implication of an autoimmune phenomenon in the liver injury of patients chronically infected by HCV needs further investigation.

  19. Anti-human neutrophil antigen-1a, -1b, and -2 antibodies in neonates and children with immune neutropenias analyzed by extracted granulocyte antigen immunofluorescence assay.

    Science.gov (United States)

    Onodera, Rie; Kurita, Emi; Taniguchi, Kikuyo; Karakawa, Shuhei; Okada, Satoshi; Kihara, Hirotaka; Fujii, Teruhisa; Kobayashi, Masao

    2017-11-01

    Anti-human neutrophil antigen (HNA) antibodies have been implicated in the development of neonatal alloimmune neutropenia (NAN) and autoimmune neutropenia (AIN). There are many conventional assay methods that detect anti-HNA antibodies. However, a method to measure multiple samples and detect several anti-HNA antibodies simultaneously is needed. We developed a new method, the extracted granulocyte antigen immunofluorescence assay (EGIFA), to analyze anti-HNA-1a, -1b, and -2 antibodies in sera. The results obtained by EGIFA were evaluated in comparison with those from several standard assay methods. Anti-HNA antibodies in serum samples from nine familial cases with suspected NAN (n = 19) and children with suspected AIN (n = 88) were also measured by EGIFA. The evaluation of nine serum samples with anti-HNA antibodies suggested that EGIFA demonstrated equivalent specificity and superior sensitivity to monoclonal antibody-specific immobilization of granulocyte antigens and had comparable sensitivity to the granulocyte indirect immunofluorescence test. EGIFA successfully detected anti-HNA-1a or -1b antibodies in seven of nine familial cases with suspected NAN. EGIFA detected anti-HNA antibodies in 40.9% of children with suspected AIN. Among them, isolated anti-HNA-1a or -1b antibody was detected in 4.5 or 12.5% of children, respectively, and anti-HNA-2 antibody was identified in 3.4% of children. The 30.8% (16 of 52) of children negative for anti-HNA antibody by EGIFA were positive for anti-HLA antibody. EGIFA facilitated the measurement of anti-HNA-1a, -1b, and/or -2 antibodies in sera. The prompt measurement of anti-HNA antibodies will improve the diagnosis and clinical management of patients with suspected NAN or AIN. © 2017 AABB.

  20. antigen from irradiated Trypanosoma evansi and its correlation with antibody forming

    International Nuclear Information System (INIS)

    Sadi, Suharni; Arifin, Muchson

    1998-01-01

    In this research parasites of T. evansi was weakened by gamma irradiation dose of 300 Gy. This antigen being before being used was coupled/bounded with a carrier (Freund's adjuvant). West star rats of 3 months old were as used as treated animal. These animal were divided into 4 groups contained 5 rats. Group I (Control) was untreated animals, Group II (radiation) the animals were irradiated with a low dose 0.5 Gy. Group III Immunization) the animals were immunized with irradiated antigen, and Group IV (Immunization and radiation) the animal were immunized and then irradiated with a low dose of 0.5 Gy. Immunization were done by intraperitoneal route with irradiated antigen (0.5-1ml). These results were as follows : the polyclonal antibody forming of Group I (control), Group II (Radiation), Group III (Immunization), and Group IV (Immunization and radiation) were 6.34; 5.96; and 5.88 mg/ml, respectively. Group III (Immunization) Yielded polyclonal antibody a little higher than the other treated animals. Even though the antigen was coupled with a carrier, it seemed that it did not influence the parasites variant antigenic types (VTA). (author)

  1. 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.)

  2. 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.)

  3. Identification of a surface antigen on Theileria parva sporozoites by monoclonal antibody.

    OpenAIRE

    Dobbelaere, D A; Shapiro, S Z; Webster, P

    1985-01-01

    A mouse monoclonal antibody (mAbD1) that neutralizes sporozoites of different stocks of the protozoan parasite Theileria parva has been used to localize and identify a sporozoite antigen. Protein A-colloidal gold was used to localize bound mAbD1 in immunoelectron microscopic studies. mAbD1 bound to sporozoite antigen, which was evenly spread over the surface of all sporozoites. Immune complexes were obtained by incubation of sporozoite suspensions with mAbD1 followed by Zwittergent 3-14 extra...

  4. Cell membrane antigen-antibody complex dissociation by the widely used glycine-HCL method: an unreliable procedure for studying antibody internalization.

    Science.gov (United States)

    Tsaltas, G; Ford, C H

    1993-02-01

    Methods following the process of binding and internalization of antibodies to cell surface antigens have often employed low pH isoosmolar buffers in order to dissociate surface antigen-antibody complexes. One of the most widely used buffers is a 0.05 M glycine-HCL buffer pH 2.8. Since the efficacy of action of this buffer was critical to a series of internalization experiments employing monoclonal antibodies (Mabs) to carcinoembryonic antigen (CEA) expressing cancer cell lines in this laboratory, we tested its performance in a number of different assays. Our results indicate that this buffer only partially dissociates antigen-antibody bonds and therefore can introduce major inaccuracies in internalization experiments.

  5. Anti-Chol-1 antigen, GQ1bα, antibodies are associated with Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Toshio Ariga

    Full Text Available The interaction of amyloid β-proteins (Aβ with membrane gangliosides has been reported to be an early event in Aβ fibril formation in Alzheimer's disease (AD. Neuronal degeneration in AD has been postulated to be associated with the presence of anti-ganglioside antibodies in patient sera. Using an enzyme-linked immunosorbent assay (ELISA and high-performance thin-layer chromatography (HPTLC immunostaining, sera from 27 individuals (10 with AD, 6 with vascular dementia (VD, and 11 non-demented age-matched pathological controls were examined in order to detect anti-glycosphingolipid (GSL antibodies, including anti-cholinergic-specific antigen (Chol-1α; GQ1bα antibodies. All sera had natural antibodies against ganglio-N-tetraosyl gangliosides (brain-type gangliosides. However, sera of demented patients with AD and VD had significantly higher titers of anti-GSL antibodies than those in age-matched pathological controls. Although most serum antibodies, including anti- GM1, -GT1b, -GQ1b, -GQ1bα, were of the IgM type, the presence of the IgG type antibodies was also significantly elevated in the sera of demented patients with AD. Anti-GT1b antibodies of the IgG type were elevated in AD (90%, 9 of 10 cases and VD (100%, respectively. Most surprisingly, anti-GQ1bα antibodies (IgM were found in 90% (9/10 and 100% (6/6 in the sera of patients with AD and VD, respectively. Since GQ1bα is present in the cerebral cortex and hippocampus, the presence of anti-GQ1bα antibodies may play an important role in disrupting cholinergic synaptic transmission and may participate in the pathogenesis of dementia. We conclude that elevated anti-GSL antibody titers may be useful as an aid for clinical diagnosis of those dementias.

  6. Studies of cytotoxic antibodies against eye muscle antigens in patients with thyroid-associated ophthalmopathy

    International Nuclear Information System (INIS)

    Zhang, Z.-G.; Hiromatsu, Y.; Salvi, M.; Triller, H.; Bernard, N.; Wall, J.R.; Medeiros-Neto, G.; Iacona, A.; Lima, N.

    1989-01-01

    We have studied the prevalence and significance of cytotoxic antibodies against human eye muscle cells, as detected in antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-mediated antibody-dependent cytotoxicity (CMAC) in 51 Cr release assays, in patients with Graves' ophthalmopathy or Hashimoto's thyroiditis. A high prevalence of positive ADCC tests was found in all groups of patients with ophthalmopathy tested. Tests were positive in 64% of patients with Graves' ophthalmopathy from an area of severe iodine deficiency (Sao Paulo) and in 64% of such patients from an iodine replete area (Montreal). In patients with so-called ''euthyroid ophthalmopathy'', i.e. eye disease associated with thyroiditis, ADCC tests were positive in 75 and 38% of patients from the two areas, respectively, while tests were positive in 40 and 22%, respectively, of patients with Graves' hyperthyroidism without evident eye disease. In normal subjects, levels of 51 Cr release was always at background levels. In a group of patients from the high-iodine area, levels of antibodies in ADCC correlated positively with the intraocular pressure (mmHg) in primary position as a parameter of eye muscle dysfunction. In patients with ophthalmopathy, positive ADCC tests were assciated with antibodies to eye muscle membrane antigens of 55,65 and 95 kD as detected by immunoblotting, although the correlation was not close for any antigen. in contrast, CMAC tests were negative in all patients with ophthalmopathy. We also tested 9 mouse and 10 human monoclonal antibodies, reactive with orbital antigens in an enzyme-linked immunosorbent assay, for cytotoxic activity, in ADCC and CMAC, against eye muscle and thyroid cells. All monoclonal antibodies were of the IgM class and negative in ADCC assays. When tested in CMAC against eye muscle cells, one of 9 mouse and 5 of 8 human monoclonal antibodies showed significant activity while tests were positive in one of 9 and one of 10 monoclonal antibodies

  7. Variable Domain N-Linked Glycans Acquired During Antigen-Specific Immune Responses Can Contribute to Immunoglobulin G Antibody Stability

    Directory of Open Access Journals (Sweden)

    Fleur S. van de Bovenkamp

    2018-04-01

    Full Text Available Immunoglobulin G (IgG can contain N-linked glycans in the variable domains, the so-called Fab glycans, in addition to the Fc glycans in the CH2 domains. These Fab glycans are acquired following introduction of N-glycosylation sites during somatic hypermutation and contribute to antibody diversification. We investigated whether Fab glycans may—in addition to affecting antigen binding—contribute to antibody stability. By analyzing thermal unfolding profiles of antibodies with or without Fab glycans, we demonstrate that introduction of Fab glycans can improve antibody stability. Strikingly, removal of Fab glycans naturally acquired during antigen-specific immune responses can deteriorate antibody stability, suggesting in vivo selection of stable, glycosylated antibodies. Collectively, our data show that variable domain N-linked glycans acquired during somatic hypermutation can contribute to IgG antibody stability. These findings indicate that introducing Fab glycans may represent a mechanism to improve therapeutic/diagnostic antibody stability.

  8. Vaxfectin enhances antigen specific antibody titers and maintains Th1 type immune responses to plasmid DNA immunization.

    Science.gov (United States)

    Reyes, L; Hartikka, J; Bozoukova, V; Sukhu, L; Nishioka, W; Singh, G; Ferrari, M; Enas, J; Wheeler, C J; Manthorpe, M; Wloch, M K

    2001-06-14

    Antigen specific immune responses were characterized after intramuscular immunization of BALB/c mice with 5 antigen encoding plasmid DNAs (pDNAs) complexed with Vaxfectin, a cationic lipid formulation. Vaxfectin increased IgG titers for all of the antigens with no effect on the CTL responses to the 2 antigens for which CTL assays were performed. Both antigen specific IgG1 and IgG2a were increased, although IgG2a remained greater than IgG1. Furthermore, Vaxfectin had no effect on IFN-gamma or IL-4 production by splenocytes re-stimulated with antigen, suggesting that the Th1 type responses typical of intramuscular pDNA immunization were not altered. Studies with IL-6 -/- mice suggest that the antibody enhancement is IL-6 dependent and results in a correlative increase in antigen specific antibody secreting cells.

  9. Characterisation of monoclonal antibodies for human luteinising hormone, and mapping of antigenic determinants on the hormone

    International Nuclear Information System (INIS)

    Soos, M.; Siddle, K.

    1983-01-01

    Twelve mouse monoclonal antibodies for human luteinising hormone were produced. The affinities varied from 4 X 10 7 to 1 X 10 10 l/mol. The specificity of each antibody was assessed by determining the relative reactivities with luteinising hormone, thyroid stimulating hormone, follicle stimulating hormone and chorionic gonadotrophin. Six antibodies bound to the α-subunit as shown by similar reactivity with all hormones, and the remainder to the β-subunit as shown by specificity for luteinising hormone. This latter group of antibodies cross-reacted only weakly with thyroid stimulating hormone (approximately 10%) and follicle stimulating hormone (approximately 3%). Three of these antibodies also showed low reactivity towards chorionic gonadotrophin (<10%), though the others did not (80-300%). The ability of different antibodies to bind simultaneously to luteinising hormone was examined and it was shown that several distinct antigenic determinants existed on both subunits. The characterisation of monoclonal binding sites is discussed in relation to the use of antibodies in two-site immunoradiometric assays. (Auth.)

  10. Ta1, a novel 105 KD human T cell activation antigen defined by a monoclonal antibody.

    Science.gov (United States)

    Fox, D A; Hussey, R E; Fitzgerald, K A; Acuto, O; Poole, C; Palley, L; Daley, J F; Schlossman, S F; Reinherz, E L

    1984-09-01

    By using a murine monoclonal antibody produced against an IL 2-dependent human T cell line, we defined a T lineage-specific molecule, termed Ta1, that is expressed strongly on activated T lymphocytes of both the T4 and T8 subsets, as well as on T cell lines and clones, but only weakly on a fraction of resting T cells. SDS-PAGE analysis of immunoprecipitates from 125I-labeled, activated T cells demonstrates a single major band of apparent m.w. 105 KD under both reducing and nonreducing conditions. Unlike anti-IL 2 receptor antibodies, anti-Ta1 does not inhibit T cell proliferative responses to mitogen, antigen, or IL 2-containing medium. Moreover, anti-Ta1 has no effect on T cell-mediated cytotoxicity. Ta1 appears to be a novel human T cell-specific activation antigen that may serve as a useful marker of T cell activation in human disease.

  11. Heritability of antibody isotype and subclass responses to Plasmodium falciparum antigens.

    Directory of Open Access Journals (Sweden)

    Nancy O Duah

    2009-10-01

    Full Text Available It is important to understand the extent to which genetic factors regulate acquired immunity to common infections. A classical twin study design is useful to estimate the heritable component of variation in measurable immune parameters.This study assessed the relative heritability of different plasma antibody isotypes and subclasses (IgG1, IgG2, IgG3, IgG4, IgM, IgA and IgE naturally acquired to P. falciparum blood stage antigens AMA1, MSP1-19, MSP2 (two allelic types and MSP3 (two allelic types. Separate analyses were performed on plasma from 213 pairs of Gambian adult twins, 199 child twin pairs sampled in a dry season when there was little malaria transmission, and another set of 107 child twin pairs sampled at the end of the annual wet season when malaria was common. There were significantly positive heritability (h(2 estimates for 48% (20/42 of the specific antibody assays (for the seven isotypes and subclasses to the six antigens tested among the adults, 48% (20/42 among the children in the dry season and 31% (13/42 among the children in the wet season. In children, there were significant heritability estimates for IgG4 reactivity against each of the antigens, and this subclass had higher heritability than the other subclasses and isotypes. In adults, 75% (15/20 of the significantly heritable antigen-specific isotype responses were attributable to non-HLA class II genetic variation, whereas none showed a significant HLA contribution.Genome-wide approaches are now warranted to map the major genetic determinants of variable antibody isotype and subclass responses to malaria, alongside evaluation of their impact on infection and disease. Although plasma levels of IgG4 to malaria antigens are generally low, the exceptionally high heritability of levels of this subclass in children deserves particular investigation.

  12. Means for use in radioimmunodetection of an antigen-antibody reaction

    International Nuclear Information System (INIS)

    Reynolds, J.H.

    1983-01-01

    A unitized, solid phase kit for radioimmunoassay is described. All of the necessary assay reagents are incorporated in a single tube. Requiring only the addition of the patient's sample, all phases of the assay procedure are performed in this tube. Antibodies are bound to the tube surface, while labelled antigens are also present but unbound. Storage in the absence of air and water results in the stabilization of the reagents such that the system can be stored for long periods

  13. 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.

  14. 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,...

  15. Extracellular Expression in Aspergillus niger of an Antibody Fused to Leishmania sp. Antigens.

    Science.gov (United States)

    Magaña-Ortíz, Denis; Fernández, Francisco; Loske, Achim M; Gómez-Lim, Miguel A

    2018-01-01

    Nucleoside hydrolase and sterol 24-c-methyltransferase, two antigenic proteins of Leishmania sp., were expressed in Aspergillus niger. Genetic transformation of conidia was achieved using underwater shock waves. scFv antibody addressed to DEC205, a receptor of dendritic cells, was fused to two proteins of Leishmania sp. Receptor 205 has a relevant role in the immune system in mammals; it can modulate T cell response to different antigens. Extracellular expression strategy of recombinant antibody was achieved using a fragment of native glucoamylase A (514 aa) as a carrier. Fermentations in shake flasks showed that the recombinant protein (104 kDa) was expressed and secreted only when maltose was used as carbon source; on the contrary, the expression was highly repressed in presence of xylose. Noteworthy, recombinant protein was secreted without glucoamylase-carrier and accumulation at intracellular level was not observed. The results presented here demonstrate the high value of Aspergillus niger as biotechnological platform for recombinant antibodies against Leishmania sp. at low cost. To the best of our knowledge, this is the first report about the recombinant expression of antigenic proteins of Leishmania sp. in filamentous fungi. The protein obtained can be used to explore novel strategies to induce immunity against Leishmania sp. or it can be employed in diagnostic kits to detect this neglected disease.

  16. Shark Variable New Antigen Receptor (VNAR Single Domain Antibody Fragments: Stability and Diagnostic Applications

    Directory of Open Access Journals (Sweden)

    Stewart Nuttall

    2013-01-01

    Full Text Available The single variable new antigen receptor domain antibody fragments (VNARs derived from shark immunoglobulin new antigen receptor antibodies (IgNARs represent some of the smallest known immunoglobulin-based protein scaffolds. As single domains, they demonstrate favorable size and cryptic epitope recognition properties, making them attractive in diagnosis and therapy of numerous disease states. Here, we examine the stability of VNAR domains with a focus on a family of VNARs specific for apical membrane antigen 1 (AMA-1 from Plasmodium falciparum. The VNARs are compared to traditional monoclonal antibodies (mAbs in liquid, lyophilized and immobilized nitrocellulose formats. When maintained in various formats at 45 °C, VNARs have improved stability compared to mAbs for periods of up to four weeks. Using circular dichroism spectroscopy we demonstrate that VNAR domains are able to refold following heating to 80 °C. We also demonstrate that VNAR domains are stable during incubation under potential in vivo conditions such as stomach acid, but not to the protease rich environment of murine stomach scrapings. Taken together, our results demonstrate the suitability of shark VNAR domains for various diagnostic platforms and related applications.

  17. 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.)

  18. Greek rheumatoid arthritis patients have elevated levels of antibodies against antigens from Proteus mirabilis.

    Science.gov (United States)

    Christopoulos, Georgios; Christopoulou, V; Routsias, J G; Babionitakis, A; Antoniadis, C; Vaiopoulos, G

    2017-03-01

    Patients with rheumatoid arthritis (RA) from different ethnic groups present elevated levels of antibodies against Proteus mirabilis. This finding implicates P. mirabilis in the development of RA. The aim of this study was to investigate the importance of P. mirabilis in the etiopathogenesis of RA in Greek RA patients. In this study, 63 patients with RA and 38 healthy controls were included. Class-specific antibodies IgM, IgG, and IgA against three human cross-reactive and non-cross-reactive synthetic peptides from P. mirabilis-hemolysin (HpmB), urease C (UreC), and urease F (UreF)-were performed in all subjects, using the ELISA method. RA patients had elevated levels of IgM, IgG, and IgA antibodies against HpmB and UreC Proteus peptide which are significantly different compared to healthy controls: p = 0.005, p Proteus peptide-which are non-cross-reactive with human tissue antigens-were observed and their significant difference compared to healthy controls (p = 0.007, p mirabilis antigenic epitopes, such as in North European populations, albeit Greek RA patients presenting the cross-reaction antigen in a low percentage. These results indicate that P. mirabilis through the molecular mimicry mechanism leads to inflammation and damage of the joints in RA.

  19. Optimizing Production of Antigens and Fabs in the Context of Generating Recombinant Antibodies to Human Proteins.

    Directory of Open Access Journals (Sweden)

    Nan Zhong

    Full Text Available We developed and optimized a high-throughput project workflow to generate renewable recombinant antibodies to human proteins involved in epigenetic signalling. Three different strategies to produce phage display compatible protein antigens in bacterial systems were compared, and we found that in vivo biotinylation through the use of an Avi tag was the most productive method. Phage display selections were performed on 265 in vivo biotinylated antigen domains. High-affinity Fabs (<20nM were obtained for 196. We constructed and optimized a new expression vector to produce in vivo biotinylated Fabs in E. coli. This increased average yields up to 10-fold, with an average yield of 4 mg/L. For 118 antigens, we identified Fabs that could immunoprecipitate their full-length endogenous targets from mammalian cell lysates. One Fab for each antigen was converted to a recombinant IgG and produced in mammalian cells, with an average yield of 15 mg/L. In summary, we have optimized each step of the pipeline to produce recombinant antibodies, significantly increasing both efficiency and yield, and also showed that these Fabs and IgGs can be generally useful for chromatin immunoprecipitation (ChIP protocols.

  20. 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.

  1. Evaluation of the impact of a control program against taeniasis-cysticercosis (Taenia solium.

    Directory of Open Access Journals (Sweden)

    Aline S de Aluja

    2014-05-01

    Full Text Available Objetive. The impact of a control program is evaluated to eventually eradicate taeniasis-cysticercosis (Taenia solium based on education and vaccination of pigs. Materials and methods. The prevalence of porcine cysticercosis was estimated using tongue inspection, ultrasound and determination of antibodies, before and three years after the application in three regions of the state of Guerrero. Results. A significant reduction in the prevalence of porcine cysticercosis of 7 to 0.5% and 3.6 to 0.3% estimated by tongue examination or ultrasound respectively (p menor que 0.01 and a no significant decrease in seroprevalence from 17.7 to 13.3% were observed. Conclusions. The reduction of the prevalence of taeniasis-cysticercosis establishes the program’s effectiveness in preventing infection. The sustained presence of antibodies, compatible with contact of Taenia solium or other related helminths, underlines the importance of maintaining interventionsto achieve eradication.

  2. [Evaluation of the impact of a control program against taeniasis-cysticercosis (Taenia solium)].

    Science.gov (United States)

    de Aluja, Aline S; Suárez-Marín, Raúl; Sciutto-Conde, Edda; Morales-Soto, Julio; Martínez-Maya, José Juan; Villalobos, Nelly

    2014-01-01

    The impact of a control program is evaluated to eventually eradicate taeniasis-cysticercosis (Taenia solium) based on education and vaccination of pigs. The prevalence of porcine cysticercosis was estimated using tongue inspection, ultrasound and determination of antibodies, before and three years after the application in three regions of the state of Guerrero. A significant reduction in the prevalence of porcine cysticercosis of 7 to 0.5% and 3.6 to 0.3% estimated by tongue examination or ultrasound respectively (ptaeniasis-cysticercosis establishes the program's effectiveness in preventing infection. The sustained presence of antibodies, compatible with contact of Taenia solium or other related helminths, underlines the importance of maintaining interventions to achieve eradication.

  3. Tumour auto-antibody screening: performance of protein microarrays using SEREX derived antigens

    International Nuclear Information System (INIS)

    Stempfer, René; Weinhäusel, Andreas; Syed, Parvez; Vierlinger, Klemens; Pichler, Rudolf; Meese, Eckart; Leidinger, Petra; Ludwig, Nicole; Kriegner, Albert; Nöhammer, Christa

    2010-01-01

    The simplicity and potential of minimal invasive testing using serum from patients make auto-antibody based biomarkers a very promising tool for use in diagnostics of cancer and auto-immune disease. Although several methods exist for elucidating candidate-protein markers, immobilizing these onto membranes and generating so called macroarrays is of limited use for marker validation. Especially when several hundred samples have to be analysed, microarrays could serve as a good alternative since processing macro membranes is cumbersome and reproducibility of results is moderate. Candidate markers identified by SEREX (serological identification of antigens by recombinant expression cloning) screenings of brain and lung tumour were used for macroarray and microarray production. For microarray production recombinant proteins were expressed in E. coli by autoinduction and purified His-tag (histidine-tagged) proteins were then used for the production of protein microarrays. Protein arrays were hybridized with the serum samples from brain and lung tumour patients. Methods for the generation of microarrays were successfully established when using antigens derived from membrane-based selection. Signal patterns obtained by microarrays analysis of brain and lung tumour patients' sera were highly reproducible (R = 0.92-0.96). This provides the technical foundation for diagnostic applications on the basis of auto-antibody patterns. In this limited test set, the assay provided high reproducibility and a broad dynamic range to classify all brain and lung samples correctly. Protein microarray is an efficient means for auto-antibody-based detection when using SEREX-derived clones expressing antigenic proteins. Protein microarrays are preferred to macroarrays due to the easier handling and the high reproducibility of auto-antibody testing. Especially when using only a few microliters of patient samples protein microarrays are ideally suited for validation of auto-antibody

  4. OptMAVEn--a new framework for the de novo design of antibody variable region models targeting specific antigen epitopes.

    Directory of Open Access Journals (Sweden)

    Tong Li

    Full Text Available Antibody-based therapeutics provides novel and efficacious treatments for a number of diseases. Traditional experimental approaches for designing therapeutic antibodies rely on raising antibodies against a target antigen in an immunized animal or directed evolution of antibodies with low affinity for the desired antigen. However, these methods remain time consuming, cannot target a specific epitope and do not lead to broad design principles informing other studies. Computational design methods can overcome some of these limitations by using biophysics models to rationally select antibody parts that maximize affinity for a target antigen epitope. This has been addressed to some extend by OptCDR for the design of complementary determining regions. Here, we extend this earlier contribution by addressing the de novo design of a model of the entire antibody variable region against a given antigen epitope while safeguarding for immunogenicity (Optimal Method for Antibody Variable region Engineering, OptMAVEn. OptMAVEn simulates in silico the in vivo steps of antibody generation and evolution, and is capable of capturing the critical structural features responsible for affinity maturation of antibodies. In addition, a humanization procedure was developed and incorporated into OptMAVEn to minimize the potential immunogenicity of the designed antibody models. As case studies, OptMAVEn was applied to design models of neutralizing antibodies targeting influenza hemagglutinin and HIV gp120. For both HA and gp120, novel computational antibody models with numerous interactions with their target epitopes were generated. The observed rates of mutations and types of amino acid changes during in silico affinity maturation are consistent with what has been observed during in vivo affinity maturation. The results demonstrate that OptMAVEn can efficiently generate diverse computational antibody models with both optimized binding affinity to antigens and reduced

  5. Spatial clustering of porcine cysticercosis in Mbulu district, northern Tanzania.

    Directory of Open Access Journals (Sweden)

    Helena A Ngowi

    Full Text Available BACKGROUND: Porcine cysticercosis is caused by a zoonotic tapeworm, Taenia solium, which causes serious disease syndromes in human. Effective control of the parasite requires knowledge on the burden and pattern of the infections in order to properly direct limited resources. The objective of this study was to establish the spatial distribution of porcine cysticercosis in Mbulu district, northern Tanzania, to guide control strategies. METHODOLOGY/PRINCIPAL FINDINGS: This study is a secondary analysis of data collected during the baseline and follow-up periods of a randomized community trial aiming at reducing the incidence rate of porcine cysticercosis through an educational program. At baseline, 784 randomly selected pig-keeping households located in 42 villages in 14 wards were included. Lingual examination of indigenous pigs aged 2-12 (median 8 months, one randomly selected from each household, were conducted. Data from the control group of the randomized trial that included 21 of the 42 villages were used for the incidence study. A total of 295 pig-keeping households were provided with sentinel pigs (one each and reassessed for cysticercosis incidence once or twice for 2-9 (median 4 months using lingual examination and antigen ELISA. Prevalence of porcine cysticercosis was computed in Epi Info 3.5. The prevalence and incidence of porcine cysticercosis were mapped at household level using ArcView 3.2. K functions were computed in R software to assess general clustering of porcine cysticercosis. Spatial scan statistics were computed in SatScan to identify local clusters of the infection. The overall prevalence of porcine cysticercosis was 7.3% (95% CI: 5.6, 9.4; n = 784. The K functions revealed a significant overall clustering of porcine cysticercosis incidence for all distances between 600 m and 5 km from a randomly chosen case household based on Ag-ELISA. Lingual examination revealed clustering from 650 m to 6 km and between 7.5 and 10 km

  6. Taenia solium Human Cysticercosis: A Systematic Review of Sero-epidemiological Data from Endemic Zones around the World.

    Science.gov (United States)

    Coral-Almeida, Marco; Gabriël, Sarah; Abatih, Emmanuel Nji; Praet, Nicolas; Benitez, Washington; Dorny, Pierre

    2015-01-01

    Taenia solium cysticercosis is a zoonotic neglected disease responsible for severe health disorders such as seizures and death. Understanding the epidemiology of human cysticercosis (HCC) in endemic regions will help to expose critical information about the transmission of the disease, which could be used to design efficient control programs. This review gathered serological data on apparent prevalence of T. solium circulating antigens and/or seroprevalence of T. solium antibodies, apparent prevalence of human taeniasis and risk factors for HCC from endemic communities in order to understand the differences in exposure to the parasite and active infections with T. solium metacestodes in endemic areas around the world. Three databases were used to search sero-epidemiological data from community-based studies conducted between 1989 and 2014 in cysticercosis endemic communities worldwide. The search focused on data obtained from T. solium circulating antigen detection by monoclonal antibody-based sandwich ELISA and/or T. solium antibody seroprevalence determined by Enzyme-linked Immunoelectrotransfer Blot (EITB). A meta-analysis was performed per continent. A total of 39,271 participants from 19 countries, described in 37 articles were studied. The estimates for the prevalence of circulating T. solium antigens for Africa, Latin America and Asia were: 7.30% (95% CI [4.23-12.31]), 4.08% (95% CI [2.77-5.95]) and 3.98% (95% CI [2.81-5.61]), respectively. Seroprevalence estimates of T. solium antibodies were 17.37% (95% CI [3.33-56.20]), 13.03% (95% CI [9.95-16.88]) and 15.68% (95% CI [10.25-23.24]) respectively. Taeniasis reported prevalences ranged from 0 (95% CI [0.00-1.62]) to 17.25% (95% CI [14.55-20.23]). A significant variation in the sero-epidemiological data was observed within each continent, with African countries reporting the highest apparent prevalences of active infections. Intrinsic factors in the human host such as age and immunity were main determinants

  7. Taenia solium Human Cysticercosis: A Systematic Review of Sero-epidemiological Data from Endemic Zones around the World.

    Directory of Open Access Journals (Sweden)

    Marco Coral-Almeida

    Full Text Available Taenia solium cysticercosis is a zoonotic neglected disease responsible for severe health disorders such as seizures and death. Understanding the epidemiology of human cysticercosis (HCC in endemic regions will help to expose critical information about the transmission of the disease, which could be used to design efficient control programs. This review gathered serological data on apparent prevalence of T. solium circulating antigens and/or seroprevalence of T. solium antibodies, apparent prevalence of human taeniasis and risk factors for HCC from endemic communities in order to understand the differences in exposure to the parasite and active infections with T. solium metacestodes in endemic areas around the world.Three databases were used to search sero-epidemiological data from community-based studies conducted between 1989 and 2014 in cysticercosis endemic communities worldwide. The search focused on data obtained from T. solium circulating antigen detection by monoclonal antibody-based sandwich ELISA and/or T. solium antibody seroprevalence determined by Enzyme-linked Immunoelectrotransfer Blot (EITB. A meta-analysis was performed per continent.A total of 39,271 participants from 19 countries, described in 37 articles were studied. The estimates for the prevalence of circulating T. solium antigens for Africa, Latin America and Asia were: 7.30% (95% CI [4.23-12.31], 4.08% (95% CI [2.77-5.95] and 3.98% (95% CI [2.81-5.61], respectively. Seroprevalence estimates of T. solium antibodies were 17.37% (95% CI [3.33-56.20], 13.03% (95% CI [9.95-16.88] and 15.68% (95% CI [10.25-23.24] respectively. Taeniasis reported prevalences ranged from 0 (95% CI [0.00-1.62] to 17.25% (95% CI [14.55-20.23].A significant variation in the sero-epidemiological data was observed within each continent, with African countries reporting the highest apparent prevalences of active infections. Intrinsic factors in the human host such as age and immunity were main

  8. 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

  9. Native Mass Spectrometry, Ion mobility, and Collision-Induced Unfolding Categorize Malaria Antigen/Antibody Binding

    Science.gov (United States)

    Huang, Yining; Salinas, Nichole D.; Chen, Edwin; Tolia, Niraj H.; Gross, Michael L.

    2017-09-01

    Plasmodium vivax Duffy Binding Protein (PvDBP) is a promising vaccine candidate for P. vivax malaria. Recently, we reported the epitopes on PvDBP region II (PvDBP-II) for three inhibitory monoclonal antibodies (2D10, 2H2, and 2C6). In this communication, we describe the combination of native mass spectrometry and ion mobility (IM) with collision induced unfolding (CIU) to study the conformation and stabilities of three malarial antigen-antibody complexes. These complexes, when collisionally activated, undergo conformational changes that depend on the location of the epitope. CIU patterns for PvDBP-II in complex with antibody 2D10 and 2H2 are highly similar, indicating comparable binding topology and stability. A different CIU fingerprint is observed for PvDBP-II/2C6, indicating that 2C6 binds to PvDBP-II on an epitope different from 2D10 and 2H2. This work supports the use of CIU as a means of classifying antigen-antibody complexes by their epitope maps in a high throughput screening workflow. [Figure not available: see fulltext.

  10. 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....

  11. Highly sensitive radioimmunoassay technique for subtyping the antibody to hepatitis B surface antigen

    Energy Technology Data Exchange (ETDEWEB)

    Fang, C T; Nath, N; Berberian, H; Dodd, R Y [American Red Cross, Blood Research Laboratory, Bethesda, MD, USA

    1978-12-01

    A highly sensitive technique for determining the subtype specificity of antibody to hepatitis B surface antigen (anti-HBs) is described. Immunoadsorbent consisting of controlled pore glass coated with subtype specific HBsAg was used to remove homologous antibody from the test samples before testing them for residual antibody by a commercially available radioimmunoassay (RIA). A total of 73 anti-HBs-positive samples from asymptomatic blood donors were tested. In nearly 80% of these samples the subtype reactivity could be determined by this technique. Only 67% could be typed by conventional liquid phase absorption RIA and 22% by passive hemagglutination inhibition techniques. Among the samples with low anti-HBs titer, ad and ay subtypes were found with equal frequency; however, with the increase in anti-HBs titer, considerably higher proportion of ad specificity was detected.

  12. A highly sensitive radioimmunoassay technique for subtyping the antibody to hepatitis B surface antigen

    International Nuclear Information System (INIS)

    Fang, C.T.; Nath, N.; Berberian, H.; Dodd, R.Y.

    1978-01-01

    A highly sensitive technique for determining the subtype specificity of antibody to hepatitis B surface antigen (anti-HBs) is described. Immunoadsorbent consisting of controlled pore glass coated with subtype specific HBsAg was used to remove homologous antibody from the test samples before testing them for residual antibody by a commercially available radioimmunoassay (RIA). A total of 73 anti-HBs-positive samples from asymptomatic blood donors were tested. In nearly 80% of these samples the subtype reactivity could be determined by this technique. Only 67% could be typed by conventional liquid phase absorption RIA and 22% by passive hemagglutination inhibition techniques. Among the samples with low anti-HBs titer, ad and ay subtypes were found with equal frequency; however, with the increase in anti-HBs titer, considerably higher proportion of ad specificity was detected. (Auth.)

  13. Radioimmunolocalisation of tumours by external scintigraphy after administration of 131I antibody to carcinoembryonic antigen

    International Nuclear Information System (INIS)

    Searle, F.; Bagshawe, K.D.; Begent, R.H.J.; Jewkes, R.F.; Jones, B.E.; Keep, P.A.; Lewis, J.; Vernon, P.

    1980-01-01

    Investigations of 131 I-labelled antibody to carcinoembryonic antigen (CEA) were performed in nude mice bearing human colonic carcinoma xenografts and in external scintigraphy of patients with various tumours. In mice, the activities of 131 I (antiCEA) and 125 I(normal γ globulin) were measured in the human colon carcinoma xenografts. The results were expressed as a ratio of uptake of specific to non-specific antibody showing that antiCEA was retained in the tumours with a maximum specificity index of 2.2 at 7 days after antibody administration. Palpable carcinomas of the colon were localised by scintiscanning in patients given 131 I-labelled antibody to CEA. However, uptake of antiCEA was also demonstrated in apparently normal colon due to non-specific uptake of antibody and the fact that some CEA is present in normal colon. Thus further development of the technique particularly as regards antibody specificity, is necessary before radioimmunolocalisation could be used as a means of detecting tumours in clinical practice. (UK)

  14. Single-dilution enzyme-linked immunosorbent assay for quantification of antigen-specific salmonid antibody

    Science.gov (United States)

    Alcorn, S.W.; Pascho, R.J.

    2000-01-01

    An enzyme-linked immunosorbent assay (ELISA) was developed on the basis of testing a single dilution of serum to quantify the level of antibody to the p57 protein of Renibaclerium salmoninarum in sockeye salmon (Oncorhynchus nerka). The levels of antibody were interpolated from a standard curve constructed by relating the optical densities (OD) produced by several dilutions of a high-titer rainbow trout (O. mykiss) antiserum to the p57 protein. The ELISA OD values produced by as many as 36 test sera on each microplate were compared with the standard curve to calculate the antigen-specific antibody activity. Repeated measurements of 36 samples on 3 microplates on each of 6 assay dates indicated that the mean intraassay coefficient of variation (CV) was 6.68% (range, 0-23%) and the mean interassay CV was 8.29% (range, 4-16%). The antibody levels determined for the serum sample from 24 sockeye salmon vaccinated with a recombinant p57 protein generally were correlated with the levels determined by endpoint titration (r2 = 0.936) and with results from another ELISA that was based on extrapolation of antibody levels from a standard curve (r2 = 0.956). The single-dilution antibody ELISA described here increases the number of samples that can be tested on each microplate compared with immunoassays based on analysis of several dilutions of each test serum. It includes controls for interassay standardization and can be used to test fish weighing <3 g.

  15. 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...

  16. Sero-prevalence of Taenia solium cysticercosis and Taenia solium taeniasis in California, USA.

    Science.gov (United States)

    DeGiorgio, C; Pietsch-Escueta, S; Tsang, V; Corral-Leyva, G; Ng, L; Medina, M T; Astudillo, S; Padilla, N; Leyva, P; Martinez, L; Noh, J; Levine, M; del Villasenor, R; Sorvillo, F

    2005-02-01

    Taenia solium Cysticercosis is a leading cause of epilepsy and neurological disability in the developing world. It is caused by ingestion of the eggs of the tapeworm, T. solium Taeniasis. The prevalence of either T. solium Cysticercosis or T. solium Taeniasis in the United States in populations at risk is poorly understood. The primary objectives of this study are to perform the first study of the sero-prevalence of T. solium Cysticercosis and T. solium Taeniasis in an at-risk community in the USA, specifically rural Southern California; identify T. solium Taeniasis positive individuals, and treat positive individuals for the tapeworm T. solium Taeniasis. Community based sero-prevalence study of antibodies to T. solium Cysticercosis and T. solium Taeniasis in 449 subjects living in a federally funded, predominantly Hispanic residential community; and in two migrant farm worker camps in rural Ventura County, California, USA. For this study, fingerstick blood samples were obtained. Serum immunoblots for both T. solium Cysticercosis and T. solium Taeniasis were performed. The sero-prevalence of T. solium Cysticercosis was 1.8% and the sero-prevalence of T. solium Taeniasis by serum immunoblot was 1.1%. Taenia solium Cysticercosis and T. solium Taeniasis antibodies were not detected in children. The sero-prevalence of T. solium Taeniasis was highest in the migrant farm worker community. Handwashing frequency was correlated with T. solium Taeniasis sero-positivity. The sero-prevalence of T. solium Cysticercosis and T. solium Taeniasis in this population, as detected by serum immunoblot, approximates the prevalence in some endemic areas of Latin America. Importantly, most patients likely had prior exposure, not active infection. This study establishes for the first time, the relative sero-prevalence of T. solium Cysticercosis and T. solium Taeniasis in at-risk populations in the United States.

  17. Purification of antibodies to bacterial antigens by an immunoadsorbent and a method to quantify their reaction with insoluble bacterial targets

    International Nuclear Information System (INIS)

    Mathews, H.L.; Minden, P.

    1979-01-01

    A combination of procedures was employed to develop a radioimmunoassay which quantified the binding of antibodies to antigens of either intact Propionibacterium acnes or to antigens of insoluble extracts derived from the bacteria. Reactive antibody populations were purified by use of bacterial immunoadsorbents which were prepared by coupling P. acnes to diethylaminoethyl cellulose. Binding of antibodies was detected with [ 125 I]staphylococcal protein A ([ 125 I]SpA) and optimal conditions for the assay defined by varying the amounts of antibodies, bacterial antigenic targets and [ 125 I]SpA. In antibody excess, 100% of available [ 125 I]SpA was bound by the target-antibody complexes. However, when antibody concentration was limiting, a linear relationship was demonstrated between per cent specific binding of[ 125 I]SpA and antibodies bound to bacterial targets. These results were achieved only with immunoadsorbent-purified antibody populations and not with hyperimmune sera or IgG. The radioimmunoassay detected subtle antigenic differences and similarities between P. acnes, P. acnes extracts and a variety of unrelated microorganisms. (Auth.)

  18. 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

  19. Antibody response to the lipopolysaccharide and protein antigens of Salmonella typhi during typhoid infection. I. Measurement of serum antibodies by radioimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Tsang, R S.W.; Chau, P Y; Lam, S K [Hong Kong Univ.; La Brooy, J T; Rowley, D [Adelaide Univ. (Australia)

    1981-12-01

    Serum antibody responses to the lipopolysaccharide and protein antigens of S. typhi in typhoid patients were studied using a solid-phase radioimmunoassay technique with /sup 125/I labelled anti-immunoglobulin antibody. Sera from 24 adult typhoid patients and 20 non-typhoid adult controls were compared. As a group, sera from typhoid patients showed increased IgA, IgG and IgM immunoglobulin levels and gave significantly higher anti-LPS and anti-protein antibody titres in all three major immunoglobulin classes than did non-typhoid controls. Levels of antibodies against LPS or protein in sera of typhoid patients were highly variable with a skew distribution. A good correlation was found between antibody titres to the LPS antigen and those to a protein antigen. No correlation, however, was found between the anti-LPS antibody titres measured by radioimmunoassay and the anti-O antibody titres measured by the Widal agglutination test. Titration of anti-LPS or anti-protein antibodies by radioimmunoassay was found to be more sensitive and specific than Widal test for the serological diagnosis of typhoid fever. The advantages of measuring antibody response by radioimmunoassay over conventional Widal test are discussed.

  20. 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.

  1. Standardization and validation of a cytometric bead assay to assess antibodies to multiple Plasmodium falciparum recombinant antigens.

