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Sample records for toxin antibody titers

  1. Toxigenic Corynebacterium ulcerans isolated from a hunting dog and its diphtheria toxin antibody titer.

    Science.gov (United States)

    Katsukawa, Chihiro; Komiya, Takako; Umeda, Kaoru; Goto, Minami; Yanai, Tokuma; Takahashi, Motohide; Yamamoto, Akihiko; Iwaki, Masaaki

    2016-03-01

    Toxigenic Corynebacterium ulcerans is a zoonotic pathogen that produces diphtheria toxin and causes a diphtheria-like illness in humans. The organism is known to infect and circulate among dogs, which can then transmit it to humans. Furthermore, previous studies have found that C. ulcerans is carried by wild animals, including game animals. In the present study, we tested hunting and companion dogs for the presence of toxigenic C. ulcerans and succeeded in isolating the bacterium from a hunting dog. Moreover, several hunting dogs had serum diphtheria antitoxin titers that were higher than the titers required for protection in humans, suggesting a history of exposure to toxigenic Corynebacterium strains. Notably, ribotyping, pulsed-field gel electrophoresis and tox gene sequencing demonstrated that the isolate from the hunting dog clustered with previously characterized C. ulcerans strains isolated from wild animals, as opposed to groups of isolates from humans and companion dogs. Interestingly, the wild animal cluster also contains an isolate from an outdoor breeding dog, which could have formed a bridge between isolates from wild animals and those from companion dogs. The results presented herein provide insight into the mechanism by which the zoonotic pathogen C. ulcerans circulates among wild animals, hunting and companion dogs, and humans. © 2016 The Societies and John Wiley & Sons Australia, Ltd.

  2. A Medical Research and Evaluation Facility (MREF) and Studies Supporting the Medical Chemical Defense Program: Task 95-39: Methods Development and Validation of Two Mouse Bioassays for Use in Quantifying Botulinum Toxins (A, B, C, D and E) and Toxin Antibody Titers

    National Research Council Canada - National Science Library

    Olson, Carl

    1997-01-01

    Ths task was conducted for the U.S. Army Medical Materiel Development Activity (USAMMDA) to validate two mouse bioassays for quantify botulinum toxin potency and neutralizing antibodies to botulimun toxins...

  3. Determination of low tetanus or diphtheria antitoxin titers in sera by a toxin neutralization assay and a modified toxin-binding inhibition test

    Directory of Open Access Journals (Sweden)

    M.H. Sonobe

    2007-01-01

    Full Text Available A method for the screening of tetanus and diphtheria antibodies in serum using anatoxin (inactivated toxin instead of toxin was developed as an alternative to the in vivo toxin neutralization assay based on the toxin-binding inhibition test (TOBI test. In this study, the serum titers (values between 1.0 and 19.5 IU measured by a modified TOBI test (Modi-TOBI test and toxin neutralization assays were correlated (P < 0.0001. Titers of tetanus or diphtheria antibodies were evaluated in serum samples from guinea pigs immunized with tetanus toxoid, diphtheria-tetanus or triple vaccine. For the Modi-TOBI test, after blocking the microtiter plates, standard tetanus or diphtheria antitoxin and different concentrations of guinea pig sera were incubated with the respective anatoxin. Twelve hours