    Science.gov (United States)

    Ondigo, Bartholomew N; Park, Gregory S; Gose, Severin O; Ho, Benjamin M; Ochola, Lyticia A; Ayodo, George O; Ofulla, Ayub V; John, Chandy C

    2012-12-21

    Multiplex cytometric bead assay (CBA) have a number of advantages over ELISA for antibody testing, but little information is available on standardization and validation of antibody CBA to multiple Plasmodium falciparum antigens. The present study was set to determine optimal parameters for multiplex testing of antibodies to P. falciparum antigens, and to compare results of multiplex CBA to ELISA. Antibodies to ten recombinant P. falciparum antigens were measured by CBA and ELISA in samples from 30 individuals from a malaria endemic area of Kenya and compared to known positive and negative control plasma samples. Optimal antigen amounts, monoplex vs multiplex testing, plasma dilution, optimal buffer, number of beads required were assessed for CBA testing, and results from CBA vs. ELISA testing were compared. Optimal amounts for CBA antibody testing differed according to antigen. Results for monoplex CBA testing correlated strongly with multiplex testing for all antigens (r = 0.88-0.99, P values from <0.0001 - 0.004), and antibodies to variants of the same antigen were accurately distinguished within a multiplex reaction. Plasma dilutions of 1:100 or 1:200 were optimal for all antigens for CBA testing. Plasma diluted in a buffer containing 0.05% sodium azide, 0.5% polyvinylalcohol, and 0.8% polyvinylpyrrolidone had the lowest background activity. CBA median fluorescence intensity (MFI) values with 1,000 antigen-conjugated beads/well did not differ significantly from MFI with 5,000 beads/well. CBA and ELISA results correlated well for all antigens except apical membrane antigen-1 (AMA-1). CBA testing produced a greater range of values in samples from malaria endemic areas and less background reactivity for blank samples than ELISA. With optimization, CBA may be the preferred method of testing for antibodies to P. falciparum antigens, as CBA can test for antibodies to multiple recombinant antigens from a single plasma sample and produces a greater range of values in

  2. Antibodies reactive to Plasmodium falciparum serine repeat antigen in children with Burkitt lymphoma from Ghana.

    Science.gov (United States)

    Guech-Ongey, Mercy; Yagi, Masanori; Palacpac, Nirianne Marie Q; Emmanuel, Benjamin; Talisuna, Ambrose O; Bhatia, Kishor; Stefan, D Cristina; Biggar, Robert J; Nkrumah, Francis; Neequaye, Janet; Tougan, Takahiro; Horii, Toshihiro; Mbulaiteye, Sam M

    2012-04-15

    The role of protective immunity to Plasmodium falciparum (Pf) malaria in Burkitt lymphoma (BL) is unknown. We investigated the association between BL and antibodies reactive to SE36 antigen, a recombinant protein based on P. falciparum serine repeat antigen 5 gene, targeted by protective malaria immune responses. Cases were children (0-14 years) enrolled at the Korle-Bu Teaching Hospital, Accra, Ghana, during 1965-1994 with BL confirmed by histology or cytology (92% of cases). Controls were apparently healthy children enrolled contemporaneous to the cases from the nearest neighbor house to the case house and were age,- sex-frequency-matched to the cases. Anti-SE36 IgG antibodies were measured using enzyme-linked absorbent immunoassays (ELISAs). SE36 titers were estimated by extrapolating ELISA optical density readings to a standard fitting curve. Anti-SE36 titers were log-transformed for analysis. Odds ratios (ORs) and two-sided 95% confidence intervals (95% CIs) were estimated using unconditional logistic regression. The mean log endpoint dilution titers were 0.63 logs lower in cases than in controls (8.26 [SD 1.68] vs. 8.89 [SD 1.75], Student's t-test, p = 0.019). Lower titers were observed in cases than controls aged 0-4 years (p = 0.05) and in those aged 5-14 years (p = 0.06). Low and medium tertiles of anti-SE36 IgG antibodies were associated with increased OR for BL ([OR 1.67, 95% CI 1.21-2.31] and [OR 1.33, 95% CI 0.96-1.86], respectively, p(trend) = 0.002) in analyses adjusting for age, sex, calendar period and test plate. Our findings suggest that compared to similarly aged children enrolled from the same community, children with BL in Ghana have lower antibodies to SE36 antigen. Copyright © 2011 UICC.

  3. 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)

  4. Adoptive transfer of natural antibodies to non-immunized chickens affects subsequent antigen-specific humoral and cellular immune responses

    NARCIS (Netherlands)

    Lammers, A.; Klomp, M.E.V.; Nieuwland, M.G.B.; Savelkoul, H.F.J.; Parmentier, H.K.

    2004-01-01

    To determine a regulatory function of natural antibodies in the immune response of chickens, pooled plasma obtained from non-immunized (naive) 15 months old hens was subjected to keyhole limpet hemocyanin (KLH) antigen-affinity chromatography. Purified KLH-binding antibodies were adoptively

  5. Distribution of 125I-monoclonal antibodies to antigen Ly 2.1 of T-lymphocytes in mice under the influence of immunomodulators

    International Nuclear Information System (INIS)

    Mirolyubova, Sh.Yu.; Fadeev, N.P.; Serzhanina, V.A.; Klimovich, V.B.; Makarenko, M.V.; Korsakova, L.N.

    1991-01-01

    A study was made of the distribution of 125 I (a chloramine method of labelling) monoclonal antibodies to the surface antigen Ly 2.1 T-lymphocytes during action of immunomodulators (tactivin, hydrocortisone, tactivin administered after hydrocortisone) on ACR mice. These antibodies were shown to retain antigen binding capacity, permitting monitoring of the redistribution of the antigen in the body exposed to immunomodulators

  6. Cysticercosis. A modern day plague.

    Science.gov (United States)

    Brown, W J; Voge, M

    1985-08-01

    The authors describe the magnitude of the cysticercosis problem and describe the organism, the clinical features of the disease, the propensity of the organism for development in the central nervous system, pathologic considerations, clinical diagnosis, and treatment.

  7. Ontogeny of adaptive antibody response to a model antigen in captive altricial zebra finches.

    Directory of Open Access Journals (Sweden)

    Tess L Killpack

    Full Text Available Based on studies from the poultry literature, all birds are hypothesized to require at least 4 weeks to develop circulating mature B-cell lineages that express functionally different immunoglobulin specificities. However, many altricial passerines fledge at adult size less than four weeks after the start of embryonic development, and therefore may experience a period of susceptibility during the nestling and post-fledging periods. We present the first study, to our knowledge, to detail the age-related changes in adaptive antibody response in an altricial passerine. Using repeated vaccinations with non-infectious keyhole limpet hemocyanin (KLH antigen, we studied the ontogeny of specific adaptive immune response in altricial zebra finches Taeniopygia guttata. Nestling zebra finches were first injected at 7 days (7d, 14 days (14d, or 21 days post-hatch (21d with KLH-adjuvant emulsions, and boosted 7 days later. Adults were vaccinated in the same manner. Induced KLH-specific IgY antibodies were measured using ELISA. Comparisons within age groups revealed no significant increase in KLH-specific antibody levels between vaccination and boost in 7d birds, yet significant increases between vaccination and boost were observed in 14d, 21d, and adult groups. There was no significant difference among age groups in KLH antibody response to priming vaccination, yet KLH antibody response post-boost significantly increased with age among groups. Post-boost antibody response in all nestling age groups was significantly lower than in adults, indicating that mature adult secondary antibody response level was not achieved in zebra finches prior to fledging (21 days post-hatch in zebra finches. Findings from this study contribute fundamental knowledge to the fields of developmental immunology and ecological immunology and strengthen the utility of zebra finches as a model organism for future studies of immune ontogeny.

  8. Characterization of ELISA Antibody-Antigen Interaction using Footprinting-Mass Spectrometry and Negative Staining Transmission Electron Microscopy

    Science.gov (United States)

    Lin, Margaret; Krawitz, Denise; Callahan, Matthew D.; Deperalta, Galahad; Wecksler, Aaron T.

    2018-05-01

    We describe epitope mapping data using multiple covalent labeling footprinting-mass spectrometry (MS) techniques coupled with negative stain transmission electron microscopy (TEM) data to analyze the antibody-antigen interactions in a sandwich enzyme-linked immunosorbant assay (ELISA). Our hydroxyl radical footprinting-MS data using fast photochemical oxidation of proteins (FPOP) indicates suppression of labeling across the antigen upon binding either of the monoclonal antibodies (mAbs) utilized in the ELISA. Combining these data with Western blot analysis enabled the identification of the putative epitopes that appeared to span regions containing N-linked glycans. An additional structural mapping technique, carboxyl group footprinting-mass spectrometry using glycine ethyl ester (GEE) labeling, was used to confirm the epitopes. Deglycosylation of the antigen resulted in loss of potency in the ELISA, supporting the FPOP and GEE labeling data by indicating N-linked glycans are necessary for antigen binding. Finally, mapping of the epitopes onto the antigen crystal structure revealed an approximate 90° relative spatial orientation, optimal for a noncompetitive binding ELISA. TEM data shows both linear and diamond antibody-antigen complexes with a similar binding orientation as predicted from the two footprinting-MS techniques. This study is the first of its kind to utilize multiple bottom-up footprinting-MS techniques and TEM visualization to characterize the monoclonal antibody-antigen binding interactions of critical reagents used in a quality control (QC) lot-release ELISA. [Figure not available: see fulltext.

  9. Characterization of ELISA Antibody-Antigen Interaction using Footprinting-Mass Spectrometry and Negative Staining Transmission Electron Microscopy

    Science.gov (United States)

    Lin, Margaret; Krawitz, Denise; Callahan, Matthew D.; Deperalta, Galahad; Wecksler, Aaron T.

    2018-03-01

    We describe epitope mapping data using multiple covalent labeling footprinting-mass spectrometry (MS) techniques coupled with negative stain transmission electron microscopy (TEM) data to analyze the antibody-antigen interactions in a sandwich enzyme-linked immunosorbant assay (ELISA). Our hydroxyl radical footprinting-MS data using fast photochemical oxidation of proteins (FPOP) indicates suppression of labeling across the antigen upon binding either of the monoclonal antibodies (mAbs) utilized in the ELISA. Combining these data with Western blot analysis enabled the identification of the putative epitopes that appeared to span regions containing N-linked glycans. An additional structural mapping technique, carboxyl group footprinting-mass spectrometry using glycine ethyl ester (GEE) labeling, was used to confirm the epitopes. Deglycosylation of the antigen resulted in loss of potency in the ELISA, supporting the FPOP and GEE labeling data by indicating N-linked glycans are necessary for antigen binding. Finally, mapping of the epitopes onto the antigen crystal structure revealed an approximate 90° relative spatial orientation, optimal for a noncompetitive binding ELISA. TEM data shows both linear and diamond antibody-antigen complexes with a similar binding orientation as predicted from the two footprinting-MS techniques. This study is the first of its kind to utilize multiple bottom-up footprinting-MS techniques and TEM visualization to characterize the monoclonal antibody-antigen binding interactions of critical reagents used in a quality control (QC) lot-release ELISA. [Figure not available: see fulltext.

  10. The antibody response to well-defined malaria antigens after acute malaria in individuals living under continuous malaria transmission

    DEFF Research Database (Denmark)

    Petersen, E; Høgh, B; Dziegiel, M

    1992-01-01

    The IgG and IgM antibody responses to the C-terminal 783 amino acids of the P. falciparum glutamate-rich protein, GLURP489-1271, expressed as an E. coli fusion protein, the IgG response to a 18-mer synthetic peptide EDKNEKGQHEIVEVEEIL (GLURP899-916) representing the C-terminal repeats of GLURP......, and a synthetic peptide (EENV)6 representing the C-terminal repeats from Pf155/RESA, were investigated longitudinally in 13 children and 7 adults living under conditions of continuous, intense malaria transmission. Some subjects did not recognize the antigens after malaria infection, and in subjects recognizing...... the antigens, the responses were often short-lived. In adults, the antibody responses to the GLURP489-1271 fusion protein and the (EENV)6 peptide peaked after 2 weeks, and not all individuals responded to all antigens. The antibody response, even against large fragments of conserved antigens, is not uniformly...

  11. Cysticercosis of the nervous system. Treatment by means of specific internal radiation

    International Nuclear Information System (INIS)

    Skromne-Kadlubik, G.; Celis, C.

    1981-01-01

    Five hundred patients with cysticercosis of the nervous system were evaluated by scanning that used anti-Cysticercus antibodies labeled with indium 113. The same antibodies, labeled with iodine 131, were used for radioimmunotreatment. Ninety-six percent of the patients had good or excellent results, whereas only 4% had poor results. None of the patients showed intolerance or radiotoxicity during three months of clinical and laboratory follow-up. The diagnosis, treatment, and prognosis of cysticercosis of the nervous system are dramatically changing, due to the development of anti-Cysticercus antibodies labeled with radionuclides

  12. Porcine Cysticercosis and Risk Factors in The Gambia and Senegal

    Directory of Open Access Journals (Sweden)

    Arss Secka

    2010-01-01

    Full Text Available During a stratified cross-sectional survey, 1705 pigs were sampled from 279 randomly selected households, 63 randomly selected communities and villages, from four study areas in The Gambia and Senegal during the period October 2007 to January 2008. Porcine cysticercosis prevalence detected by tongue inspection at animal level per study area ranged from 0.1% to 1.0%. Using an antigen-detection ELISA the seroprevalence of cysticercosis at both community/village and animal levels for the four selected study areas is: Western region 80.0% (95%CI: 52.4%–93.6% and 4.8% (95%CI: 3.4%–6.5%, Bignona 86.7% (95%CI: 59.8%–96.6% and 8.9% (95%CI: 5.0%–15.5%, Kolda 82.4% (95%CI: 46.8%–96.1% and 13.2% (95%CI: 10.8%–16.0%, and Ziguinchor 81.3% (95%CI: 43.5%–96.1% and 6.4% (95%CI: 4.0%–10.1%, respectively. No risk factors for cysticercosis were found significant in this study. This study proved that porcine cysticercosis is endemic and distributed widely in the study areas though its incidence might be suppressed by the generalised use of toilets and latrines in the study areas.

  13. The effect of high antigen density on solid-phase radioimmunoassays for antibody regardless of immunoglobulin class

    International Nuclear Information System (INIS)

    Rubin, R.L.; Hardtke, M.A.; Carr, R.I.

    1980-01-01

    Human sera containing antibody to casein or to bovine serum albumin were used to assess the validity and utility of a solid-phase assay for quantitating antibody activity. Rabbit anti-human immunoglobulin radiolabeled with 125 I and capable of reacting with all human immunoglobulin classes was used to detect antibody bound to antigen immobilized to polystyrene tubes by a new covalent technique. This method results in very high antigen concentrations in highly stable association with polystyrene tubes. Kinetic and absorption studies demonstrated that low avidity antibodies are better detected when antigen is immobilized by the covalent method than when passively adsorbed. Conditions are described for minimizing artifactual interactions and for obtaining results similar to those obtained with conventional, liquid-phase assays. Failure to reach equilibrium in solid-phase assays and other problems are proposed to explain, in part, the inability to obtain a better correlation between solid- and liquid-phase immunoassays. (Auth.)

  14. Affinity isolation of antigen-specific circulating B cells for generation of phage display-derived human monoclonal antibodies

    DEFF Research Database (Denmark)

    Ditzel, Henrik

    2009-01-01

    A method is described for affinity isolation of antigen-specific circulating B cells of interest for subsequent generation of immune antibody phage display libraries. This approach should overcome the problem of low yields of monoclonal antibodies of interest in the libraries generated from...... peripheral blood lymphocytes caused by the low abundance of antigen-specific B cells in the circulation. The preselection of B cells is based on the specificity of the surface Ig receptor and is accomplished using the antigen of interest conjugated to magnetic beads. This method should significantly increase...... the frequency of antibody phage particles of interest in the library and allow for efficient isolation monoclonal antibodies with the predefined specificity....

  15. Temporal relation of antigenaemia and loss of antibodies to core antigens to development of clinical disease in HIV infection

    DEFF Research Database (Denmark)

    Pedersen, C; Nielsen, C M; Vestergaard, B F

    1987-01-01

    and 16 months after the estimated time of seroconversion. These results show that the late stages of HIV infection are characterised by increased production of antigen and a decrease in antibodies directed against the core protein. Antigenaemia indicates a poor prognosis; and as the antigen test......A total of 276 sequential serum samples from 34 men with antibodies to the human immunodeficiency virus (HIV) followed up for two to seven years were analysed for HIV antigen and antibodies to the viral core and envelope proteins. Results were correlated with clinical outcome and CD4 T lymphocyte...... count. Both antigenaemia and the disappearance of antibodies to the core protein were associated with development of the acquired immune deficiency syndrome (AIDS) or AIDS related complex and depletion of CD4 cells. Thus AIDS or AIDS related complex developed in eight out of 16 patients...

  16. In vivo localization of radiolabeled monoclonal antibody to carcinoembryonic antigen (CEA) in a CEA-producing tumor

    International Nuclear Information System (INIS)

    Kamei, Tetsuya; Seto, Hikaru; Taki, Kuniyasu; Soya, Toshio; Kakishita, Masao; Maeda, Masatoshi; Honda, Takashi; Koshimura, Saburou.

    1987-01-01

    To compare accumulation of the 125 I-labeled antibodies(anti-carcinoembryonic antigen(CEA) monoclonal antibody and polyclonal antibody) to a CEA-producing tumor (SC-2-JCK), an in vivo localization study was performed in nude mice. The tumor-to-blood ratio at 120 hours after injection rose to 4.6 for the monoclonal antibody, but remained at 1.3 for the polyclonal antibody. However, no differences were noted between the antibodies up to 72 hours after injection. In autoradiograms, selective accumulation of the tracer was noted in the tumor for both antibodies. However, no superiority or inferiority of imaging for either of the antibodies could be definitely determined. (author)

  17. Taenia solium taeniasis and cysticercosis in three communities in north Vietnam.

    Science.gov (United States)

    Somers, R; Dorny, P; Nguyen, V K; Dang, T C T; Goddeeris, B; Craig, P S; Vercruysse, J

    2006-01-01

    (1) To investigate the response to a serum antigen-detecting ELISA for cysticercosis and a stool coproantigen test for taeniasis in two rural communities (mountainous and coastal areas) and one group of (peri-)urban factory workers; and (2) to examine clinical features of human cysticercosis in northern Vietnam. Villagers and factory workers and their families were informed and invited to participate in the study. Blood and faecal samples were collected from the participants and a simple questionnaire on taeniasis/cysticercosis completed. Serum was examined for the presence of circulating cysticercus antigen by a monoclonal-based sandwich ELISA. Ag-ELISA positive persons underwent a clinical examination and a computed tomography (CT) scan. Stool samples were examined microscopically for the presence of Taenia eggs and for copro-antigens. Tapeworms were identified following therapeutic expulsion using morphology and PCR-RFLP. Circulating cysticercus antigens, suggesting active infection, were detected in 5.3% (16/303), 0.6% (1/175) and 0.0% (0/229) of the sampled individuals from the mountainous, coastal and urban regions, respectively. Clinical examination and CT scan of the cysticercus antigen positive persons showed that active cysticercosis did not cause severe disease in most cases. Taenia copro-antigens were found in 0.3% (1/297), 1.8% (3/166) and 0.0% (0/228) of the stool samples from the mountainous, coastal and urban communities, respectively. Three tapeworms were expelled after treatment: two Taenia solium and one Taenia saginata. This survey points to a focal distribution of taeniasis/cysticercosis and suggests that human cysticercosis is rather acquired due to close contact with a T. solium carrier and self-infection, than through infection from the environment.

  18. Systemic and Mucosal Antibody Responses to Soluble and Nanoparticle-Conjugated Antigens Administered Intranasally

    Directory of Open Access Journals (Sweden)

    Savannah E. Howe

    2016-10-01

    Full Text Available Nanoparticles (NPs are increasingly being used for drug delivery, as well as antigen carriers and immunostimulants for the purpose of developing vaccines. In this work, we examined how intranasal (i.n. priming followed by i.n. or subcutaneous (s.c. boosting immunization affects the humoral immune response to chicken ovalbumin (Ova and Ova conjugated to 20 nm NPs (NP-Ova. We show that i.n. priming with 20 mg of soluble Ova, a dose known to trigger oral tolerance when administered via gastric gavage, induced substantial systemic IgG1 and IgG2c, as well as mucosal antibodies. These responses were further boosted following a s.c. immunization with Ova and complete Freund’s adjuvant (Ova+CFA. In contrast, 100 µg of Ova delivered via NPs induced an IgG1-dominated systemic response, and primed the intestinal mucosa for secretion of IgA. Following a secondary s.c. or i.n. immunization with Ova+CFA or NP-Ova, systemic IgG1 titers significantly increased, and serum IgG2c and intestinal antibodies were induced in mice primed nasally with NP-Ova. Only Ova- and NP-Ova-primed mice that were s.c.-boosted exhibited substantial systemic and mucosal titers for up to 6 months after priming, whereas the antibodies of i.n.-boosted mice declined over time. Our results indicate that although the amount of Ova delivered by NPs was 1000-fold less than Ova delivered in soluble form, the antigen-specific antibody responses, both systemic and mucosal, are essentially identical by 6 months following the initial priming immunization. Additionally, both i.n.- and s.c.-boosting strategies for NP-Ova-primed mice were capable of inducing a polarized Th1/Th2 immune response, as well as intestinal antibodies; however, it is only by using a heterogeneous prime-boost strategy that long-lasting antibody responses were initiated. These results provide valuable insight for future mucosal vaccine development, as well as furthering our understanding of mucosal antibody responses.

  19. Reduced antibody responses against Plasmodium falciparum vaccine candidate antigens in the presence of Trichuris trichiura

    DEFF Research Database (Denmark)

    Esen, Meral; Mordmüller, Benjamin; de Salazar, Pablo Martinez

    2012-01-01

    BACKGROUND: Helminth infections are highly prevalent in the tropics and may have an effect on immune responses to vaccines due to their immunomodulatory effect. The prevalence of helminth infections in young children, the target group for malaria and most other vaccines, is high. Therefore we...... assessed the influence of helminth infection on vaccine-induced immune responses in a phase I clinical trial of the malaria vaccine candidate GMZ2. METHODS: Twenty Gabonese preschool-age children were vaccinated with GMZ2, a blood stage malaria vaccine candidate. Humoral immune response against the vaccine...... antigens and parasitological status were assessed. Vaccine-specific antibody concentrations and memory B-cell numbers were compared in worm infected and non-infected participants. RESULTS: Antibody response to GMZ2 was 3.4-fold (95% confidence interval: 1.6, 7.4) higher in Trichuris trichiura negative...

  20. Radioimmunoassay and characterization of woodchuck hepatitis virus core antigen and antibody

    Energy Technology Data Exchange (ETDEWEB)

    Ponzetto, A; Cote, P J; Ford, E C; Engle, R; Gerin, J L; Cicmanec, J; Shapiro, M; Purcell, R H

    1985-06-01

    Solid-phase radioimmunoassays for woodchuck hepatitis virus core antigen (WHcAg) and antibody (anti-WHc) were developed. WHcAg in woodchuck liver homogenates was characterized by ultracentrifugation in CsCl gradients; both heavy and light cores were obtained from the liver of an animal during acute WHV infection, which is consistent with observations in hepatitis B virus infection in man. Endpoint titers of anti-WHc were higher in chronic WHV carriers than in animals recovered from acute infections. Both IgM and IgG anti-WHc antibodies were produced by infected woodchucks. A survey of colony woodchucks demonstrated that 88/89 animals having one or more markers of past or ongoing WHV infection were positive for anti-WHc. Thus, serum anti-WHc appears to be a sensitive marker of WHV infection.

  1. Mobile myelographic filling defects: Spinal cysticercosis

    Energy Technology Data Exchange (ETDEWEB)

    Savoiardo, M.; Cimino, C.; Passerini, A.; La Mantia, L.

    1986-03-01

    Cysticercosis usually affects the brain and is easily demonstrated by CT. Spinal cysticercosis is much rarer and is usually diagnosed only at surgery. Myelographic demonstration of multiple rounded filling defects, some of which were mobile, allowed diagnosis of spinal extramedullary cysticercosis in an unsuspected case. The literature on spinal cysticercosis is briefly reviewed. Diagnosis is important in view of the recent development of medical treatment.

  2. Identification of an antigenic domain on Mycobacterium leprae protein antigen 85B, which is specifically recognized by antibodies from patients with leprosy

    NARCIS (Netherlands)

    Filley, E.; Thole, J. E.; Rook, G. A.; Nagai, S.; Waters, M.; Drijfhout, J. W.; Rinke de Wit, T. F.; de Vries, R. R.; Abou-Zeid, C.

    1994-01-01

    Sixty-three overlapping 15-oligomer peptides covering the 30-kDa protein antigen 85B of Mycobacterium leprae were tested by ELISA to identify epitopes recognized by human antibodies. Serum samples from patients with lepromatous leprosy (LL) reacted mainly with peptides comprising amino acid regions

  3. Acute HIV Discovered During Routine HIV Screening With HIV Antigen-Antibody Combination Tests in 9 US Emergency Departments.

    Science.gov (United States)

    White, Douglas A E; Giordano, Thomas P; Pasalar, Siavash; Jacobson, Kathleen R; Glick, Nancy R; Sha, Beverly E; Mammen, Priya E; Hunt, Bijou R; Todorovic, Tamara; Moreno-Walton, Lisa; Adomolga, Vincent; Feaster, Daniel J; Branson, Bernard M

    2018-01-05

    Newer combination HIV antigen-antibody tests allow detection of HIV sooner after infection than previous antibody-only immunoassays because, in addition to HIV-1 and -2 antibodies, they detect the HIV-1 p24 antigen, which appears before antibodies develop. We determine the yield of screening with HIV antigen-antibody tests and clinical presentations for new diagnoses of acute and established HIV infection across US emergency departments (EDs). This was a retrospective study of 9 EDs in 6 cities with HIV screening programs that integrated laboratory-based antigen-antibody tests between November 1, 2012, and December 31, 2015. Unique patients with newly diagnosed HIV infection were identified and classified as having either acute HIV infection or established HIV infection. Acute HIV infection was defined as a repeatedly reactive antigen-antibody test result, a negative HIV-1/HIV-2 antibody differentiation assay, or Western blot result, but detectable HIV ribonucleic acid (RNA); established HIV infection was defined as a repeatedly reactive antigen-antibody test result and a positive HIV-1/HIV-2 antibody differentiation assay or Western blot result. The primary outcomes were the number of new HIV diagnoses and proportion of patients with laboratory-defined acute HIV infection. Secondary outcomes compared reason for visit and the clinical presentation of acute HIV infection. In total, 214,524 patients were screened for HIV and 839 (0.4%) received a new diagnosis, of which 122 (14.5%) were acute HIV infection and 717 (85.5%) were established HIV infection. Compared with patients with established HIV infection, those with acute HIV infection were younger, had higher RNA and CD4 counts, and were more likely to have viral syndrome (41.8% versus 6.5%) or fever (14.3% versus 3.4%) as their reason for visit. Most patients with acute HIV infection displayed symptoms attributable to acute infection (median symptom count 5 [interquartile range 3 to 6]), with fever often

  4. Anti-D Antibodies in Pregnant D Variant Antigen Carriers Initially Typed as RhD.

    Science.gov (United States)

    Lukacevic Krstic, Jelena; Dajak, Slavica; Bingulac-Popovic, Jasna; Dogic, Vesna; Mratinovic-Mikulandra, Jela

    2016-11-01

    To evaluate the incidence, the consequences, and the prevention strategy of anti-D alloimmunizations of D variant carriers in the obstetric population of Split-Dalmatia County, Croatia. RhD immunization events were evaluated retrospectively for the period between 1993 and 2012. Women were tested for RhD antigen and irregular antibodies. Those with anti-D antibody who were not serologically D- were genotyped for RHD. They were evaluated for their obstetric and transfusion history and their titer of anti-D. The neonates were evaluated for RhD status, direct antiglobulin test (DAT), hemoglobin and bilirubin levels, transfusion therapy as well as phototherapy and outcome. Out of 104,884 live births 102,982 women were tested for RhD antigen. Anti-D immunization occurred in 184 women which accounts for 0.9% of individuals at risk of anti-D formation. 181 cases occurred in women serologically typed as D-. Three women were partial D carriers (DVa n = 2, DNB n = 1), initially typed RhD+, and recognized as D variant carriers after the immunization occurred. Anti-D titer varied from 1:1 to 1:16. Six children were RhD+, four had positive DAT, and two underwent phototherapy. Anti-D immunization occurred in pregnant partial D carriers (DVa, DNB). RhD+ children had serologic markers of hemolytic disease of the fetus and newborn (HDFN), with no cases of severe HDFN.

  5. Evaluation of performance of human immunodeficiency virus antigen/antibody combination assays in Taiwan.

    Science.gov (United States)

    Chang, Chun-Kai; Kao, Cheng-Feng; Lin, Pi-Han; Huang, Hui-Lin; Ho, Shu-Yuan; Wong, Kuo-Chen; Lin, Bo-Chang; Yeh, Chang-Ching; Lee, Chia-Yeh; Kao, Chuan-Liang; Lee, Chun-Nan; Chang, Sui-Yuan; Yang, Jyh-Yuan

    2017-08-01

    The fourth-generation human immunodeficiency virus (HIV) combination assay, which can simultaneously detect the presence of anti-HIV antibody and HIV antigen, has been shown to shorten the window period in HIV diagnosis compared with the third-generation HIV antibody immunoassay. This study was aimed to determine the performance of HIV combination assays in Taiwan, where the HIV-1 seroprevalence is 0.007% and HIV-2 infection has never been reported. Performance of three fourth-generation HIV Ag/Ab combination assays (Dia.Pro, Wantai, and Bio-Rad) and one third-generation HIV Ab immunoassay (AxSYM HIV 1/2 gO) was assessed. A total of 152 specimens, including 86 confirmed HIV-seropositive and 66 HIV-seronegative samples, were used in the study. The sensitivity of four assays varied from 98.8% to 100%, and specificity varied from 98.5% to 100%. Performance of the 75 equivocal samples, the HIV status of which was confirmed later, in terms of negative prediction varied from 81.8% to 87.5%. The Bio-Rad and Dia.Pro assays exhibited higher sensitivity for the detection of p24 antigen among the three fourth-generation HIV combination assays. The three fourth-generation HIV Ag/Ab combination assays exhibited better sensitivity, specificity, and negative prediction than the third-generation HIV Ab immunoassay. Copyright © 2015. Published by Elsevier B.V.

  6. News and views on tumor markers: The use of radioactive antibodies against cell-bound antigens

    International Nuclear Information System (INIS)

    Kleist, S. von

    1984-01-01

    It was doubtless due to the phenomenal progress in the field of tumor immunology that took place during the last 20 years, that today we dispose not only of highly sensitive immunological tests like the RIA or EIA, but also of most specific reagents like monospecific polyclonal and monoclonal antibodies. In this context the discovery in human carcinomas of tumor-associated antigens was of prime importance, especially since some of them were found to have clinical relevance as so-called tumor markers. It has been shown that there is a direct correlation between the absolute tumor burden and the blood concentration of these substances. Based on animal models a new technology for tumor and metastases detection was developed in recent years, that used polyvalent or monoclonal antibodies prepared against tumor-associated antigens. This technique called radioimmuno-detection (RAID), especially in the hands of experts, may be superior in many instances to conventional radiology, radionuclide scanning or ultra-sonographic techniques. (orig.) [de

  7. Antigen-decorated shell cross-linked nanoparticles: synthesis, characterization, and antibody interactions.

    Science.gov (United States)

    Joralemon, Maisie J; Smith, Norah L; Holowka, David; Baird, Barbara; Wooley, Karen L

    2005-01-01

    Antigen-decorated shell cross-linked knedel-like nanoparticles (SCKs) were synthesized and studied as multivalent nanoscale surfaces from which antibody-binding units were presented in a manner that was designed to approach virus particle surfaces. The SCK nanostructures were fabricated with control over the number of antigenic groups, from mixed micellization of amphiphilic diblock copolymer building blocks that contained either an antigen (2,4-dinitrophenyl) or an ethylpropionate group at the hydrophilic alpha-chain terminus. Amphiphilic diblock copolymers were synthesized by atom transfer radical polymerization of tert-butyl acrylate and methyl acrylate sequentially from either a 2,4-dinitrophenyl-functionalized initiator or ethyl 2-bromopropionate, followed by selective removal of the tert-butyl groups to afford 2,4-dinitrophenyl-poly(acrylic acid)60-b-poly(methyl acrylate)60 (DNP-PAA(60)-b-PMA60) and poly(acrylic acid)70-b-poly(methyl acrylate) (PAA70-b-PMA70). Micelles were assembled via addition of water to THF solutions of the polymers in 0:1, 1:1, and 1:0 molar ratios of DNP-PAA60-b-PMA60 to PAA70-b-PMA70, followed by dialysis against water. The acrylic acid groups of the micelle coronas were partially cross-linked (nominally 50%) with 2,2'-(ethylenedioxy)bis(ethylamine), in the presence of 1-(3'-dimethylaminopropyl)-3-ethylcarbodiimide methiodide. Following extensive dialysis against water, the 0%, 50%, and 100% dinitrophenylated shell cross-linked nanoparticles (DNP-SCKs) were characterized with dynamic light scattering (DLS), transmission electron microscopy (TEM), atomic force microscopy (AFM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), infrared and UV-vis spectroscopies, and analytical ultracentrifugation (AU). The surface accessibility and bioavailability of the DNP units upon the DNP-SCKs were investigated by performing quenching titrations of fluorescein-labeled IgE antibody in solution and degranulation of Ig

  8. Screening for epitope specificity directly on culture supernatants in the early phase of monoclonal antibody production by an ELISA with biotin-labeled antigen

    DEFF Research Database (Denmark)

    Andersen, Ditte C; Jensen, Charlotte H; Gregersen, Annemette

    2004-01-01

    This report describes an assay for comparison of epitope specificity in groups of monoclonal antibodies against a given antigen. The only prerequisite is the biotin-labeled antigen. One of the monoclonal antibodies is captured onto a plastic surface via a rabbit anti-mouse Ig, and the other...... preincubated with biotinylated antigen. When the two antibodies react with the same epitope subsequent binding of the biotin-labeled antigen is abolished (inhibition). In the cases where no inhibition was observed, the two antibodies were considered to react with distinct, independent epitopes. The obvious...

  9. Significance of Serology by Multi-Antigen ELISA for Tissue Helminthiases in Korea

    Science.gov (United States)

    2017-01-01

    It is clinically important to differentiate tissue-invading helminthiasis. The purpose of this study was to assess the specific immunoglobulin G (IgG) antibody positive rates for clonorchiasis, paragonimiasis, cysticercosis, and sparganosis 4 helminthiases from 1996 to 2006 using multi-antigen enzyme-linked immunosorbent assay (ELISA) in Korea. Results of 6,017 samples, which were referred to our institute for serodiagnosis, were analyzed. The subjects with positive serum IgG antibodies were 1,502 (25.0%) for any of the 4 helminthiases. The overall positive numbers for clonorchiasis, paragonimiasis, cysticercosis, and sparganosis were 728 (12.1%), 166 (2.8%), 729 (12.1%), and 263 (4.4%), respectively. The positive serologic reaction to multi-antigens was determined in 309 (20.6%) of the 1,502 total seropositive subjects. Those with multi-antigen positivity were regarded as positive for the antigen of strongest reaction but cross-reaction to others with weak positive reaction. Annual seropositive rates for those 4 tissue helminthiases ranged from 12.1% to 35.7%. The highest rate was observed in age from 60 to 69 years old and prevalence of men (27.4%; 1,030/3,763) was significantly higher than of women (19.1%; 332/1,741). Hospital records of 165 ELISA positive patients were reviewed to confirm correlation with their clinical diagnosis. Paragonimiasis was highly correlated as 81.8% (9/11), cysticercosis 29.9% (20/67), clonorchiasis 29.0% (20/69), and sparganosis 11.1% (2/18). In conclusion, the multi-antigen ELISA using 4 helminth antigens is useful to differentiate suspected tissue-invading helminthiases, especially ELISA diagnosis of paragonimiasis is reliable. The seropositivity is still high among suspected patients in Korea. PMID:28581268

  10. A recombinant dromedary antibody fragment (VHH or nanobody) directed against human Duffy antigen receptor for chemokines.

    Science.gov (United States)

    Smolarek, Dorota; Hattab, Claude; Hassanzadeh-Ghassabeh, Gholamreza; Cochet, Sylvie; Gutiérrez, Carlos; de Brevern, Alexandre G; Udomsangpetch, Rachanee; Picot, Julien; Grodecka, Magdalena; Wasniowska, Kazimiera; Muyldermans, Serge; Colin, Yves; Le Van Kim, Caroline; Czerwinski, Marcin; Bertrand, Olivier

    2010-10-01

    Fy blood group antigens are carried by the Duffy antigen receptor for chemokines (DARC), a red cells receptor for Plasmodium vivax broadly implicated in human health and diseases. Recombinant VHHs, or nanobodies, the smallest intact antigen binding fragment derivative from the heavy chain-only antibodies present in camelids, were prepared from a dromedary immunized against DARC N-terminal extracellular domain and selected for DARC binding. A described VHH, CA52, does recognize native DARC on cells. It inhibits P. vivax invasion of erythrocytes and displaces interleukin-8 bound to DARC. The targeted epitope overlaps the well-defined DARC Fy6 epitope. K (D) of CA52-DARC equilibrium is sub-nanomolar, hence ideal to develop diagnostic or therapeutic compounds. Immunocapture by immobilized CA52 yielded highly purified DARC from engineered K562 cells. This first report on a VHH with specificity for a red blood cell protein exemplifies VHHs' potentialities to target, to purify, and to modulate the function of cellular markers.

  11. Ovarian carcinoma glyco-antigen targeted by human IgM antibody.

    Directory of Open Access Journals (Sweden)

    Yi Chen

    Full Text Available Epithelial Ovarian Cancer (EOC cells expression of a novel carbohydrate antigen was defined using a human VH4-34 encoded IgM monoclonal antibody (mAb216. MAb216 binds to a poly N-acetyllactosamine epitope expressed on B cells and kills normal and malignant B cells in vitro and in vivo. EOC patient ascites and EOC cell lines were used to study the anti tumor effect of mAb216. Various assays were used to characterize the epitope and demonstrate antibody-mediated binding and cytotoxicity in EOC. Drug and antibody combination effects were determined by calculating the combination index values using the Chou and Talalay method. MAb216 displays direct antibody mediated cytotoxicity on a population of human EOC tumor and ascites samples and EOC cell lines, which express high amounts of poly N-acetyllactosamine epitope, carried by CD147/CD98. Eighty four percent of patient samples, including platin resistant, had a tumor population that bound the monoclonal antibody. The binding pattern of mAb216 and mechanism of cytotoxicity was similar to that seen on normal and malignant B cells with unique general membrane disruption and "pore" formation. In vitro incubation with mAb216 and cisplatin enhanced killing of OVCAR3 cell line. In EOC cell lines percent cytotoxicity correlated with percent expression of epitope. Although in vitro data shows specific EOC cytotoxicity, for possible treatment of EOC MAb216 would need to be evaluated in a clinical trial with or without chemotherapy.

  12. Spleen vagal denervation inhibits the production of antibodies to circulating antigens.

    Directory of Open Access Journals (Sweden)

    Ruud M Buijs

    Full Text Available BACKGROUND: Recently the vagal output of the central nervous system has been shown to suppress the innate immune defense to pathogens. Here we investigated by anatomical and physiological techniques the communication of the brain with the spleen and provided evidence that the brain has the capacity to stimulate the production of antigen specific antibodies by its parasympathetic autonomic output. METHODOLOGY/PRINCIPAL FINDINGS: This conclusion was reached by successively demonstrating that: 1. The spleen receives not only sympathetic input but also parasympathetic input. 2. Intravenous trinitrophenyl-ovalbumin (TNP-OVA does not activate the brain and does not induce an immune response. 3. Intravenous TNP-OVA with an inducer of inflammation; lipopolysaccharide (LPS, activates the brain and induces TNP-specific IgM. 4. LPS activated neurons are in the same areas of the brain as those that provide parasympathetic autonomic information to the spleen, suggesting a feed back circuit between brain and immune system. Consequently we investigated the interaction of the brain with the spleen and observed that specific parasympathetic denervation but not sympathetic denervation of the spleen eliminates the LPS-induced antibody response to TNP-OVA. CONCLUSIONS/SIGNIFICANCE: These findings not only show that the brain can stimulate antibody production by its autonomic output, it also suggests that the power of LPS as adjuvant to stimulate antibody production may also depend on its capacity to activate the brain. The role of the autonomic nervous system in the stimulation of the adaptive immune response may explain why mood and sleep have an influence on antibody production.

  13. Leaky RAG Deficiency in Adult Patients with Impaired Antibody Production against Bacterial Polysaccharide Antigens.

    Directory of Open Access Journals (Sweden)

    Christoph B Geier

    Full Text Available Loss of function mutations in the recombination activating genes RAG1 and RAG2 have been reported to cause a T-B-NK+ type of severe combined immunodeficiency. In addition identification of hypomorphic mutations in RAG1 and RAG2 has led to an expansion of the spectrum of disease to include Omenn syndrome, early onset autoimmunity, granuloma, chronic cytomegalovirus- or EBV-infection with expansion of gamma/delta T-cells, idiophatic CD4 lymphopenia and a phenotype resembling common variable immunodeficiency. Herein we describe a novel presentation of leaky RAG1 and RAG2 deficiency in two unrelated adult patients with impaired antibody production against bacterial polysaccharide antigens. Clinical manifestation included recurrent pneumonia, sinusitis, otitis media and in one patient recurrent cutaneous vasculitis. Both patients harbored a combination of a null mutation on one allele with a novel hypomorphic RAG1/2 mutation on the other allele. One of these novel mutations affected the start codon of RAG1 and resulted in an aberrant gene and protein expression. The second novel RAG2 mutation leads to a truncated RAG2 protein, lacking the C-terminus with intact core RAG2 and reduced VDJ recombination capacity as previously described in a mouse model. Both patients presented with severely decreased numbers of naïve CD4+ T cells and defective T independent IgG responses to bacterial polysaccharide antigens, while T cell-dependent IgG antibody formation e.g. after tetanus or TBEV vaccination was intact. In conclusion, hypomorphic mutations in genes responsible for SCID should be considered in adults with predominantly antibody deficiency.

  14. Enhanced acquired antibodies to a chimeric Plasmodium falciparum antigen; UB05-09 is associated with protective immunity against malaria.

    Science.gov (United States)

    Dinga, J N; Gamua, S D; Titanji, V P K

    2017-08-01

    It has been shown that covalently linking two antigens could enhance the immunogenicity of the chimeric construct. To prioritize such a chimera for malaria vaccine development, it is necessary to demonstrate that naturally acquired antibodies against the chimera are associated with protection from malaria. Here, we probe the ability of a chimeric construct of UB05 and UB09 antigens (UB05-09) to better differentiate between acquired immune protection and susceptibility to malaria. In a cross-sectional study, recombinant UB05-09 chimera and the constituent antigens were used to probe for specific antibodies in the plasma from children and adults resident in a malaria-endemic zone, using the enzyme-linked immunosorbent assay (ELISA). Anti-UB05-09 antibody levels doubled that of its constituent antigens, UB09 and UB05, and this correlated with protection against malaria. The presence of enhanced UB05-09-specific antibody correlated with the absence of fever and parasitaemia, which are the main symptoms of malaria infection. The chimera is more effective in detecting and distinguishing acquired protective immunity against malaria than any of its constituents taken alone. Online B-cell epitope prediction tools confirmed the presence of B-cell epitopes in the study antigens. UB05-09 chimera is a marker of protective immunity against malaria that needs to be studied further. © 2017 John Wiley & Sons Ltd.

  15. An analytical approach to reduce between-plate variation in multiplex assays that measure antibodies to Plasmodium falciparum antigens.

    Science.gov (United States)

    Fang, Rui; Wey, Andrew; Bobbili, Naveen K; Leke, Rose F G; Taylor, Diane Wallace; Chen, John J

    2017-07-17

    Antibodies play an important role in immunity to malaria. Recent studies show that antibodies to multiple antigens, as well as, the overall breadth of the response are associated with protection from malaria. Yet, the variability and reliability of antibody measurements against a combination of malarial antigens using multiplex assays have not been well characterized. A normalization procedure for reducing between-plate variation using replicates of pooled positive and negative controls was investigated. Sixty test samples (30 from malaria-positive and 30 malaria-negative individuals), together with five pooled positive-controls and two pooled negative-controls, were screened for antibody levels to 9 malarial antigens, including merozoite antigens (AMA1, EBA175, MSP1, MSP2, MSP3, MSP11, Pf41), sporozoite CSP, and pregnancy-associated VAR2CSA. The antibody levels were measured in triplicate on each of 3 plates, and the experiments were replicated on two different days by the same technician. The performance of the proposed normalization procedure was evaluated with the pooled controls for the test samples on both the linear and natural-log scales. Compared with data on the linear scale, the natural-log transformed data were less skewed and reduced the mean-variance relationship. The proposed normalization procedure using pooled controls on the natural-log scale significantly reduced between-plate variation. For malaria-related research that measure antibodies to multiple antigens with multiplex assays, the natural-log transformation is recommended for data analysis and use of the normalization procedure with multiple pooled controls can improve the precision of antibody measurements.

  16. Antibodies to variable Plasmodium falciparum-infected erythrocyte surface antigens are associated with protection from novel malaria infections

    DEFF Research Database (Denmark)

    Giha, H A; Staalsoe, T; Dodoo, D

    2000-01-01

    is maintained at low densities. Here, we test the hypothesis that the presence or absence of antibodies against variant antigens on the surface of P. falciparum-infected erythrocytes protect individuals against some infectious challenges and render them susceptible to others. Plasma collected in Daraweesh...... susceptible and protected individuals. Together, the results indicate that pre-existing anti-PfEMP1 antibodies can reduce the risk of contracting clinical malaria when challenged by novel parasite clones expressing homologous, but not heterologous variable surface antigens. The results also confirm...

  17. Evaluation of antigen and antibody ELISA's for epidemiological surveys of tsetse-transmitted trypanosomosis in cattle

    International Nuclear Information System (INIS)

    Eisler, M.C.; Hopkins, J.S.; Machila, N.; Bossche, P. van den; Peregrine, A.S.; Luckins, A.G.

    2000-01-01

    Sensitivity and specificity of the FAO/IAEA antigen-detection enzyme-linked immunosorbent assay (ELISA) kits for diagnosis of bovine trypanosomosis were investigated using sera from experimental cattle infected by tsetse challenge with cloned populations of Trypanosoma congolense (3 populations) or T. vivax (1 population). The kits are based on monoclonal antibodies that recognise internal antigens of tsetse-transmitted trypanosomes. Ten cattle were infected with each trypanosome population for at least 60 days, and in combination with uninfected cohorts (n=16) were used in a double-blind study design. Sensitivity and specificity of the tests depended on the choice of positive-negative thresholds expressed as percent positivity with respect to the median OD of 4 replicates of the strong positive reference serum provided with the kit. In general, while overall specificities were high, sensitivities of the antigen-ELISA's were poor. For example, at a cut-off of 5% positivity, the sensitivities of the antigen-ELISA's were 11% for samples (n=1162) from T. congolense infected cattle (n=30), and 24% for samples (n=283) from T. vivax infected cattle (n=10). The corresponding specificity values were 95% and 79%, respectively. There were no values of the positive-negative threshold at which both sensitivity and specificity were satisfactory. Trypanosome species-specificities of the antigen-ELISA's were also poor. Sensitivity and species-specificity of the antigen-ELISA for T. brucei infections were not investigated. The indirect ELISA for the detection of anti-trypanosomal antibodies in bovine serum was adapted for use with dried blood spots on filter paper, and standardised using a strong positive reference serum and the percent positivity system of data expression. The antibody-ELISA was evaluated in Zambia for use in epidemiological surveys of the prevalence of tsetse-transmitted bovine trypanosomosis. Known negative samples (sera, n=209; blood spots, n=466) were

  18. Enzyme-labeled Antigen Method: Development and Application of the Novel Approach for Identifying Plasma Cells Locally Producing Disease-specific Antibodies in Inflammatory Lesions

    International Nuclear Information System (INIS)

    Mizutani, Yasuyoshi; Shiogama, Kazuya; Onouchi, Takanori; Sakurai, Kouhei; Inada, Ken-ichi; Tsutsumi, Yutaka

    2016-01-01

    In chronic inflammatory lesions of autoimmune and infectious diseases, plasma cells are frequently observed. Antigens recognized by antibodies produced by the plasma cells mostly remain unclear. A new technique identifying these corresponding antigens may give us a breakthrough for understanding the disease from a pathophysiological viewpoint, simply because the immunocytes are seen within the lesion. We have developed an enzyme-labeled antigen method for microscopic identification of the antigen recognized by specific antibodies locally produced in plasma cells in inflammatory lesions. Firstly, target biotinylated antigens were constructed by the wheat germ cell-free protein synthesis system or through chemical biotinylation. Next, proteins reactive to antibodies in tissue extracts were screened and antibody titers were evaluated by the AlphaScreen method. Finally, with the enzyme-labeled antigen method using the biotinylated antigens as probes, plasma cells producing specific antibodies were microscopically localized in fixed frozen sections. Our novel approach visualized tissue plasma cells that produced 1) autoantibodies in rheumatoid arthritis, 2) antibodies against major antigens of Porphyromonas gingivalis in periodontitis or radicular cyst, and 3) antibodies against a carbohydrate antigen, Strep A, of Streptococcus pyogenes in recurrent tonsillitis. Evaluation of local specific antibody responses expectedly contributes to clarifying previously unknown processes in inflammatory disorders

  19. Screening for epitope specificity directly on culture supernatants in the early phase of monoclonal antibody production by an ELISA with biotin-labeled antigen.

    Science.gov (United States)

    Andersen, Ditte C; Jensen, Charlotte H; Gregersen, Annemette; Brandt, Jette; Kliem, Anette; Skjødt, Karsten; Koch, Claus; Teisner, Børge

    2004-01-01

    This report describes an assay for comparison of epitope specificity in groups of monoclonal antibodies against a given antigen. The only prerequisite is the biotin-labeled antigen. One of the monoclonal antibodies is captured onto a plastic surface via a rabbit anti-mouse Ig, and the other preincubated with biotinylated antigen. When the two antibodies react with the same epitope subsequent binding of the biotin-labeled antigen is abolished (inhibition). In the cases where no inhibition was observed, the two antibodies were considered to react with distinct, independent epitopes. The obvious advantages using this assay, are that it can be performed directly on culture supernatants in the early phase of monoclonal antibody production, and also works for antigens with repetitive epitopes. Moreover, the bonus effect, i.e., a signal in excess of the reference signal when sets of monoclonal antibodies with different epitope specificity are compared, gives a relative measure of affinity.

  20. Autologous monoclonal antibodies recognize tumour-associated antigens in X-irradiated C57BL/6 mice

    Energy Technology Data Exchange (ETDEWEB)

    Artus, A; Guillemain, B; Legrand, E; Astier-Gin, T; Mamoun, R; Duplan, J -F

    1986-09-01

    X-irradiation of C57BL/6 mice induces thymic lymphosarcomas which sometimes contain retroviruses which upon injection into normal mice mimic the effect of the irradiation. We examined whether specific antigenicities, viral or cellular, were expressed by tumour cells that could be recognized by antibodies from the irradiated animals. We developed monoclonal antibodies (MAbs) using splenocytes of the diseased animal. The reactivity of such MAbs towards thymoma cell lines established in vitro was investigated by means of an ELISA. At least 10 antibody specificities were detected on the 13 tumours investigated, allowing separation of the MAbs into three classes: (i) those recognizing the autologous tumour, heterologous tumours as well as normal thymic tissue, (ii) those specific for the autologous tumour, and (iii) those specific for one tumour, but not ones of autologous origin. The last two classes corresponded to specific tumour-associated antigens. Our panel of MAbs defined each tumour by the particular pattern of antigens harboured. It is striking that most of the antigens were present in the normal thymus and that only two tumours had additional antigenicities. Additionally, quantitative variations were observed in the levels of expression of these antigens.

  1. Bovine cysticercosis situation in Brazil

    Directory of Open Access Journals (Sweden)

    Gabriel Augusto Marques Rossi

    2014-02-01

    Full Text Available The taeniasis-cysticercosis complex is a long known zoonotic parasitosis characteristic of underdeveloped countries. In addition to its public health significance, this parasitosis is cause of economic losses to the beef production chain, and synonymous of technical inadequacy in relation to the adoption of Good Agricultural Practices. The occurrences of both human teniasis and bovine cysticercosis could and should be controlled with basic sanitary measures. However, there is much variation in the occurrence of the disease in cattle, characterizing a low rate of technical development as well as problems related to the adoption of basic sanitation measures. This review describes, in details, the causative agent and its epidemiological chain, besides raising current information about the occurrence of bovine cysticercosis in different regions of Brazil, aiming at the adoption of prophylactic measures by different segments responsible.

  2. Seroprevalence of human cysticercosis in Jataí, Goiás state, Brazil

    Directory of Open Access Journals (Sweden)

    Kaliny Xavier da Guarda

    2018-03-01

    Full Text Available The Taenia solium cysticercosis affects millions of people worldwide and is considered a public health problem, especially in developing countries. The diagnosis of neurocysticercosis is complex and involves the analysis of epidemiological, clinical, neuroimaging, and immunological host data. Neurocysticercosis is endemic in Brazil, and is related to the cause of death mainly in the Southeast, South, and Central-West regions. The objective of this study was to determine the seroprevalence of cysticercosis in inhabitants of the city of Jataí, Goiás, in the Central-West region of Brazil from April to August 2012. A total of 529 serum samples were analyzed by enzyme-linked immunosorbent assay for detecting IgG antibodies against T. solium larvae, and Western blotting was used for confirming the diagnosis through the recognition of at least two specific peptides from their serum antibodies. The 351/529 (66.3% reactive samples were analyzed by enzyme-linked immunosorbent assay and Western blotting confirmed the diagnosis in 73 samples that recognized at least two of the following peptides specific IgG antibodies for cysticercosis: 18, 24, 28–32, 39–42, 47–52, 64–68, and 70 kDa. The seroprevalence of cysticercosis was 13.8% (95% CI 5.9–21.7, demonstrating that the studied area is endemic to this disease. Keywords: Cysticercosis, Taenia solium, Epidemiology, Diagnosis, Brazil

  3. Exposure to the Epstein–Barr Viral Antigen Latent Membrane Protein 1 Induces Myelin-Reactive Antibodies In Vivo

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    Yakov Lomakin

    2017-07-01

    Full Text Available Multiple sclerosis (MS is an autoimmune chronic inflammatory disease of the central nervous system (CNS. Cross-reactivity of neuronal proteins with exogenous antigens is considered one of the possible mechanisms of MS triggering. Previously, we showed that monoclonal myelin basic protein (MBP-specific antibodies from MS patients cross-react with Epstein–Barr virus (EBV latent membrane protein 1 (LMP1. In this study, we report that exposure of mice to LMP1 results in induction of myelin-reactive autoantibodies in vivo. We posit that chronic exposure or multiple acute exposures to viral antigen may redirect B cells from production of antiviral antibodies to antibodies, specific to myelin antigen. However, even in inbred animals, which are almost identical in terms of their genomes, such an effect is only observed in 20–50% of animals, indicating that this change occurs by chance, rather than systematically. Cross-immunoprecipitation analysis showed that only part of anti-MBP antibodies from LMP1-immunized mice might simultaneously bind LMP1. In contrast, the majority of anti-LMP1 antibodies from MBP-immunized mice bind MBP. De novo sequencing of anti-LMP1 and anti-MBP antibodies by mass spectrometry demonstrated enhanced clonal diversity in LMP1-immunized mice in comparison with MBP-immunized mice. We suggest that induction of MBP-reactive antibodies in LMP1-immunized mice may be caused by either Follicular dendritic cells (FDCs or by T cells that are primed by myelin antigens directly in CNS. Our findings help to elucidate the still enigmatic link between EBV infection and MS development, suggesting that myelin-reactive antibodies raised as a response toward EBV protein LMP1 are not truly cross-reactive but are primarily caused by epitope spreading.

  4. Exposure to the Epstein–Barr Viral Antigen Latent Membrane Protein 1 Induces Myelin-Reactive Antibodies In Vivo

    Science.gov (United States)

    Lomakin, Yakov; Arapidi, Georgii Pavlovich; Chernov, Alexander; Ziganshin, Rustam; Tcyganov, Evgenii; Lyadova, Irina; Butenko, Ivan Olegovich; Osetrova, Maria; Ponomarenko, Natalia; Telegin, Georgy; Govorun, Vadim Markovich; Gabibov, Alexander; Belogurov, Alexey

    2017-01-01

    Multiple sclerosis (MS) is an autoimmune chronic inflammatory disease of the central nervous system (CNS). Cross-reactivity of neuronal proteins with exogenous antigens is considered one of the possible mechanisms of MS triggering. Previously, we showed that monoclonal myelin basic protein (MBP)-specific antibodies from MS patients cross-react with Epstein–Barr virus (EBV) latent membrane protein 1 (LMP1). In this study, we report that exposure of mice to LMP1 results in induction of myelin-reactive autoantibodies in vivo. We posit that chronic exposure or multiple acute exposures to viral antigen may redirect B cells from production of antiviral antibodies to antibodies, specific to myelin antigen. However, even in inbred animals, which are almost identical in terms of their genomes, such an effect is only observed in 20–50% of animals, indicating that this change occurs by chance, rather than systematically. Cross-immunoprecipitation analysis showed that only part of anti-MBP antibodies from LMP1-immunized mice might simultaneously bind LMP1. In contrast, the majority of anti-LMP1 antibodies from MBP-immunized mice bind MBP. De novo sequencing of anti-LMP1 and anti-MBP antibodies by mass spectrometry demonstrated enhanced clonal diversity in LMP1-immunized mice in comparison with MBP-immunized mice. We suggest that induction of MBP-reactive antibodies in LMP1-immunized mice may be caused by either Follicular dendritic cells (FDCs) or by T cells that are primed by myelin antigens directly in CNS. Our findings help to elucidate the still enigmatic link between EBV infection and MS development, suggesting that myelin-reactive antibodies raised as a response toward EBV protein LMP1 are not truly cross-reactive but are primarily caused by epitope spreading. PMID:28729867

  5. Exposure to the Epstein-Barr Viral Antigen Latent Membrane Protein 1 Induces Myelin-Reactive Antibodies In Vivo.

    Science.gov (United States)

    Lomakin, Yakov; Arapidi, Georgii Pavlovich; Chernov, Alexander; Ziganshin, Rustam; Tcyganov, Evgenii; Lyadova, Irina; Butenko, Ivan Olegovich; Osetrova, Maria; Ponomarenko, Natalia; Telegin, Georgy; Govorun, Vadim Markovich; Gabibov, Alexander; Belogurov, Alexey

    2017-01-01

    Multiple sclerosis (MS) is an autoimmune chronic inflammatory disease of the central nervous system (CNS). Cross-reactivity of neuronal proteins with exogenous antigens is considered one of the possible mechanisms of MS triggering. Previously, we showed that monoclonal myelin basic protein (MBP)-specific antibodies from MS patients cross-react with Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1). In this study, we report that exposure of mice to LMP1 results in induction of myelin-reactive autoantibodies in vivo . We posit that chronic exposure or multiple acute exposures to viral antigen may redirect B cells from production of antiviral antibodies to antibodies, specific to myelin antigen. However, even in inbred animals, which are almost identical in terms of their genomes, such an effect is only observed in 20-50% of animals, indicating that this change occurs by chance, rather than systematically. Cross-immunoprecipitation analysis showed that only part of anti-MBP antibodies from LMP1-immunized mice might simultaneously bind LMP1. In contrast, the majority of anti-LMP1 antibodies from MBP-immunized mice bind MBP. De novo sequencing of anti-LMP1 and anti-MBP antibodies by mass spectrometry demonstrated enhanced clonal diversity in LMP1-immunized mice in comparison with MBP-immunized mice. We suggest that induction of MBP-reactive antibodies in LMP1-immunized mice may be caused by either Follicular dendritic cells (FDCs) or by T cells that are primed by myelin antigens directly in CNS. Our findings help to elucidate the still enigmatic link between EBV infection and MS development, suggesting that myelin-reactive antibodies raised as a response toward EBV protein LMP1 are not truly cross-reactive but are primarily caused by epitope spreading.

  6. Protection against Escherichia coli K1 infection in newborn rats by antibody to K1 capsular polysaccharide antigen.

    OpenAIRE

    Bortolussi, R; Ferrier, P

    1980-01-01

    The protective value of antibody to the K1 capsular polysaccharide antigen of Escherichia coli was investigated in a newborn rat model of E. coli K1 infection. Pregnant rats were immunized intravenously with E. coli, and the agglutinating titer to meningococcal group B polysaccharide, which is identical to K1 polysaccharide, was measured in the serum of rats and their offspring. Convalescent serum from rat mothers showed an increased antibody titer in animals injected twice but not once with ...

  7. Affinity improvement of a therapeutic antibody by structure-based computational design: generation of electrostatic interactions in the transition state stabilizes the antibody-antigen complex.

    Directory of Open Access Journals (Sweden)

    Masato Kiyoshi

    Full Text Available The optimization of antibodies is a desirable goal towards the development of better therapeutic strategies. The antibody 11K2 was previously developed as a therapeutic tool for inflammatory diseases, and displays very high affinity (4.6 pM for its antigen the chemokine MCP-1 (monocyte chemo-attractant protein-1. We have employed a virtual library of mutations of 11K2 to identify antibody variants of potentially higher affinity, and to establish benchmarks in the engineering of a mature therapeutic antibody. The most promising candidates identified in the virtual screening were examined by surface plasmon resonance to validate the computational predictions, and to characterize their binding affinity and key thermodynamic properties in detail. Only mutations in the light-chain of the antibody are effective at enhancing its affinity for the antigen in vitro, suggesting that the interaction surface of the heavy-chain (dominated by the hot-spot residue Phe101 is not amenable to optimization. The single-mutation with the highest affinity is L-N31R (4.6-fold higher affinity than wild-type antibody. Importantly, all the single-mutations showing increase affinity incorporate a charged residue (Arg, Asp, or Glu. The characterization of the relevant thermodynamic parameters clarifies the energetic mechanism. Essentially, the formation of new electrostatic interactions early in the binding reaction coordinate (transition state or earlier benefits the durability of the antibody-antigen complex. The combination of in silico calculations and thermodynamic analysis is an effective strategy to improve the affinity of a matured therapeutic antibody.

  8. ELISA test for the diagnosis of cysticercosis in pigs using antigens of Taenia solium and Taenia crassiceps cysticerci Teste ELISA para diagnóstico da cisticercose suína usando antígenos de larvas de Taenia solium e Taenia crassiceps

    Directory of Open Access Journals (Sweden)

    Paulo Sérgio de Arruda PINTO

    2000-04-01

    Full Text Available In the present study ELISA was standardized for the diagnosis of swine cysticercosis based on necropsy parameters and confirmed positive and negative control sera. Serum samples from pigs with other infections were also assayed to determine possible cross-reactions. Four antigens were assayed: from Taenia crassiceps vesicular fluid (VF-Tcra and crude larvae extract (T-Tcra, and from Taenia solium extracts of scolex (S-Ts and of larvae (T-Ts. A checkerboard evaluation of antigen, serum and conjugate dilutions, as well as the use of Tween-20 and skim cow milk in wash and blocking solution had a marked effect on improving ELISA performance. All the antigens showed a good performance, but VF-Tcra was the best, with 96.0% and 80.0% sensitivities for cut-offs respectively at 2sd and 3sd, and corresponding specificities of 97.5% and 100.0%. Cross-reactivity was observed only with hydatidosis and ascaridiosis. In view of the high performance observed, the ELISA test should be recommended for the diagnosis of cysticercosis in suspected swine in slaughterhouses and for the screening of cysticercosis in swine production. These results will support integrated measures of cysticercosis control throughout the chain of swine production, effectively contributing to public health.Foi padronizado o teste ELISA para o diagnóstico da cisticercose suína. Após confirmação por exame post-mortem, os soros dos respectivos animais foram empregados como controles positivos e negativos. Soros de suínos portadores de infecções heterólogas foram ensaiados para determinação de reações cruzadas. Os quatro antígenos testados na fase de padronização foram líquido vesicular (VF e extrato total (T de larvas de Taenia crassiceps (Tcra e de extrato de escólex (S e de cisticercos (T de Taenia solium (Tso. A titulação em bloco das ótimas concentrações de antígenos e diluições de soros e de conjugado, bem como o emprego de Tween-20 e de leite desnatado nas

  9. Seizures, cysticercosis and rural-to-urban migration: the PERU MIGRANT study.

    Science.gov (United States)

    Gonzales, Isidro; Miranda, J Jaime; Rodriguez, Silvia; Vargas, Victor; Cjuno, Alfredo; Smeeth, Liam; Gonzalez, Armando E; Tsang, Victor C W; Gilman, Robert H; Garcia, Hector H

    2015-04-01

    To examine the prevalence of seizures, epilepsy and seropositivity to cysticercosis in rural villagers (cysticercosis-endemic setting), rural-to-urban migrants into a non-endemic urban shanty town and urban inhabitants of the same non-endemic shanty town. Three Peruvian populations (n = 985) originally recruited into a study about chronic diseases and migration were studied. These groups included rural inhabitants from an endemic region (n = 200), long-term rural-to-urban migrants (n = 589) and individuals living in the same urban setting (n = 196). Seizure disorders were detected by a survey, and a neurologist examined positive respondents. Serum samples from 981/985 individuals were processed for cysticercosis antibodies on immunoblot. Epilepsy prevalence (per 1000 people) was 15.3 in the urban group, 35.6 in migrants and 25 in rural inhabitants. A gradient in cysticercosis antibody seroprevalence was observed: urban 2%, migrant 13.5% and rural group 18% (P < 0.05). A similarly increasing pattern of higher seroprevalence was observed among migrants by age at migration. In rural villagers, there was strong evidence of an association between positive serology and having seizures (P = 0.011) but such an association was not observed in long-term migrants or in urban residents. In the entire study population, compared with seronegative participants, those with strong antibody reactions (≥ 4 antibody bands) were more likely to have epilepsy (P < 0.001). It is not only international migration that affects cysticercosis endemicity; internal migration can also affect patterns of endemicity within an endemic country. The neurological consequences of cysticercosis infection likely outlast the antibody response for years after rural-to-urban migration. © 2015 The Authors. Tropical Medicine & International Health Published by John Wiley & Sons Ltd.

  10. Prevalence of Diego blood group antigen and the antibody in three ethnic population groups in Klang valley of Malaysia

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    Cheong Tar Wei

    2013-01-01

    Full Text Available Background: Diego blood group antigen, Di(a, is very rare among Caucasians and Blacks, but relatively common among the South American Indians and Asians of Mongolian origin. The antibody to Di(a is clinically significant to cause hemolytic disease in a new-born or hemolytic transfusion reaction. Objectives: This study was designed to determine the prevalence of Di(a antigen among the blood donors from the three major ethnic groups in Klang Valley of Malaysia as well as to find an incidence of an antibody of the Diego antigen, anti-Di(a, in a tertiary care hospital to ascertain the need to include Di(a+ red cells for an antibody screen cell panel. Materials and Methods: Serological tests were performed by column agglutination technique using commercial reagents and following instruction as per kit insert. Results: Di(a antigen was found with a frequency of 2.1% among the Malaysians donors in three ethnic groups viz, Malay, Chinese and Indian. It was present among 1.25% of 401 Malay, 4.01% of Chinese and 0.88% of 114 Indian origin donors. None of the 1442 patients, including 703 antenatal outpatients, had anti-Di(a in serum. Conclusion: The prevalence of Di(a antigen was found among the donors of all the three ethnic background with varying frequency. Inclusion of Di(a+ red cells in routine antibody screening program would certainly help in detection of this clinically significant antibody and to provide safe blood transfusion in the Klang Valley, though the incidence of antibody appears to be very low in the region.

  11. Prevalence of Diego blood group antigen and the antibody in three ethnic population groups in Klang valley of Malaysia.

    Science.gov (United States)

    Wei, Cheong Tar; Al-Hassan, Faisal Muti; Naim, Norris; Knight, Aishah; Joshi, Sanmukh R

    2013-01-01

    Diego blood group antigen, Di(a), is very rare among Caucasians and Blacks, but relatively common among the South American Indians and Asians of Mongolian origin. The antibody to Di(a) is clinically significant to cause hemolytic disease in a new-born or hemolytic transfusion reaction. This study was designed to determine the prevalence of Di(a) antigen among the blood donors from the three major ethnic groups in Klang Valley of Malaysia as well as to find an incidence of an antibody of the Diego antigen, anti-Di(a), in a tertiary care hospital to ascertain the need to include Di(a+) red cells for an antibody screen cell panel. Serological tests were performed by column agglutination technique using commercial reagents and following instruction as per kit insert. Di(a) antigen was found with a frequency of 2.1% among the Malaysians donors in three ethnic groups viz, Malay, Chinese and Indian. It was present among 1.25% of 401 Malay, 4.01% of Chinese and 0.88% of 114 Indian origin donors. None of the 1442 patients, including 703 antenatal outpatients, had anti-Di(a) in serum. The prevalence of Di(a) antigen was found among the donors of all the three ethnic background with varying frequency. Inclusion of Di(a+) red cells in routine antibody screening program would certainly help in detection of this clinically significant antibody and to provide safe blood transfusion in the Klang Valley, though the incidence of antibody appears to be very low in the region.

  12. Autoimmune hepatitis-specific antibodies against soluble liver antigen and liver cytosol type 1 in patients with chronic viral hepatitis

    OpenAIRE

    Rigopoulou, Eirini I; Mytilinaiou, Maria; Romanidou, Ourania; Liaskos, Christos; Dalekos, George N

    2007-01-01

    Background Non-organ specific autoantibodies are highly prevalent in patients with chronic hepatitis C (HCV). Among them, anti-liver kidney microsomal type 1 (LKM1) antibody – the serological marker of type 2 autoimmune hepatitis (AIH-2)- is detected in up to 11% of the HCV-infected subjects. On the other hand, anti-liver cytosol type 1 antibodies (anti-LC1) – either in association with anti-LKM1, or in isolation- and anti-soluble liver antigen antibodies (anti-SLA) have been considered as us...

  13. High prevalence of HIV p24 antigen among HIV antibody negative prospective blood donors in Ile-Ife, Nigeria.

    Science.gov (United States)

    Japhet, Margaret Oluwatoyin; Adewumi, Moses Olubusuyi; Adesina, Olufisayo Adeyemi; Donbraye, Emmanuel

    2016-01-01

    Blood transfusion service centers in Nigeria screen donated blood for markers of HIV infection using antibody- (Ab) based rapid test and in some centers, positives are re-tested using Ab-based ELISA. Paucity of data exists on p24 antigen prevalence among HIV Ab-negative donors in Nigeria. This study aims at detecting HIV p24 antigen among prospective blood donors in Osun State, Nigeria. Prospective blood donors negative for HIV antibodies using Determine test kit were re-tested using BIORAD GENSCREEN Ultra Ag-Ab ELISA kit, a fourth-generation ELISA kit that detects HIV antibodies/p24 antigen. Of the 169 HIV Ab-negative prospective donors, 10 (5.9%) were positive for HIV p24 antigen and 70% (7/10) of them were in the age range 18-30 years. Results of this study show that blood transfusion is still one of the major routes of HIV transmission in Nigeria and a higher proportion is among youth. Inclusion of p24 antigen testing into the blood donor screening will help reduce transfusion associated HIV in Nigeria if Nucleic Acid Testing (NAT) of all blood donor samples is not affordable; also, HIV enlightenment programs tailored toward youth may help reduce this rate among donors since more young people donate blood in low/middle-income countries than in high-income countries.

  14. Glycosphingolipid antigens from Leishmania (L. amazonensis amastigotes: Binding of anti-glycosphingolipid monoclonal antibodies in vitro and in vivo

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    A.H. Straus

    1997-03-01

    Full Text Available Specific glycosphingolipid antigens of Leishmania (L. amazonensis amastigotes reactive with the monoclonal antibodies (MoAbs ST-3, ST-4 and ST-5 were isolated, and their structure was partially elucidated by negative ion fast atom bombardment mass spectrometry. The glycan moieties of five antigens presented linear sequences of hexoses and N-acetylhexosamines ranging from four to six sugar residues, and the ceramide moieties were found to be composed by a sphingosine d18:1 and fatty acids 24:1 or 16:0. Affinities of the three monoclonal antibodies to amastigote glycosphingolipid antigens were also analyzed by ELISA. MoAb ST-3 reacted equally well with all glycosphingolipid antigens tested, whereas ST-4 and ST-5 presented higher affinities to glycosphingolipids with longer carbohydrate chains, with five or more sugar units (slow migrating bands on HPTLC. Macrophages isolated from footpad lesions of BALB/c mice infected with Leishmania (L. amazonensis were incubated with MoAb ST-3 and, by indirect immunofluorescence, labeling was only detected on the parasite, whereas no fluorescence was observed on the surface of the infected macrophages, indicating that these glycosphingolipid antigens are not acquired from the host cell but synthesized by the amastigote. Intravenous administration of 125I-labeled ST-3 antibody to infected BALB/c mice showed that MoAb ST-3 accumulated significantly in the footpad lesions in comparison to blood and other tissues

  15. Antigenicity of envelop and non-structural proteins of dengue serotypes and their potentiality to elicit specifi antibody

    Directory of Open Access Journals (Sweden)

    Ramesh Venkatachalam

    2015-06-01

    Full Text Available Objective: To find out the antigenic nature of envelop (E and non-structural (NS proteins and their ability to induce specific antibodies, and to investigate specific antibody produced by specific dengue virus (DENV serotypes. Methods: Amino acid sequences of E and NS proteins of dengue serotypes were analysed by using VaxiJen antigen predicition server. The transmembrane of topology analyses were conducted by using transmembrane prediction using hidden markov models. The Hex dock server was used for docking. Results: The antigenicity score and exomembrane potentiality of E and NS proteins were calculated. All those proteins were antigenic; these antigens were made to interact with antibodies such as immunoglobulin A, immunoglobulin G and immunoglobulin M. Higher energy values of immunoglobulin M were found in DENV-1 and DENV-2, and more energy values were found in immunoglobulin G of DENV-3, DENV-4, NS-1, NS-3 and NS-5. Conclusions: In the present study, DENV-1 and DENV-2 are positive to immunoglobulin M and involved in the primary infection. DENV 3, DENV 4 and all the NS proteins (NS-1, NS-3, NS-5 which elicit immunoglobulin G are involved in the secondary infection.

  16. A new application of scanning electrochemical microscopy for the label-free interrogation of antibody-antigen interactions

    Energy Technology Data Exchange (ETDEWEB)

    Holmes, Joanne L.; Davis, Frank; Collyer, Stuart D. [Cranfield Health, Cranfield University, Cranfield, MK43 0AL (United Kingdom); Higson, Seamus P.J., E-mail: s.p.j.higson@cranfield.ac.uk [Cranfield Health, Cranfield University, Cranfield, MK43 0AL (United Kingdom)

    2011-03-18

    Within this work we present a 'proof of principle' study for the use of scanning electrochemical microscopy (SECM) to detect and image biomolecular interactions in a label-free assay as a potential alternative to current fluorescence techniques. Screen-printed carbon electrodes were used as the substrate for the deposition of a dotted array, where the dots consist of biotinylated polyethyleneimine. These were then further derivatised, first with neutravidin and then with a biotinylated antibody to the protein neuron specific enolase (NSE). SECM using a ferrocene carboxylic acid mediator showed clear differences between the array and the surrounding unmodified carbon. Imaging of the arrays before and following exposure to various concentrations of the antigen showed clear evidence for specific binding of the NSE antigen to the antibody derivatised dots. Non-specific binding was quantified. Control experiments with other proteins showed only non-specific binding across the whole of the substrate, thereby confirming that specific binding does occur between the antibody and antigen at the surface of the dots. Binding of the antigen was accompanied by a measured increase in current response, which may be explained in terms of protein electrostatic interaction and hydrophobic interactions to the mediator, thereby increasing the localised mediator flux. A calibration curve was obtained between 500 fg mL{sup -1} to 200 pg mL{sup -1} NSE which demonstrated a logarithmic relationship between the current change upon binding and antigen concentration without the need for any labelling of the substrate.

  17. 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

  18. The Effectiveness of Implementing an E-Book: Antigen and Antibody Reaction for Diagnosis of Diseases in Microbiology Learning

    Science.gov (United States)

    Samrejrongroj, Phakakrong; Boonsiri, Tanit; Thunyaharn, Sudaluck; Sangarun, Preeyapan

    2014-01-01

    Currently very few Thai Immunology e-Books are available online. The authors created an online e-Book titled, "Antigen and Antibody Reaction for Diagnosis of Diseases" and used a quasi experimental research design to assess the effectiveness of its implementation in terms of knowledge gained, written exam scores and student satisfaction.…

  19. A remote arene-binding site on prostate specific membrane antigen revealed by antibody-recruiting small molecules

    Czech Academy of Sciences Publication Activity Database

    Zhang, A.X.; Murelli, R.P.; Bařinka, Cyril; Michel, J.; Cocleaza, A.; Jorgensen, W.L.; Lubkowski, J.; Spiegel, D.A.

    2010-01-01

    Roč. 132, č. 36 (2010), s. 12711-12716 ISSN 0002-7863 Institutional research plan: CEZ:AV0Z50520701 Keywords : Prostate -specific membrane antigen * antibody recruiting molecules * Structure-activity relationship Subject RIV: CE - Biochemistry Impact factor: 9.019, year: 2010

  20. The molecular determinants of antibody recognition and antigenic drift in the H3 hemagglutinin of swine influenza A virus

    Science.gov (United States)

    Influenza A virus (IAV) of the H3 subtype is an important pathogen that affects both humans and swine. The main intervention strategy for preventing infection is vaccination to induce neutralizing antibodies against the surface glycoprotein hemagglutinin (HA). However, due to antigenic drift, vaccin...

  1. Involvement of lymphocyte function-associated antigen-1 (LFA-1) in HIV infection: inhibition by monoclonal antibody

    DEFF Research Database (Denmark)

    Hansen, J E; Nielsen, C; Mathiesen, Lars Reinhardt

    1991-01-01

    Monoclonal antibodies (MAbs) against the alpha- and beta-chain of lymphocyte-associated antigen-1 (LFA-1) were examined for inhibition of HIV-1 infection in vitro. Infection of the T cell line MT4 and the monocytic cell line U937 by isolates HTLVIIIB and SSI-002, respectively was inhibited...

  2. 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.

  3. Prevalence and risk factors for porcine cysticercosis in rural communities of eastern Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Emilio C. Acevedo-Nieto

    Full Text Available ABSTRACT: Cysticercosis is caused by Taenia solium, a parasitic zoonosis that affects human and pigs raised free-range in developing countries. The epidemiology of the taeniosis cysticercosis complex in Brazil is poorly understood especially when it comes to field research. The aim of this study was to estimate the prevalence and identify the risk factors associated with porcine cysticercosis in rural communities located in the east of Minas Gerais (MG, Brazil. From 371 farms in the county of Tumiritinga/MG, 101 farms from 14 communities were randomly sampled. Blood samples from pigs were collected, and epidemiological questionnaires were carried out. The serum samples obtained were analyzed through immunodiagnosis techniques, including ELISA and Western Blot, both for the detection of antibodies. The data obtained by different surveys were analyzed using EpiInfo 3.5.1 software to determine seroprevalence and risk factors associated with cysticercosis. The prevalence of farms with porcine cysticercosis was 9.9% (10/101 and antibody-based seropositive was 5.3% (13/247. The results indicate that cysticercosis occurs in high level in the rural area never studied before. These results suggest the presence of tapeworm carriers contributing to the occurrence and maintenance of this zoonotic life cycle in the county. Regarding risk factors, the most significant determinants for porcine cysticercosis in the field were free-range pig management (OR: 17.4, p: 0.0001, the method of disposal of human faeces in the environmental (OR: 7.6; p 0.012, and the size of the farm. Porcine cysticercosis was diagnosed only in areas represented by Agrarian Reform Settlements. From the results, it is possible to recommend as a means of control and prevention the destination of human faeces in appropriate sanitary landfills and the production of pigs in an enclosed area. Additionally, improving education in the communities sampled will indirectly affect the spreading of

  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. Antibody drug conjugates and bystander killing: is antigen-dependent internalisation required?

    Science.gov (United States)

    Staudacher, Alexander H; Brown, Michael P

    2017-12-05

    Antibody drug conjugates (ADCs) employ the exquisite specificity of tumour-specific monoclonal antibodies (mAb) for the targeted delivery of highly potent cytotoxic drugs to the tumour site. The chemistry of the linker, which connects the drug to the mAb, determines how and when the drug is released from the mAb. This, as well as the chemistry of the drug, can dictate whether the drug can diffuse into surrounding cells, resulting in 'bystander killing'. Initially, any bystander killing mechanism of action of an ADC was understood to involve an essential sequence of steps beginning with surface antigen targeting, internalisation, intracellular linker cleavage, drug release, and diffusion of drug away from the targeted cell. However, recent studies indicate that, depending on the linker and drug combination, this mechanism may not be essential and ADCs can be cleaved extracellularly or via other mechanisms. In this minireview, we will examine the role of bystander killing by ADCs and explore the emerging evidence of how this can occur independently of internalisation.

  6. 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)

  7. Uncommon presentation of neuro- cysticercosis

    African Journals Online (AJOL)

    Uncommon presentation of neuro- cysticercosis. Neurocysticercosis (NCC) is a common parasitic infection of the central nervous system caused by the pork tapeworm Taenia solium. The clinical presentation of NCC in children includes generalised and partial seizures with or without features of raised intracranial pressure.

  8. Carbon-13 NMR study of switch variant anti-dansyl antibodies: Antigen binding and domain-domain interactions

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Koichi; Matsunaga, Chigusa; Odaka, Asano; Yamato, Sumie; Takaha, Wakana; Shimada, Ichio; Arata, Yoji (Univ. of Tokyo (Japan))

    1991-07-02

    A {sup 13}C NMR study is reported of switch variant anti-dansyl antibodies, which possess the identical V{sub H}, V{sub L}, and C{sub L} domains in conjunction with highly homologous but not identical heavy-chain constant regions. Each of the antibodies has been selectively labeled with {sup 13}C at the carbonyl carbon of Trp, Tyr, His, or Cys residue by growing hybridoma cells in serum-free medium. Spectral assignments have been made by folowing the procedure described previously for the switch variant antibodies labeled with (1-{sup 13}C)Met. On the basis of the spectral data collected for the antibodies and their proteolytic fragments, the authors discuss how {sup 13}C NMR spectroscopy can be used for the structural analyses of antigen binding and also of domain-domain interactions in the antibody molecule.

  9. Carbon-13 NMR study of switch variant anti-dansyl antibodies: Antigen binding and domain-domain interactions

    International Nuclear Information System (INIS)

    Kato, Koichi; Matsunaga, Chigusa; Odaka, Asano; Yamato, Sumie; Takaha, Wakana; Shimada, Ichio; Arata, Yoji

    1991-01-01

    A 13 C NMR study is reported of switch variant anti-dansyl antibodies, which possess the identical V H , V L , and C L domains in conjunction with highly homologous but not identical heavy-chain constant regions. Each of the antibodies has been selectively labeled with 13 C at the carbonyl carbon of Trp, Tyr, His, or Cys residue by growing hybridoma cells in serum-free medium. Spectral assignments have been made by folowing the procedure described previously for the switch variant antibodies labeled with [1- 13 C]Met. On the basis of the spectral data collected for the antibodies and their proteolytic fragments, the authors discuss how 13 C NMR spectroscopy can be used for the structural analyses of antigen binding and also of domain-domain interactions in the antibody molecule

  10. Antigenic modulation limits the effector cell mechanisms employed by type I anti-CD20 monoclonal antibodies.

    Science.gov (United States)

    Tipton, Thomas R W; Roghanian, Ali; Oldham, Robert J; Carter, Matthew J; Cox, Kerry L; Mockridge, C Ian; French, Ruth R; Dahal, Lekh N; Duriez, Patrick J; Hargreaves, Philip G; Cragg, Mark S; Beers, Stephen A

    2015-03-19

    Following the success of rituximab, 2 other anti-CD20 monoclonal antibodies (mAbs), ofatumumab and obinutuzumab, have entered clinical use. Ofatumumab has enhanced capacity for complement-dependent cytotoxicity, whereas obinutuzumab, a type II mAb, lacks the ability to redistribute into lipid rafts and is glycoengineered for augmented antibody-dependent cellular cytotoxicity (ADCC). We previously showed that type I mAbs such as rituximab have a propensity to undergo enhanced antigenic modulation compared with type II. Here we assessed the key effector mechanisms affected, comparing type I and II antibodies of various isotypes in ADCC and antibody-dependent cellular-phagocytosis (ADCP) assays. Rituximab and ofatumumab depleted both normal and leukemic human CD20-expressing B cells in the mouse less effectively than glycoengineered and wild-type forms of obinutuzumab, particularly when human immunoglobulin G1 (hIgG1) mAbs were compared. In contrast to mouse IgG2a, hIgG1 mAbs were ineffective in ADCC assays with murine natural killer cells as effectors, whereas ADCP was equivalent for mouse IgG2a and hIgG1. However, rituximab's ability to elicit both ADCC and ADCP was reduced by antigenic modulation, whereas type II antibodies remained unaffected. These data demonstrate that ADCP and ADCC are impaired by antigenic modulation and that ADCP is the main effector function employed in vivo. © 2015 by The American Society of Hematology.

  11. Isolation and characterization of antigen-specific alpaca (Lama pacos) VHH antibodies by biopanning followed by high-throughput sequencing.

    Science.gov (United States)

    Miyazaki, Nobuo; Kiyose, Norihiko; Akazawa, Yoko; Takashima, Mizuki; Hagihara, Yosihisa; Inoue, Naokazu; Matsuda, Tomonari; Ogawa, Ryu; Inoue, Seiya; Ito, Yuji

    2015-09-01

    The antigen-binding domain of camelid dimeric heavy chain antibodies, known as VHH or Nanobody, has much potential in pharmaceutical and industrial applications. To establish the isolation process of antigen-specific VHH, a VHH phage library was constructed with a diversity of 8.4 × 10(7) from cDNA of peripheral blood mononuclear cells of an alpaca (Lama pacos) immunized with a fragment of IZUMO1 (IZUMO1PFF) as a model antigen. By conventional biopanning, 13 antigen-specific VHHs were isolated. The amino acid sequences of these VHHs, designated as N-group VHHs, were very similar to each other (>93% identity). To find more diverse antibodies, we performed high-throughput sequencing (HTS) of VHH genes. By comparing the frequencies of each sequence between before and after biopanning, we found the sequences whose frequencies were increased by biopanning. The top 100 sequences of them were supplied for phylogenic tree analysis. In total 75% of them belonged to N-group VHHs, but the other were phylogenically apart from N-group VHHs (Non N-group). Two of three VHHs selected from non N-group VHHs showed sufficient antigen binding ability. These results suggested that biopanning followed by HTS provided a useful method for finding minor and diverse antigen-specific clones that could not be identified by conventional biopanning. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

  12. Antibody guided irradiation of brain glioma by arterial infusion of radioactive monoclonal antibody against epidermal growth factor receptor and blood group A antigen

    Energy Technology Data Exchange (ETDEWEB)

    Epenetos, A.A.; Courtenay-Luck, N.; Pickering, D.; Hooker, G.; Lavender, J.P.; McKenzie, C.G. (Hammersmith Hospital, London (UK)); Durbin, H. (Imperial Cancer Research Fund, London (UK). Labs.)

    1985-05-18

    In a patient with recurrent grade IV glioma of the brain resistant to conventional treatment an antibody guided isotopic scan showed uptake by the tumour of a monoclonal antibody (9A) that was developed against epidermal growth factor receptor but cross reacted with blood group A antigen. As a therapeutic attempt antibody labelled with 1665 MBq (45.0 mCi) iodine-131 was delivered to the tumour area by infusion into the internal carotid artery. Computed tomography showed regression of the tumour after treatment, and an appreciable and sustained clinical improvement was noted without any toxicity. Delivery of irradiation guided by monoclonal antibody delivered by arterial infusion of the tumour area may be of clinical value in the treatment of brain gliomas resistant to conventional forms of treatment.

  13. 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.

  14. Humanised IgG1 antibody variants targeting membrane-bound carcinoembryonic antigen by antibody-dependent cellular cytotoxicity and phagocytosis.

    Science.gov (United States)

    Ashraf, S Q; Umana, P; Mössner, E; Ntouroupi, T; Brünker, P; Schmidt, C; Wilding, J L; Mortensen, N J; Bodmer, W F

    2009-11-17

    The effect of glycoengineering a membrane specific anti-carcinoembryonic antigen (CEA) (this paper uses the original term CEA for the formally designated CEACAM5) antibody (PR1A3) on its ability to enhance killing of colorectal cancer (CRC) cell lines by human immune effector cells was assessed. In vivo efficacy of the antibody was also tested. The antibody was modified using EBNA cells cotransfected with beta-1,4-N-acetylglucosaminyltransferase III and the humanised hPR1A3 antibody genes. The resulting alteration of the Fc segment glycosylation pattern enhances the antibody's binding affinity to the FcgammaRIIIa receptor on human immune effector cells but does not alter the antibody's binding capacity. Antibody-dependent cellular cytotoxicity (ADCC) is inhibited in the presence of anti-FcgammaRIII blocking antibodies. This glycovariant of hPR1A3 enhances ADCC 10-fold relative to the parent unmodified antibody using either unfractionated peripheral blood mononuclear or natural killer (NK) cells and CEA-positive CRC cells as targets. NK cells are far more potent in eliciting ADCC than either freshly isolated monocytes or granulocytes. Flow cytometry and automated fluorescent microscopy have been used to show that both versions of hPR1A3 can induce antibody-dependent cellular phagocytosis (ADCP) by monocyte-derived macrophages. However, the glycovariant antibody did not mediate enhanced ADCP. This may be explained by the relatively low expression of FcgammaRIIIa on cultured macrophages. In vivo studies show the efficacy of glycoengineered humanised IgG1 PR1A3 in significantly improving survival in a CRC metastatic murine model. The greatly enhanced in vitro ADCC activity of the glycoengineered version of hPR1A3 is likely to be clinically beneficial.

  15. Ultrasensitive direct competitive FLISA using highly luminescent quantum dot beads for tuning affinity of competing antigens to antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Sicheng; Zhou, Yaofeng; Huang, Xiaolin [State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047 (China); Yu, Ruijin [College of Science, Northwest A& F University, Yangling, Shaanxi 712100 (China); Lai, Weihua [State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047 (China); Xiong, Yonghua, E-mail: yhxiongchen@163.com [State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang 330047 (China)

    2017-06-15

    Herein, for the first time we report a novel direct competitive fluorescence-linked immunosorbent assay (dcFLISA) for the ultrasensitive detection of ochratoxin A (OTA) by introducing a large size polymer beads loaded with quantum dots (QBs) as carrier of competing antigen for decreasing binding affinity to antibody and enhancing the fluorescent signal intensity. When using 255 nm QBs as carrier of competing antigen, the equilibrium dissociation constant of QB based competing antigen to antibodies can be tuned to 100 times higher than that of the horseradish peroxidase (HRP) based competing antigen by controlling labeled amounts of antigen on the surface of QBs. Various parameters that influenced the sensitivity of dcFLISA were investigated and optimized. Under optimum detection parameters, the dynamic linear range of developed dcFLISA for detecting OTA was established at 0.05 pg/mL to 1.56 pg/mL with a half maximal inhibitory concentration at 0.14 ± 0.04 pg/mL (n = 5), which is three orders of magnitude lower than that of conventional HRP-based dcELISA (0.24 ng/mL). The developed FLISA is also highly accurate, reliable, and shows no cross reaction to other mycotoxins. In summary, the proposed method offers a straightforward approach to improve the sensitivity of direct competitive immunoassay for trace small chemical molecule detection in food quality control, environmental monitoring, and clinical diagnosis. - Highlights: • Highly luminescent QBs were used as a carrier of competing antigen for ultrasensitive detection of OTA. • It is the first time to use a large size QBs as a carrier for tuning affinity of competing antigen to antibodies. • IC{sub 50} value of QB-based dcFLISA is three orders of magnitude lower than that of HRP-based dcELISA.

  16. Ultrasensitive direct competitive FLISA using highly luminescent quantum dot beads for tuning affinity of competing antigens to antibodies

    International Nuclear Information System (INIS)

    Xiong, Sicheng; Zhou, Yaofeng; Huang, Xiaolin; Yu, Ruijin; Lai, Weihua; Xiong, Yonghua

    2017-01-01

    Herein, for the first time we report a novel direct competitive fluorescence-linked immunosorbent assay (dcFLISA) for the ultrasensitive detection of ochratoxin A (OTA) by introducing a large size polymer beads loaded with quantum dots (QBs) as carrier of competing antigen for decreasing binding affinity to antibody and enhancing the fluorescent signal intensity. When using 255 nm QBs as carrier of competing antigen, the equilibrium dissociation constant of QB based competing antigen to antibodies can be tuned to 100 times higher than that of the horseradish peroxidase (HRP) based competing antigen by controlling labeled amounts of antigen on the surface of QBs. Various parameters that influenced the sensitivity of dcFLISA were investigated and optimized. Under optimum detection parameters, the dynamic linear range of developed dcFLISA for detecting OTA was established at 0.05 pg/mL to 1.56 pg/mL with a half maximal inhibitory concentration at 0.14 ± 0.04 pg/mL (n = 5), which is three orders of magnitude lower than that of conventional HRP-based dcELISA (0.24 ng/mL). The developed FLISA is also highly accurate, reliable, and shows no cross reaction to other mycotoxins. In summary, the proposed method offers a straightforward approach to improve the sensitivity of direct competitive immunoassay for trace small chemical molecule detection in food quality control, environmental monitoring, and clinical diagnosis. - Highlights: • Highly luminescent QBs were used as a carrier of competing antigen for ultrasensitive detection of OTA. • It is the first time to use a large size QBs as a carrier for tuning affinity of competing antigen to antibodies. • IC_5_0 value of QB-based dcFLISA is three orders of magnitude lower than that of HRP-based dcELISA.

  17. Insecticide-treated bed nets reduce plasma antibody levels and limit the repertoire of antibodies to Plasmodium falciparum variant surface antigens

    DEFF Research Database (Denmark)

    Askjaer, N; Maxwell, C; Chambo, W

    2001-01-01

    The use of insecticide-treated bed nets (ITN) has been documented to reduce malaria morbidity and mortality in areas with endemic malaria, but concerns have been raised that ITN usage could affect the acquisition of malaria immunity. Several lines of evidence have indicated that antibodies against...... variant surface antigens (VSA) are important in the development of naturally acquired immunity to Plasmodium falciparum malaria and may thus be good indicators of immune status. We have compared the levels of VSA antibodies in plasma from children who have used ITN for 4 years to levels in plasma from...

  18. Effect of alterations in glomerular charge on deposition of cationic and anionic antibodies to fixed glomerular antigens in the rat.

    Science.gov (United States)

    Adler, S; Baker, P; Pritzl, P; Couser, W G

    1985-07-01

    Reduction of the negative charge of the glomerular capillary wall alters its charge- and size-selective properties. To investigate the effect of alteration in glomerular charge properties on antibody localization, we prepared cationic and anionic fractions of antibodies to subepithelial and glomerular basement membrane (GBM) antigens, and compared their deposition in normal rats and rats treated with protamine sulfate or aminonucleoside of puromycin to reduce capillary wall charge. IgG antibodies were eluted from kidneys of rats with active Heymann's nephritis (AICN), passive Heymann's nephritis (PHN), or anti-GBM nephritis (NTN), separated into cationic and anionic fractions, and radiolabeled with iodine 125 or iodine 131. Relative antibody content of each fraction was determined by incubation with an excess of glomerular antigen. Varying amounts of cationic and anionic IgG eluted from kidneys of rats with AICN or PHN were injected into 24 normal or protamine sulfate-treated rats. Glomerular binding of all antibodies was highly correlated with IgG delivery to the kidney. The ratio of cationic to anionic antibody deposited in the glomeruli of normal rats after 4 hours was 1.08 +/- 0.07 for AICN eluate and 0.37 +/- 0.04 for PHN eluate. The ratios were not significantly different in animals pretreated with protamine sulfate (1.15 +/- 0.06 and 0.44 +/- 0.06, respectively; P greater than 0.05). Varying amounts of cationic and anionic IgG eluted from kidneys of rats with NTN were injected into 10 normal rats and four rats treated with aminonucleoside of puromycin. Glomerular binding of antibody was again highly correlated with IgG delivery to the kidney. The ratio of cationic to anionic antibody deposited in the glomeruli of normal rats after 1 hour was 1.03 +/- 0.06, and was not significantly altered in rats treated with aminonucleoside of puromycin (1.05 +/- 0.03, P greater than 0.5). Proteinuria in PHN rats was also unaffected by treatment with protamine sulfate for

  19. Prediction of site-specific interactions in antibody-antigen complexes: the proABC method and server.

    KAUST Repository

    Olimpieri, Pier Paolo

    2013-06-26

    MOTIVATION: Antibodies or immunoglobulins are proteins of paramount importance in the immune system. They are extremely relevant as diagnostic, biotechnological and therapeutic tools. Their modular structure makes it easy to re-engineer them for specific purposes. Short of undergoing a trial and error process, these experiments, as well as others, need to rely on an understanding of the specific determinants of the antibody binding mode. RESULTS: In this article, we present a method to identify, on the basis of the antibody sequence alone, which residues of an antibody directly interact with its cognate antigen. The method, based on the random forest automatic learning techniques, reaches a recall and specificity as high as 80% and is implemented as a free and easy-to-use server, named prediction of Antibody Contacts. We believe that it can be of great help in re-design experiments as well as a guide for molecular docking experiments. The results that we obtained also allowed us to dissect which features of the antibody sequence contribute most to the involvement of specific residues in binding to the antigen. AVAILABILITY: http://www.biocomputing.it/proABC. CONTACT: anna.tramontano@uniroma1.it or paolo.marcatili@gmail.com SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

  20. 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.

  1. An integrated top-down and bottom-up proteomic approach to characterize the antigen-binding fragment of antibodies.

    Science.gov (United States)

    Dekker, Lennard; Wu, Si; Vanduijn, Martijn; Tolić, Nikolai; Stingl, Christoph; Zhao, Rui; Luider, Theo; Paša-Tolić, Ljiljana

    2014-05-01

    We have previously shown that different individuals exposed to the same antigen produce antibodies with identical mutations in their complementarity determining regions (CDR), suggesting that CDR tryptic peptides can serve as biomarkers for disease diagnosis and prognosis. Complete Fabs derived from disease specific antibodies have even higher potential; they could potentially be used for disease treatment and are required to identify the antigens toward which the antibodies are directed. However, complete Fab sequence characterization via LC-MS analysis of tryptic peptides (i.e. bottom-up) has proven to be impractical for mixtures of antibodies. To tackle this challenge, we have developed an integrated bottom-up and top-down MS approach, employing 2D chromatography coupled with Fourier transform mass spectrometry (FTMS), and applied this approach for full characterization of the variable parts of two pharmaceutical monoclonal antibodies with sensitivity comparable to the bottom-up standard. These efforts represent an essential step toward the identification of disease specific antibodies in patient samples with potentially significant clinical impact. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. High-throughput sequencing of natively paired antibody chains provides evidence for original antigenic sin shaping the antibody response to influenza vaccination.

    Science.gov (United States)

    Tan, Yann-Chong; Blum, Lisa K; Kongpachith, Sarah; Ju, Chia-Hsin; Cai, Xiaoyong; Lindstrom, Tamsin M; Sokolove, Jeremy; Robinson, William H

    2014-03-01

    We developed a DNA barcoding method to enable high-throughput sequencing of the cognate heavy- and light-chain pairs of the antibodies expressed by individual B cells. We used this approach to elucidate the plasmablast antibody response to influenza vaccination. We show that >75% of the rationally selected plasmablast antibodies bind and neutralize influenza, and that antibodies from clonal families, defined by sharing both heavy-chain VJ and light-chain VJ sequence usage, do so most effectively. Vaccine-induced heavy-chain VJ regions contained on average >20 nucleotide mutations as compared to their predicted germline gene sequences, and some vaccine-induced antibodies exhibited higher binding affinities for hemagglutinins derived from prior years' seasonal influenza as compared to their affinities for the immunization strains. Our results show that influenza vaccination induces the recall of memory B cells that express antibodies that previously underwent affinity maturation against prior years' seasonal influenza, suggesting that 'original antigenic sin' shapes the antibody response to influenza vaccination. Published by Elsevier Inc.

  3. The hypervariable region of Streptococcus pyogenes M protein escapes antibody attack by antigenic variation and weak immunogenicity

    DEFF Research Database (Denmark)

    Lannergård, Jonas; Gustafsson, Caj Ulrik Mattias; Waldemarsson, Johan

    2011-01-01

    Sequence variation of antigenic proteins allows pathogens to evade antibody attack. The variable protein commonly includes a hypervariable region (HVR), which represents a key target for antibodies and is therefore predicted to be immunodominant. To understand the mechanism(s) of antibody evasion...

  4. Determination of High-affinity Antibody-antigen Binding Kinetics Using Four Biosensor Platforms.

    Science.gov (United States)

    Yang, Danlin; Singh, Ajit; Wu, Helen; Kroe-Barrett, Rachel

    2017-04-17

    Label-free optical biosensors are powerful tools in drug discovery for the characterization of biomolecular interactions. In this study, we describe the use of four routinely used biosensor platforms in our laboratory to evaluate the binding affinity and kinetics of ten high-affinity monoclonal antibodies (mAbs) against human proprotein convertase subtilisin kexin type 9 (PCSK9). While both Biacore T100 and ProteOn XPR36 are derived from the well-established Surface Plasmon Resonance (SPR) technology, the former has four flow cells connected by serial flow configuration, whereas the latter presents 36 reaction spots in parallel through an improvised 6 x 6 crisscross microfluidic channel configuration. The IBIS MX96 also operates based on the SPR sensor technology, with an additional imaging feature that provides detection in spatial orientation. This detection technique coupled with the Continuous Flow Microspotter (CFM) expands the throughput significantly by enabling multiplex array printing and detection of 96 reaction sports simultaneously. In contrast, the Octet RED384 is based on the BioLayer Interferometry (BLI) optical principle, with fiber-optic probes acting as the biosensor to detect interference pattern changes upon binding interactions at the tip surface. Unlike the SPR-based platforms, the BLI system does not rely on continuous flow fluidics; instead, the sensor tips collect readings while they are immersed in analyte solutions of a 384-well microplate during orbital agitation. Each of these biosensor platforms has its own advantages and disadvantages. To provide a direct comparison of these instruments' ability to provide quality kinetic data, the described protocols illustrate experiments that use the same assay format and the same high-quality reagents to characterize antibody-antigen kinetics that fit the simple 1:1 molecular interaction model.

  5. Timing of the human prenatal antibody response to Plasmodium falciparum antigens.

    Directory of Open Access Journals (Sweden)

    Samuel Tassi Yunga

    Full Text Available Plasmodium falciparum (Pf-specific T- and B-cell responses may be present at birth; however, when during fetal development antibodies are produced is unknown. Accordingly, cord blood samples from 232 preterm (20-37 weeks of gestation and 450 term (≥37 weeks babies were screened for IgM to Pf blood-stage antigens MSP1, MSP2, AMA1, EBA175 and RESA. Overall, 25% [95% CI = 22-28%] of the 682 newborns were positive for IgM to ≥1 Pf antigens with the earliest response occurring at 22 weeks. Interestingly, the odds of being positive for cord blood Pf IgM decreased with gestational age (adjusted OR [95% CI] at 20-31 weeks = 2.55 [1.14-5.85] and at 32-36 weeks = 1.97 [0.92-4.29], with ≥37 weeks as reference; however, preterm and term newborns had similar levels of Pf IgM and recognized a comparable breadth of antigens. Having cord blood Pf IgM was associated with placental malaria (adjusted OR [95% CI] = 2.37 [1.25-4.54]. To determine if in utero exposure occurred via transplacental transfer of Pf-IgG immune complexes (IC, IC containing MSP1 and MSP2 were measured in plasma of 242 mother-newborn pairs. Among newborns of IC-positive mothers (77/242, the proportion of cord samples with Pf IC increased with gestational age but was not associated with Pf IgM, suggesting that fetal B cells early in gestation had not been primed by IC. Finally, when cord mononuclear cells from 64 term newborns were cultured in vitro, only 11% (7/64 of supernatants had Pf IgM; whereas, 95% (61/64 contained secreted Pf IgG. These data suggest fetal B cells are capable of making Pf-specific IgM from early in the second trimester and undergo isotype switching to IgG towards term.

  6. Acquired Antibody Responses against Plasmodium vivax Infection Vary with Host Genotype for Duffy Antigen Receptor for Chemokines (DARC)

    Science.gov (United States)

    Maestre, Amanda; Muskus, Carlos; Duque, Victoria; Agudelo, Olga; Liu, Pu; Takagi, Akihide; Ntumngia, Francis B.; Adams, John H.; Sim, Kim Lee; Hoffman, Stephen L.; Corradin, Giampietro; Velez, Ivan D.; Wang, Ruobing

    2010-01-01

    Background Polymorphism of the Duffy Antigen Receptor for Chemokines (DARC) is associated with susceptibility to and the severity of Plasmodium vivax malaria in humans. P. vivax uses DARC to invade erythrocytes. Individuals lacking DARC are ‘resistant’ to P. vivax erythrocytic infection. However, susceptibility to P. vivax in DARC+ individuals is reported to vary between specific DARC genotypes. We hypothesized that the natural acquisition of antibodies to P. vivax blood stages may vary with the host genotype and the level of DARC expression. Furthermore, high parasitemia has been reported to effect the acquisition of immunity against pre-erythrocytic parasites. We investigated the correlation between host DARC genotypes and the frequency and magnitude of antibodies against P. vivax erythrocytic stage antigens. Methodology/Findings We assessed the frequencies and magnitudes of antibody responses against P. vivax and P. falciparum sporozoite and erythrocytic antigens in Colombian donors from malaria-endemic regions. The frequency and level of naturally-acquired antibodies against the P. vivax erythrocytic antigens merozoite surface protein 1 (PvMSP1) and Duffy binding protein (PvDBP) varied with the host DARC genotypes. Donors with one negative allele (FY*B/FY*Bnull and FY*A/FY*Bnull) were more likely to have anti-PvMSP1 and anti-PvDBP antibodies than those with two positive alleles (FY*B/FY*B and FY*A/FY*B). The lower IgG3 and IgG1 components of the total IgG response may account for the decreased responses to P. vivax erythrocytic antigens with FY*A/FY*B and FY*B/FY*B genotypes. No such association was detected with P. falciparum erythrocytic antigens, which does not use DARC for erythrocyte invasion. Conclusion/Significance Individuals with higher DARC expression, which is associated with higher susceptibility to P. vivax infection, exhibited low frequencies and magnitudes of P. vivax blood-stage specific antibody responses. This may indicate that one of the

  7. Acquired antibody responses against Plasmodium vivax infection vary with host genotype for duffy antigen receptor for chemokines (DARC.

    Directory of Open Access Journals (Sweden)

    Amanda Maestre

    2010-07-01

    Full Text Available Polymorphism of the Duffy Antigen Receptor for Chemokines (DARC is associated with susceptibility to and the severity of Plasmodium vivax malaria in humans. P. vivax uses DARC to invade erythrocytes. Individuals lacking DARC are 'resistant' to P. vivax erythrocytic infection. However, susceptibility to P. vivax in DARC+ individuals is reported to vary between specific DARC genotypes. We hypothesized that the natural acquisition of antibodies to P. vivax blood stages may vary with the host genotype and the level of DARC expression. Furthermore, high parasitemia has been reported to effect the acquisition of immunity against pre-erythrocytic parasites. We investigated the correlation between host DARC genotypes and the frequency and magnitude of antibodies against P. vivax erythrocytic stage antigens.We assessed the frequencies and magnitudes of antibody responses against P. vivax and P. falciparum sporozoite and erythrocytic antigens in Colombian donors from malaria-endemic regions. The frequency and level of naturally-acquired antibodies against the P. vivax erythrocytic antigens merozoite surface protein 1 (PvMSP1 and Duffy binding protein (PvDBP varied with the host DARC genotypes. Donors with one negative allele (FY*B/FY*Bnull and FY*A/FY*Bnull were more likely to have anti-PvMSP1 and anti-PvDBP antibodies than those with two positive alleles (FY*B/FY*B and FY*A/FY*B. The lower IgG3 and IgG1 components of the total IgG response may account for the decreased responses to P. vivax erythrocytic antigens with FY*A/FY*B and FY*B/FY*B genotypes. No such association was detected with P. falciparum erythrocytic antigens, which does not use DARC for erythrocyte invasion.Individuals with higher DARC expression, which is associated with higher susceptibility to P. vivax infection, exhibited low frequencies and magnitudes of P. vivax blood-stage specific antibody responses. This may indicate that one of the primary mechanisms by which P. vivax evades

  8. Development of a solid-phase radioimmunoassay for antibody to antigens of Babesia bovis infected bovine erythrocytes

    Energy Technology Data Exchange (ETDEWEB)

    Kahl, L.P.; Anders, R.F.; Mitchell, G.F. (Walter and Eliza Hall Inst. of Medical Research, Parkville (Australia)); Callow, L.L.; Rodwell, B.J. (Animal Research Inst. Wacol (Australia). Tick Fever Research Centre)

    1982-06-01

    A quantitative solid-phase radioimmunoassay (RIA) has been developed for the purpose of ranking sera from exposed animals according to their titre of anti-B. bovis antibody. The antigen was a sonicate of lysed infected blood cells, and antibody binding was detected with /sup 125/I-labelled anti-bovine IgG. The assay was tested using sera from experimentally infected splenectomized and intact cattle and from animals resident in an endemic area. A high specificity for B. bovis was demonstrated. There was good agreement in identifying exposed cattle when the test was compared with an indirect fluorescent antibody (IFA) test although no correlation was seen between titres obtained in the two tests. Analysis of the effects of challenge infection with B. bovis on IFA and RIA titres in previously exposed animals illustrated that the RIA was a more sensitive test for detecting changes in antibody titre.

  9. Prevalence of Diego blood group antigen and the antibody in three ethnic population groups in Klang valley of Malaysia

    OpenAIRE

    Cheong Tar Wei; Faisal Muti Al-Hassan; Norris Naim; Aishah Knight; Sanmukh R Joshi

    2013-01-01

    Background: Diego blood group antigen, Di(a), is very rare among Caucasians and Blacks, but relatively common among the South American Indians and Asians of Mongolian origin. The antibody to Di(a) is clinically significant to cause hemolytic disease in a new-born or hemolytic transfusion reaction. Objectives: This study was designed to determine the prevalence of Di(a) antigen among the blood donors from the three major ethnic groups in Klang Valley of Malaysia as well as to find an incidence...

  10. Antibodies against high frequency Gerbich 2 antigen (anti-Ge2: A real challenge in cross matching lab

    Directory of Open Access Journals (Sweden)

    Ravindra P Singh

    2013-01-01

    Full Text Available Transfusion management of patients′ alloimmunized against high-prevalence erythrocyte antigens is often problematic in emergency situations. Gerbich (Ge is very common blood group system and Gerbich-2 (Ge-2 antigen present in high frequency and outside Papua New Guinea population, Ge-2 negative population almost nil. To manage such kind of problems with real emergencies, implementation of rare donor registry program, cryopreservation of red cells of rare donors and biological cross matching to assess significance of these antibodies is warranted.

  11. 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)

  12. Verifying Elimination Programs with a Special Emphasis on Cysticercosis Endpoints and Postelimination Surveillance

    Directory of Open Access Journals (Sweden)

    Sukwan Handali

    2012-01-01

    Full Text Available Methods are needed for determining program endpoints or postprogram surveillance for any elimination program. Cysticercosis has the necessary effective strategies and diagnostic tools for establishing an elimination program; however, tools to verify program endpoints have not been determined. Using a statistical approach, the present study proposed that taeniasis and porcine cysticercosis antibody assays could be used to determine with a high statistical confidence whether an area is free of disease. Confidence would be improved by using secondary tests such as the taeniasis coproantigen assay and necropsy of the sentinel pigs.

  13. Intravenous IgA complexed with antigen reduces primary antibody response to the antigen and anaphylaxis upon antigen re-exposure by inhibiting Th1 and Th2 activation in mice.

    Science.gov (United States)

    Yamaki, Kouya; Miyatake, Kenji; Nakashima, Takayuki; Morioka, Ayumi; Yamamoto, Midori; Ishibashi, Yuki; Ito, Ayaka; Kuranishi, Ayu; Yoshino, Shin

    2014-10-01

    Serum IgG, IgE and IgM have been shown to enhance the primary antibody responses upon exposure to the soluble antigens recognized by those antibodies. However, how IgA affects these responses remains unknown. We investigated the effects of intravenously administered monoclonal IgA on the immune responses in mice. DBA/1J mice were immunized with ovalbumin in the presence or absence of anti-ovalbumin monoclonal IgA. The Th1 and Th2 immune responses to ovalbumin and the anaphylaxis induced by re-exposure to ovalbumin were measured. IgA complexed with antigen attenuated the primary antibody responses to the antigen in mice, in contrast to IgG2b and IgE. The primary antibody responses, i.e. the de novo synthesis of anti-ovalbumin IgG2a, IgG1 and IgE in the serum, and the subsequent anaphylaxis induced with re-exposure to ovalbumin were reduced by the co-injection of anti-ovalbumin monoclonal IgA at ovalbumin immunization. The Th1, Th2 and Tr1 cytokines interferon-γ, interleukin-4 and interleukin-10, respectively, released from ovalbumin-restimulated cultured splenocytes collected from allergic mice were also reduced by the treatment. The induction of interferon-γ and interleukin-4 secretion by splenocytes from ovalbumin-immunized mice stimulated in vitro with ovalbumin was also significantly reduced by the antigen complexed with anti-ovalbumin IgA. These data suggest that the direct inhibition of Th1 and Th2 activation by anti-ovalbumin monoclonal IgA participates in the inhibition of the primary antibody responses. IgA plays important immunosuppressive roles under physiological and pathological conditions and is a promising candidate drug for the treatment of immune disorders.

  14. Characterisation of peptide microarrays for studying antibody-antigen binding using surface plasmon resonance imagery.

    Directory of Open Access Journals (Sweden)

    Claude Nogues

    Full Text Available BACKGROUND: Non-specific binding to biosensor surfaces is a major obstacle to quantitative analysis of selective retention of analytes at immobilized target molecules. Although a range of chemical antifouling monolayers has been developed to address this problem, many macromolecular interactions still remain refractory to analysis due to the prevalent high degree of non-specific binding. We describe how we use the dynamic process of the formation of self assembling monolayers and optimise physical and chemical properties thus reducing considerably non-specific binding and allowing analysis of specific binding of analytes to immobilized target molecules. METHODOLOGY/PRINCIPAL FINDINGS: We illustrate this approach by the production of specific protein arrays for the analysis of interactions between the 65kDa isoform of human glutamate decarboxylase (GAD65 and a human monoclonal antibody. Our data illustrate that we have effectively eliminated non-specific interactions with the surface containing the immobilised GAD65 molecules. The findings have several implications. First, this approach obviates the dubious process of background subtraction and gives access to more accurate kinetic and equilibrium values that are no longer contaminated by multiphase non-specific binding. Second, an enhanced signal to noise ratio increases not only the sensitivity but also confidence in the use of SPR to generate kinetic constants that may then be inserted into van't Hoff type analyses to provide comparative DeltaG, DeltaS and DeltaH values, making this an efficient, rapid and competitive alternative to ITC measurements used in drug and macromolecular-interaction mechanistic studies. Third, the accuracy of the measurements allows the application of more intricate interaction models than simple Langmuir monophasic binding. CONCLUSIONS: The detection and measurement of antibody binding by the type 1 diabetes autoantigen GAD65 represents an example of an antibody-antigen

  15. Radioimmunological study of the Australia antigen and its antibody in a rheumatic population

    Energy Technology Data Exchange (ETDEWEB)

    Imbert, M F

    1977-03-01

    AgAu as revealed by Blumberg is a surface antigen, whence its present name AgHBs. Anti-HBs antibodies are difficult to determine by conventional immunological methods whereas the radioimmunological technique is very sensitive. This emerges from numerous studies and also from the present work. The so-called 'sandwich' radioimmunological method appears highly sensitive, which certainly explains the large number of Ac anti-HBs carriers. We find the same observation on the part of many authors. It seems important to stress the following point. 14 of our subjects, in whom we found Ac anti-HBs, had undergone one or more tests for AgHBs and its Ac during previous hospitalisations, by electro-syneresis and passive hemaglutination. Some may perhaps have become 'positivised', but it may also be that the radioimmunological technique is more sensitive. No jaundice or other signs of viral hepatitis, no biological liver disturbances were observed meanwhile. For rheumatoid polyarthritis Ziegenfuss has even raised the following hypothesis: the rheumatoid factor, by interfering in the detection of Ag by immunoelectrophoresis, could mask its presence. A first study had shown the greater sensitivity of electrosyneresis than of passive hemaglutination. It may now be said that radioimmunology is more sensitive still.

  16. Variability in surface antigen expression on neuroblastoma cells as revealed by monoclonal antibodies

    International Nuclear Information System (INIS)

    Malpas, J.S.; Kemshead, J.T.; Pritchard, J.; Greaves, M.F.

    1982-01-01

    In treatment programmes for neuroblastoma involving autologous bone marrow transplantation, a problem exists in the identification of small numbers of metastatic tumour cells present in the marrow aspirates. Reinfusion of tumour cells along with normal bone marrow may reseed the tumour within a patient who has received high dose chemotherapy. Formalin-induced fluorescence in neuroblastoma is a possible diagnostic aid, but this method has no therapeutic potential. Other methods of detecting tumour relying on gross physiological changes in the patient are not suitable for diagnosis of minimal metastatic disease. As an immunological approach to the problem, rabbit antisera to neuroblastoma have been raised but these reagents suffer from low titre after absorption to make them specific. The authors have used the technique of somatic cell hybridisation to raise monoclonal antibodies which bind to neuroblastoma cells and not to normal haemopoietic progenitors. A panel of such reagents to demonstrate heterogeneity in antigen expression amongst metastatic neuroblastoma cells was employed in a radioimmunoassay as diagnostic aid for this problem. (Auth.)

  17. Radioimmunological study of the Australia antigen and its antibody in a rheumatic population

    International Nuclear Information System (INIS)

    Imbert, M.-F.

    1977-03-01

    AgAu as revealed by Blumberg is a surface antigen, whence its present name AgHBs. Anti-HBs antibodies are difficult to determine by conventional immunological methods whereas the radioimmunological technique is very sensitive. This emerges from numerous studies and also from the present work. The so-called 'sandwich' radioimmunological method appears highly sensitive, which certainly explains the large number of Ac anti-HBs carriers. We find the same observation on the part of many authors. It seems important to stress the following point. 14 of our subjects, in whom we found Ac anti-HBs, had undergone one or more tests for AgHBs and its Ac during previous hospitalisations, by electro-syneresis and passive hemaglutination. Some may perhaps have become 'positivised', but it may, also be that the radioimmunological technique is more sensitive. No jaundice or other signs of viral hepatitis, no biological liver disturbances were observed meanwhile. For rheumatoid polyarthritis Ziegenfuss has even raised the following hypothesis: the rheumatoid factor, by interfering in the detection of Ag by immunoelectrophoresis, could mask its presence. A first study had shown the greater sensitivity of electrosyneresis than of passive hemaglutination. It may now be said that radoimmunology is more sensitive still [fr

  18. Structural and Antigenic Definition of Hepatitis C Virus E2 Glycoprotein Epitopes Targeted by Monoclonal Antibodies

    Directory of Open Access Journals (Sweden)

    Giuseppe Sautto

    2013-01-01

    Full Text Available Hepatitis C virus (HCV is the major cause of chronic liver disease as well as the major indication for liver transplantation worldwide. Current standard of care is not completely effective, not administrable in grafted patients, and burdened by several side effects. This incomplete effectiveness is mainly due to the high propensity of the virus to continually mutate under the selective pressure exerted by the host immune response as well as currently administered antiviral drugs. The E2 envelope surface glycoprotein of HCV (HCV/E2 is the main target of the host humoral immune response and for this reason one of the major variable viral proteins. However, broadly cross-neutralizing monoclonal antibodies (mAbs directed against HCV/E2 represent a promising tool for the study of virus-host interplay as well as for the development of effective prophylactic and therapeutic approaches. In the last few years many anti-HCV/E2 mAbs have been evaluated in preclinical and clinical trials as possible candidate antivirals, particularly for administration in pre- and post-transplant settings. In this review we summarize the antigenic and structural characteristics of HCV/E2 determined through the use of anti-HCV/E2 mAbs, which, given the absence of a crystal structure of this glycoprotein, represent currently the best tool available.

  19. Antigen-antibody biorecognition events as discriminated by noise analysis of force spectroscopy curves.

    Science.gov (United States)

    Bizzarri, Anna Rita; Cannistraro, Salvatore

    2014-08-22

    Atomic force spectroscopy is able to extract kinetic and thermodynamic parameters of biomolecular complexes provided that the registered unbinding force curves could be reliably attributed to the rupture of the specific complex interactions. To this aim, a commonly used strategy is based on the analysis of the stretching features of polymeric linkers which are suitably introduced in the biomolecule-substrate immobilization procedure. Alternatively, we present a method to select force curves corresponding to specific biorecognition events, which relies on a careful analysis of the force fluctuations of the biomolecule-functionalized cantilever tip during its approach to the partner molecules immobilized on a substrate. In the low frequency region, a characteristic 1/f (α) noise with α equal to one (flickering noise) is found to replace white noise in the cantilever fluctuation power spectrum when, and only when, a specific biorecognition process between the partners occurs. The method, which has been validated on a well-characterized antigen-antibody complex, represents a fast, yet reliable alternative to the use of linkers which may involve additional surface chemistry and reproducibility concerns.

  20. Genotoxic effect and antigen binding characteristics of SLE auto-antibodies to peroxynitrite-modified human DNA.

    Science.gov (United States)

    Khan, Md Asad; Alam, Khursheed; Mehdi, Syed Hassan; Rizvi, M Moshahid A

    2017-12-01

    Systemic lupus erythematosus (SLE) is an inflammatory autoimmune disease characterized by auto-antibodies against native deoxyribonucleic acid after modification and is one of the reasons for the development of SLE. Here, we have evaluated the structural perturbations in human placental DNA by peroxynitrite using spectroscopy, thermal denaturation and high-performance liquid chromatography (HPLC). Peroxynitrite is a powerful potent bi-functional oxidative/nitrative agent that is produced both endogenously and exogenously. In experimental animals, the peroxynitrite-modified DNA was found to be highly immunogenic. The induced antibodies showed cross-reactions with different types of DNA and nitrogen bases that were modified with peroxynitrite by inhibition ELISA. The antibody activity was inhibited by approximately 89% with its immunogen as the inhibitor. The antigen-antibodies interaction between induced antibodies with peroxynitrite-modified DNA showed retarded mobility as compared to the native form. Furthermore, significantly increased binding was also observed in SLE autoantibodies with peroxynitrite-modified DNA than native form. Moreover, DNA isolated from lymphocyte of SLE patients revealed significant recognition of anti-peroxynitrite-modified DNA immunoglobulin G (IgG). Our data indicates that DNA modified with peroxynitrite presents unique antigenic determinants that may induce autoantibody response in SLE. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Two cases of intracerebral cysticercosis

    International Nuclear Information System (INIS)

    Nakase, Hiroyuki; Kamada, Kitaro; Inui, Shoji; Hiramatsu, Ken-ichiro; Okuchi, Kazuo; Minami, Shigenori; Araki, Kouji.

    1986-01-01

    We report 2 cases of intracerebral cysticercosis. One was followed up by CT with preservative treatment, and the other, treated surgically. Case 1: A 60-year-old man who had lived in Korea until the age of 12 and who had often eaten raw pork. He had been diagnosed as having cysticercosis after the excision of facial and somatic nodules. On January 17, 1980, he visited our clinic first with a complaint of generalized convulsions. CT revealed multiple low-density areas. For the subsequent 4 years, the patient was followed-up by CT. Meanwhile, the cyst became large and was calcified; in addition, brain atrophy progressed, and a new lesion of the cyst appeared. Case 2: A 50-year-old man who had also lived in Korea and who had also eaten raw pork often. He had been diagnosed as having ''cestodiasis'' in a gastro-intestinal hospital 7 or 8 years before. He visited our clinic because of sensory aphasia which developed on January 15, 1980. CT disclosed multiple low-density areas and a calcification of the left cerebellar hemisphere. Ring enhancement was also found on enhanced CT. The patient was then surgically treated. The excised specimen contained a three-layer structure characteristic of cysticercosis. The immunoelectrophoresis of the cyst fluid gave a positive result for the disease. Postoperatively, the symptoms improved. Intracerebral cysticercosis is a very rare disease in Japan. Its incidence, however, is likely to increase on account of the development of transportation. For this reason, and because of the necessity to differentiate it from a brain tumor or abscess on CT, it seems that this disease is of concern. (author)

  2. The chicken erythrocyte-specific MHC antigen. Characterization and purification of the B-G antigen by monoclonal antibodies

    DEFF Research Database (Denmark)

    Salomonsen, J; Skjødt, K; Crone, M

    1987-01-01

    and affinity-purified once more. Finally, reverse-phase chromatography resulted in a pure product. The B-G antigen was identified in the various fractions by rocket immunoelectrophoresis. The final product was more than 99% pure, as estimated by SDS-PAGE analysis followed by silver stain of proteins. The yield...

  3. Human Tregs Made Antigen Specific by Gene Modification: The Power to Treat Autoimmunity and Antidrug Antibodies with Precision

    Directory of Open Access Journals (Sweden)

    Patrick R. Adair

    2017-09-01

    Full Text Available Human regulatory CD4+ T cells (Tregs are potent immunosuppressive lymphocytes responsible for immune tolerance and homeostasis. Since the seminal reports identifying Tregs, vast research has been channeled into understanding their genesis, signature molecular markers, mechanisms of suppression, and role in disease. This research has opened the doors for Tregs as a potential therapeutic for diseases and disorders such as multiple sclerosis, type I diabetes, transplantation, and immune responses to protein therapeutics, like factor VIII. Seminal clinical trials have used polyclonal Tregs, but the frequency of antigen-specific Tregs among polyclonal populations is low, and polyclonal Tregs may risk non-specific immunosuppression. Antigen-specific Treg therapy, which uses genetically modified Tregs expressing receptors specific for target antigens, greatly mitigates this risk. Building on the principles of T-cell receptor cloning, chimeric antigen receptors (CARs, and a novel CAR derivative, called B-cell antibody receptors, our lab has developed different types of antigen-specific Tregs. This review discusses the current research and optimization of gene-modified antigen-specific human Tregs in our lab in several disease models. The preparations and considerations for clinical use of such Tregs also are discussed.

  4. Phage display used for gene cloning of human recombinant antibody against the erythrocyte surface antigen, rhesus D

    DEFF Research Database (Denmark)

    Dziegiel, M; Nielsen, L K; Andersen, P S

    1995-01-01

    A novel phage display system has been developed for PCR amplification and cloning of the Fab fragments of human immunoglobulin genes. Using this system, we have cloned an antibody from a mouse-human hybridoma cell line directed against the erythrocyte antigen rhesus D. Intact erythrocytes were used...... for absorption of the Fab phages. Soluble Fab fragments produced from the cloned material showed identical performance to the parental antibody in agglutination assays. Gel filtration confirmed that the Fab fragment consists of a kappa-Fd heterodimer. The successful use of intact cells for selection of specific...... Fab phages demonstrates that it is possible to by-pass purification of the antigen of interest. Comparison with published germline sequences demonstrated that the immunoglobulin coding regions had the highest homology to the VH 1.9III and V kappa Hum kappa v325 germline genes, respectively....

  5. Bovine cysticercosis in the European Union

    DEFF Research Database (Denmark)

    Blagojevic, Bojan; Robertson, Lucy J.; Vieira-Pinto, Madalena

    2017-01-01

    -only inspection of slaughtered cattle in order to reduce the potential for cross-contamination with bacteria that are of greatest public health risk, is expected in the European Union in the near future. With this system, the detection sensitivity for bovine cysticercosis that is already low with the current meat...... of bovine cysticercosis in the European Union....

  6. Experimental infection in cattle: kinetics of production of IgM and IgG against bovine cysticercosis and inflammatory response

    Directory of Open Access Journals (Sweden)

    Rafaella Paola Meneguete dos Guimarães-Peixoto

    2015-04-01

    Full Text Available Bovine cysticercosis is a zoonosis that affects humans in their adult form (taeniasis and its larval is found inserted in the musculature of infected cattle (cysticerci. It is still not entirely clear how animal immune response against infection occurs, being the comprehension of this process necessary for the enhancement of diagnostic capacity and disease prevention. This work aimed to evaluate the evolution of the immune response in experimentally infected cattle, compared with findings in cell response by optical microscopy. Nine animals were infected at a rate of 120,000 eggs of Taenia saginata. Five of the animals were similar in the kinetics of antibody production against cysticerci, with maximal levels of IgG and IgM. The other four animals showed an immune response different from the majority, with two of them showing delayed response to infection by cysticerci while the others apparently did not have initial contact with antigens secreted by cysticerci. Regarding the cellular response, it was found that, in lesions of viable cysticerci, inflammatory cells predominated, whereas in nonviable cysticerci there were tissue repair cells in the most part, being possible to notice that the amount of migratory calcareous corpuscles are related to the death stage of the parasite. These findings are important for the understanding immune response of cattle infected with cysticercosis.

  7. Antibodies to hepatitis A antigen in relation to the number of lifetime sexual partners in patients attending an STD clinic.

    OpenAIRE

    McFarlane, E S; Embil, J A; Manuel, F R; Thiébaux, H J

    1981-01-01

    Samples of serum from 421 patients attending a clinic for sexually transmitted diseases (STDs) were tested by radioimmunoassay for determination of the prevalence of antibodies to hepatitis A antigen (anti-HA). It was found that 42 . 4% of 33 homosexual men, 39 . 4% of 218 heterosexual men, and 38 . 8% of 170 female patients had positive results for anti-HA. The association between serological results and data on STD patients, using the variables of age, sexual type and preference, number of ...

  8. Association analysis of anti-Epstein-Barr nuclear antigen-1 antibodies, anti-cyclic citrullinated peptide antibodies, the shared epitope and smoking status in Brazilian patients with rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Michel Alexandre Yazbek

    2011-01-01

    Full Text Available INTRODUCTION: Epstein-Barr virus exposure appears to be an environmental trigger for rheumatoid arthritis that interacts with other risk factors. Relationships among anti-cyclic citrullinated peptide antibodies, the shared epitope, and smoking status have been observed in patients with rheumatoid arthritis from different populations. OBJECTIVE: To perform an association analysis of anti-Epstein-Barr nuclear antigen-1 antibodies, anti-cyclic citrullinated peptide antibodies, the shared epitope, and smoking status in Brazilian patients with rheumatoid arthritis. METHODS: In a case-control study, 140 rheumatoid arthritis patients and 143 healthy volunteers who were matched for age, sex, and ethnicity were recruited. Anti-Epstein-Barr nuclear antigen-1 antibodies and anti-cyclic citrullinated peptide antibodies were examined using an enzyme-linked immunosorbent assay, and shared epitope alleles were identified by genotyping. Smoking information was collected from all subjects. A comparative analysis of anti-Epstein-Barr nuclear antigen-1 antibodies, anti-cyclic citrullinated peptide antibodies, the shared epitope, and smoking status was performed in the patient group. Logistic regression analysis models were used to analyze the risk of rheumatoid arthritis. RESULTS: Anti-Epstein-Barr nuclear antigen-1 antibodies were not associated with anti-cyclic citrullinated peptide antibodies, shared epitope alleles, or smoking status. Anti-cyclic citrullinated peptide antibody positivity was significantly higher in smoking patients with shared epitope alleles (OR = 3.82. In a multivariate logistic regression analysis using stepwise selection, only anti-cyclic citrullinated peptide antibodies were found to be independently associated with rheumatoid arthritis (OR = 247.9. CONCLUSION: Anti-Epstein-Barr nuclear antigen-1 antibodies did not increase the risk of rheumatoid arthritis and were not associated with the rheumatoid arthritis risk factors studied. Smoking

  9. Differential recognition of the multiple banded antigen isoforms across Ureaplasma parvum and Ureaplasma urealyticum species by monoclonal antibodies.

    Science.gov (United States)

    Aboklaish, Ali F; Ahmed, Shatha; McAllister, Douglas; Cassell, Gail; Zheng, Xiaotian T; Spiller, Owen B

    2016-08-01

    Two separate species of Ureaplasma have been identified that infect humans: Ureaplasma parvum and Ureaplasma urealyticum. Most notably, these bacteria lack a cell wall and are the leading infectious organism associated with infection-related induction of preterm birth. Fourteen separate representative prototype bacterial strains, called serovars, are largely differentiated by the sequence of repeating units in the C-terminus of the major surface protein: multiple-banded antigen (MBA). Monoclonal antibodies that recognise single or small groups of serovars have been previously reported, but these reagents remain sequestered in individual research laboratories. Here we characterise a panel of commercially available monoclonal antibodies raised against the MBA and describe the first monoclonal antibody that cross-reacts by immunoblot with all serovars of U. parvum and U. urealyticum species. We also describe a recombinant MBA expressed by Escherichia coli which facilitated further characterisation by immunoblot and demonstrate immunohistochemistry of paraffin-embedded antigens. Immunoblot reactivity was validated against well characterised previously published monoclonal antibodies and individual commercial antibodies were found to recognise all U. parvum strains, only serovars 3 and 14 or only serovars 1 and 6, or all strains belonging to U. parvum and U. urealyticum. MBA mass was highly variable between strains, consistent with variation in the number of C-terminal repeats between strains. Antibody characterisation will enable future investigations to correlate severity of pathogenicity to MBA isoform number or mass, in addition to development of antibody-based diagnostics that will detect infection by all Ureaplasma species or alternately be able to differentiate between U. parvum, U. urealyticum or mixed infections. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. 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...

  11. Light-chain residue 95 is critical for antigen binding and multispecificity of monoclonal antibody G2.

    Science.gov (United States)

    Usui, Daiki; Inaba, Satomi; Kamatari, Yuji O; Ishiguro, Naotaka; Oda, Masayuki

    2017-09-02

    The monoclonal antibody, G2, specifically binds to the immunogen peptide derived from the chicken prion protein, Pep18mer, and two chicken proteins derived peptides, Pep8 and Pep395; G2 binds with equal affinity to Pep18mer. The amino acid sequences of the three peptides are completely different, and so the recognition mechanism of G2 is unique and interesting. We generated a single-chain Fv (scFv) antibody of G2, and demonstrated its correct folding with an antigen binding function similar to intact G2 antibody. We also generated a Pro containing mutant of G2 scFv at residue 95 of the light chain, and analyzed its antigen binding using a surface plasmon biosensor. The mutant lost its binding ability to Pep18mer, but remained those to Pep8 and Pep395. The results clearly indicate residue 95 as being critical for multispecific antigen binding of G2 at the site generated from the junctional diversity introduced at the joints between the V and J gene segments. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Systems Analysis Reveals High Genetic and Antigen-Driven Predetermination of Antibody Repertoires throughout B Cell Development

    Directory of Open Access Journals (Sweden)

    Victor Greiff

    2017-05-01

    Full Text Available Antibody repertoire diversity and plasticity is crucial for broad protective immunity. Repertoires change in size and diversity across multiple B cell developmental stages and in response to antigen exposure. However, we still lack fundamental quantitative understanding of the extent to which repertoire diversity is predetermined. Therefore, we implemented a systems immunology framework for quantifying repertoire predetermination on three distinct levels: (1 B cell development (pre-B cell, naive B cell, plasma cell, (2 antigen exposure (three structurally different proteins, and (3 four antibody repertoire components (V-gene usage, clonal expansion, clonal diversity, repertoire size extracted from antibody repertoire sequencing data (400 million reads. Across all three levels, we detected a dynamic balance of high genetic (e.g., >90% for V-gene usage and clonal expansion in naive B cells and antigen-driven (e.g., 40% for clonal diversity in plasma cells predetermination and stochastic variation. Our study has implications for the prediction and manipulation of humoral immunity.

  13. A single point in protein trafficking by Plasmodium falciparum determines the expression of major antigens on the surface of infected erythrocytes targeted by human antibodies.

    Science.gov (United States)

    Chan, Jo-Anne; Howell, Katherine B; Langer, Christine; Maier, Alexander G; Hasang, Wina; Rogerson, Stephen J; Petter, Michaela; Chesson, Joanne; Stanisic, Danielle I; Duffy, Michael F; Cooke, Brian M; Siba, Peter M; Mueller, Ivo; Bull, Peter C; Marsh, Kevin; Fowkes, Freya J I; Beeson, James G

    2016-11-01

    Antibodies to blood-stage antigens of Plasmodium falciparum play a pivotal role in human immunity to malaria. During parasite development, multiple proteins are trafficked from the intracellular parasite to the surface of P. falciparum-infected erythrocytes (IEs). However, the relative importance of different proteins as targets of acquired antibodies, and key pathways involved in trafficking major antigens remain to be clearly defined. We quantified antibodies to surface antigens among children, adults, and pregnant women from different malaria-exposed regions. We quantified the importance of antigens as antibody targets using genetically engineered P. falciparum with modified surface antigen expression. Genetic deletion of the trafficking protein skeleton-binding protein-1 (SBP1), which is involved in trafficking the surface antigen PfEMP1, led to a dramatic reduction in antibody recognition of IEs and the ability of human antibodies to promote opsonic phagocytosis of IEs, a key mechanism of parasite clearance. The great majority of antibody epitopes on the IE surface were SBP1-dependent. This was demonstrated using parasite isolates with different genetic or phenotypic backgrounds, and among antibodies from children, adults, and pregnant women in different populations. Comparisons of antibody reactivity to parasite isolates with SBP1 deletion or inhibited PfEMP1 expression suggest that PfEMP1 is the dominant target of acquired human antibodies, and that other P. falciparum IE surface proteins are minor targets. These results establish SBP1 as part of a critical pathway for the trafficking of major surface antigens targeted by human immunity, and have key implications for vaccine development, and quantifying immunity in populations.

  14. Cross-reactive Legionella antigens and the antibody response during infection

    DEFF Research Database (Denmark)

    Bangsborg, Jette Marie; Shand, G; Pearlman, E

    1991-01-01

    In order to define cross-reactive Legionella antigens suitable for diagnostic purposes, we investigated sonicate antigens from two Legionella species, including two serogroups of L. pneumophila. The antigens were reacted with heterologous and homologous rabbit antisera in Western blot. Sera from ...

  15. Human Monoclonal Islet Cell Antibodies From a Patient with Insulin- Dependent Diabetes Mellitus Reveal Glutamate Decarboxylase as the Target Antigen

    Science.gov (United States)

    Richter, Wiltrud; Endl, Josef; Eiermann, Thomas H.; Brandt, Michael; Kientsch-Engel, Rosemarie; Thivolet, Charles; Jungfer, Herbert; Scherbaum, Werner A.

    1992-09-01

    The autoimmune phenomena associated with destruction of the β cell in pancreatic islets and development of type 1 (insulin-dependent) diabetes mellitus (IDDM) include circulating islet cell antibodies. We have immortalized peripheral blood lymphocytes from prediabetic individuals and patients with newly diagnosed IDDM by Epstein-Barr virus transformation. IgG-positive cells were selected by anti-human IgG-coupled magnetic beads and expanded in cell culture. Supernatants were screened for cytoplasmic islet cell antibodies using the conventional indirect immunofluorescence test on cryostat sections of human pancreas. Six islet cell-specific B-cell lines, originating from a patient with newly diagnosed IDDM, could be stabilized on a monoclonal level. All six monoclonal islet cell antibodies (MICA 1-6) were of the IgG class. None of the MICA reacted with human thyroid, adrenal gland, anterior pituitary, liver, lung, stomach, and intestine tissues but all six reacted with pancreatic islets of different mammalian species and, in addition, with neurons of rat cerebellar cortex. MICA 1-6 were shown to recognize four distinct antigenic epitopes in islets. Islet cell antibody-positive diabetic sera but not normal human sera blocked the binding of the monoclonal antibodies to their target epitopes. Immunoprecipitation of 35S-labeled human islet cell extracts revealed that a protein of identical size to the enzyme glutamate decarboxylase (EC 4.1.1.15) was a target of all MICA. Furthermore, antigen immunotrapped by the MICA from brain homogenates showed glutamate decarboxylase enzyme activity. MICA 1-6 therefore reveal glutamate decarboxylase as the predominant target antigen of cytoplasmic islet cell autoantibodies in a patient with newly diagnosed IDDM.

  16. Crystal structure of the anti-(carcinoembryonic antigen) single-chain Fv antibody MFE-23 and a model for antigen binding based on intermolecular contacts.

    Science.gov (United States)

    Boehm, M K; Corper, A L; Wan, T; Sohi, M K; Sutton, B J; Thornton, J D; Keep, P A; Chester, K A; Begent, R H; Perkins, S J

    2000-03-01

    MFE-23 is the first single-chain Fv antibody molecule to be used in patients and is used to target colorectal cancer through its high affinity for carcinoembryonic antigen (CEA), a cell-surface member of the immunoglobulin superfamily. MFE-23 contains an N-terminal variable heavy-chain domain joined by a (Gly(4)Ser)(3) linker to a variable light-chain (V(L)) domain (kappa chain) with an 11-residue C-terminal Myc-tag. Its crystal structure was determined at 2.4 A resolution by molecular replacement with an R(cryst) of 19.0%. Five of the six antigen-binding loops, L1, L2, L3, H1 and H2, conformed to known canonical structures. The sixth loop, H3, displayed a unique structure, with a beta-hairpin loop and a bifurcated apex characterized by a buried Thr residue. In the crystal lattice, two MFE-23 molecules were associated back-to-back in a manner not seen before. The antigen-binding site displayed a large acidic region located mainly within the H2 loop and a large hydrophobic region within the H3 loop. Even though this structure is unliganded within the crystal, there is an unusually large region of contact between the H1, H2 and H3 loops and the beta-sheet of the V(L) domain of an adjacent molecule (strands DEBA) as a result of intermolecular packing. These interactions exhibited remarkably high surface and electrostatic complementarity. Of seven MFE-23 residues predicted to make contact with antigen, five participated in these lattice contacts, and this model for antigen binding is consistent with previously reported site-specific mutagenesis of MFE-23 and its effect on CEA binding.

  17. Isolation of scFv antibody fragments against HER2 and CEA tumor antigens from combinatorial antibody libraries derived from cancer patients.

    Science.gov (United States)

    Ayat, Hoda; Burrone, Oscar R; Sadghizadeh, Majid; Jahanzad, Eissa; Rastgou, Nasrin; Moghadasi, Sarrira; Arbabi, Mehdi

    2013-11-01

    Tumor cells expressing HER-2/neu and CEA antigens are potentially ideal targets for antibody-targeted therapy. In this study, two large human combinatorial libraries have been generated from the lymph nodes of breast cancer patients that express HER2 and CEA antigens in their tumors. These 'immune' libraries have been constructed in two different formats of scFv, differing in the length of the peptide linker connecting the two variable VH and VL domains. Libraries derived from these patients may contain a larger pool of anti-tumor antigen antibodies and are useful repertoire for isolating scFvs against any tumor markers. The results of this study showed that we were successful in obtaining human scFvs against HER-2/neu and CEA. For HER-2, cell-panning strategy was performed and resulted in two scFv binders that detected the complete HER-2 receptor on the cell membrane and internalized to the cells. Also, preliminary ELISA data showed that several anti-CEA scFv binders were isolated by panning. Copyright © 2013 The International Alliance for Biological Standardization. All rights reserved.

  18. Enhancement by gamma-interferon of in vivo tumor radiolocalization by a monoclonal antibody against HLA-DR antigen

    International Nuclear Information System (INIS)

    Rowlinson, G.; Balkwill, F.; Snook, D.; Hooker, G.; Epenetos, A.A.

    1986-01-01

    Athymic nu/nu (nude) mice bearing s.c. human breast tumors were treated systemically with recombinant human gamma-interferon. These tumors were phenotypically negative for HLA-DR prior to therapy, but after 4 days of treatment, 80% of the cells expressed this antigen in vivo as assessed by immunoperoxidase (F. R. Balkwill et al., Eur. J. Cancer Clin. Oncol., in press, 1986). A radioiodine-labeled murine monoclonal antibody (TAL-1B5) against HLA-DR specifically localized to the tumors in recombinant human gamma-interferon-treated but not in control mice. An isotype-identical murine monoclonal antibody that did not react with control or recombinant human gamma-interferon-treated tumors did not show any specific localization. These results demonstrate that specific localization to tumors of radio-labeled monoclonal antibodies to HLA-DR can be facilitated by systemic therapy with gamma-interferon

  19. 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....

  20. Antigen-binding properties of monoclonal antibodies reactive with EBNA1 and use in immunoaffinity chromatography.

    Directory of Open Access Journals (Sweden)

    Sarah J Duellman

    Full Text Available Epstein-Barr virus (EBV nuclear antigen 1 (EBNA1 was overexpressed and purified from Escherichia coli. Mouse monoclonal antibodies (mAbs were prepared that react with EBNA1. Eleven high affinity mAbs were recovered. Nine mAbs are isotype IgG (all subisotype IgG(1 and two mAbs are isotype IgM. All mAbs react strongly with EBNA1 in an ELISA assay while only one mAb (designated 1EB6 fails to react in a Western blot assay. The epitopes for these mAbs were mapped to seven different regions, providing good coverage of the entire EBNA1 protein. The mAbs had differing affinity for an EBNA1/DNA complex with four mAbs able to supershift the complex completely. All mAbs can immunoprecipitate EBNA1 from E. coli overexpressing EBNA1. A modified ELISA assay, termed ELISA-elution assay, was used to screen for mAbs that release EBNA1 in the presence of a low molecular weight polyhydroxylated compound (polyol and a nonchaotropic salt. MAbs with this property, termed polyol-responsive (PR-mAbs, allow gentle elution of labile proteins and protein complexes. Four mAbs are polyol-responsive with two showing usefulness in gentle immunoaffinity chromatography. Purification with these PR-mAbs may be useful in purifying EBNA1 complexes and elucidating EBNA1-associated proteins. This panel of anti-EBNA1 mAbs will advance the study of EBV by providing new tools to detect and purify EBNA1.

  1. Antibody Binding Selectivity: Alternative Sets of Antigen Residues Entail High-Affinity Recognition.

    Directory of Open Access Journals (Sweden)

    Yves Nominé

    Full Text Available Understanding the relationship between protein sequence and molecular recognition selectivity remains a major challenge. The antibody fragment scFv1F4 recognizes with sub nM affinity a decapeptide (sequence 6TAMFQDPQER15 derived from the N-terminal end of human papilloma virus E6 oncoprotein. Using this decapeptide as antigen, we had previously shown that only the wild type amino-acid or conservative replacements were allowed at positions 9 to 12 and 15 of the peptide, indicating a strong binding selectivity. Nevertheless phenylalanine (F was equally well tolerated as the wild type glutamine (Q at position 13, while all other amino acids led to weaker scFv binding. The interfaces of complexes involving either Q or F are expected to diverge, due to the different physico-chemistry of these residues. This would imply that high-affinity binding can be achieved through distinct interfacial geometries. In order to investigate this point, we disrupted the scFv-peptide interface by modifying one or several peptide positions. We then analyzed the effect on binding of amino acid changes at the remaining positions, an altered susceptibility being indicative of an altered role in complex formation. The 23 starting variants analyzed contained replacements whose effects on scFv1F4 binding ranged from minor to drastic. A permutation analysis (effect of replacing each peptide position by all other amino acids except cysteine was carried out on the 23 variants using the PEPperCHIP® Platform technology. A comparison of their permutation patterns with that of the wild type peptide indicated that starting replacements at position 11, 12 or 13 modified the tolerance to amino-acid changes at the other two positions. The interdependence between the three positions was confirmed by SPR (Biacore® technology. Our data demonstrate that binding selectivity does not preclude the existence of alternative high-affinity recognition modes.

  2. Novel Monoclonal Antibodies Recognizing Human Prostate-Specific Membrane Antigen (PSMA) as Research and Theranostic Tools.

    Science.gov (United States)

    Nováková, Zora; Foss, Catherine A; Copeland, Benjamin T; Morath, Volker; Baranová, Petra; Havlínová, Barbora; Skerra, Arne; Pomper, Martin G; Barinka, Cyril

    2017-05-01

    Prostate-specific membrane antigen (PSMA) is a validated target for the imaging and therapy of prostate cancer. Here, we report the detailed characterization of four novel murine monoclonal antibodies (mAbs) recognizing human PSMA as well as PSMA orthologs from different species. Performance of purified mAbs was assayed using a comprehensive panel of in vitro experimental setups including Western blotting, immunofluorescence, immunohistochemistry, ELISA, flow cytometry, and surface-plasmon resonance. Furthermore, a mouse xenograft model of prostate cancer was used to compare the suitability of the mAbs for in vivo applications. All mAbs demonstrate high specificity for PSMA as documented by the lack of cross-reactivity to unrelated human proteins. The 3F11 and 1A11 mAbs bind linear epitopes spanning residues 226-243 and 271-288 of human PSMA, respectively. 3F11 is also suitable for the detection of PSMA orthologs from mouse, pig, dog, and rat in experimental setups where the denatured form of PSMA is used. 5D3 and 5B1 mAbs recognize distinct surface-exposed conformational epitopes and are useful for targeting PSMA in its native conformation. Most importantly, using a mouse xenograft model of prostate cancer we show that both the intact 5D3 and its Fab fragment are suitable for in vivo imaging. With apparent affinities of 0.14 and 1.2 nM as determined by ELISA and flow cytometry, respectively, 5D3 has approximately 10-fold higher affinity for PSMA than the clinically validated mAb J591 and, therefore, is a prime candidate for the development of next-generation theranostics to target PSMA. Prostate 77:749-764, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  3. Outcome of limbic encephalitis with VGKC-complex antibodies: relation to antigenic specificity.

    Science.gov (United States)

    Malter, M P; Frisch, C; Schoene-Bake, J C; Helmstaedter, C; Wandinger, K P; Stoecker, W; Urbach, H; Surges, R; Elger, C E; Vincent, A V; Bien, C G

    2014-09-01

    In limbic encephalitis (LE) with antibodies (Abs) to the voltage-gated potassium channel complex (VGKC), the Abs are mainly directed to the VGKC-complex proteins, leucine-rich, glioma inactivated 1 protein (LGI1) or contactin-associated protein-like 2 (CASPR-2) or neither. Here, we relate the outcomes of VGKC-LE patients to the presence of Abs to LGI1, CASPR-2 or neither antigen (LGI1/CASPR-2-Ab(-)). Clinical, neuropsychology and MRI data were obtained from patient records for all LE patients from the Bonn Epilepsy Centre positive for VGKC-Abs by radioimmunoprecipitation assay between 2002 and 2011. Eighteen VGKC-LE patients were identified: nine patients (50 %) had LGI1-Abs, three (16 %) had CASPR-2-Abs; and six (33 %) were negative for both LGI1- and CASPR-2-Abs. At first assessment, the groups did not differ clinically or radiologically, but faciobrachial dystonic seizures were only observed in two LGI1-Ab(+) patients. All patients received monthly intravenous methylprednisolone (MP) pulses. At the most recent follow up (median 26 months), thirteen (72 %) were seizure-free, and seizure-freedom rates did not differ between the Ab groups. Hippocampal atrophy had developed in 7/9 LGI1-Ab(+) patients, but in none of the CASPR-2-Ab(+) or LGI/CASPR-2-Ab(-) patients (p = 0.003). While all subgroups improved, memory scores only normalized in six patients (33 %) and LGI1-Ab(+) patients were left with significantly poorer memory than the other two subgroups. Most VGKC-LE patients become seizure-free with pulsed monthly MP, but memory outcome is less favourable. Hippocampal atrophy and poor memory recovery is common in patients with LGI1-Abs and suggests permanent functional damage. More intense immunotherapies could improve outcomes in LGI1-Ab(+)-LE.

  4. Effect of radiation on the expression of tumor-associated antigens of human lung adenocarcinoma cells. Immunological study using monoclonal antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Hareyama, Masato

    1988-12-01

    We studied the effects of irradiation on the expression of a tumor-associated antigen (YH206 antigen) of cultured human lung adenocarcinoma A549 cells by using enzyme-linked immunosorbent assay (ELISA) and flow cytometry. YH206 antigen is preferentially expressed on adenocarcinoma cells. Irradiation of A549 cells remarkably increased the expression of YH206 antigen on the cell surface and the level of the antigen in the culture supernatant as well as in the cell lysate, whereas it significantly affected the expression of HLA (MHC-class I) antigen on the same cells. The expression of HLA antigen on the cell was also increased after treatment of the cells with interferon-..gamma... In an additional experiment, cells were stained simultaneously for surface antigens (fluorescein coupled antibodies) and for DNA content (propidium iodide), and then dual parameter measurements were performed by flow cytometry to analyse the relationship between antigen levels and the cell cycle. YH206 antigen and HLA antigen increased more in the S and G/sub 2//M phases of the cell cycle than in G/sub 0//G/sub 1/. The expression of YH206 antigen was enhanced in the S and G/sub 2//M phases by irradiation, whereas the expression of HLA antigen was enhanced in each phase of the cell cycle with irradiation or IFN. These results suggest that irradiation plays a key role in the change of the expression of certain tumor-associated antigens.

  5. 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

  6. Radioimmunoassay for Epstein-Barr Virus (EBV)-associated Nuclear Antigen (EBNA). Binding of iodinated antibodies to antigen immobilized in polyacrylamide gel

    International Nuclear Information System (INIS)

    Dolken, G.; Klein, G.

    1977-01-01

    A solid-phase radioimmunoassay was developed for the EBV-associated nuclear antigen (EBNA). Total homogenates of EBV-DNA and EBNA positive or negative cells were polymerized in polyacrylamide gel and compared for their ability to bind 125 I-IgG prepared from anti-EBNA positive and anti-EBNA negative sera. EBNA specific binding was demonstrated and confirmed by serological and cellular specificity controls. The assay allows the quantitation of antigen or antibody even in the presence of detergents and is suitable for biochemical characterization of the antigen. Reciprocal blocking studies with extracts from different cell lines showed quantitative and qualitative differences. One part of the EBNA specificiti(es) present in the human Burkitt lymphoma derived lines RAJI, DAUDI and AW-RAMOS was lacking in B96-8, a marmoset line carrying EBV derived from a human infectious mononucleosis line. This result may reflect differences in the viral genomes derived from Burkitt lymphoma and infectious mononucleosis lines or differences in the host cells. (author)

  7. 19-DEJ-1, a hemidesmosome-anchoring filament complex-associated monoclonal antibody. Definition of a new skin basement membrane antigenic defect in junctional and dystrophic epidermolysis bullosa

    DEFF Research Database (Denmark)

    Fine, J D; Horiguchi, Y; Couchman, J R

    1989-01-01

    A murine monoclonal antibody (19-DEJ-1) was recently produced that recognizes a unique antigenic epitope of human skin basement membrane localized to the midlamina lucida exclusively in those areas bordered by overlying hemidesmosomes. To determine whether the antigen defined by 19-DEJ-1 is norma...

  8. A compact phage display human scFv library for selection of antibodies to a wide variety of antigens

    Directory of Open Access Journals (Sweden)

    Kristensen Peter

    2009-01-01

    Full Text Available Abstract Background Phage display technology is a powerful new tool for making antibodies outside the immune system, thus avoiding the use of experimental animals. In the early days, it was postulated that this technique would eventually replace hybridoma technology and animal immunisations. However, since this technology emerged more than 20 years ago, there have only been a handful reports on the construction and application of phage display antibody libraries world-wide. Results Here we report the simplest and highly efficient method for the construction of a highly useful human single chain variable fragment (scFv library. The least number of oligonucleotide primers, electroporations and ligation reactions were used to generate a library of 1.5 × 108 individual clones, without generation of sub-libraries. All possible combinations of heavy and light chains, among all immunoglobulin isotypes, were included by using a mixture of primers and overlapping extension PCR. The key difference from other similar libraries was the highest diversity of variable gene repertoires, which was derived from 140 non-immunized human donors. A wide variety of antigens were successfully used to affinity select specific binders. These included pure recombinant proteins, a hapten and complex antigens such as viral coat proteins, crude snake venom and cancer cell surface antigens. In particular, we were able to use standard bio-panning method to isolate antibody that can bind to soluble Aflatoxin B1, when using BSA-conjugated toxin as a target, as demonstrated by inhibition ELISA. Conclusion These results suggested that by using an optimized protocol and very high repertoire diversity, a compact and efficient phage antibody library can be generated. This advanced method could be adopted by any molecular biology laboratory to generate both naïve or immunized libraries for particular targets as well as for high-throughput applications.

  9. A monoclonal antibody against SV40 large T antigen (PAb416) does not label Merkel cell carcinoma.

    Science.gov (United States)

    Pelletier, Daniel J; Czeczok, Thomas W; Bellizzi, Andrew M

    2018-07-01

    Merkel cell carcinoma represents poorly differentiated neuroendocrine carcinoma of cutaneous origin. In most studies, the vast majority of Merkel cell carcinomas are Merkel cell polyomavirus (MCPyV)-associated. SV40 polyomavirus immunohistochemistry is typically used in the diagnosis of other polyomavirus-associated diseases, including tubulointerstitial nephritis and progressive multifocal leukoencephalopathy, given cross-reactivity with BK and JC polyomaviruses. MCPyV-specific immunohistochemistry is commercially available, but, if antibodies against SV40 also cross-reacted with MCPyV, that would be advantageous from a resource-utilisation perspective. Tissue microarrays were constructed from 39 Merkel cell carcinomas, 24 small-cell lung carcinomas, and 18 extrapulmonary visceral small-cell carcinomas. SV40 large T antigen immunohistochemistry (clone PAb416) was performed; MCPyV large T antigen immunohistochemistry (clone CM2B4) had been previously performed. UniProt was used to compare the amino acid sequences of the SV40, BK, JC and MCPyV large T antigens, focusing on areas recognised by the PAb416 and CM2B4 clones. SV40 immunohistochemistry was negative in all tumours; MCPyV immunohistochemistry was positive in 38% of Merkel cell carcinomas and in 0% of non-cutaneous poorly differentiated neuroendocrine carcinomas. UniProt analysis revealed a high degree of similarity between SV40, BK, and JC viruses in the region recognised by PAb416. There was less homology between SV40 and MCPyV in this region, which was also interrupted by two long stretches of amino acids unique to MCPyV. The CM2B4 clone recognises a unique epitope in one of these stretches. The PAb416 antibody against the SV40 large T antigen does not cross-react with MCPyV large T antigen, and thus does not label Merkel cell carcinoma. © 2018 John Wiley & Sons Ltd.

  10. Towards the international collaboration for detection, surveillance and control of taeniasis/ cysticercosis and echinococcosis in Asia and the Pacific.

    Science.gov (United States)

    Ito, Akira; Wandra, Toni; Sato, Marcello O; Mamuti, Wulamu; Xiao, Ning; Sako, Yasuhito; Nakao, Minoru; Yamasaki, Hiroshi; Nakaya, Kazuhiro; Okamoto, Munehiro; Craig, Philip S

    2006-01-01

    Both cysticercosis and echinococcosis are potentially among the most serious helminth zoonoses threatening human health worldwide. However, due to the lack of reliable tools for confirmation or identification of patients or infected animals, epidemiological data are expected to be underestimated. Conversely, sometimes, such data are over estimated due to the lack of specificity. The most important issue for doing field surveys is that they use evidence based science. In this communication, advanced immunological and molecular tools for detection of individuals infected with either metacestodes or adult tapeworms are briefly overviewed, and the applications of such tools for epidemiological surveys in Indonesia, China and other countries are introduced. As immunological tools are based on antigen-antibody responses, there may exist some cross-reactions. Therefore, immunodiagnostic tools are expected to be useful for primary screening, and should be combined with confirmation of direct parasitological evidence (morphology or DNA), and imaging techniques for cysts. As a risk factor for human cysticercosis is the presence of tapeworm carriers, detection of taeniasis cases and differentiation of the three human Taenia species (Taenia solium, T. saginata and T. asiatica) in Asia and the Pacific requires consideration. Similarly, in northwest China, Echinococcus granulosus and E. multilocularis are coendemic and differentiation of these species is required in humans and definitive hosts. It is stressed that combination of several tools for identification of the parasite and for confirmation of diseases is important for obtaining highly reliable data before consideration of control of these zoonoses. Recent projects coordinated by Asahikawa Medical College have concentrated on immunological and molecular diagnostic techniques transferable to colleagues from endemic regions of Asia and the Pacific, and on organization of two international symposia to establish a platform

  11. Factors associated with anti-human leukocyte antigen antibodies in patients supported with continuous-flow devices and effect on probability of transplant and post-transplant outcomes

    DEFF Research Database (Denmark)

    Alba, Ana C; Tinckam, Kathryn; Foroutan, Farid

    2015-01-01

    BACKGROUND: One major disadvantage of ventricular assist device (VAD) therapy is the development of human-leukocyte antigen (HLA) antibodies. We aimed to identify factors associated with HLA antibodies during continuous flow (CF)-VAD support and assess the effect on transplant probability...

  12. Immunization of rhesus macaques with Echinococcus multilocularis recombinant 14-3-3 antigen leads to specific antibody response.

    Science.gov (United States)

    Lampe, Karen; Gottstein, B; Becker, T; Stahl-Hennig, C; Kaup, F-J; Mätz-Rensing, K

    2017-01-01

    E. multilocularis (Em) is the etiologic agent of alveolar echinococcosis (AE), a severe and potentially fatal disease, primarily affecting the liver of and occurring in aberrant intermediate hosts, e.g., humans and non-human primates. Due to increasing numbers of spontaneous cases of AE in the Old World monkey colonies of the German Primate Center, the question arose as to whether vaccination of non-human primates may represent a useful prophylactic approach. In this pilot study, the recombinant antigen Em14-3-3, which has provided a 97 % protection against E. multilocularis challenge infection in rodent models, was used for the first time to immunize rhesus macaques. In order to increase immunogenicity, the antigen was formulated with different adjuvants including Quil A®, aluminum hydroxide (alum), and muramyl dipeptide (MDP). Also, different vaccination regimens were tested. All vaccinated animals developed antigen-specific antibodies. While Quil A® induced a local adverse reaction, alum proved to be the most potent adjuvant in terms of induced antibody levels, longevity as well as tolerability. In conclusion, our pilot study demonstrated that recombinant Em14-3-3 is safe and immunogenic in rhesus monkeys. As a next step, efficacy of the vaccination remains to be explored.

  13. Assay of anti-HBs antibodies using a recombinant antigen and latex particle counting: comparison with five commercial tests.

    Science.gov (United States)

    Galanti, L M; Cornu, C; Masson, P L; Robert, A R; Becheanu, D; Lamy, M E; Cambiaso, C L

    1991-05-01

    An assay of anti-HBs antibodies based on agglutination of latex particles coated with recombinant HBs-antigen was compared with Abbott radioimmunoassay (Abbott-RIA), which uses a human plasma-derived antigen. The population examined consisted of 76 Abbott-RIA anti-HBs-negative prevaccinated subjects and 1044 serum samples anti-HBs found positive by Abbott-RIA, including 283 samples of subjects vaccinated either with a human plasma-derived vaccine (group A; n = 180) or with a recombinant vaccine (group B; n = 103). Correlation coefficients between the two techniques were respectively r = 0.89 for the whole population (n = 1044), r = 0.98 in group A and r = 0.74 in group B. Anti-HBs titres were higher with latex than with RIA in group B as shown by the regression slopes: latex = 508 + 1.11 RIA in group A and latex = -1138 + 3.97 RIA in group B, suggesting that some vaccinated subjects from group B produced antibodies against epitopes proper to the recombinant antigen. In the prevaccinated population and in group A, the latex results were compared with those of radioimmunoassays (Abbott, Sorin) and enzyme immunoassays (Behring, Roche, Pasteur). Only the Roche-EIA detected anti-HBs in the prevaccinated subjects. The correlation between the various immunoassays was r greater than 0.96 only for values higher than 100 IU/l.

  14. A novel IgE antibody targeting the prostate-specific antigen as a potential prostate cancer therapy

    International Nuclear Information System (INIS)

    Daniels-Wells, Tracy R; Nicodemus, Christopher F; Penichet, Manuel L; Helguera, Gustavo; Leuchter, Richard K; Quintero, Rafaela; Kozman, Maggie; Rodríguez, José A; Ortiz-Sánchez, Elizabeth; Martínez-Maza, Otoniel; Schultes, Birgit C

    2013-01-01

    Prostate cancer (PCa) is the second leading cause of cancer deaths in men in the United States. The prostate-specific antigen (PSA), often found at high levels in the serum of PCa patients, has been used as a marker for PCa detection and as a target of immunotherapy. The murine IgG1 monoclonal antibody AR47.47, specific for human PSA, has been shown to enhance antigen presentation by human dendritic cells and induce both CD4 and CD8 T-cell activation when complexed with PSA. In this study, we explored the properties of a novel mouse/human chimeric anti-PSA IgE containing the variable regions of AR47.47 as a potential therapy for PCa. Our goal was to take advantage of the unique properties of IgE in order to trigger immune activation against PCa. Binding characteristics of the antibody were determined by ELISA and flow cytometry. In vitro degranulation was determined by the release of β-hexosaminidase from effector cells. In vivo degranulation was monitored in human FcεRIα transgenic mice using the passive cutaneous anaphylaxis assay. These mice were also used for a vaccination study to determine the in vivo anti-cancer effects of this antibody. Significant differences in survival were determined using the Log Rank test. In vitro T-cell activation was studied using human dendritic cells and autologous T cells. The anti-PSA IgE, expressed in murine myeloma cells, is properly assembled and secreted, and binds the antigen and FcεRI. In addition, this antibody is capable of triggering effector cell degranulation in vitro and in vivo when artificially cross-linked, but not in the presence of the natural soluble antigen, suggesting that such an interaction will not trigger systemic anaphylaxis. Importantly, the anti-PSA IgE combined with PSA also triggers immune activation in vitro and in vivo and significantly prolongs the survival of human FcεRIα transgenic mice challenged with PSA-expressing tumors in a prophylactic vaccination setting. The anti-PSA IgE exhibits

  15. Molecular definition of multiple sites of antibody inhibition of malaria transmission-blocking vaccine antigen Pfs25.

    Science.gov (United States)

    Scally, Stephen W; McLeod, Brandon; Bosch, Alexandre; Miura, Kazutoyo; Liang, Qi; Carroll, Sean; Reponen, Sini; Nguyen, Ngan; Giladi, Eldar; Rämisch, Sebastian; Yusibov, Vidadi; Bradley, Allan; Lemiale, Franck; Schief, William R; Emerling, Daniel; Kellam, Paul; King, C Richter; Julien, Jean-Philippe

    2017-11-16

    The Plasmodium falciparum Pfs25 protein (Pfs25) is a leading malaria transmission-blocking vaccine antigen. Pfs25 vaccination is intended to elicit antibodies that inhibit parasite development when ingested by Anopheles mosquitoes during blood meals. The Pfs25 three-dimensional structure has remained elusive, hampering a molecular understanding of its function and limiting immunogen design. We report six crystal structures of Pfs25 in complex with antibodies elicited by immunization via Pfs25 virus-like particles in human immunoglobulin loci transgenic mice. Our structural findings reveal the fine specificities associated with two distinct immunogenic sites on Pfs25. Importantly, one of these sites broadly overlaps with the epitope of the well-known 4B7 mouse antibody, which can be targeted simultaneously by antibodies that target a non-overlapping site to additively increase parasite inhibition. Our molecular characterization of inhibitory antibodies informs on the natural disposition of Pfs25 on the surface of ookinetes and provides the structural blueprints to design next-generation immunogens.

  16. Novel flow cytometric analysis of the progress and route of internalization of a monoclonal anti-carcinoembryonic antigen (CEA) antibody.

    Science.gov (United States)

    Ford, C H; Tsaltas, G C; Osborne, P A; Addetia, K

    1996-03-01

    A flow cytometric method of studying the internalization of a monoclonal antibody (Mab) directed against carcinoembryonic antigen (CEA) has been compared with Western blotting, using three human colonic cancer cell lines which express varying amounts of the target antigen. Cell samples incubated for increasing time intervals with fluoresceinated or unlabelled Mab were analyzed using flow cytometry or polyacrylamide gel electrophoresis and Western blotting. SDS/PAGE analysis of cytosolic and membrane components of solubilized cells from the cell lines provided evidence of non-degraded internalized anti-CEA Mab throughout seven half hour intervals, starting at 5 min. Internalized anti-CEA was detected in the case of high CEA expressing cell lines (LS174T, SKCO1). Very similar results were obtained with an anti-fluorescein flow cytometric assay. Given that these two methods consistently provided comparable results, use of flow cytometry for the detection of internalized antibody is suggested as a rapid alternative to most currently used methods for assessing antibody internalization. The question of the endocytic route followed by CEA-anti-CEA complexes was addressed by using hypertonic medium to block clathrin mediated endocytosis.

  17. Characteristics Studies of 125I- and total PSA antibody's Binding with prostate specific antigen (PSA) in Human Uterus Tumors

    International Nuclear Information System (INIS)

    Al-Mudaffar, S.; Al-Salihi, J.

    2005-01-01

    Two groups of uterus tumors (benign and malignant) postmenopausal patients were used to investigate the presence of prostate specific antigen (PSA). Preliminary experiments were performed to follow the binding of '1 25 I-anti total PSA antibody with PSA in uterus tissues homogenates of the two groups with their corresponding antigen and found to be (8.8,7.1%) for benign and malignant tumors, respectively. An Immuno Radio Metric Assay (IRMA) procedure was developed for measuring PSA in benign and malignant uterus tumors homogenates. The optimum conditions of the binding of 125 I-anti total PSA antibody with PSA were as follows: PSA concentration (150,200 μg protein),tracer antibody concentration (125,250 μg protein), p H (7.6,7.2), temp (15,25?C) and time (1.5 hrs) for postmenopausal benign and malignant uterus tumors tissue homogenates, respectively. The use of different concentrations of Na + and Mg 2+ ions were shown to cause an increase in the binding at concentration of (125,75 mΜ) of Na 1+ ions (75,225 mΜ) of Mg 2+ ions for benign and malignant uterus tumors homogenates, respectively, while the use of different concentrations of urea and polyethylene glycol (PEG) Caused a decrease in the binding with the increase in the concentration of each of urea and PEG in the both cases

  18. Antibody Responses to Prostate-Associated Antigens in Patients with Prostatitis and Prostate Cancer

    Science.gov (United States)

    Maricque, Brett B.; Eickhoff, Jens C.; McNeel, Douglas G.

    2010-01-01

    Background An important focus of tumor immunotherapy has been the identification of appropriate antigenic targets. Serum-based screening approaches have led to the discovery of hundreds of tumor-associated antigens recognized by IgG. Our efforts to identify immunologically recognized proteins in prostate cancer have yielded a multitude of antigens, however prioritizing these antigens as targets for evaluation in immunotherapies has been challenging. In this report, we set out to determine whether the evaluation of multiple antigenic targets would allow the identification of a subset of antigens that are common immunologic targets in patients with prostate cancer. Methods Using a phage immunoblot approach, we evaluated IgG responses in patients with prostate cancer (n=126), patients with chronic prostatitis (n=45), and men without prostate disease (n=53). Results We found that patients with prostate cancer or prostatitis have IgG specific for multiple common antigens. A subset of 23 proteins was identified to which IgG were detected in 38% of patients with prostate cancer and 33% patients with prostatitis versus 6% of controls (pprostate and prostate cancer, and suggest that IgG responses to a panel of commonly recognized prostate antigens could be potentially used in the identification of patients at risk for prostate cancer or as a tool to identify immune responses elicited to prostate tissue. PMID:20632317

  19. Naturally acquired antibodies to Bacillus anthracis protective antigen in vultures of southern Africa

    Directory of Open Access Journals (Sweden)

    P. C.B. Turnbull

    2008-08-01

    Full Text Available TURNBULLP, P.C.B. DIEKMANNM,M., KILIAN, J.W., VERSFELDW, W.,DE VOS, V., ARNTZENL, L.,WOLTER, K., BARTELS, P. & KOTZE, A. 2008.N aturally acquired antibodies to Bacillusa nthracisp rotective antigeni n vultureso f southern Africa. Onderstepoort Journal of Veterinary Research, T5:95-102 Sera from 19 wild caught vultures in northern Namibia and 15 (12 wild caught and three captive bred but with minimal histories in North West Province, South Africa, were examined by an enzyme-linked immunosorbenats say( ELISAf or antibodiesto the Bacillus anthracis toxin protective antigen (PA. As assessed from the baseline established with a control group of ten captive reared vultures with well-documented histories, elevated titres were found in 12 of the 19 (63% wild caught Namibian birds as compared with none of the 15 South African ones. There was a highly significant difference between the Namibian group as a hole and the other groups (P 0.05. Numbers in the Namibian group were too small to determine any significances in species-, sex- or age-related differences within the raw data showing elevated titres in four out of six Cape Vultures, Gyps coprotheress, six out of ten Whitebacked Vultures, Gyps africanus, and one out of three Lappet-faced Vultures, Aegypiust racheliotus, or in five of six males versus three of seven females, and ten of 15 adults versus one of four juveniles. The results are in line with the available data on the incidence of anthrax in northern Namibia and South Africa and the likely contact of the vultures tested with anthrax carcasses. lt is not known whether elevated titre indicates infection per se in vultures or absorption of incompletely digested epitopes of the toxin or both. The results are discussed in relation to distances travelled by vultures as determined by new tracking techniques, how serology can reveal anthrax activity in an area and the issue of the role of vultures in transmission of anthrax.

  20. 99mTc-Labeling of Monoclonal Antibody to Carcinoembryonic Antigen and Biodistribution

    International Nuclear Information System (INIS)

    Moon, Dae Hyuk; Chung, June Key; Lee, Myu ng Chul; Koh, Chang Soon; Chung, Hong Keun; Park, Jae Gahb

    1992-01-01

    This study was designed to evaluate a direct method of 99m Tc labeling using β-mercaptoethanol as a reducing agent, and to investigate whether 99m Tc labeled specific monoclonal antibody against carcinoembryonic antigen (CEA-92) can be used for the scintigraphic localization of human colon cancer xenograft. Purified CEA-92 IgG was fragmented into F(ab') 2 and then labeled with 99m Tc by transchelation method using glucarate as a chelator. Labeling efficiency, immunological reactivity and in vitro stability of 99m Tc CEA-92 F(ab') 2 were measured and then injected intravenously into nude mice bearing human colon cancer (SNU-C4). Scintigrams were obtained at 24 hour after injection. Then nude mice were sacrificed and the radioactivity was measured. Labeling efficiency of injected 99m Tc CEA-92 F(ab') 2 , immunoreactive fraction and in vitro stability at 24 hour of injected 99m Tc CEA-92 F(ab') 2 was 45.2%, 32.8% and 57.4%, respectively. At 24 hour after injection, %ID/g in kidney (46.77) showed high uptake, but %ID/g in tumor (1.65) was significantly higher than spleen (0.69), muscle (0.16), intestine (0.45), stomach (0.75), heart (0.48) and blood(0.45). There was no significant difference between tumor and liver (1.81). Tumor contrast as quantitated by tumor to blood ratio of 99m Tc CEA-92 F(ab') 2 was increased significantly (p 131 I-CEA-92 F(ab') 2 . The scintigram demonstrated localization of radioactivity over transplanted tumor, but significant background radioactivity was also noted over kidney and abdomen. It is concluded that CEA-92 F(ab') 2 can be labeled with 99m Tc by a direct transchelation method using β-mercaptoethanol as a reducing agent and 99m Tc labeled CEA-92 F(ab') 2 can be used for the scintigraphic localization of human colon cancer xenograft in nude mice model.

  1. Anti-soluble liver antigen/liver-pancreas (SLA/LP) antibodies in pediatric patients with autoimmune hepatitis.

    Science.gov (United States)

    Vitozzi, Susana; Djilali-Saiah, Idriss; Lapierre, Pascal; Alvarez, Fernando

    2002-12-01

    Antibodies against soluble liver antigen/liver-pancreas (SLA/LP) have been associated with severe autoimmune hepatitis (AIH) and poor outcome, but most of these reports have focused on adult patients. The aim of this study was to assess the prevalence and clinical significance of anti-SLA/LP antibodies in a pediatric population with AIH. We developed a quantitative enzyme-linked immunoassay (ELISA), a Western blot (WB) and an immunoprecipitation assay (IPA) based on recombinant cDNA from activated Jurkat cells. The specificity of these tests was validated by testing 200 serum samples from healthy subjects, and from patients with liver and non-liver diseases. Anti-SLA/LP antibodies were found in patients with type 1 and type 2 AIH. The prevalence of these antibodies in patients with type 1 AIH was: 42% when tested by ELISA, 15% by WB and 50% by IPA. In patients with type 2 AIH, the prevalence rates were 42% by ELISA, 18% by WB and 44% by IPA. The mean titer values for anti-SLA/LP antibodies was significantly higher in type 2 AIH (1:1,300 +/- 339) than in type 1 AIH (1:600 +/- 71; p LKM1) and anti-liver cytosol type 1 (LC1) antibodies in sera. The presence of anti-SLA/LP showed a significant female preponderance in type 1 and 2 AIH patients (p = 0.0003 and p = 0.003, respectively), and was significantly correlated with a lower age at diagnosis (p = 0.05) in type 1 AIH patients. In conclusion, anti-SLA/LP antibodies in pediatric patients are associated with both type 1 and 2 AIH.

  2. 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

  3. 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.

  4. Seroprevalence of antibodies and antigens against hepatitis A-E viruses in refugees and asylum seekers in Germany in 2015.

    Science.gov (United States)

    Jablonka, Alexandra; Solbach, Philipp; Wöbse, Michael; Manns, Michael P; Schmidt, Reinhold E; Wedemeyer, Heiner; Cornberg, Markus; Behrens, Georg M N; Hardtke, Svenja

    2017-08-01

    Migration because of miscellaneous political crises in countries in the Middle East and Africa is a global challenge for whole Europe from an economic, social, and public health view. There is an urgent need to generate comprehensive, evidence-based data to expedite further screening and vaccination strategies. A total of 604 individuals ranging in age from 2 to 68 years who enrolled at a single reception center were tested for the prevalence of serologic markers for hepatitis virus types A, B, C, D, and E (HAV, HBV, HCV, HDV, HEV), respectively. Anti-HAV antibody prevalence was 91.2 and 70.3% in children younger than 18 years of age. The prevalence of anti-HEV antibodies was 20.1% among the individuals. 3.0% were positive for hepatitis B surface antigen, whereas 15.2% tested positive for anti-hepatitis B core antigen. None of the refugees tested positive for anti-HDV. 14.1% of refugees were vaccinated against hepatitis B and had a protective anti-hepatitis B surface level of at least 10 mIU/ml. Significant differences in vaccination status were found between the regions (Eastern Mediterranean Region with 77/482 (16.0%; 95% confidence interval=12.7-19.3%) versus African Region with 1/55 (1.8%; 95% confidence interval=0-5.0%). The prevalence of anti-HCV antibodies was 1.2% (n=7), with 0.7% HCV RNA positivity; 16.7% of hepatitis B surface antigen-positive individuals were HCV coinfected (n=3). The prevalence of refugees with previous exposure to hepatitis viruses was higher than that in the general German population, but lower than in other migrant populations in Germany. The vaccination status against hepatitis B was poor.

  5. Evaluation of the recombinant antigens Wb14 and WbT for the capture antibody diagnosis of lymphatic filariasis

    Directory of Open Access Journals (Sweden)

    André Filipe Pastor

    2018-03-01

    Full Text Available BACKGROUND Lymphatic filariasis (LF is a parasitic disease caused mainly by the Wuchereria bancrofti worm and that affects up to 120 million people worldwide. LF is the second cause of chronic global deformity, responsible for 15 million people with lymphedema (elephantiasis and 25 million men with scrotal hydrocele. Its diagnosis is still associated with numerous difficulties, such as the sample collection periods (microfilaria nocturnal periodicity and limited diagnostic kits. OBJECTIVES The aim of this work was to evaluate two recombinant antigens (Wb14 and WbT as part of an enzyme-linked immunosorbent assay (ELISA based antibody capture tests for LF. METHODS The recombinant antigens rWb14 and rWbT were expressed in Escherichia coli BL21 and an antibody capture ELISA was performed. For this, sera were used from microfilaremic individuals with W. bancrofti (MF, chronic pathology (CP, individuals infected with Strongyloides (SP and healthy controls from endemic (EN and non-endemic (NE areas. FINDINGS Both tests showed similar results, with 90% sensitivity and 96.6% specificity. In comparison with the BM14 ELISA commercial test, the Wb14 and WbT antigens performed with identical sensitivity but greater specificity. Reduced positivity with the CP suggested a potential to monitor cure. This was not confirmed, however, when sera from individuals up to seven years after treatment were assayed. MAIN CONCLUSIONS The Wb14 and WbT ELISAs were considered efficient and promising diagnostic tests. Due to the importance of antibody capture analysis to evaluate the Global Program to Eliminate Lymphatic Filariasis (GPELF, the tests proposed here appear as great alternatives to the available commercial system.

  6. 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.

  7. Arthrogenicity of type II collagen monoclonal antibodies associated with complement activation and antigen affinity

    OpenAIRE

    Koobkokkruad, Thongchai; Kadotani, Tatsuya; Hutamekalin, Pilaiwanwadee; Mizutani, Nobuaki; Yoshino, Shin

    2011-01-01

    Abstract Background The collagen antibody-induced arthritis (CAIA) model, which employs a cocktail of monoclonal antibodies (mAbs) to type II collagen (CII), has been widely used for studying the pathogenesis of autoimmune arthritis. In this model, not all mAbs to CII are capable of inducing arthritis because one of the initial events is the formation of collagen-antibody immune complexes on the cartilage surface or in the synovium, and subsequent activation of the complement by the complexes...

  8. Cerebral cysticercosis in a cat : clinical communication

    Directory of Open Access Journals (Sweden)

    E.V. Schwan

    2002-07-01

    Full Text Available The metacestode of Taenia solium, Cysticercus cellulosae, was recovered from the brain of a cat showing central nervous clinical signs ante mortem. This is the first record of cerebral cysticercosis in a cat in South Africa.

  9. RIA Quick, AUSRIA II-125, AUSAB. Comparative study on isolated and simultaneous radioimmunoassay of hepatitis B surface antigen and antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Kselikova, M; Urbankova, J [Institut fuer Haematologie und Bluttransfusion, Prag (Czechoslovakia)

    1983-01-01

    The surface antigen of hepatitis B (HBsAg) and the antibodies against HBsAg can be determined separately by the radioimmunoassay (RIA) test kits AUSRIA II-125 and AUSAB, respectively. Using the test kit RIA Quick (IMMUNO, Wien) it is possible to perform both the determinations in one preparation simultaneously. The sensitivity of RIA Quick for HBsAg corresponds to that of AUSRIA II-125 and for HBsAB it is considerably lower than that of AUSAB. RIA Quick is of excellent technical design and is by a quarter cheaper than the kits for isolated determination of HBsAg and HBsAb.

  10. Involvement of lymphocyte function-associated antigen-1 (LFA-1) in HIV infection: inhibition by monoclonal antibody

    DEFF Research Database (Denmark)

    Hansen, J E; Nielsen, C; Mathiesen, Lars Reinhardt

    1991-01-01

    Monoclonal antibodies (MAbs) against the alpha- and beta-chain of lymphocyte-associated antigen-1 (LFA-1) were examined for inhibition of HIV-1 infection in vitro. Infection of the T cell line MT4 and the monocytic cell line U937 by isolates HTLVIIIB and SSI-002, respectively was inhibited...... in a concentration dependent manner by MAb against the beta-chain but not against the alpha-chain. No cross-reactivity was found between MAb against LFA-1 and against the CD4 receptor (MAb Leu3a). MAbs against the beta-chain and the CD4 receptor were found to act synergistically in inhibiting HIV infection...

  11. Multiplex flow cytometry barcoding and antibody arrays identify surface antigen profiles of primary and metastatic colon cancer cell lines.

    Directory of Open Access Journals (Sweden)

    Kumar Sukhdeo

    Full Text Available Colon cancer is a deadly disease affecting millions of people worldwide. Current treatment challenges include management of disease burden as well as improvements in detection and targeting of tumor cells. To identify disease state-specific surface antigen signatures, we combined fluorescent cell barcoding with high-throughput flow cytometric profiling of primary and metastatic colon cancer lines (SW480, SW620, and HCT116. Our multiplexed technique offers improvements over conventional methods by permitting the simultaneous and rapid screening of cancer cells with reduced effort and cost. The method uses a protein-level analysis with commercially available antibodies on live cells with intact epitopes to detect potential tumor-specific targets that can be further investigated for their clinical utility. Multiplexed antibody arrays can easily be applied to other tumor types or pathologies for discovery-based approaches to target identification.

  12. Primary and secondary antibody reaction to acute radiation syndrome of calves after parenteral and oral immunization with Salmonella antigen

    International Nuclear Information System (INIS)

    Koch, F.; Mehlhorn, G.; Johannsen, U.; Panndorf, H.

    1984-01-01

    After active immunization against Salmonella dublin 25 calves (2.5 to 4 weeks old) were whole-body irradiated with sublethal to medium lethal X-ray doses, with 5 sham-irradiated control animals in each group. Sublethal and medium lethal doses failed in affecting the antibody titers in general, though short-time effects were observed temporarily. These depressive effects correlated with clinical responses, especially with reduced food intake probably caused by nutritive disorders. Higher antibody levels in the recovery period following sublethal and medium lethal doses indicate an antigenic stimulation released by the radiation syndrome. The depressive action of medium lethal doses on the booster response on the 30th postirradiation day refers to damage of the memory cell pool

  13. Dd-antigen-antibody system in five caste groups in north India.

    Science.gov (United States)

    Berry, V; Kaur, H

    1991-12-01

    Antigen Dd, a polymorphic antigen found in extracts of certain human dandruff specimens, was investigated in five caste groups of north India. The incidence of antigen Dd-positive type varied from 21.21 per cent in Brahmins to 29.08 per cent in the Jat Sikhs of Punjab. However, a high frequency (45%) was observed in the Sunni Muslims of Kashmir, which differed significantly, when compared with different caste groups of Punjab. Family studies on 44 families indicated its inherited nature, the mode of inheritance being autosomal dominant.

  14. Enzyme linked immunosorbent assay for the diagnosis of cerebral cysticercosis in Reunion island: comparison with computerized tomography scan

    Energy Technology Data Exchange (ETDEWEB)

    Michault, A; Coubes, P; Laporte, J P; Bouillan-Linet, E; Leroy, D

    1988-03-01

    An immunoenzymologic (Elisa) serodiagnosis of cysticercosis is evaluated in 75 encephalic cysticercotic patients whose diagnosis of the disease and its progression is assessed by tomodensitometry. A Taenia solium antigen is used. Only Ig G are investigated. The sensibility of serodiagnosis is 85 % and specificity 87 % when there is a progression of the disease; no difference is noticed in the patients without any progression of the disease and in control normal subjects. This serodiagnosis of cysticercosis appears of value for the evaluation of the activity of the disease.

  15. Muscular cysticercosis: Case report and imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Olmo, Neide Regina Simoes; Fiorio, Ulysses Ferreira; Clemente, Marcel Andreazza, E-mail: neideolmo@yahoo.com.br [Clinica Mult Imagem, Santos, SP (Brazil); Bastos, Eder Amaral [Universidade Metropolitana de Santos (UNIMES), Santos, SP (Brazil); Mendes, Gustavo Gomes [AC Camargo Cancer Center, Sao Paulo, SP (Brazil)

    2016-11-15

    Cysticercosis is a parasitic disease caused by a worm of the Cestoda class. The most prevalent form affects the nervous system. This case report is from a 78-year old female patient evaluated at Clinica Mult Imagem, in the city of Santos, Brazil, who presented a form of the disease that differed from the classic neurocysticercosis, in this case muscular cysticercosis. This and other forms of manifestation justify further studies to ensure adequate recognition, diagnosis and treatment of this parasitic disease. (author)

  16. The many faces of cysticercosis. Pictorial review

    Energy Technology Data Exchange (ETDEWEB)

    Rahalkar, M.D.; Shetty, D.D.; Kelkar, A.B.; Kelkar, A.A.; Kinare, A.S.; Ambardekar, S.T

    2000-09-01

    Cysticercosis in humans results from infestation with the larval stage of the parasite Cysticercus cellulosae of the tapeworm Taenia solium. Man normally acts as a definitive host. However, man can occasionally be the intermediate host, when cysticercosis becomes clinically manifest. Larvae lodge in the target organs, the brain, eyes, spine and skeletal muscles, where their appearances are highly suggestive or specific. We present a spectrum of such images, as encountered in Western India. Rahalkar, M.D. (2000)

  17. Control of Taenia solium taeniasis/cysticercosis

    DEFF Research Database (Denmark)

    Gabriël, Sarah; Dorny, Pierre; Mwape, Evans Kabemba

    2017-01-01

    Taenia solium taeniasis/cysticercosis is a neglected parasitic zoonosis with significant economic and public health impacts. Control measures can be broadly grouped into community health education, improvements in hygiene and sanitary conditions, proper meat handling at household and community...... or transmission. A feasible strategy to combat T. solium taeniasis/cysticercosis would include a combination of approaches focussing on both human (health education and treatment) and animal host (management, treatment and vaccination), which can vary for different communities and different geographical locations...

  18. 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.

  19. Sensitivity of hepatitis C virus core antigen and antibody combination assays in a global panel of window period samples

    Science.gov (United States)

    Laperche, Syria; Nubling, C. Micha; Stramer, Susan L.; Brojer, Ewa; Grabarczyk, Piotr; Yoshizawa, Hiroshi; Kalibatas, Vytenis; El Elkyabi, Magdy; Moftah, Faten; Girault, Annie; van Drimmelen, Harry; Busch, Michael P.; Lelie, Nico

    2016-01-01

    BACKGROUND Hepatitis C virus (HCV) antigen and antibody combination assays have been launched as a cost-effective alternative to nucleic acid testing (NAT) for reducing the antibody-negative window period (WP). Later, a HCV antigen chemiluminescence immunoassay (CLIA) became available. STUDY DESIGN AND METHODS A panel composed of 337 HCV NAT–yield samples that were characterized for viral load (VL) and genotype was used to compare the sensitivity of two combination enzyme-linked immunosorbent assays (Monolisa, Bio-Rad; and Murex, formerly Abbott) and a HCV antigen CLIA (Abbott). Analytic sensitivity was compared with HCV RNA detection using Ultrio (Grifols) by testing serial dilutions of 10 genotype (gt)1 to gt4 samples. RESULTS HCV antigen CLIA detected 92.4% of samples, whereas Monolisa and Murex detected 38.3 and 47.5%, respectively. In the HCV RNA VL range of 105 to 107 IU/mL, Monolisa and Murex detected 38% to 56% of gt1, 85% to 78% of gt2, and 21% to 37% of gt3. The overall geometric mean 50% limit of detection (range) of Ultrio on gt1 to gt4 dilution series was 3.5 (1.2–7.7) copies/mL, compared to 3.3 × 106 (4.4 × 105-2.7 × 107), 3.4 × 106 (2.2 × 105–4.2 × 107), and 2728 (415–7243) copies/mL for Monolisa, Murex, and HCV antigen CLIA, respectively. CONCLUSION Analytical sensitivity of NAT was on average 1 million- and 780-fold higher than combination assays and HCV antigen CLIA, respectively. Relative sensitivities of combination assays differed for genotypes with Murex being more sensitive for gt1 and gt3 and Monolisa more sensitive for gt2. Although being less sensitive than NAT, combination assays could be considered in resource-limited settings since they detect 38% to 47% of seronegative WP donations. PMID:26013970

  20. Fab antibody fragment-functionalized liposomes for specific targeting of antigen-positive cells

    Czech Academy of Sciences Publication Activity Database

    Ohradanova-Repic, A.; Nogueira, E.; Hartl, I.; Gomes, A.C.; Preto, A.; Steinhuber, E.; Muehlgrabner, V.; Repic, M.; Kuttke, M.; Zwirzitz, A.; Prouza, M.; Suchánek, M.; Wozniak-Knopp, G.; Hořejší, Václav; Schabbauer, G.; Cavaco-Paulo, A.; Stockinger, H.

    2018-01-01

    Roč. 14, č. 1 (2018), s. 123-130 ISSN 1549-9634 Institutional support: RVO:68378050 Keywords : Active targeting * Liposome functionalization * Immunoliposome * Antibody engineering * Recombinant Fab antibody fragment Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Cell biology Impact factor: 5.720, year: 2016

  1. Refining the LPS-Antigen in Salmonella Antibody Elisa for Poultry Enhanced Specificity without Impairing Sensitivity

    DEFF Research Database (Denmark)

    Lauritsen, Klara Tølbøl; Lind, Peter; Klausen, Joan

    2014-01-01

    In the Danish serological surveillance for Salmonella in poultry (serum and egg yolk) a mix-ELISA is used, based on S. typhimurium and S. enteritidis antigens (Feld et al., 2000). When we evaluated results of the test retrospectively, over the years an unacceptably large fraction of seropositive...... findings could not be confirmed by the subsequent confirmatory bacteriological sampling in the herd. Therefore we tried to enhance specificity of the ELISA, without losing sensitivity, by refining the antigens used....

  2. Epitope mapping of the carcinoembryonic antigen by monoclonal antibodies and establishment of a new improved radioimmunoassay system

    International Nuclear Information System (INIS)

    Kuroki, Masahide; Arakawa, Fumiko; Matsunaga, Akira; Okamoto, Naomi; Takakura, Kyoko; Matsuoka, Yuji; Higuchi, Hiroshi.

    1987-01-01

    A comprehensive mapping of epitopes on the carcinoembryonic antigen (CEA) molecule has been achieved by analyses of the specificities of 146 monoclonal antibodies (MAbs) from more than 300 hybridomas established recently. The reactivities of MAbs were analyzed by radio-immunoassays (RIA) with highly purified preparations of CEA and related antigens including normal fecal antigen-1 (NFA-1), NFA-2 in normal adult feces, nonspecific cross-reacting antigen (NCA) in lung and NCA-2 in meconium. The MAbs could be divided into five groups: group I, 23 clones directed to the NCA-common part of the CEA molecule; group II, 31 clones directed to the normal fecal cross-reacting antigen (NFCA)-common part; group III, 46 clones directed to the NFA-1-common part; group IV, 33 clones reactive with the heterogeneous carbohydrate part; and group V, 13 clones directed to the CEA-distinctive part which seemed to be highly specific for CEA. Mutual inhibitions of CEA binding between MAbs of the individual groups revealed that at least 25 different subgroups can be defined i.e., 4, 7, 8, 4, and 2 subgroups in groups I to V, respectively. The epitopes recognized by the group IV MAbs were found to be sensitive to oxidation with periodate, while the epitopes defined by MAbs of the other groups were resistant to this treatment. A solid-phase sandwich-type RIA system for CEA was established by using 2 MAbs from groups II and III as the CEA catcher and an MAb of group V as the tracer. This assay was shown to exhibit improved cancer-specificity and accuracy in the estimation of serum CEA levels. (author)

  3. Platelet transfusion refractoriness attributable to HLA antibodies produced by donor-derived cells after allogeneic bone marrow transplantation from one HLA-antigen-mismatched mother.

    Science.gov (United States)

    Hatakeyama, Naoki; Hori, Tsukasa; Yamamoto, Masaki; Inazawa, Natsuko; Iesato, Kotoe; Miyazaki, Toru; Ikeda, Hisami; Tsutsumi, Hiroyuki; Suzuki, Nobuhiro

    2011-12-01

    PTR is a serious problem in patients being treated for hematologic disorders. Two patients with acute leukemia developed PTR after allogeneic BMT from one HLA-antigen-mismatched mother attributable to HLA antibodies, which could not be detected in their serum before BMT. HLA antibodies, whose specificity resembled that of each patient, were detected in each donor's serum. Each donor had probably been immunized during pregnancy by their partner's HLA antigens expressed by the fetus, consequently, transplanted donor-derived cells provoked HLA antibodies in each recipient early after BMT, and those HLA antibodies induced PTR. If the mothers are selected as donors for their children, they should be tested for the presence of HLA antibodies. © 2010 John Wiley & Sons A/S.

  4. Antigenic Fingerprinting following Primary RSV Infection in Young Children Identifies Novel Antigenic Sites and Reveals Unlinked Evolution of Human Antibody Repertoires to Fusion and Attachment Glycoproteins.

    Directory of Open Access Journals (Sweden)

    Sandra Fuentes

    2016-04-01

    Full Text Available Respiratory Syncytial Virus (RSV is the major cause of pneumonia among infants. Here we elucidated the antibody repertoire following primary RSV infection and traced its evolution through adolescence and adulthood. Whole genome-fragment phage display libraries (GFPDL expressing linear and conformational epitopes in the RSV fusion protein (F and attachment protein (G were used for unbiased epitope profiling of infant sera prior to and following RSV infection. F-GFPDL analyses demonstrated modest changes in the anti-F epitope repertoires post-RSV infection, while G-GFPDL analyses revealed 100-fold increase in number of bound phages. The G-reactive epitopes spanned the N- and C-terminus of the G ectodomain, along with increased reactivity to the central conserved domain (CCD. Panels of F and G antigenic sites were synthesized to evaluate sera from young children (<2 yr, adolescents (14-18 yr and adults (30-45 yr in SPR real-time kinetics assays. A steady increase in RSV-F epitope repertoires from young children to adults was observed using peptides and F proteins. Importantly, several novel epitopes were identified in pre-fusion F and an immunodominant epitope in the F-p27. In all age groups, antibody binding to pre-fusion F was 2-3 folds higher than to post-fusion form. For RSV-G, antibody responses were high following early RSV infection in children, but declined significantly in adults, using either G proteins or peptides. This study identified unlinked evolution of anti-F and anti G responses and supportive evidence for immune pressure driven evolution of RSV-G. These findings could help development of effective countermeasures including vaccines.

  5. Dynamic interaction of 111indium-labeled monoclonal antibodies with surface antigens of solid tumors visualized in vivo by external scintigraphy

    International Nuclear Information System (INIS)

    Hwang, K.M.; Keenan, A.M.; Frincke, J.; David, G.; Pearson, J.; Oldham, R.K.; Morgan, A.C. Jr.

    1986-01-01

    Two 111 indium-labeled murine monoclonal antibodies (MoAb), D3 and 9.2.27, directed to tumor antigens of L-10 hepatocarcinoma and human melanoma, respectively, selectively localized antigen-positive target cells in guinea pigs and nude mice. The fate of MoAb differed in the two antigen-antibody systems after reacting with their corresponding tumor antigens in vivo as reflected by patterns of distribution and turnover in vivo. The 9.2.27 localized in melanoma xenograft in nude mice after intravenous administration with slow loss from tumor but more rapid loss from normal tissues and thus demonstrated optimal imaging of small tumors (approximately equal to 5 mm) between 3 and 6 days after injection of the radiolabeled antibody. In contrast, D3 demonstrated a biphasic localization in guinea pig L-10 hepatocarcinoma with a maximal activity on the 2d day after administration and showed rapid loss from both tumor and normal tissues. Nonspecific localization of antibodies in liver and in kidney was found both in syngeneic (nude mice) and xenogeneic (guinea pig) hosts but was more pronounced in the xenogeneic species. These results indicate that the nature of the antigen-antibody interaction may be of importance in selecting MoAb for both diagnosis and therapy of malignant diseases

  6. Seroprevalence of Antibodies against Plasmodium falciparum Sporozoite Antigens as Predictive Disease Transmission Markers in an Area of Ghana with Seasonal Malaria Transmission.

    Directory of Open Access Journals (Sweden)

    Kwadwo A Kusi

    Full Text Available As an increasing number of malaria-endemic countries approach the disease elimination phase, sustenance of control efforts and effective monitoring are necessary to ensure success. Mathematical models that estimate anti-parasite antibody seroconversion rates are gaining relevance as more sensitive transmission intensity estimation tools. Models however estimate yearly seroconversion and seroreversion rates and usually predict long term changes in transmission, occurring years before the time of sampling. Another challenge is the identification of appropriate antigen targets since specific antibody levels must directly reflect changes in transmission patterns. We therefore investigated the potential of antibodies to sporozoite and blood stage antigens for detecting short term differences in malaria transmission in two communities in Northern Ghana with marked, seasonal transmission.Cross-sectional surveys were conducted during the rainy and dry seasons in two communities, one in close proximity to an irrigation dam and the other at least 20 Km away from the dam. Antibodies against the sporozoite-specific antigens circumsporozoite protein (CSP and Cell traversal for ookinetes and sporozoites (CelTOS and the classical blood stage antigen apical membrane antigen 1 (AMA1 were measured by indirect ELISA. Antibody levels and seroprevalence were compared between surveys and between study communities. Antibody seroprevalence data were fitted to a modified reversible catalytic model to estimate the seroconversion and seroreversion rates.Changes in sporozoite-specific antibody levels and seroprevalence directly reflected differences in parasite prevalence between the rainy and dry seasons and hence the extent of malaria transmission. Seroconversion rate estimates from modelled seroprevalence data did not however support the above observation.The data confirms the potential utility of sporozoite-specific antigens as useful markers for monitoring short term

  7. Evaluation of Serum Specific Antibody against Recombinant ESAT-6 Antigen in Patients with Tuberculosis and Comparing to Normal Controls

    Directory of Open Access Journals (Sweden)

    Homeira Izadi

    2017-02-01

    Full Text Available Background & Objective: Tuberculosis (TB is a zoonotic disease which is caused by Mycobacterium tuberculosis. Because of common structural and secretory antigens between pathogen and nonpathogenic mycobacterium, the specific diagnosis of TB is difficult. Therefore, it is very important to find a new method with high specificity and sensitivity for accurate and rapid diagnosis of tuberculosis. In this study, the serodiagnostic potential of Mycobacterium tuberculosis recombinant ESAT-6 in TB infected patients was evaluated by Enzyme Linked Immunosorbent Assay (ELISA. Materials & Methods: 55 TB patients with active disease and 28 healthy controls have been collected and evaluated in different dilutions in ELISA methods for the presence of specific anti-ESAT-6 antibody. The specificity and the sensitivity of this method was compared with the culture test. Results: TB patients have high levels of specific antibody against ESAT-6 antigens. The specificity and the sensitivity of this method was calculated as 80.90% and 85.45%, respectively. Conclusion: These findings provide useful information on the importance of ESAT-6 protein and suggested this serologic test as a good alternative method for rapid and prefect diagnosis of tuberculosis.

  8. Maximum-Entropy Models of Sequenced Immune Repertoires Predict Antigen-Antibody Affinity

    DEFF Research Database (Denmark)

    Asti, Lorenzo; Uguzzoni, Guido; Marcatili, Paolo

    2016-01-01

    The immune system has developed a number of distinct complex mechanisms to shape and control the antibody repertoire. One of these mechanisms, the affinity maturation process, works in an evolutionary-like fashion: after binding to a foreign molecule, the antibody-producing B-cells exhibit a high...... of an HIV-1 infected patient. The Pearson correlation coefficient between our scoring function and the IC50 neutralization titer measured on 30 different antibodies of known sequence is as high as 0.77 (p-value 10-6), outperforming other sequence- and structure-based models....

  9. Changes in the repertoire of natural antibodies caused by immunization with bacterial antigens

    DEFF Research Database (Denmark)

    Shilova, N V; Navakouski, M J; Huflejt, M

    2011-01-01

    The repertoire of natural anti-glycan antibodies in naïve chickens and in chickens immunized with bacteria Burkholderia mallei, Burkholderia pseudomallei, and Francisella tularensis as well as with peptides from an outer membrane protein of B. pseudomallei was studied. A relatively restricted pat...... pattern of natural antibodies (first of all IgY against bacterial cell wall peptidoglycan fragments, L-Rha, and core N-acetyllactosamine) shrank and, moreover, the level of detectable antibodies decreased as a result of immunization....

  10. Augmentation of the antibody response of Atlantic salmon by oral administration of alginate-encapsulated IPNV antigens.

    Directory of Open Access Journals (Sweden)

    Lihan Chen

    Full Text Available The objective of the present study was to assess the effect of alginate-encapsulated infectious pancreatic necrosis virus antigens in inducing the immune response of Atlantic salmon as booster vaccines. One year after intraperitoneal injection with an oil-adjuvanted vaccine, post-smolts were orally boosted either by 1 alginate-encapsulated IPNV antigens (ENCAP; 2 soluble antigens (UNENCAP or 3 untreated feed (control. This was done twice, seven weeks apart. Sampling was done twice, firstly at 7 weeks post 1st oral boost and the 2nd, at 4 weeks after the 2nd oral boost. Samples included serum, head kidney, spleen and hindgut. Serum antibodies were analyzed by ELISA while tissues were used to assess the expression of IgM, IgT, CD4, GATA3, FOXP3, TGF-β and IL-10 genes by quantitative PCR. Compared to controls, fish fed with ENCAP had a significant increase (p<0.04 in serum antibodies following the 1st boost but not after the 2nd boost. This coincided with significant up-regulation of CD4 and GATA3 genes. In contrast, serum antibodies in the UNENCAP group decreased both after the 1st and 2nd oral boosts. This was associated with significant up-regulation of FOXP3, TGF-β and IL-10 genes. The expression of IgT was not induced in the hindgut after the 1st oral boost but was significantly up-regulated following the 2nd one. CD4 and GATA3 mRNA expressions exhibited a similar pattern to IgT in the hindgut. IgM mRNA expression on the other hand was not differentially regulated at any of the times examined. Our findings suggest that 1 Parenteral prime with oil-adjuvanted vaccines followed by oral boost with ENCAP results in augmentation of the systemic immune response; 2 Symmetrical prime and boost (mucosal with ENCAP results in augmentation of mucosal immune response and 3 Symmetrical priming and boosting (mucosal with soluble antigens results in the induction of systemic immune tolerance.

  11. Possible role of specific immunoglobulin M antibodies to Plasmodium falciparum antigens in immunoprotection of humans living in a hyperendemic area, Burkina Faso

    DEFF Research Database (Denmark)

    Boudin, C; Chumpitazi, B; Dziegiel, M

    1993-01-01

    of antibodies to crude extracts of Plasmodium falciparum (IgG or IgM antisomatic and IgG antiexoantigens) were tested by IFI or enzyme-linked immunosorbent assay and were followed up according to the fluctuations of the parasite densities. Specific IgG antibodies had the same evolution as parasite densities....... Group 3 was composed of immunoprotected adults. Specific IgM and IgG antibodies to crude extracts or a recombinant antigen (glutamate-rich protein) of P. falciparum were tested. Specific IgM antibodies were lower in group 1 (nonimmune) than in groups 2 (semiimmune) and 3 (immunoprotected). Furthermore...

  12. Monoclonal antibodies to murine thrombospondin-1 and thrombospondin-2 reveal differential expression patterns in cancer and low antigen expression in normal tissues

    International Nuclear Information System (INIS)

    Bujak, Emil; Pretto, Francesca; Ritz, Danilo; Gualandi, Laura; Wulhfard, Sarah; Neri, Dario

    2014-01-01

    There is a considerable interest for the discovery and characterization of tumor-associated antigens, which may facilitate antibody-based pharmacodelivery strategies. Thrombospondin-1 and thrombospondin-2 are homologous secreted proteins, which have previously been reported to be overexpressed during remodeling typical for wound healing and tumor progression and to possibly play a functional role in cell proliferation, migration and apoptosis. To our knowledge, a complete immunohistochemical characterization of thrombospondins levels in normal rodent tissues has not been reported so far. Using antibody phage technology, we have generated and characterized monoclonal antibodies specific to murine thrombospondin-1 and thrombospondin-2, two antigens which share 62% aminoacid identity. An immunofluorescence analysis revealed that both antigens are virtually undetectable in normal mouse tissues, except for a weak staining of heart tissue by antibodies specific to thrombospondin-1. The analysis also showed that thrombospondin-1 was strongly expressed in 5/7 human tumors xenografted in nude mice, while it was only barely detectable in 3/8 murine tumors grafted in immunocompetent mice. By contrast, a high-affinity antibody to thrombospondin-2 revealed a much lower level of expression of this antigen in cancer specimens. Our analysis resolves ambiguities related to conflicting reports on thrombosponding expression in health and disease. Based on our findings, thrombospondin-1 (and not thrombospondin-2) may be considered as a target for antibody-based pharmacodelivery strategies, in consideration of its low expression in normal tissues and its upregulation in cancer. - Highlights: • High affinity monoclonal antibodies to murine and human TSP1 and 2 were raised. • Both antigens are virtually undetectable in normal mouse tissues. • Strong positivity of human tumor xenografts for TSP1 was detected. • Study revealed much lower level of TSP2 expression in cancer specimens

  13. Monoclonal antibodies to murine thrombospondin-1 and thrombospondin-2 reveal differential expression patterns in cancer and low antigen expression in normal tissues

    Energy Technology Data Exchange (ETDEWEB)

    Bujak, Emil [Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology (ETH Zürich), Vladimir-Prelog-Weg 2, CH-8093 Zurich (Switzerland); Pretto, Francesca; Ritz, Danilo; Gualandi, Laura; Wulhfard, Sarah [Philochem AG, Libernstrasse 3, CH-8112 Otelfingen (Switzerland); Neri, Dario, E-mail: neri@pharma.ethz.ch [Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology (ETH Zürich), Vladimir-Prelog-Weg 2, CH-8093 Zurich (Switzerland)

    2014-09-10

    There is a considerable interest for the discovery and characterization of tumor-associated antigens, which may facilitate antibody-based pharmacodelivery strategies. Thrombospondin-1 and thrombospondin-2 are homologous secreted proteins, which have previously been reported to be overexpressed during remodeling typical for wound healing and tumor progression and to possibly play a functional role in cell proliferation, migration and apoptosis. To our knowledge, a complete immunohistochemical characterization of thrombospondins levels in normal rodent tissues has not been reported so far. Using antibody phage technology, we have generated and characterized monoclonal antibodies specific to murine thrombospondin-1 and thrombospondin-2, two antigens which share 62% aminoacid identity. An immunofluorescence analysis revealed that both antigens are virtually undetectable in normal mouse tissues, except for a weak staining of heart tissue by antibodies specific to thrombospondin-1. The analysis also showed that thrombospondin-1 was strongly expressed in 5/7 human tumors xenografted in nude mice, while it was only barely detectable in 3/8 murine tumors grafted in immunocompetent mice. By contrast, a high-affinity antibody to thrombospondin-2 revealed a much lower level of expression of this antigen in cancer specimens. Our analysis resolves ambiguities related to conflicting reports on thrombosponding expression in health and disease. Based on our findings, thrombospondin-1 (and not thrombospondin-2) may be considered as a target for antibody-based pharmacodelivery strategies, in consideration of its low expression in normal tissues and its upregulation in cancer. - Highlights: • High affinity monoclonal antibodies to murine and human TSP1 and 2 were raised. • Both antigens are virtually undetectable in normal mouse tissues. • Strong positivity of human tumor xenografts for TSP1 was detected. • Study revealed much lower level of TSP2 expression in cancer specimens

  14. MR Imaging in intramedullary cysticercosis

    Energy Technology Data Exchange (ETDEWEB)

    Parmar, H.; Patwardhan, V.; Patankar, T.; Prasad, S. [Dept. of Radiology, King Edward VII Memorial Hospital, Parel, Mumbai (India); Shah, J.; Patkar, D. [Dept. of Radiology, Dr. Balabhai Nanavati Hospital and Research Center, Mumbai (India); Castillo, M. [Dept. of Neuroradiology, Univ. of North Carolina (United States)

    2001-11-01

    Although intramedullary spinal cord cysticercosis (IMC) is uncommon, its presence is being increasingly recognised by magnetic resonance imaging. We studied six patients from an endemic region and present the MRI features and clinical correlation of IMC. Six patients who presented with para- or quadriplegia were studied by contrast enhanced spinal MRI. Prompted by the spinal lesions, all patients underwent brain MRI. Clinical data and laboratory studies were reviewed in all patients. Definite diagnosis was established in the form of response to drug therapy (n=4) and histopathology (n=2). Follow-up MRI studies of spine and brain were obtained in four patients 2 months after they started medical treatment, regardless of surgery. Five patients showed fusiform and focal enlargement of the spinal cord (cervical 2, thoracic 3). Well-defined cysts with a slightly hyperintense mural nodule were identified in five patients in T1-weighted images (T1WI). All cysts were hyperintense on T2WI and merged with the surrounding oedema. Oedema extended one to three vertebral levels above or below the cyst. Post-contrast T1WI showed well-defined, ring enhancing lesions with smooth walls in all patients. Symptoms in all patients correlated with the level of the lesions. Brain studies demonstrated lesions in just two patients. Histopathological confirmation was obtained in two patients. Follow-up spinal MRI was normal in two patients, following 2 months of treatment while residual and smaller lesions were seen in two patients. Two patients were asymptomatic and denied follow-up MRI. MRI of spinal cysticercosis were typical of and similar to those seen in cerebral lesions in our patients and corresponded to the level of symptoms. All cysts were surrounded by oedema. Two of four patients showed residual lesions after 2 months of therapy and 33% of patients showed concomitant intracranial lesions. (orig.)

  15. MR Imaging in intramedullary cysticercosis

    International Nuclear Information System (INIS)

    Parmar, H.; Patwardhan, V.; Patankar, T.; Prasad, S.; Shah, J.; Patkar, D.; Castillo, M.

    2001-01-01

    Although intramedullary spinal cord cysticercosis (IMC) is uncommon, its presence is being increasingly recognised by magnetic resonance imaging. We studied six patients from an endemic region and present the MRI features and clinical correlation of IMC. Six patients who presented with para- or quadriplegia were studied by contrast enhanced spinal MRI. Prompted by the spinal lesions, all patients underwent brain MRI. Clinical data and laboratory studies were reviewed in all patients. Definite diagnosis was established in the form of response to drug therapy (n=4) and histopathology (n=2). Follow-up MRI studies of spine and brain were obtained in four patients 2 months after they started medical treatment, regardless of surgery. Five patients showed fusiform and focal enlargement of the spinal cord (cervical 2, thoracic 3). Well-defined cysts with a slightly hyperintense mural nodule were identified in five patients in T1-weighted images (T1WI). All cysts were hyperintense on T2WI and merged with the surrounding oedema. Oedema extended one to three vertebral levels above or below the cyst. Post-contrast T1WI showed well-defined, ring enhancing lesions with smooth walls in all patients. Symptoms in all patients correlated with the level of the lesions. Brain studies demonstrated lesions in just two patients. Histopathological confirmation was obtained in two patients. Follow-up spinal MRI was normal in two patients, following 2 months of treatment while residual and smaller lesions were seen in two patients. Two patients were asymptomatic and denied follow-up MRI. MRI of spinal cysticercosis were typical of and similar to those seen in cerebral lesions in our patients and corresponded to the level of symptoms. All cysts were surrounded by oedema. Two of four patients showed residual lesions after 2 months of therapy and 33% of patients showed concomitant intracranial lesions. (orig.)

  16. Antibodies to AB blood group antigens mimic anti-salivary duct autoantibodies in patients with limited sicca symptoms.

    Science.gov (United States)

    Goldblatt, F; Beroukas, D; Gillis, D; Cavill, D; Bradwell, A; Rischmueller, M; Gordon, T P

    2000-10-01

    We evaluated the clinical relevance and pathogenic significance of anti-salivary duct autoantibodies (ASDA) in Sjögren's syndrome (SS) and rheumatoid arthritis (RA) by examining (1) their frequency in healthy controls, patients with sicca symptoms, and patients with various autoimmune and infective disorders; (2) their localization by confocal microscopy; and (3) their tissue distribution and cross reactivity with blood group antigens. Indirect immunofluorescence (IF) was performed on commercial cryostat sections of monkey parotid salivary gland. Sections were examined by fluorescence and confocal laser scanning microscopy. Sera giving positive staining on the ducts were tested by IF on a range of monkey tissues and salivary glands from several mammalian species. Blocking experiments were performed with human erythrocytes of different ABO blood groups and AB antigens. We identified 2 distinct ductal staining patterns. The first resembled ASDA described in earlier studies and showed patchy bright staining of the apical (luminal) surfaces of the ducts and staining of apical cytoplasmic vesicles. The other was only observed with anti-mitochondrial antibody positive sera and stained the mitochondrial-rich ductal epithelium in a distinctive punctate pattern. Antibodies staining the apical surface of ducts were detected rarely in patients with antiRo/La autoantibody-positive primary SS (1/76) and RA (1/36) and were found in only 1115 with RA and secondary SS. ASDA were detected in sera from 13/51 (25.5%) of patients referred to our clinic with limited sicca symptoms who were anti-Ro/La antibody-negative and had no typical clinical or laboratory features of classical primary SS. The apical ductal staining pattern was not observed with sera from 63 healthy controls without sicca symptoms or in patients with autoimmune and infective disorders. Twelve of the 13 patients whose sera gave ASDA-like staining were blood group O and one group A. Ductal staining was abolished in

  17. 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.

  18. Identification of a novel dendritic cell surface antigen defined by carbohydrate specific CD24 antibody cross-reactivity.

    Science.gov (United States)

    Williams, L A; McLellan, A D; Summers, K L; Sorg, R V; Fearnley, D B; Hart, D N

    1996-01-01

    Dendritic cells (DC) are characterized as leucocytes that lack mature lineage specific markers and stimulate naive T-lymphocyte proliferation in vitro and in vivo. The mouse heat stable antigen (HSA) participates in T lymphocyte co-stimulation and is expressed by DC isolated from thymus, skin and spleen. The human HSA homologue, CD24, is predominantly expressed by B lymphocytes and granulocytes, but its expression on DC has not been studied in detail. CD24 clearly participates in B-lymphocyte signalling but co-stimulatory activity for T lymphocytes has not yet been described. We have examined the expression of CD24 on human peripheral blood DC populations isolated directly or following in vitro culture. The CD24 antigen was absent from blood DC however, cross-reactive sialylated carbohydrate epitopes were detected on DC with some CD24 monoclonal antibodies (mAb). These CD24 mAb define a protein surface antigen, which is expressed by an immature or resting subpopulation of peripheral blood DC and is down-regulated following activation differentiation in vitro. PMID:8911149

  19. Cell proliferation-associated nuclear antigen defined by antibody Ki-67: a new kind of cell cycle-maintaining proteins

    International Nuclear Information System (INIS)

    Duchrow, M.; Schlueter, C.; Key, G.; Kubbutat, H.G.; Wohlenberg, C.; Flad, H.D.; Gerdes

    1995-01-01

    A decade of studies on the human nuclear antigen defined by monoclonal antibody Ki-67 (the 'Ki-67 proteins') has made it abundantly clear that this structure is strictly associated with human cell proliferation and the expression of this protein can be used to access the growth fraction of a given cell population. Until recently the Ki-67 protein was described as a nonhistone protein that is highly susceptible to protease treatment. We have isolated and sequenced cDNAs encoding for this antigen and found two isoforms of the full length cDNA of 11.5 and 12.5 kb, respectively, sequence and structure of which are thus far unique. The gene encoding the Ki-67 protein is organized in 15 exons and is localized on chromosome 10. The center of this gene is formed by an extraordinary 6845 bp exon containing 16 successively repeated homologous segments of 366 bp ('Ki-67 repeats'), each containing a highly conserved new motif of 66 bp ('Ki-67 motif'). The deduced peptide sequence of this central exon possesses 10 ProGluSerThr (PEST) motifs which are associated with high turnover proteins such as other cell cycle-related proteins, oncogenes and transcription factors, etc. Like the latter proteins the Ki-67 antigen plays a pivotal role in maintaining cell proliferation because Ki-67 protein antisense oligonucleotides significantly inhibit 3 H-thymidine incorporation in permanent human tumor cell lines in a dose-dependent manner. (author). 30 refs, 2 figs

  20. 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.

  1. [Monoclonal antibodies ICO-02 to blast cell antigens in patients with chronic myeloleukemia in blast crisis].

    Science.gov (United States)

    Baryshnikov, A Iu

    1984-01-01

    Mice were immunized with blood cells of a patient with chronic granulocytic leukemia, and their cells were subsequently used for the preparation of hybridoma ICO-02. This hybridoma is continuously producing monoclonal antibodies which reacted with cells in 4 out of 13 patients with blastic crisis of chronic granulocytic leukemia and in 6 out of 38 patients with acute lymphoblastic leukemia. Antibodies reacted with blast cells in 2 out of 3 patients with undifferentiated blastic crisis of chronic myelocytic leukemia and in 2 out of 5 patients with lymphoid variant of blastic crisis of chronic granulocytic leukemia. Cells of 6 patients with acute lymphoblastic leukemia which reacted with the monoclonal antibodies had immunological markers of T lymphocytes bone-marrow precursors. Monoclonal antibodies did not react with cells of blood and bone marrow from healthy people and from patients with chronic lymphocytic leukemia, acute myeloblastic leukemia, acute myelomonocytic leukemia, acute monoblastic leukemia and lymphosarcoma.

  2. THE EFFECT OF SALICYLATES ON THE PRECIPITATION OF ANTIGEN WITH ANTIBODY.

    Science.gov (United States)

    Coburn, A F; Kapp, E M

    1943-02-01

    1. Sodium salicylate modifies the precipitation of normal rabbit serum protein by sodium tungstate, and partially inhibits the precipitation of horse serum euglobulin by rabbit antiserum. Sodium salicylate added to a system containing crystalline egg albumin and its antibody partly prevents the formation of precipitate, the degree of inhibition being related to the concentration of salicylate. 2. Precipitation in the equivalence zone is more readily prevented by salicylate than precipitation in the region of antibody excess, the immune system becoming progressively less sensitive to the action of salicylate as the excess of antibody becomes larger. 3. Formed precipitates were partly dissolved following resuspension in the presence of salicylate. 4. The salicylate effect on immune precipitation is reversible, and appears to be due to inactivation of antibody. 5. Salicylate was more effective in preventing specific precipitation than other anions of a lyotropic series tested.

  3. Conformational Heterogeneity in Antibody-Protein Antigen Recognition IMPLICATIONS FOR HIGH AFFINITY PROTEIN COMPLEX FORMATION

    Czech Academy of Sciences Publication Activity Database

    Addis, P. W.; Hall, c. J.; Bruton, S.; Veverka, Václav; Wilkinson, I. C.; Muskett, F. W.; Renshaw, P. S.; Prosser, C. E.; Carrington, B.; Lawson, A. D. G.; Griffin, R.; Taylor, R. J.; Waters, L. C.; Henry, A. J.; Carr, M. D.

    2014-01-01

    Roč. 289, č. 10 (2014), s. 7200-7210 ISSN 0021-9258 Institutional support: RVO:61388963 Keywords : NMR * antibody * protein-protein interaction * protein conformation Subject RIV: CE - Biochemistry Impact factor: 4.573, year: 2014

  4. Dog erythrocyte antigens (DEA) 1, 4, 7 and suspected naturally occurring anti-DEA 7 antibodies in Italian Corso dogs.

    Science.gov (United States)

    Spada, E; Proverbio, D; Priolo, V; Ippolito, D; Baggiani, L; Perego, R; Pennisi, M G

    2017-04-01

    We sought to determine the prevalence of dog erythrocyte antigen (DEA) 1, 4 and 7 and naturally occurring anti-DEA7 antibodies in Italian Corso dogs. In addition, we correlated DEAs with different epidemiologic variables, compared the prevalence of DEAs against other canine populations and assessed the risk of sensitisation and transfusion reactions (TRs) following unmatched transfusion. Blood samples from 100 Corso dogs were evaluated for DEA 1, 4, 7 and naturally occurring anti-DEA 7 antibodies. Seventy-one percent of samples were DEA 1-negative, 100% tested DEA 4-positive, and 95% tested DEA 7-negative. Suspected anti-DEA7 antibodies were found in 32% dogs. The DEA 1 and 7-negative phenotypes were significantly more common than in most canine populations. When a previously tested Italian canine population was considered as blood donors for Corso dogs, the risk of DEA 1 sensitisation using DEA 1 untyped blood was 29%, and of acute haemolytic TRs after a second untyped DEA 1-incompatible transfusion was 8%. The potential for delayed TRs between DEA 7-negative Corso dogs with suspected naturally occurring anti-DEA 7 antibodies receiving untyped DEA 7-positive blood was 11%. Conversely, when Corso dogs were blood donors for the same population, the risk of DEA 1 sensitisation was 17% and the risk of an acute haemolytic TR after a second DEA 1-incompatible blood transfusion was 3%. Corso dogs can be suitable blood donors. Additional studies are needed to clarify whether the high prevalence of naturally occurring anti-DEA 7 antibodies in this breed could increase their risk of delayed TRs when they are blood recipients. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Antibody tumor penetration: transport opposed by systemic and antigen-mediated clearance.

    Science.gov (United States)

    Thurber, Greg M; Schmidt, Michael M; Wittrup, K Dane

    2008-09-01

    Antibodies have proven to be effective agents in cancer imaging and therapy. One of the major challenges still facing the field is the heterogeneous distribution of these agents in tumors when administered systemically. Large regions of untargeted cells can therefore escape therapy and potentially select for more resistant cells. We present here a summary of theoretical and experimental approaches to analyze and improve antibody penetration in tumor tissue.

  6. Trichinella britovi human infection in Spain : antibody response to surface, excretory/secretory and somatic antigens

    Directory of Open Access Journals (Sweden)

    Rodríguez-Osorio M.

    2003-06-01

    Full Text Available A third outbreak of Trichinella britovi with 140 people involved, occurred in Granada Spain (December 1998. The source of infection was sausage made from uninspected wild boar meat. Fifty-two patients agreed to participated in this study. An elevated eosinophil level (> 5 % was detected in 59.6 % of patients, and persisted in most of these cases for two months. A moderate IgG response was observed. At the onset of symptoms, Western blot (WB test detected more positive cases than Enzyme linked immunosorbent assay (ELISA and indirect immunofluorescence (IIF. Six months from infection, ELISA revealed fewer positive cases than the other two tests. It would appear that the response to somatic antigens starts earlier than those to cuticular and excretory/secretory (ES antigens and that the response to ES antigens is the first to decrease.

  7. Characterization of sporozoite surface antigens of Plasmodium falciparum, using monoclonal antibodies. Part of a coordinated programme on the preparation of irradiated vaccines against some human diseases

    International Nuclear Information System (INIS)

    Groot, M.

    1982-10-01

    Sporozoites are considered as a source of potential vaccine. Characterization of their antigens is therefore important and can be achieved by monoclonal antibodies. The purpose of this project is to study the production of monoclonal antibodies against sporozoites of P. falciparum. Various infections of mosquitoes were carried out during the period 1981-1982 to obtain antigens for the production of hybridomas. Hybridomas were produced from mice immunized through the bites of infected mosquitoes and by intravenous inoculation. The anti-sporozoite activity of the hybridomas was tested by an immunofluorescent antibody test using P. falciparum sporozoites as antigens. Positive immunofluorescence was seen in hybridoma cell lines tested with P. falciparum, whereas negative results were obtained when the cell lines were cross-reacted with other human species (P. vivax) and with a rodent malaria parasite (P. berghei)

  8. Geographical and temporal conservation of antibody recognition of Plasmodium falciparum variant surface antigens

    DEFF Research Database (Denmark)

    Nielsen, Morten A; Vestergaard, Lasse S; Lusingu, John

    2004-01-01

    The slow acquisition of protection against Plasmodium falciparum malaria probably reflects the extensive diversity of important antigens. The variant surface antigens (VSA) that mediate parasite adhesion to a range of host molecules are regarded as important targets of acquired protective immunity......, but their diversity makes them questionable vaccine candidates. We determined levels of VSA-specific immunoglobulin G (IgG) in human plasma collected at four geographically distant and epidemiologically distinct localities with specificity for VSA expressed by P. falciparum isolates from three African countries...

  9. Antibody isotype responses to egg antigens in human chronic Schistosomiasis mansoni before and after treatment

    Directory of Open Access Journals (Sweden)

    Gomes Yara M

    2002-01-01

    Full Text Available In the present communication we analyzed the levels of IgG1, IgG2, IgG3, IgG4 and IgE isotypes to soluble egg antigen of Schistosoma mansoni by ELISA in individuals from an endemic area for schistosomiasis in Northeast Brazil. The analysis was performed before and after treatment to evaluate the age-dependent pattern, and to identify differences in the reactivities to antigens. Our results suggest that schistosomiasis treatment would not interfere with this sort of immune response.

  10. Conserved epitope on several human vitamin K-dependent proteins: location of the antigenic site and influence of metal ions on antibody binding

    International Nuclear Information System (INIS)

    Church, W.R.; Messier, T.; Howard, P.R.; Amiral, J.; Meyer, D.; Mann, K.G.

    1988-01-01

    A murine monoclonal antibody (designated H-11) produced by injecting mice with purified human protein C was found to bind several human vitamin K-dependent proteins. Using a solid-phase competitive radioimmunoassay with antibody immobilized onto microtiter plates, binding of 125 I-labeled protein C to the antibody was inhibited by increasing amounts of protein C, prothrombin, and Factors X and VII over a concentration range of 1 x 10 -8 to 1 x 10 -6 M. Chemical treatment of prothrombin with a variety of agents did not destroy the antigenic site recognized by the antibody as measured by immunoblotting of prothrombin or prothrombin derivative immobilized onto nitrocellulose. Immunoblotting of purified vitamin K-dependent polypeptides with the monoclonal antibody following sodium dodecyl sulfate-polyacrylamide gel electrophoresis and electrophoretic transfer to nitrocellulose indicated that the antigenic site was found on the light chains of protein C and Factor X. The exact location of the antigenic determinant for antibody H-11 was established using synthetic peptides. Comparison of protein sequences of bovine and human vitamin K-dependent proteins suggests that the sequence Phe-Leu-Glu-Glu-Xaa-Arg/Lys is required for antibody binding. Increasing concentrations of Ca 2+ , Mg 2+ , or Mn 2+ partially inhibited binding of 125 I-protein C to the antibody in a solid-phase assay system with half-maximal binding observed at divalent metal ion concentrations of 2, 4, and 0.6 mM, respectively. The antigenic site thus recognized by monoclonal antibody H-11 is located at the amino-terminal region in the highly conserved γ-carboxyglutamic acid-containing domains of several, but not all, vitamin K-dependent proteins

  11. Use of thermodynamic coupling between antibody-antigen binding and phospholipid acyl chain phase transition energetics to predict immunoliposome targeting affinity.

    Science.gov (United States)

    Klegerman, Melvin E; Zou, Yuejiao; Golunski, Eva; Peng, Tao; Huang, Shao-Ling; McPherson, David D

    2014-09-01

    Thermodynamic analysis of ligand-target binding has been a useful tool for dissecting the nature of the binding mechanism and, therefore, potentially can provide valuable information regarding the utility of targeted formulations. Based on a consistent coupling of antibody-antigen binding and gel-liquid crystal transition energetics observed for antibody-phosphatidylethanolamine (Ab-PE) conjugates, we hypothesized that the thermodynamic parameters and the affinity for antigen of the Ab-PE conjugates could be effectively predicted once the corresponding information for the unconjugated antibody is determined. This hypothesis has now been tested in nine different antibody-targeted echogenic liposome (ELIP) preparations, where antibody is conjugated to dipalmitoylphosphatidylethanolamine (DPPE) head groups through a thioether linkage. Predictions were satisfactory (affinity not significantly different from the population of values found) in five cases (55.6%), but the affinity of the unconjugated antibody was not significantly different from the population of values found in six cases (66.7%), indicating that the affinities of the conjugated antibody tended not to deviate appreciably from those of the free antibody. While knowledge of the affinities of free antibodies may be sufficient to judge their suitability as targeting agents, thermodynamic analysis may still provide valuable information regarding their usefulness for specific applications.

  12. Antigen-specific immature dendritic cell vaccine ameliorates anti-dsDNA antibody-induced renal damage in a mouse model.

    Science.gov (United States)

    Xia, Yumin; Jiang, Shan; Weng, Shenhong; Lv, Xiaochun; Cheng, Hong; Fang, Chunhong

    2011-12-01

    Dendritic cells (DCs) can inhibit immune response by clonal anergy when immature. Recent studies have shown that immature DCs (iDCs) may serve as a live cell vaccine after specific antigen pulse based on its potential of blocking antibody production. In this study, we aimed to investigate the effects of nuclear antigen-pulsed iDCs in the treatment of lupus-like renal damages induced by anti-dsDNA antibodies. iDCs were generated from haemopoietic stem cells in bone marrow and then pulsed in vitro with nuclear antigen. The iDC vaccine and corresponding controls were injected into mice with lupus-like renal damages. The evaluation of disease was monitored by biochemical parameters and histological scores. Anti-dsDNA antibody isotypes and T-lymphocyte-produced cytokines were analysed for elucidating therapeutic mechanisms. RESULTS; The mice treated with antigen-pulsed iDCs had a sustained remission of renal damage compared with those injected with non-pulsed iDCs or other controls, including decreased anti-dsDNA antibody level, less proteinuria, lower blood urea nitrogen and serum creatinine values, and improved histological evaluation. Analysis on isotypes of anti-dsDNA antibody showed that iDC vaccine preferentially inhibited the production of IgG3, IgG2b and IgG2a. Furthermore, administration of antigen-treated iDCs to mice resulted in significantly reduced IL-2, IL-4 and IL-12 and IFN-γ produced by T-memory cells. Conversely, the vaccination of antigen-pulsed mature DCs led to increased anti-dsDNA antibody production and an aggravation of lupus-like disease in the model. CONCLUSIONS; These results suggested the high potency of iDC vaccine in preventing lupus-like renal injuries induced by pathogenic autoantibodies.

  13. Prevalence of Serum IgG Antibodies to Cystic Echinococcus Antigen among Patients in an Uzbekistan Emergency Hospital.

    Science.gov (United States)

    Park, Se Jin; Han, Sung Sik; Anvarov, Khikmat; Khajibaev, Abdukhakim; Choi, Min-Ho; Hong, Sung-Tae

    2015-12-01

    Cystic echinococcosis (CE) is one of the most widespread zoonotic helminthiases, which can last an asymptomatic infection for several years. The purpose of this study was to demonstrate serum antibody prevalence of CE among asymptomatic people in Uzbekistan using ELISA. A total of 2,547 serum samples were collected, 66 from confirmed CE patients and 2,481 of patients with other diseases than CE at a hospital in Tashkent, Uzbekistan. The serum samples were screened for CE specific IgG antibodies by ELISA using cystic fluid antigen obtained from sheep. The serum antibody positive rate was 89.4% (59/66) in CE and 3.6% (89/2,481) in other disease patients. The present ELISA recognized 89.4% sensitivity and 96.4% specificity. The ELISA absorbance of positive samples was distributed 0.271-0.971 for CE and 0.273-0.887 for other disease patients. The other disease patients with high absorbance over 0.3 were 50 (2.0%) who were presumed to be active CE patients. The patients in their 40s showed the highest positive rate of 5.2% (P=0.181), and women were 4.4% while men were 3.1% positive (P=0.136). The data confirmed that there are many asymptomatic patients of CE in Tashkent. It is indicated that CE is an endemic disease of public health importance in Uzbekistan.

  14. Environmental quantification of Pasteuria penetrans endospores using in situ antigen extraction and immunodetection with a monoclonal antibody.

    Science.gov (United States)

    Schmidt, L M; Preston, J F; Dickson, D W; Rice, J D; Hewlett, T E

    2003-05-01

    Abstract Pasteuria penetrans is an obligate parasite of root-knot nematodes (Meloidogyne spp.) that has attracted significant attention as a promising biocontrol agent. The inability to culture P. penetrans has invoked the need for a quantitative detection capability to facilitate biocontrol studies. A chemical extraction method using urea, dithiothreitol and CHES buffer (UDC) is shown to release soluble endospore envelope antigen from endospores present in complex matrices, generating an extract that can be used to determine the levels of spores when compared to a standard in an enzyme-linked immunosorbent assay (ELISA) using a specific monoclonal antibody, MAb 2A41D10. Extractions can be performed in less than 1 h. Linear regression analysis routinely produced line fits with r(2)>0.90. Antigen extraction efficiency was not influenced by soil type. Three ELISA formats were analyzed for quantitative detection of P. penetrans endospores. A tertiary ELISA immunodetection system provided the lowest level of detection at approximately 300 spores per gram of soil. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis Western blots of soil extracts containing P. penetrans endospore antigen produced signature peptides bearing a common epitope characteristic of endospores of Pasteuria spp. MAb 2A41D10 was specific for Pasteuria spp. and did not react with extracts of Pasteuria-free soil or with spore extracts of native Gram-positive endospore-forming bacteria. Immunofluorescent microscopy revealed that MAb 2A41D10 recognizes an epitope uniformly distributed on the endospore surface. The development of a rapid extraction method and analysis of solubilized antigen by immunodetection has the potential for broad application in food and environmental microbiology.

  15. The association of heavy and light chain variable domains in antibodies: implications for antigen specificity.

    KAUST Repository

    Chailyan, Anna; Marcatili, Paolo; Tramontano, Anna

    2011-01-01

    of interaction between the heavy and light chain variable domains affects the relative position of the antigen-binding loops and therefore has an effect on the overall conformation of the binding site. In this article, we analyze the structure of the interface

  16. 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).

  17. Generation of Recombinant Monoclonal Antibodies from Immunised Mice and Rabbits via Flow Cytometry and Sorting of Antigen-Specific IgG+ Memory B Cells.

    Directory of Open Access Journals (Sweden)

    Dale O Starkie

    Full Text Available Single B cell screening strategies, which avoid both hybridoma fusion and combinatorial display, have emerged as important technologies for efficiently sampling the natural antibody repertoire of immunized animals and humans. Having access to a range of methods to interrogate different B cell subsets provides an attractive option to ensure large and diverse panels of high quality antibody are produced. The generation of multiple antibodies and having the ability to find rare B cell clones producing IgG with unique and desirable characteristics facilitates the identification of fit-for-purpose molecules that can be developed into therapeutic agents or research reagents. Here, we describe a multi-parameter flow cytometry single-cell sorting technique for the generation of antigen-specific recombinant monoclonal antibodies from single IgG+ memory B cells. Both mouse splenocytes and rabbit PBMC from immunised animals were used as a source of B cells. Reagents staining both B cells and other unwanted cell types enabled efficient identification of class-switched IgG+ memory B cells. Concurrent staining with antigen labelled separately with two spectrally-distinct fluorophores enabled antigen-specific B cells to be identified, i.e. those which bind to both antigen conjugates (double-positive. These cells were then typically sorted at one cell per well using FACS directly into a 96-well plate containing reverse transcriptase reaction mix. Following production of cDNA, PCR was performed to amplify cognate heavy and light chain variable region genes and generate transcriptionally-active PCR (TAP fragments. These linear expression cassettes were then used directly in a mammalian cell transfection to generate recombinant antibody for further testing. We were able to successfully generate antigen-specific recombinant antibodies from both the rabbit and mouse IgG+ memory B cell subset within one week. This included the generation of an anti-TNFR2 blocking

  18. Antigenic Cross-Reactivity Anti-Birtoxin Antibody against Androctonus crassicauda Venom

    Directory of Open Access Journals (Sweden)

    SuhandanAdigüzel Van-Zoelen

    2015-10-01

    Full Text Available Background: Antivenom is still widely used in the treatment of envenomation as there are no vaccines or other effective agents available against animal venoms. Recently, neurotoxins named birtoxin family have been described from Parabuthus transvaalicus and Androctonus crassicauda. The aim of the present study was to test the antibirtoxinantibodies for their ability to neutralize the lethal effects of A. crassicauda scorpion venom.Methods: SDS-PAGE and Western blotting used the presence of components from A. crassicauda and P.transvaalicus scorpion venoms and to determine the degree of cross-reactivity. The Minimum Lethal Dose (MLD of venom was assessed by subcutaneously (sc injections in mice.Results: The MLD of the A. crassicauda venom was 35 μg/ 20g mouse by sc injection route. Western blotting showed the presence of components from A. crassicauda and P. transvaalicus scorpion venoms strongly cross react with the A. crassicauda antivenom. However, Western blotting of the A. crassicauda scorpion venom using the Refik Saydam Public Health Agency (RSPHA generated antibody showed that not all the venom components cross reacted with the anti-birtoxin antibody. The antibodies only cross reacted with components falling under the 19 kDa protein size of A. crassicauda venom.Conclusion: The bioassays and Western blotting of A. crassicauda venom with the anti-birtoxin antibodies produced against a synthetic peptide showed that these antibodies cross reacted but did not neutralize the venom of A. crassicauda.

  19. Characterization of crystals of an antibody-recognition fragment of the cancer differentiation antigen mesothelin in complex with the therapeutic antibody MORAb-009

    International Nuclear Information System (INIS)

    Ma, Jichun; Tang, Wai Kwan; Esser, Lothar; Pastan, Ira; Xia, Di

    2012-01-01

    The therapeutic antibody MORAb-009 disrupts the interaction of mesothelin and the ovarian cancer antigen CA-125. Crystals have been grown of the Fab fragment derived from MORAb-009 and of its complex with an N-terminal fragment of mesothelin. The mesothelin-specific monoclonal antibody MORAb-009 is capable of blocking the binding of mesothelin to CA-125 and displays promising anticancer potential. It is currently undergoing clinical trials. In order to understand the basis of the interaction between MORAb-009 and mesothelin at atomic resolution, both the Fab fragment of MORAb-009 and the complex between the Fab and an N-terminal fragment of mesothelin (residues 7–64) were crystallized. The crystals of the Fab diffracted X-rays to 1.75 Å resolution and had the symmetry of space group P4 1 2 1 2, with unit-cell parameters a = b = 140.6, c = 282.0 Å. The crystals of the mesothelin–Fab complex diffracted to 2.6 Å resolution and belonged to the hexagonal space group P6 4 , with unit-cell parameters a = b = 146.2, c = 80.9 Å. Structural analyses of these molecules are in progress

  20. The relationship of HBsub(s) antigen and antibody to atomic bomb radiation in the adult health study sample, 1975-77

    International Nuclear Information System (INIS)

    Kato, Hiroo; Mayumi, Makoto; Nishioka, Kusuya; Hamilton, H.B.

    1983-01-01

    A study was conducted on the frequency of HBsub(s) positive antigen and antibody reactions as an index for determining whether there is any change in the immune competence as a late observable effect of atomic bomb exposure in Hiroshima and Nagasaki. There was no difference between the two comparison groups in the occurrence of positive HBsub(s) antibody reactions (prevalence of HB virus). However, the frequency of positive HBsub(s) antigen reactions (79% remained persistently antigen-positive) was significantly higher in those exposed to 100 rad or more than in the controls. The same tendency was apparent for the two exposure groups when classified by sex, city, and age, though by age the difference between exposure groups among the younger age groups (age 20 or less at the time of the bomb) was more marked. On the other hand, contrary to expectation, there was no difference between exposure groups in the distribution by high vs low titers among the antigen-positive individuals. There is no difference in the prevalence of positive HBsub(s) antibody reactions between Nagasaki and Hiroshima, but the frequency of positive antigen reactions is higher in Nagasaki. With respect to HBsub(s) antigen subtypes, adr occurs in a higher and adw in a lower frequency in Nagasaki than in Hiroshima, corresponding to earlier reports for the Japan archipelago of reverse and complementary distributions of these two subtypes. (author)

  1. Expression of class 5 antigens by meningococcal strains obtained from patients in Brazil and evaluation of two new monoclonal antibodies

    Directory of Open Access Journals (Sweden)

    Elizabeth N. De Gaspari

    Full Text Available Determining the profile of antigen expression among meningococci is important for epidemiologic surveillance and vaccine development. To this end, two new mouse monoclonal antibodies (MAbs have been derived against Neisseria meningitidis proteins (class 5. The MAbs were reactive against outer membrane antigens and were bactericidal. Selected anti-class 5 MAbs [(5.1-3E6-2; (5.3-3BH4-C7; (5.4-1BG11-C7; (5.5-3DH-F5G9 also 5F1F4-T3(5.c], and the two new monoclonal antibodies C14F10Br2 (5.8 and 7F11B5Br3 (5.9, were then tested against different meningococcal strains, (63 strains of serogroup A, 60 strains of serogroup C (from 1972 to 1974; and 136 strains of serogroup B (from 1992 meningococci. Our results demonstrated that the expression of class 5 proteins in the N. meningitidis B Brazilian strains studied is highly heterogeneous. The serotypes and subtypes of B:4:P1.15, B:4:P1.9, B:4:P1.7, B:4:P1.3, B:4:P1.14, B:4:P1.16, B:4:NT, and B:NT:NT were detected in N. meningitidis B serogroups.The strains C:2a:P1.2 and A:4.21:P1.9 were dominant in the C and A serogroups, respectively. Serogroup B organisms expressed the class 5 epitopes 5.4 (18%, 5.5 (22%, 5.8 (3.6%, 5.9 (8.0% and 5c (38%. Serogroup C expressed class 5 epitopes 5.1 (81%, 5.4 (35%, 5.5 (33% and 5.9 (5.0%; and serogroup A showed reactivity directed at the class 5 protein 5c (47%; and reactivity was present with the new monoclonal antibody, 5.9 (5.5%. We conclude that the two new MAbs are useful in detecting important group B, class 5 antigens, and that a broad selection of serogroup B, class 5 proteins would be required for an effective vaccine based on the class 5 proteins.

  2. Assignment of C1q-binding HLA antibodies as unacceptable HLA antigens avoids positive CDC-crossmatches prior to transplantation of deceased donor organs.

    Science.gov (United States)

    Juhl, David; Marget, Matthias; Hallensleben, Michael; Görg, Siegfried; Ziemann, Malte

    2017-03-01

    Soon, a virtual crossmatch shall replace the complement-dependent cytotoxicity (CDC) allocation crossmatch in the Eurotransplant region. To prevent positive CDC-crossmatches in the recipient centre, careful definition of unacceptable antigens is necessary. For highly sensitized patients, this is difficult by CDC alone. Assignment of all antibodies detected by sensitive assays, however, could prevent organ allocation. To assess the usefulness of the Luminex C1q-assay to prevent positive CDC-crossmatches, all CDC-crossmatches performed prior to deceased kidney transplantation in a 16-month-period were reviewed. Sera causing positive crossmatches were investigated by the C1q-assay. 31 out of 1432 crossmatches (2.2%) were positive. Sera involved in 26 positive crossmatches were available. C1q-binding donor-specific antibodies were detected in 19 sera (73.1%). The other sera were from recipients without any HLA antibodies detectable by CDC or common solid phase assays. Three patients had known Non-HLA antibodies causing positive CDC-results. Four crossmatches were only weak positive. Therefore, avoidance of donors with HLA antigens against whom C1q-binding antibodies were detected would have prevented all positive crossmatches due to HLA antibodies. Provided that all HLA specificities against which antibodies are detected by the Luminex C1q-assay are considered as unacceptable antigens, CDC-crossmatches prior to transplantation might safely be omitted in many patients. They should be maintained in highly immunized patients, however, for whom assignment of all C1q-positive antibodies as unacceptable antigens could lead to a significant delay or even prevention of transplantation. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Antibody response to a T-cell-independent antigen is preserved after splenic artery embolization for trauma.

    Science.gov (United States)

    Olthof, D C; Lammers, A J J; van Leeuwen, E M M; Hoekstra, J B L; ten Berge, I J M; Goslings, J C

    2014-11-01

    Splenic artery embolization (SAE) is increasingly being used as a nonoperative management strategy for patients with blunt splenic injury following trauma. The aim of this study was to assess the splenic function of patients who were embolized. A clinical study was performed, with splenic function assessed by examining the antibody response to polysaccharide antigens (pneumococcal 23-valent polysaccharide vaccine), B-cell subsets, and the presence of Howell-Jolly bodies (HJB). The data were compared to those obtained from splenectomized patients and healthy controls (HC) who had been included in a previously conducted study. A total of 30 patients were studied: 5 who had proximal SAE, 7 who had distal SAE, 8 who had a splenectomy, and 10 HC. The median vaccine-specific antibody response of the SAE patients (fold increase, 3.97) did not differ significantly from that of the HC (5.29; P = 0.90); however, the median response of the splenectomized patients (2.30) did differ (P = 0.003). In 2 of the proximally embolized patients and none of the distally embolized patients, the ratio of the IgG antibody level postvaccination compared to that prevaccination was splenic immune function of embolized patients was preserved, and therefore routine vaccination appears not to be indicated. Although the median antibody responses did not differ between the patients who underwent proximal SAE and those who underwent distal SAE, 2 of the 5 proximally embolized patients had insufficient responses to vaccination, whereas none of the distally embolized patients exhibited an insufficient response. Further research should be done to confirm this finding. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  4. Vascular targeted therapy with anti-prostate-specific membrane antigen monoclonal antibody J591 in advanced solid tumors.

    Science.gov (United States)

    Milowsky, Matthew I; Nanus, David M; Kostakoglu, Lale; Sheehan, Christine E; Vallabhajosula, Shankar; Goldsmith, Stanley J; Ross, Jeffrey S; Bander, Neil H

    2007-02-10

    Based on prostate-specific membrane antigen (PSMA) expression on the vasculature of solid tumors, we performed a phase I trial of antibody J591, targeting the extracellular domain of PSMA, in patients with advanced solid tumor malignancies. This was a proof-of-principle evaluation of PSMA as a potential neovascular target. The primary end points were targeting,toxicity, maximum-tolerated dose, pharmacokinetics (PK), and human antihuman antibody (HAHA) response. Patients had advanced solid tumors previously shown to express PSMA on the neovasculature. They received 111Indium (111ln)-J591 for scintigraphy and PK, followed 2 weeks later by J591 with a reduced amount of 111In for additional PK measurements. J591 dose levels were 5, 10, 20, 40, and 80 mg. The protocol was amended for six weekly administrations of unchelated J591. Patients with a response or stable disease were eligible for re-treatment. Immunohistochemistry assessed PSMA expression in tumor tissues. Twenty-seven patients received monoclonal antibody (mAb) J591. Treatment was well tolerated. Twenty (74%) of 27 patients had at least one area of known metastatic disease targeted by 111In-J591, with positive imaging seen in patients with kidney, bladder, lung, breast, colorectal, and pancreatic cancers, and melanoma. Seven of 10 patient specimens available for immunohistochemical assessment of PSMA expression in tumor-associated vasculature demonstrated PSMA staining. No HAHA response was seen. Three patients of 27 with stable disease received re-treatment. Acceptable toxicity and excellent targeting of known sites of metastases were demonstrated in patients with multiple solid tumor types, highlighting a potential role for the anti-PSMA antibody J591 as a vascular-targeting agent.

  5. Generation and selection of naïve Fab library for parasitic antigen: Anti-BmSXP antibodies for lymphatic filariasis.

    Science.gov (United States)

    Omar, Noorsharmimi; Hamidon, Nurul Hamizah; Yunus, Muhammad Hafiznur; Noordin, Rahmah; Choong, Yee Siew; Lim, Theam Soon

    2018-05-01

    Phage display has been applied successfully as a tool for the generation of monoclonal antibodies (mAbs). Naive antibody libraries are unique as they are able to overcome several limitations associated with conventional mAb generation methods like the hybridoma technology. Here, we performed an in vitro selection and generation of Fab antibodies against Brugia malayi SXP protein (BmSXP), a recombinant antigen for the detection of lymphatic filariasis. We developed a naïve multi ethnic Fab antibody library with an estimated diversity of 2.99 × 10 9 . The antibody library was used to screen for mAbs against BmSXP recombinant antigen. Soluble monoclonal Fab antibodies against BmSXP were successfully isolated from the naïve library. The Fab antibodies obtained were expressed and analyzed to show its binding capability. The diversity obtained from a pool of donors from various ethnic groups allowed for a diverse antibody library to be generated. The mAbs obtained were also functional in soluble form, which makes it useful for further downstream applications. We believe that the Fab mAbs are valuable for further studies and could also contribute to improvements in the diagnosis of filariasis. © 2017 International Union of Biochemistry and Molecular Biology, Inc.

  6. Increased levels of IgA antibodies against CRA and FRA recombinant antigens of Trypanosoma cruzi differentiate digestive forms of Chagas disease.

    Science.gov (United States)

    Vasconcelos, Romero H T; Amaral, Fábio N; Cavalcanti, Maria G A M; Silva, Edimilson D; Ferreira, Antonio G P; Morais, Clarice N L; Gomes, Yara M

    2010-10-01

    In the chronic phase of Chagas disease, individuals infected by Trypanosoma cruzi may be asymptomatic or may present cardiac and/or digestive complications. Our aim here was to analyze the relationship between the presence of specific immunoglobulin A antibodies and the different chronic clinical forms of Chagas disease using two recombinant antigens of Trypanosoma cruzi, cytoplasmatic repetitive antigen and flagellar repetitive antigen. The association of this immunoglobulin isotype with the digestive and cardio-digestive forms of the disease determined by indirect enzyme-linked immunosorbent assay, strongly suggests that IgA antibodies against these recombinant antigens of T. cruzi can be used as an immunological marker of the digestive alterations caused by Chagas disease. The tests performed in this study show that it is possible to differentiate digestive forms of Chagas disease. The knowledge provided by these results may help physicians to manage early alterations in the digestive tract of patients with the indeterminate or cardiac forms of Chagas disease. Prospective studies, however, with follow-up of the patients that presenting with high levels of immunoglobulin A against cytoplasmatic repetitive antigen and flagellar repetitive antigen recombinant antigens, need to be conducted to confirm this hypothesis. 2010 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

  7. Hepatitis B virus surface antigen and antibody markers in children at ...

    African Journals Online (AJOL)

    possible loss of anamnestic response over time, there is the need to consider a birth dose for HBV vaccination for all ... short and long term results as hepatitis B antibody (anti- ... memory may occur resulting in the absence of an anam-.

  8. Comblike dendrimers containing Tn antigen modulate natural killing and induce the production of Tn specific antibodies

    Czech Academy of Sciences Publication Activity Database

    Vepřek, Pavel; Hajdúch, M.; Džubák, P.; Kulík, R.; Poláková, J.; Bezouška, Karel

    2006-01-01

    Roč. 49, č. 21 (2006), s. 6400-6407 ISSN 0022-2623 R&D Projects: GA AV ČR IAA4020213; GA AV ČR IAA5020403; GA ČR GA304/06/1691 Institutional research plan: CEZ:AV0Z40550506; CEZ:AV0Z50200510 Keywords : Tn antigen * glycodendrimer * NKP-P1 Subject RIV: CE - Biochemistry Impact factor: 5.115, year: 2006

  9. Preparasi Imunoglobulin G Kelinci sebagai Antigen Penginduksi Antibodi Spesifik Terhadap Virus Avian Influenza H5N1 Strain Legok

    Directory of Open Access Journals (Sweden)

    Ketut Karuni Nyanakumari Natih

    2010-06-01

    Full Text Available The aim of this research was to prepare rabbit Immunoglobulin G as anti-idiotype antibody (Ab2 ofAvian Influenza Virus (AIV H5N1. A polyclonal antibody was collected from guinea pigs immunized withinactivated AI vaccine H5N1of Legok strain. Antibody of H5N1 AI in serum was detected by Agar gelprecipitation test (AGPT and an Inhibition Hemmaglutination test (IHT. The highest titre of antibodywas obtained one week after the third immunization. Serum of guinea pigs containing IgG was purifiedusing the Montage Antibody purification kit & spin column with Prosep A media (Millipore. The AI H5N1IgG concentration was 8 mg/ml. AI H5N1 IgG, was then digested with pepsin to obtain F(ab2 fraction andwas called Ab1. The concentration of IgG and F(ab2 and purity of IgG were determined by UVspectrophotometer which showed Ab1 concentration 1 mg/ml. Molecular weight was estimated by sodiumdodecyl sulfate- polyacrilamide gel electrophoresis (SDS-PAGE. Ab2 was produced by immunization ofrabbit with Ab1. The first immunization was carried out by subcutaneous injection with 500 ?g of Ab1emulsified in Complete Freund Adjuvant. The immunization was repeated with the same dose of Ab1emulsified in Incomplete Freund Adjuvan at 1 week intervals. One week after the second immunization,rabbit’s serum was harvested and IgG was purified using the Montage Antibody purification kit & spincolumn with Prosep A media (Millipore. The rabbit IgG, called Ab2, was an anti-idiotypic antibody againstAIV-H5N1. In AGPT, a precipitation line appeared between Ab1 and Ab2. A partial reaction appearedbetween Ab2 and the AI H5N1 antigen was also detected. The results indicated that Ab2 is a possiblecandidate of imunogen for protection against an AI virus H5N1 infection.

  10. A serological study of cysticercosis in patients with HIV Estudo sorológico da cisticercose em pacientes com HIV

    Directory of Open Access Journals (Sweden)

    Subhash Chandra Parija

    2009-08-01

    Full Text Available Neurocysticercosis (NCC has attained the importance of one of the most common cause of focal brain lesions in patients infected with HIV (human immunodeficiency virus. Adequate data regarding the rate of this co-infection is lacking. Therefore, the present study was carried out to determine the prevalence of cysticercosis among HIV patients residing in Puducherry or its neighboring districts of Tamil Nadu State, India. A total of one hundred blood samples were collected from HIV seropositive cases visiting JIPMER hospital, Puducherry, between June 2007 and May 2008. Enzyme immunotransfer blot (EITB and enzyme linked immunosorbent assay (ELISA were used to demonstrate anti- T. solium larval stage antibodies and Co-agglutination (Co-A test was used to detect T. solium larval stage antigens in sera. Two HIV seropositive cases were found positive for anti-T. solium larval stage antibody by EITB and four were positive by ELISA. Only one sample was positive by both EITB and ELISA. No serum sample was found positive for T. solium larval stage antigen by Co-A test. The overall seropositivity detected by all the methods was 5% in this study group. The accurate clinical diagnosis of NCC in HIV is difficult due to deranged immunological parameters in the HIV infected patients. The results of this study provides important data on the prevalence of cysticercosis in HIV positive patients in Puducherry and neighboring areas which was previously unknown. This study will also increase awareness among physicians and public health agencies about T. solium cysticercosis in the selected group.Neurocisticercose (NCC tem alcançado a importância de uma das mais comuns causas de lesões focais no cérebro em pacientes infectados pelo HIV (vírus da imunodeficiência adquirida. Dados adequados relativos à frequencia desta co-infecção estão faltando. Portanto, o presente estudo foi realizado para determinar a prevalência da cisticercose entre pacientes com HIV

  11. Production of Monoclonal Antibody Against Excretory-Secretory Antigen of Fasciola hepatica and Evaluation of Its Efficacy in the Diagnosis of Fascioliasis.

    Science.gov (United States)

    Abdolahi Khabisi, Samaneh; Sarkari, Bahador; Moshfe, Abdolali; Jalali, Sedigheh

    2017-02-01

    Parasitological methods are not helpful for the diagnosis of fascioliasis in acute and invasive periods of the disease. Detection of coproantigens seems to be a suitable alternative approach in the diagnosis of fascioliasis. The present study aimed to develop a reliable antigen detection system, using monoclonal antibodies raised against excretory-secretory (ES) antigen of Fasciola hepatica, for the diagnosis of fascioliasis. Fasciola adult worms were collected from the bile ducts of infected animals. Species of the fluke was determined by polymerase chain reaction-restriction fragment length polymorphism (RFLP-PCR). ES antigen of F. hepatica was prepared. For production of monoclonal antibodies, mice were immunized with ES antigens of F. hepatica. Spleen cells from the immunized mice were fused with NS-1 myeloma cells, using polyethylene glycol. Hybridoma cells secreting specific antibody were expanded and cloned by limiting dilution. Moreover, polyclonal antibody was produced against F. hepatica ES antigen in rabbits. A capture enzyme-linked immunosorbent assay (ELISA) system, using produced monoclonal antibody, was designed and stool samples of infected animals along with control samples were tested by the system. The capture ELISA detected the coproantigen in 27 of 30 (90%) parasitologically confirmed fascioliasis cases, while 4 of 39 (10.25%) samples infected with other parasitic infections showed a positive reaction in this system. No positive reactivity was found with healthy control samples. Accordingly, sensitivity of 90% and specificity of 94.2% were obtained for the capture ELISA system. The results were compared with those obtained with commercial BIO-X ELISA, and a very good (kappa = 0.9) agreement was found between the commercial kit and the developed capture ELISA. Findings of this study showed that the produced monoclonal antibody has appropriate performance for the detection of Fasciola coproantigen in stool samples and can be appropriately

  12. Seroprevalence of antibodies against the excreted antigen superoxide dismutase by Trypanosoma cruzi in dogs from the Yucatan Peninsula (Mexico).

    Science.gov (United States)

    López-Cespedes, A; Longoni, S S; Sauri-Arceo, C H; Rodríguez-Vivas, R I; Villegas, N; Escobedo-Ortegón, J; Barrera-Pérez, M A; Sánchez-Moreno, M; Bolio González, M E; Marín, C

    2013-06-01

    Numerous studies have shown the role of dogs as a reservoir for the American trypanosomiasis, as the bridge connecting sylvatic and peridomestic cycles. The objective of this study was to determine the prevalence of American trypanosomiasis in the dog population (630 sera) from seven localities in the Yucatan Peninsula (city of Mérida and the towns of Molas, Playa del Carmen, Akumal, Xcalacoop, Xcalac and Xahuachol). These data are key for developing control measures for the disease. The sera were analysed to detect antibodies against Trypanosoma cruzi, using Fe-SOD excreted as the antigenic fraction by ELISA and Western blot as confirmation. The total prevalence found in the Yucatan Peninsula was some 14.76%, with 10.74% in the state of Yucatan (city of Mérida, towns of Molas and Xcalacoop) and 21.34% in the state of Quintana Roo (towns of Playa del Carmen, Akumal, Xcalac and Xahuachol). However, a more thorough epidemiological study of the dog population, both wild and urban, in the Yucatan Peninsula will be required to design a control strategy for these diseases, paying particular attention to the population affected and even broadening the study to other Mexican states as well as neighbouring countries. These results again confirm that iron-superoxide dismutase excreted by T. cruzi constitutes a good source of antigen for serodiagnosis in epidemiological studies. © 2012 Blackwell Verlag GmbH.

  13. Sequence-Based Discovery Demonstrates That Fixed Light Chain Human Transgenic Rats Produce a Diverse Repertoire of Antigen-Specific Antibodies

    Directory of Open Access Journals (Sweden)

    Katherine E. Harris

    2018-04-01

    Full Text Available We created a novel transgenic rat that expresses human antibodies comprising a diverse repertoire of heavy chains with a single common rearranged kappa light chain (IgKV3-15-JK1. This fixed light chain animal, called OmniFlic, presents a unique system for human therapeutic antibody discovery and a model to study heavy chain repertoire diversity in the context of a constant light chain. The purpose of this study was to analyze heavy chain variable gene usage, clonotype diversity, and to describe the sequence characteristics of antigen-specific monoclonal antibodies (mAbs isolated from immunized OmniFlic animals. Using next-generation sequencing antibody repertoire analysis, we measured heavy chain variable gene usage and the diversity of clonotypes present in the lymph node germinal centers of 75 OmniFlic rats immunized with 9 different protein antigens. Furthermore, we expressed 2,560 unique heavy chain sequences sampled from a diverse set of clonotypes as fixed light chain antibody proteins and measured their binding to antigen by ELISA. Finally, we measured patterns and overall levels of somatic hypermutation in the full B-cell repertoire and in the 2,560 mAbs tested for binding. The results demonstrate that OmniFlic animals produce an abundance of antigen-specific antibodies with heavy chain clonotype diversity that is similar to what has been described with unrestricted light chain use in mammals. In addition, we show that sequence-based discovery is a highly effective and efficient way to identify a large number of diverse monoclonal antibodies to a protein target of interest.

  14. 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.

  15. Taeniasis and cysticercosis prevalence in a small village from Northeastern Brazil Prevalência de teníase e sorologia positiva para cisticercose em Mulungu do Morro, Bahia

    Directory of Open Access Journals (Sweden)

    Irenio Gomes

    2002-06-01

    Full Text Available Although not considered as an endemic region, the Northeast of Brazil has the necessary conditions for the development of taeniasis-cysticercosis complex. In a previous paper, we demonstrated that Mulungu do Morro municipality, in the State of Bahia, has a high seroprevalence to cysticercosis in epileptic patients. OBJECTIVE: to determine the prevalence of taeniasis and positive cysticercosis serology in the population of Mulungu do Morro. METHOD: blood and stool samples were collected from a random sampling of the population, by family. The identification of antibodies against T. solium cysticerci was made by EITB and T. solium antigens were identified using a polyclonal antibody-capture ELISA. RESULTS: the cysticercosis seroprevalence was 1.6% (C.I. = 0.8 to 2.8% and the taeniasis prevalence 4.5% (C.I. = 3.0 to 6.5%. Seropositivity to cysticercosis was higher among those who lived in a house of a person testing positive for coproantigen, p=0.017. CONCLUSION: our results demonstrate that the taeniasis-cysticercosis complex is endemic in Mulungu do Morro. We believe that all areas in the world with the same socio-economic and sanitary characteristics are likely to have high prevalence of this parasite.Embora alguns autores não a considerem uma região endêmica, existem no Nordeste do Brasil as condições necessárias para o desenvolvimento do complexo teníase/ cisticercose. Em uma publicação prévia demosntramos no município de Mulungu do Morro, Bahia, alta soroprevalência para cisticercose em pacientes epilépticos. OBJETIVO: determinar a prevalência de teníase e sorologia positiva para cisticercose na população de Mulungu do Morro. MÉTODO: foram coletadas amostras de sangue e fezes em 175 famílias definidas aleatoriamente. A identificação de anticorpos séricos anti-cisticerco foi feita através do método de EITB e a presença de teníase foi verificada através de ELISA de captura para identificação de antígenos do

  16. Muscular cysticercosis: Case report and imaging findings

    Directory of Open Access Journals (Sweden)

    Neide Regina Simões Olmo

    Full Text Available Summary Cysticercosis is a parasitic disease caused by a worm of the Cestoda class. The most prevalent form affects the nervous system. This case report is from a 78-year-old female patient evaluated at Clínica Mult Imagem, in the city of Santos, Brazil, who presented a form of the disease that differed from the classic neurocysticercosis, in this case muscular cysticercosis. This and other forms of manifestation justify further studies to ensure adequate recognition, diagnosis and treatment of this parasitic disease.

  17. Target antigens for Hs-14 monoclonal antibody and their various expression in normozoospermic and asthenozoospermic men

    Czech Academy of Sciences Publication Activity Database

    Čapková, Jana; Margaryan, Hasmik; Kubátová, Alena; Novák, Petr; Pěknicová, Jana

    2015-01-01

    Roč. 25, č. 11 (2015) ISSN 2051-4190 R&D Projects: GA ČR(CZ) GAP503/12/1834; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:86652036 ; RVO:61388971 Keywords : acrosome * human spermatozoa * monoclonal antibody * asthenozoospermia * transitional endoplasmic reticulum ATPase Subject RIV: CE - Biochemistry http://link.springer.com/article/10.1186/s12610-015-0025-0

  18. Novel Monoclonal Antibodies Recognizing Human Prostate-Specific Membrane Antigen (PSMA) as Research and Theranostic Tools

    Czech Academy of Sciences Publication Activity Database

    Nováková, Zora; Foss, C. A.; Copeland, B. T.; Morath, V.; Baranová, Petra; Havlínová, Barbora; Skerra, A.; Pomper, M.G.; Bařinka, Cyril

    2017-01-01

    Roč. 77, č. 7 (2017), s. 749-764 ISSN 0270-4137 R&D Projects: GA ČR GAP301/12/1513; GA MŠk(CZ) LQ1604; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:86652036 Keywords : monoclonal antibody * glutamate carboxypeptidase II * NAALADase Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition OBOR OECD: Endocrinology and metabolism (including diabetes, hormones) Impact factor: 3.820, year: 2016

  19. 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

  20. 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

  1. How-to-do-it: Immunological Assays for the Classroom 1. Enzyme Linked Immunosorbent Assay (ELISA): A Laboratory Tool for Demonstration of Antibody-Antigen Interaction.

    Science.gov (United States)

    Russo, A. J.; And Others

    1984-01-01

    Background information, list of required materials, and procedures are provided for an immunological assay which has been modified for use as a classroom/laboratory demonstration of antigen-antibody reaction. The assay is designed for a two and one-half hour laboratory period but may be modified for one hour laboratories. (JN)

  2. Comparative analysis of monoclonal antibodies against prostate-specific membrane antigen (PSMA)

    Czech Academy of Sciences Publication Activity Database

    Tykvart, Jan; Navrátil, Václav; Sedlák, František; Corey, E.; Colombatti, M.; Fracasso, G.; Koukolík, F.; Bařinka, Cyril; Šácha, Pavel; Konvalinka, Jan

    2014-01-01

    Roč. 74, č. 16 (2014), s. 1674-1690 ISSN 0270-4137 R&D Projects: GA ČR GAP304/12/0847; GA MŠk LO1302; GA ČR GAP301/12/1513; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:61388963 ; RVO:86652036 Keywords : glutamate carboxypeptidase II * prostate -specific membrane antigen * folate hydrolase * NAALADase * Western blot * immunohistochemistry * ELISA * flow cytometry * surface plasmon resonance Subject RIV: CE - Biochemistry Impact factor: 3.565, year: 2014

  3. Analysis of the specificity of human antibodies to antigens of Leishmania braziliensis braziliensis

    Directory of Open Access Journals (Sweden)

    Aoi Masuda

    1989-08-01

    Full Text Available The antigenicity of promastigotes of Leishmania braziliensis braziliensis (L. b.braziliensis treated with 1% sodium desoxycholate in 10 mM Tris-Hcl pH 8.2 was analysed by immunoblot using as probes sera from American cutaneous leishmaniasis (ACL, American visceral leishmaniasis (AVL, schistosomiasis, malaria and Chagas' disease. The ACL sera reacted constantly with a 60 kD band. No reactivity to this protein was observed with sera from the other diseases above mentioned indicating that the 60 kD protein may be used in serodiagnosis for ACL.

  4. 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)

  5. Antibody to hepatitis B surface antigen among employees in the National Hospital, Oslo, Norway: a prevalence study.

    Science.gov (United States)

    Hovig, B; Rollag, H; Dahl, O

    1985-07-01

    During the last decade, several studies of serologic markers of hepatitis B virus infections in hospital personnel have demonstrated an increased prevalence of antibodies to hepatitis B virus (anti-HB) compared with the general population. Norway has a very low incidence rate of hepatitis B as seen on a global scale, and this study was performed to evaluate the infection risk by hospital workers in such environments. The employees, 2,546 (94.7% of the population), in the 800-bed National Hospital in Oslo were tested for antibody to hepatitis B surface antigen (anti-HBs) in serum. Five per cent (128 persons) were anti-HBs-positive; this was only slightly higher than that in the general Norwegian population. Male employees were more often positive than females (7.0% vs. 4.4%). Staff more than 50 years of age or with 16 or more years of employment in the health services had a rate twice as high as the rest of the employees. Staff in the porter services (mostly men) had a higher rate than others, whereas the rates in the different professional groups showed no statistical differences. Contrary to many other studies, significant differences in prevalence according to frequency of patient contact or blood handling were not found.

  6. Demonstration of monoclonal anti-carcinoembryonic antigen (CEA) antibody internalization by electron microscopy, western blotting and radioimmunoassay.

    Science.gov (United States)

    Tsaltas, G; Ford, C H; Gallant, M

    1992-01-01

    One of the important factors affecting the action of monoclonal antibodies (Mabs) or immunoconjugates on tumour sites depends on whether the Mab is internalized by the cancer cells in question. The underexplored subject of internalization is discussed in this paper, and a number of in vitro techniques for investigating internalization are evaluated, using a model which consists of a well characterized anti-carcinoembryonic antigen (anti-CEA) Mab and a number of CEA expressing human cancer cell lines. Employing two alternative radiolabeling assays, evidence for internalization of the anti-CEA Mab by a CEA-positive colorectal cancer cell line (LS174T) was obtained throughout the time intervals examined (5 min to 150 min). Electronmicroscopy employing horseradish-peroxidase labeled anti-CEA Mab and control antibody permitted direct visualization of anti-CEA Mab-related staining in intracellular compartments of a high CEA-expressor human colorectal cell line (SKCO1). Finally Western blots of samples derived from cytosolic and membrane components of solubilized cells from lung and colonic cancer cell lines provided evidence for internalized anti-CEA Mab throughout seven half hour intervals, starting at 5 minutes. Internalized anti-CEA was detected in all CEA expressing cell lines (LS174T, SKCO1, BENN) but not in the case of a very low CEA expressor line (COLO 320).

  7. Hemolytic disease of the fetus and newborn caused by an antibody to a low-prevalence antigen, anti-SARA.

    Science.gov (United States)

    Towns, Dale; Hannon, Judith; Hendry, Julia; Barnes, Janet; Goldman, Mindy

    2011-09-01

    The first case describing the SARAH (SARA) antigen occurred in 1990, in an Australian blood donor. Hemolytic disease of the fetus and newborn (HDFN) due to anti-SARA has not been previously described. We report a case of HDFN in a multiparous female. The pregnancy was unremarkable except that she was involved in a seemingly minor motor vehicle accident at 25 weeks' gestation. Routine prenatal antibody screening was negative throughout the pregnancy. She presented at 37 weeks' gestation because of decreased fetal movements. Labor was induced and a 2702-g infant male was delivered. The infant's hemoglobin was 49 g/L and the bilirubin was 153 µmol/L. Blood samples from the parents and infant were referred to Canadian Blood Services National Immunohematology Reference Laboratory and subsequently to the Australian Red Cross Red Cell Reference Service. The father's and infant's red blood cells were confirmed to be SARA positive, and the mother's plasma contained anti-SARA. The infant was successfully treated with a double-volume exchange transfusion. This is the first example of HDFN associated with this antibody. © 2011 American Association of Blood Banks.

  8. Radioimmunodetection of metastases of colorectal carcinoma by external scintigraphy after administration of 131I-antibody to carcinoembryonic antigen

    International Nuclear Information System (INIS)

    Jones, B.E.; Begent, R.H.J.; Jewkes, R.F.; Vernon, P.; Searle, F.; Keep, P.A.; Green, A.J.; Bagshawe, K.D.

    1982-01-01

    Patients suspected of having metastases of colorectal carcinoma but without palpable tumour deposits were given an intravenous injection of affinity purified goat antibody to carcinoembryonic antigen (CEA) which had been labelled with 131 I by the chloramine T method. 24 Hours later images of antibody distribution were obtained with a large field gamma camera. Computer substraction of background radioactivity was performed using the image obtained after injection of sup(99m)Technetium labelled albumen and free sup(99m)TcO 4 . 23 Scans were carried out in 16 patients and 22 scan images showed residual uptake in specific areas which were considered positive for tumour. Evidence of metastasis was found at these sites in 10 patients, at surgery in 6, by computerised tomography in 3 and by ultrasound in 1. Probable false positive results were obtained in 3 scans. Metastases are still suspected in 4 patients although localisation has not been confirmed. Radioimmunodetection appears to have potential as a method for detecting metastases of colorectal carcinoma. (Author)

  9. Liver cytosolic 1 antigen-antibody system in type 2 autoimmune hepatitis and hepatitis C virus infection.

    Science.gov (United States)

    Lenzi, M; Manotti, P; Muratori, L; Cataleta, M; Ballardini, G; Cassani, F; Bianchi, F B

    1995-01-01

    Within the multiform liver/kidney microsomal (LKM) family, a subgroup of sera that reacts with a liver cytosolic (LC) protein has been isolated and the new antigen-antibody system is called LC1. Unlike LKM antibody type 1 (anti-LKM1), anti-LC1 is said to be unrelated to hepatitis C virus (HCV) infection and has therefore been proposed as a marker of 'true' autoimmune hepatitis type 2. Altogether 100 LKM1 positive sera were tested by immunodiffusion (ID). Twenty five gave a precipitation line with human liver cytosol; 17 of the 25 also reacted with rat liver cytosol. Thirteen of the 25 sera were anti-HCV positive by second generation ELISA: anti-HCV positive patients were significantly older (p LKM1, and that it is an additional marker of juvenile autoimmune hepatitis type 2. It does not, however, discriminate between patients with and without HCV infection. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 PMID:7797126

  10. Inhibition of Spontaneous Breast Cancer Metastasis by Anti—Thomsen-Friedenreich Antigen Monoclonal Antibody JAA-F11

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    Jamie Heimburg

    2006-11-01

    Full Text Available Thomsen-Friedenreich antigen (TF-Ag is expressed in many carcinomas, including those of the breast, colon, bladder, prostate. TF-Ag is important in adhesion and metastasis and as a potential immunotherapy target. We hypothesized that passive transfer of JAAF11, an anti -TF-Ag monoclonal antibody, may create a survival advantage for patients with TIF-Ag -expressing tumors by cytotoxicity, blocking of tumor cell adhesion, inhibition of metastasis. This was tested using in vitro models of tumor cell growth; cytotoxicity assays; in vitro, ex vivo, in vivo models of cancer metastasis; and, finally, in vivo effects in mice with metastatic breast cancer. Unlike some anti-TF-Ag antibodies, JAA-F11 did not enhance breast carcinoma cell growth. JAA-F11 did not induce the killing of 4T1 tumor cells through complement-dependent cytotoxicity or apoptotic mechanisms. However, JAA-F11 blocked the stages of metastasis that involve the adhesion of human breast carcinoma cells to human endothelial cells (human umbilical vein endothelial cells and human bone marrow endothelial cells 60 in in vitro static adhesion models, in a perfused ex vivo model, in murine lung vasculature in an in vivo metastatic deposit formation assay. JAA-F11 significantly extended the median survival time of animals bearing metastatic 4T1 breast tumors and caused a > 50% inhibition of lung metastasis.

  11. 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

  12. Novel Non-Histocompatibility Antigen Mismatched Variants Improve the Ability to Predict Antibody-Mediated Rejection Risk in Kidney Transplant

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    Silvia Pineda

    2017-12-01

    Full Text Available Transplant rejection is the critical clinical end-point limiting indefinite survival after histocompatibility antigen (HLA mismatched organ transplantation. The predominant cause of late graft loss is antibody-mediated rejection (AMR, a process whereby injury to the organ is caused by donor-specific antibodies, which bind to HLA and non-HLA (nHLA antigens. AMR is incompletely diagnosed as donor/recipient (D/R matching is only limited to the HLA locus and critical nHLA immunogenic antigens remain to be identified. We have developed an integrative computational approach leveraging D/R exome sequencing and gene expression to predict clinical post-transplant outcome. We performed a rigorous statistical analysis of 28 highly annotated D/R kidney transplant pairs with biopsy-confirmed clinical outcomes of rejection [either AMR or T-cell-mediated rejection (CMR] and no-rejection (NoRej, identifying a significantly higher number of mismatched nHLA variants in AMR (ANOVA—p-value = 0.02. Using Fisher’s exact test, we identified 123 variants associated mainly with risk of AMR (p-value < 0.001. In addition, we applied a machine-learning technique to circumvent the issue of statistical power and we found a subset of 65 variants using random forest, that are predictive of post-tx AMR showing a very low error rate. These variants are functionally relevant to the rejection process in the kidney and AMR as they relate to genes and/or expression quantitative trait loci (eQTLs that are enriched in genes expressed in kidney and vascular endothelium and underlie the immunobiology of graft rejection. In addition to current D/R HLA mismatch evaluation, additional mismatch nHLA D/R variants will enhance the stratification of post-tx AMR risk even before engraftment of the organ. This innovative study design is applicable in all solid organ transplants, where the impact of mitigating AMR on graft survival may be greater, with considerable benefits on

  13. Using molecular principal axes for structural comparison: determining the tertiary changes of a FAB antibody domain induced by antigenic binding

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    Silverman B David

    2007-11-01

    Full Text Available Abstract Background Comparison of different protein x-ray structures has previously been made in a number of different ways; for example, by visual examination, by differences in the locations of secondary structures, by explicit superposition of structural elements, e.g. α-carbon atom locations, or by procedures that utilize a common symmetry element or geometrical feature of the structures to be compared. Results A new approach is applied to determine the structural changes that an antibody protein domain experiences upon its interaction with an antigenic target. These changes are determined with the use of two different, however comparable, sets of principal axes that are obtained by diagonalizing the second-order tensors that yield the moments-of-geometry as well as an ellipsoidal characterization of domain shape, prior to and after interaction. Determination of these sets of axes for structural comparison requires no internal symmetry features of the domains, depending solely upon their representation in three-dimensional space. This representation may involve atomic, Cα, or residue centroid coordinates. The present analysis utilizes residue centroids. When the structural changes are minimal, the principal axes of the domains, prior to and after interaction, are essentially comparable and consequently may be used for structural comparison. When the differences of the axes cannot be neglected, but are nevertheless slight, a smaller relatively invariant substructure of the domains may be utilized for comparison. The procedure yields two distance metrics for structural comparison. First, the displacements of the residue centroids due to antigenic binding, referenced to the ellipsoidal principal axes, are noted. Second, changes in the ellipsoidal distances with respect to the non-interacting structure provide a direct measure of the spatial displacements of the residue centroids, towards either the interior or exterior of the domain

  14. Purification and refolding of anti-T-antigen single chain antibodies (scFvs) expressed in Escherichia coli as inclusion bodies.

    Science.gov (United States)

    Yuasa, Noriyuki; Koyama, Tsubasa; Fujita-Yamaguchi, Yoko

    2014-02-01

    T-antigen (Galβ1-3GalNAcα-1-Ser/Thr) is an oncofetal antigen that is commonly expressed as a carbohydrate determinant in many adenocarcinomas. Since it is associated with tumor progression and metastasis, production of recombinant antibodies specific for T-antigen could lead to the development of cancer diagnostics and therapeutics. Previously, we isolated and characterized 11 anti-T-antigen phage clones from a phage library displaying human single-chain antibodies (scFvs) and purified one scFv protein, 1G11. More recently, we purified and characterized 1E8 scFv protein using a Drosophila S2 expression system. In the current study, four anti-T-antigen scFv genes belonging to Groups 1-4 were purified from inclusion bodies expressed in Escherichia coli cells. Inclusion bodies isolated from E. coli cells were denatured in 3.5 M Gdn-HCl. Solubilized His-tagged scFv proteins were purified using Ni(2+)-Sepharose column chromatography in the presence of 3.5 M Gdn-HCl. Purified scFv proteins were refolded according to a previously published method of step-wise dialysis. Two anti-T-antigen scFv proteins, 1E6 and 1E8 that belong to Groups 1 and 2, respectively, were produced in sufficient amounts, thus allowing further characterization of their binding activity with T-antigen. Specificity and affinity constants determined using enzyme-linked immunosorbent assay (ELISA) and surface plasmon resonance (SPR), respectively, provided evidence that both 1E8 and 1E6 scFv proteins are T-antigen specific and suggested that 1E8 scFv protein has a higher affinity for T-antigen than 1E6 scFv protein.

  15. Antibody formation in pregnant women with maternal-neonatal human platelet antigen mismatch from a hospital in northern Taiwan

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    Wan-Hua Yang

    2014-01-01

    Full Text Available Neonatal alloimmune thrombocytopenia (NAIT is a clinical syndrome that resembles hemolytic disease of the newborn, affecting the platelets only. The thrombocytopenia results from the maternal alloantibodies reacting with specific human platelet antigens (HPAs on the fetal platelets. Forty-four maternal plasma samples were screened for platelet alloantibodies using qualitative solid phase enzyme-linked immunosorbent assay (ELISA commercial kit (LIFECODES Pakplus, Hologic Gen-Probe GTI Diagnostics, Waukesha, WI, USA, and both the maternal and the corresponding cord blood samples were genotyped (LIFECODES ThromboType, Hologic Gen-Probe GTI Diagnostics, Waukesha, WI, USA. HPA genotyping results correlated with the genetic frequencies in the Taiwan population. A total of 34 newborns (77.3% had partial HPA genotyping mismatches with the corresponding mothers. The most common partial mismatches between mothers and neonates in HPA genotypes were 13 (29.5% in both HPA-3b and HPA-15a, followed by 12 (27.3% in HPA-15b, and 8 (18.2% in HPA-3a. The frequencies of homozygotic mother with heterozygotic neonate were 15.9% in both HPA-3a and HPA-15b, 9.1% in HPA-15a, 6.8% in HPA-3b, and 2.3% in both HPA-2a and HPA-6a. In this study, maternal HPA antibodies were found in five samples, whereas HLA class I antibodies were found in seven maternal plasma samples from the antibody screen. The results from this study have demonstrated that HPA mismatch is not the main cause for the production of HPA alloantibodies.

  16. Therapeutically targeting glypican-2 via single-domain antibody-based chimeric antigen receptors and immunotoxins in neuroblastoma.

    Science.gov (United States)

    Li, Nan; Fu, Haiying; Hewitt, Stephen M; Dimitrov, Dimiter S; Ho, Mitchell

    2017-08-08

    Neuroblastoma is a childhood cancer that is fatal in almost half of patients despite intense multimodality treatment. This cancer is derived from neuroendocrine tissue located in the sympathetic nervous system. Glypican-2 (GPC2) is a cell surface heparan sulfate proteoglycan that is important for neuronal cell adhesion and neurite outgrowth. In this study, we find that GPC2 protein is highly expressed in about half of neuroblastoma cases and that high GPC2 expression correlates with poor overall survival compared with patients with low GPC2 expression. We demonstrate that silencing of GPC2 by CRISPR-Cas9 or siRNA results in the inhibition of neuroblastoma tumor cell growth. GPC2 silencing inactivates Wnt/β-catenin signaling and reduces the expression of the target gene N-Myc, an oncogenic driver of neuroblastoma tumorigenesis. We have isolated human single-domain antibodies specific for GPC2 by phage display technology and found that the single-domain antibodies can inhibit active β-catenin signaling by disrupting the interaction of GPC2 and Wnt3a. To explore GPC2 as a potential target in neuroblastoma, we have developed two forms of antibody therapeutics, immunotoxins and chimeric antigen receptor (CAR) T cells. Immunotoxin treatment was demonstrated to inhibit neuroblastoma growth in mice. CAR T cells targeting GPC2 eliminated tumors in a disseminated neuroblastoma mouse model where tumor metastasis had spread to multiple clinically relevant sites, including spine, skull, legs, and pelvis. This study suggests GPC2 as a promising therapeutic target in neuroblastoma.

  17. Commercial bacterins did not induce detectable levels of antibodies in mice against Mycoplasma hyopneumoniae antigens strongly recognized by swine immune system

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    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.

  18. Assessment of specific IgM antibodies to core antigen of hepatitis B virus in acute and chronic hepatitis B using immunoradiometric assay

    Energy Technology Data Exchange (ETDEWEB)

    Zichova, M; Vodak, M; Kostrhun, L; Nadvornik, V; Stransky, J

    1987-12-31

    A group of 24 patients with acute viral hepatitis B was assessed for specific antibodies against the ''core'' antigen class IgM (HB/sub c/AB IgM) during 1st-4th week of the illness. These specific antibodies were positive in all patients, the mean titre being 10/sup -5/. The high content of these antibodies persisted for 1-2 months after the onset of the disease. The assessment of specific antibodies against ''core'' antigen class IgM was also made in a group of 39 patients with chronic hepatitis. In these patients positive HB/sub c/Ab IgM with a lower content were found (titre 10/sup -3/) than in the group with acute viral hepatitis B. Based on the results the conclusion is made that specific antibodies HB/sub c/Ab class IgM are, in addition to the estimation of the surface antigen of the hepatitis B virus (HB/sub s/Ag), one more indicator of acute viral hepatitis B. The assessment is diagnostically valuable, in particular in acute hepatitis of obscure etiology, in acute jaundice of obscure etiology for the period of low and short-term antigenemia. (author). 6 figs., 1 tab., 14 refs.

  19. Assessment of specific IgM antibodies to core antigen of hepatitis B virus in acute and chronic hepatitis B using immunoradiometric assay

    International Nuclear Information System (INIS)

    Zichova, M.; Vodak, M.; Kostrhun, L.; Nadvornik, V.; Stransky, J.

    1986-01-01

    A group of 24 patients with acute viral hepatitis B was assessed for specific antibodies against the ''core'' antigen class IgM (HB c AB IgM) during 1st-4th week of the illness. These specific antibodies were positive in all patients, the mean titre being 10 -5 . The high content of these antibodies persisted for 1-2 months after the onset of the disease. The assessment of specific antibodies against ''core'' antigen class IgM was also made in a group of 39 patients with chronic hepatitis. In these patients positive HB c Ab IgM with a lower content were found (titre 10 -3 ) than in the group with acute viral hepatitis B. Based on the results the conclusion is made that specific antibodies HB c Ab class IgM are, in addition to the estimation of the surface antigen of the hepatitis B virus (HB s Ag), one more indicator of acute viral hepatitis B. The assessment is diagnostically valuable, in particular in acute hepatitis of obscure etiology, in acute jaundice of obscure etiology for the period of low and short-term antigenemia. (author). 6 figs., 1 tab., 14 refs

  20. Prevalence of Taenia solium cysticercosis in swine from a community-based study in 21 villages of the Eastern Cape Province, South Africa.

    Science.gov (United States)

    Krecek, R C; Michael, L M; Schantz, P M; Ntanjana, L; Smith, M F; Dorny, P; Harrison, L J S; Grimm, F; Praet, N; Willingham, A L

    2008-06-14

    The pork tapeworm, Taenia solium, causative organism of porcine cysticercosis and human neurocysticercosis is known to occur in areas of South Africa including Eastern Cape Province but, despite increasing reports of its occurrence throughout the subregion, the prevalence is yet to be clearly established. The parasite presents a potentially serious agricultural problem and public health risk in endemic areas. The human populations considered to be at highest risk of infection with this zoonotic helminth are people living in rural areas most of whom earn their livelihood wholly or partially through livestock rearing. Here we report on initial results of a community-based study of pigs owned by resource-poor, emerging pig producers from 21 villages in the Eastern Cape Province. Lingual examination (tongue palpation) in live pigs, two enzyme-linked immunosorbent assays (ELISAs), which detect parasite antigen (B158/B60 Ag-ELISA and HP10 Ag-ELISA) and an enzyme immunotransfer blot (EITB) assay, which detects antiparasite antibody, were used to verify endemicity and estimate apparent prevalence. In the absence of a gold standard true prevalence was obtained, using a Bayesian approach, with a model that uses both available data and prior information. Results indicate that the parasite is indeed present in the study villages and that true prevalence was 64.6%. The apparent prevalences as measured by each of the four tests were: 11.9% for lingual examination, 54.8% for B158/B60 Ag-ELISA, 40.6% for HP10 Ag-ELISA and 33.3% for EITB. This base-line knowledge of the prevalence of T. solium in pigs provides information essential to the design and monitoring of sustainable and appropriate interventions for cysticercosis prevention and control.

  1. Recombinant major outer membrane protein (MOMP) of Chlamydophila abortus, Chlamydophila pecorum, and Chlamydia suis as antigens to distinguish chlamydial species-specific antibodies in animal sera.

    Science.gov (United States)

    Hoelzle, Ludwig E; Hoelzle, Katharina; Wittenbrink, Max M

    2004-10-05

    Recombinant major outer membrane proteins (rMOMP) of Chlamydophila (Ch.) abortus, Ch. pecorum, and Chlamydia (C.) suis were used as antigens to distinguish chlamydial species-specific antibodies in (i) immune sera from six rabbits and three pigs raised against native purified elementary bodies, (ii) serum samples from 25 sows vaccinated with Ch. abortus, and (iii) 40 serum samples from four heifers experimentally infected with Ch. abortus. All post-exposition sera contained chlamydial antibodies as confirmed by strong ELISA seroreactivities against the chlamydial LPS. For the rMOMP ELISA mean IgG antibody levels were at least 5.8-fold higher with the particular rMOMP homologous to the chlamydial species used for immunisation or infection than with heterologous rMOMPs (P <0.001). Preferential rMOMP ELISA reactivities of sera were confirmed by Western blotting. The results suggest that the entire chlamydial rMOMP could provide a species-specific serodiagnostic antigen.

  2. Arthrogenicity of type II collagen monoclonal antibodies associated with complement activation and antigen affinity.

    Science.gov (United States)

    Koobkokkruad, Thongchai; Kadotani, Tatsuya; Hutamekalin, Pilaiwanwadee; Mizutani, Nobuaki; Yoshino, Shin

    2011-11-04

    The collagen antibody-induced arthritis (CAIA) model, which employs a cocktail of monoclonal antibodies (mAbs) to type II collagen (CII), has been widely used for studying the pathogenesis of autoimmune arthritis. In this model, not all mAbs to CII are capable of inducing arthritis because one of the initial events is the formation of collagen-antibody immune complexes on the cartilage surface or in the synovium, and subsequent activation of the complement by the complexes induces arthritis, suggesting that a combination of mAbs showing strong ability to bind mouse CII and activate the complement may effectively induce arthritis in mice. In the present study, we examined the relationship between the induction of arthritis by the combination of IgG2a (CII-6 and C2A-12), IgG2b (CII-3, C2B-14 and C2B-16) and IgM (CM-5) subclones of monoclonal antibodies (mAb) of anti-bovine or chicken CII and the ability of mAbs to activate complement and bind mouse CII. DBA/1J mice were injected with several combinations of mAbs followed by lipopolysaccharide. Furthermore, the ability of mAbs to activate the complement and bind mouse CII was examined by ELISA. First, DBA/1J mice were injected with the combined 4 mAbs (CII-3, CII-6, C2B-14, and CM-5) followed by lipopolysaccharide, resulting in moderate arthritis. Excluding one of the mAbs, i.e., using only CII-3, CII-6, and C2B-14, induced greater inflammation of the joints. Next, adding C2A-12 but not C2B-16 to these 3 mAbs produced more severe arthritis. A combination of five clones, consisting of all 5 mAbs, was less effective. Histologically, mice given the newly developed 4-clone cocktail had marked proliferation of synovial tissues, massive infiltration by inflammatory cells, and severe destruction of cartilage and bone. Furthermore, 4 of the 6 clones (CII-3, CII-6, C2B-14, and C2A-12) showed not only a strong cross-reaction with mouse CII but also marked activation of the complement in vitro. The combination of 4 mAbs showing

  3. Arthrogenicity of type II collagen monoclonal antibodies associated with complement activation and antigen affinity

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    Mizutani Nobuaki

    2011-11-01

    Full Text Available Abstract Background The collagen antibody-induced arthritis (CAIA model, which employs a cocktail of monoclonal antibodies (mAbs to type II collagen (CII, has been widely used for studying the pathogenesis of autoimmune arthritis. In this model, not all mAbs to CII are capable of inducing arthritis because one of the initial events is the formation of collagen-antibody immune complexes on the cartilage surface or in the synovium, and subsequent activation of the complement by the complexes induces arthritis, suggesting that a combination of mAbs showing strong ability to bind mouse CII and activate the complement may effectively induce arthritis in mice. In the present study, we examined the relationship between the induction of arthritis by the combination of IgG2a (CII-6 and C2A-12, IgG2b (CII-3, C2B-14 and C2B-16 and IgM (CM-5 subclones of monoclonal antibodies (mAb of anti-bovine or chicken CII and the ability of mAbs to activate complement and bind mouse CII. Methods DBA/1J mice were injected with several combinations of mAbs followed by lipopolysaccharide. Furthermore, the ability of mAbs to activate the complement and bind mouse CII was examined by ELISA. Results First, DBA/1J mice were injected with the combined 4 mAbs (CII-3, CII-6, C2B-14, and CM-5 followed by lipopolysaccharide, resulting in moderate arthritis. Excluding one of the mAbs, i.e., using only CII-3, CII-6, and C2B-14, induced greater inflammation of the joints. Next, adding C2A-12 but not C2B-16 to these 3 mAbs produced more severe arthritis. A combination of five clones, consisting of all 5 mAbs, was less effective. Histologically, mice given the newly developed 4-clone cocktail had marked proliferation of synovial tissues, massive infiltration by inflammatory cells, and severe destruction of cartilage and bone. Furthermore, 4 of the 6 clones (CII-3, CII-6, C2B-14, and C2A-12 showed not only a strong cross-reaction with mouse CII but also marked activation of the

  4. 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

  5. Estudo da cisticercose em pacientes portadores de epilepsia residentes em municípios do Cariri paraibano Cysticercosis research in epileptic patients dwelling in towns of the western Cariri in the State of Paraíba, Brazil

    Directory of Open Access Journals (Sweden)

    Francisca Inês de Sousa Freitas

    2005-09-01

    Full Text Available Este estudo contou com uma amostra de 110 pacientes epilépticos residentes no Cariri paraibano, tendo sido desenvolvido em três etapas sucessivas. Durante a primeira etapa, aplicou-se a ficha epidemiológica visando identificar fatores de risco associados ao complexo teníase-cisticercose na etiologia da epilepsia dos pacientes. A segunda etapa consistiu em exames imunológicos dos 110 pacientes com a utilização da técnica EITB para a identificação de anticorpos séricos anti-cisticercos, e da técnica ELISA para a presença de antígenos circulantes. Na terceira etapa, treze pacientes com sorologia considerada positiva foram submetidos a exames tomográficos. A partir da aplicação do questionário, foram detectados alguns fatores de risco. A soroprevalência constatada foi 118,2/1000 habitantes. Dos 13 pacientes com sorologia positiva para cisticercose, 46,1% têm lesões sugestivas de cisticercose de localização parenquimatosa. Conclui-se que os municípios estudados apresentam perfil epidemiológico compatível com a ocorrência do complexo teníase-cisticercose e que a cisticercose possivelmente desempenhe papel importante no surgimento da epilepsia nesses pacientes.This research involved a sample of 110 epileptic patients from western Cariri, Paraíba, Brazil and it has been developed in three successive phases. During the first one, an epidemiological form was applied with the aim of identifying risk factors related to the taeniasis cysticercosis complex in the etiology of the patients' epilepsy. The second phase consisted of immunological exams of 110 patients, by means of the EITB technique to identify the anti-cysticerci serum antibodies, whereas the presence of circulating antigens was verified through the ELISA technique. In the third phase, thirteen patients who were seropositive, were submitted to brain CT scan. Applying the questionnaire enabled us to know some risk factors. The seroprevalence detected was 118

  6. Immunoglobulin variable region sequences of two human monoclonal antibodies directed to an onco-developmental carbohydrate antigen, lactotetraosylceramide (LcOse4Cer).

    Science.gov (United States)

    Yago, K; Zenita, K; Ohwaki, I; Harada, R; Nozawa, S; Tsukazaki, K; Iwamori, M; Endo, N; Yasuda, N; Okuma, M

    1993-11-01

    A human monoclonal antibody, 11-50, was generated and was shown to recognize an onco-developmental carbohydrate antigen, LcOse4Cer. The isotype of this antibody was IgM, lambda, similar to the previously known human anti-LcOse4 antibodies, such as IgMWOO and HMST-1. We raised a murine anti-idiotypic antibody G3 (IgG1, kappa) against 11-50, and tested its reactivity towards the affinity purified human polyclonal anti-LcOse4 antibodies prepared from pooled human sera using a Gal beta 1-->3GlcNAc beta-immobilized column. The results indicated that at least a part of the human polyclonal anti-LcOse4 antibodies shared the G3 idiotype with 11-50. We further analyzed the sequence of variable regions of the two anti-LcOse4 antibodies, 11-50 and HMST-1. Sequence analysis of the heavy chain variable regions indicated that the VH regions of these two antibodies were highly homologous to each other (93.5% at the nucleic acid level), and these antibodies utilized the germline genes VH1.9III and hv3005f3 as the VH segments, which are closely related germline genes of the VHIII family. It was noted that these germline VH genes are frequently utilized in fetal B cells. The JH region of both antibodies was encoded by the JH4 gene. For the light chain, the V lambda segments of the two antibodies were 96.3% homologous to each other at the nucleic acid level. The V lambda segments of both antibodies showed the highest homology to the rearranged V lambda gene called V lambda II.DS among reported V lambda genes, while the exact germline V lambda genes encoding the two antibodies were not yet registered in available sequence databanks. The amino acid sequences of the J lambda segments of both antibodies were identical. These results indicate that the two human antibodies recognizing the onco-developmental carbohydrate antigen Lc4 are encoded by the same or very homologous germline genes.

  7. diagnosis of bovine cysticercosis in Kenyan cattle

    African Journals Online (AJOL)

    A total of 55 cattle divided into two groups of experimentally (n =30) and naturally ... sensitive than meat inspection in the diagnosis of bovine cysticercosis, detecting .... The second group of 15 calves was ... ined for the presence of C. bovis. .... variable and pour ' ..... appropriate intermediate host is dependent on:- the state.

  8. Seroprevalence of fascioliasis, toxocariasis, strongyloidiasis and cysticercosis in blood samples diagnosed in Medic Medical Center Laboratory, Ho Chi Minh City, Vietnam in 2012.

    Science.gov (United States)

    Nguyen, Toan; Cheong, Fei Wen; Liew, Jonathan Wee Kent; Lau, Yee Ling

    2016-09-05

    Despite the global effort against neglected tropical diseases (NTDs), developing countries with middle to low income are still burdened by them. Vietnam has been undergoing substantial economic growth and urbanization, but underprivileged people living in rural and suburban areas are still having little access to public health infrastructure and proper sanitation. Hitherto, limited information is available for seroprevalence and risk factors of several parasitic diseases in Vietnam. A retrospective study was performed on diagnostic results of Fasciola spp., Toxocara spp., Strongyloides stercoralis and Taenia solium IgG ELISA tests from Medic Medical Center Laboratory, Ho Chi Minh City in 2012. The data were first stratified before statistical analyses were performed. Seroprevalence of fascioliasis, toxocariasis, strongyloidiasis and cysticercosis was determined and the age and gender risk factors were evaluated. Seroprevalence of fascioliasis, toxocariasis, strongyloidiasis and cysticercosis was 5.9 % (590/10,084; 95 % CI: 5.44-6.36), 45.2 % (34,995/77,356; 95 % CI: 44.85-45.55), 7.4 % (3,174/42,920; 95 % CI: 7.15-7.65) and 4.9 % (713/14,601; 95 % CI: 4.55-5.25), respectively. Co-exposure to multiple parasites was detected in 890 males (45.7 %; 95 % CI: 43.49-47.91) and 1,059 females (54.3 %; 95 % CI: 52.09-56.51). Social structure and differences in behavioural factors caused the gender factor to have a significant effect on the prevalence of all the diseases, while the seropositivity for fascioliasis and strongyloidiasis were age group-related. The seroprevalence of fascioliasis, toxocariasis, strongyloidiasis and cysticercosis in the blood samples diagnosed in Medic Medical Center Laboratory, Ho Chi Minh City, in year 2012 were comparatively high. The Vietnamese customs and cultures, dietary habits and agricultural practices exposed them to high risk of contracting NTDs. Despite the possibility of false positive results due to antigenic cross

  9. Autoimmune hepatitis-specific antibodies against soluble liver antigen and liver cytosol type 1 in patients with chronic viral hepatitis.

    Science.gov (United States)

    Rigopoulou, Eirini I; Mytilinaiou, Maria; Romanidou, Ourania; Liaskos, Christos; Dalekos, George N

    2007-02-04

    Non-organ specific autoantibodies are highly prevalent in patients with chronic hepatitis C (HCV). Among them, anti-liver kidney microsomal type 1 (LKM1) antibody--the serological marker of type 2 autoimmune hepatitis (AIH-2)--is detected in up to 11% of the HCV-infected subjects. On the other hand, anti-liver cytosol type 1 antibodies (anti-LC1)--either in association with anti-LKM1, or in isolation--and anti-soluble liver antigen antibodies (anti-SLA) have been considered as useful and specific diagnostic markers for AIH. However, their specificity for AIH has been questioned by some recent studies, which have shown the detection of anti-LC1 and anti-SLA by immunoprecipitation assays in HCV patients irrespective of their anti-LKM1 status. The aim of the present study was to test the anti-LC1 and anti-SLA presence by specific enzyme linked immunosorbent assays (ELISAs), in a large group of Greek HCV-infected patients with or without anti-LKM1 reactivity as firstly, immunoprecipitation assays are limited to few specialized laboratories worldwide and cannot be used routinely and secondly, to assess whether application of such tests has any relevance in the context of patients with viral hepatitis since antibody detection based on such ELISAs has not been described in detail in large groups of HCV patients. One hundred and thirty eight consecutive HCV patients (120 anti-LKM1 negative and 18 anti-LKM1 positive) were investigated for the presence of anti-LC1 and anti-SLA by commercial ELISAs. A similar number (120) of chronic hepatitis B virus (HBV) infected patients seronegative for anti-LKM1 was also tested as pathological controls. Six out of 18 (33%) anti-LKM(pos)/HCV(pos) patients tested positive for anti-LC1 compared to 1/120 (0.83%) anti-LKM(neg)/HCV(pos) patients and 0/120 (0%) of the anti-LKM1(neg)/HBV(pos) patients (p LKM1) or HBV-infected patients. We showed that anti-LC1 and anti-SLA autoantibodies are not detected by conventional assays in a large group of

  10. Effect of seasonal malaria chemoprevention on the acquisition of antibodies to Plasmodium falciparum antigens in Ouelessebougou, Mali.

    Science.gov (United States)

    Mahamar, Almahamoudou; Issiaka, Djibrilla; Barry, Amadou; Attaher, Oumar; Dembele, Adama B; Traore, Tiangoua; Sissoko, Adama; Keita, Sekouba; Diarra, Bacary Soumana; Narum, David L; Duffy, Patrick E; Dicko, Alassane; Fried, Michal

    2017-07-18

    Seasonal malaria chemoprevention (SMC) is a new strategy to reduce malaria burden in young children in Sahelian countries. It consists of the administration of full treatment courses of sulfadoxine-pyrimethamine plus amodiaquine to children at monthly intervals during the malaria season. However, it is not clear if there is a cumulative effect of SMC over time on acquisition of antibodies to malaria antigens. A cross-sectional serosurvey was carried out 1 month after the last dose of SMC in 2016. Children aged 3-4 years were randomly selected from areas where SMC was given for 1, 2 or 3 years during the malaria season. Children in the areas where SMC had been implemented for 1 year but who failed to receive SMC were used as comparison group. Antibody extracted from dry blood spots was used to measure IgG levels to CSP, MSP-1 42 and AMA1. The prevalence of antibodies to AMA-1 were high and similar in children who received SMC for 1, 2 or 3 years and also when compared to those who never received SMC (96.3 vs 97.5%, adjusted OR = 0.99, 95% CI 0.33-2.97, p = 0.99). The prevalence of antibodies to MSP-1 42 and to CSP were similar in children that received SMC for 1, 2 or 3 years, but were lower in these children compared to those who did not receive SMC (87.1 vs 91.2%, adjusted OR = 0.55, 95% CI 0.29-1.01, p = 0.05 for MSP-1 42 ; 79.8 vs 89.2%, adjusted OR = 0.52, 95% CI 0.30-0.90, p = 0.019 for CSP). SMC reduced seropositivity to MSP-1 42 and CSP, but the duration of SMC did not further reduce seropositivity. Exposure to SMC did not reduce the seropositivity to AMA1.

  11. 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.

  12. IGHV1-69 B cell chronic lymphocytic leukemia antibodies cross-react with HIV-1 and hepatitis C virus antigens as well as intestinal commensal bacteria.

    Directory of Open Access Journals (Sweden)

    Kwan-Ki Hwang

    Full Text Available B-cell chronic lymphocytic leukemia (B-CLL patients expressing unmutated immunoglobulin heavy variable regions (IGHVs use the IGHV1-69 B cell receptor (BCR in 25% of cases. Since HIV-1 envelope gp41 antibodies also frequently use IGHV1-69 gene segments, we hypothesized that IGHV1-69 B-CLL precursors may contribute to the gp41 B cell response during HIV-1 infection. To test this hypothesis, we rescued 5 IGHV1-69 unmutated antibodies as heterohybridoma IgM paraproteins and as recombinant IgG1 antibodies from B-CLL patients, determined their antigenic specificities and analyzed BCR sequences. IGHV1-69 B-CLL antibodies were enriched for reactivity with HIV-1 envelope gp41, influenza, hepatitis C virus E2 protein and intestinal commensal bacteria. These IGHV1-69 B-CLL antibodies preferentially used IGHD3 and IGHJ6 gene segments and had long heavy chain complementary determining region 3s (HCDR3s (≥21 aa. IGHV1-69 B-CLL BCRs exhibited a phenylalanine at position 54 (F54 of the HCDR2 as do rare HIV-1 gp41 and influenza hemagglutinin stem neutralizing antibodies, while IGHV1-69 gp41 antibodies induced by HIV-1 infection predominantly used leucine (L54 allelic variants. These results demonstrate that the B-CLL cell population is an expansion of members of the innate polyreactive B cell repertoire with reactivity to a number of infectious agent antigens including intestinal commensal bacteria. The B-CLL IGHV1-69 B cell usage of F54 allelic variants strongly suggests that IGHV1-69 B-CLL gp41 antibodies derive from a restricted B cell pool that also produces rare HIV-1 gp41 and influenza hemagglutinin stem antibodies.

  13. A novel ex vivo immunoproteomic approach characterising Fasciola hepatica tegumental antigens identified using immune antibody from resistant sheep.

    Science.gov (United States)

    Cameron, Timothy C; Cooke, Ira; Faou, Pierre; Toet, Hayley; Piedrafita, David; Young, Neil; Rathinasamy, Vignesh; Beddoe, Travis; Anderson, Glenn; Dempster, Robert; Spithill, Terry W

    2017-08-01

    A more thorough understanding of the immunological interactions between Fasciola spp. and their hosts is required if we are to develop new immunotherapies to control fasciolosis. Deeper knowledge of the antigens that are the target of the acquired immune responses of definitive hosts against both Fasciola hepatica and Fasciola gigantica will potentially identify candidate vaccine antigens. Indonesian Thin Tail sheep express a high level of acquired immunity to infection by F. gigantica within 4weeks of infection and antibodies in Indonesian Thin Tail sera can promote antibody-dependent cell-mediated cytotoxicity against the surface tegument of juvenile F. gigantica in vitro. Given the high protein sequence similarity between F. hepatica and F. gigantica, we hypothesised that antibody from F. gigantica-infected sheep could be used to identify the orthologous proteins in the tegument of F. hepatica. Purified IgG from the sera of F. gigantica-infected Indonesian Thin Tail sheep collected pre-infection and 4weeks p.i. were incubated with live adult F. hepatica ex vivo and the immunosloughate (immunoprecipitate) formed was isolated and analysed via liquid chromatography-electrospray ionisation-tandem mass spectrometry to identify proteins involved in the immune response. A total of 38 proteins were identified at a significantly higher abundance in the immunosloughate using week 4 IgG, including eight predicted membrane proteins, 20 secreted proteins, nine proteins predicted to be associated with either the lysosomes, the cytoplasm or the cytoskeleton and one protein with an unknown cellular localization. Three of the membrane proteins are transporters including a multidrug resistance protein, an amino acid permease and a glucose transporter. Interestingly, a total of 21 of the 38 proteins matched with proteins recently reported to be associated with the proposed small exosome-like extracellular vesicles of adult F. hepatica, suggesting that the Indonesian Thin Tail week

  14. The effect of circulating antigen on the biodistribution of the engineered human antibody hCTM01 in a nude mice model

    International Nuclear Information System (INIS)

    Davies, Q.; Perkins, A.C.; Frier, M.; Watson, S.; Lalani, E.N.; Symonds, E.M.

    1997-01-01

    Clinical studies are currently underway to assess the biodistribution and therapeutic potential of the genetically engineered human antibody hCTM01 directed against polymorphic epithelial mucin (PEM) in patients with ovarian carcinoma. The present study was undertaken to assess the effect of circulating PEM antigen on the biodistribution of the anti-PEM antibody in mice bearing MUC-1 transfected adenocarcinoma cell lines. Tumour xenografts were established from three cell lines: 413-BCR, which expressed antigen on the cell surface and also shed antigen into the circulation, E3P23, which expressed the antigen but did not shed into the circulation, and a negative control (410.4 MUCI). Groups of five mice were injected with 1.0 mg/kg antibody, imaged after 72 h and then sacrificed, followed by assay of tissue uptake. The results showed a clear difference in the tumour and liver uptake, with the non-secreting cell line showing almost twice the tumour uptake and approximately 20% of the liver uptake of the secreting cell line. (orig.). With 4 figs., 1 tab

  15. Selection of a novel anti-nicotine vaccine: influence of antigen design on antibody function in mice.

    Directory of Open Access Journals (Sweden)

    David C Pryde

    Full Text Available Anti-nicotine vaccines may aid smoking cessation via the induction of anti-nicotine antibodies (Ab which reduce nicotine entering the brain, and hence the associated reward. Ab function depends on both the quantity (titer and the quality (affinity of the Ab. Anti-nicotine vaccines tested previously in clinical studies had poor efficacy despite high Ab titer, and this may be due to inadequate fu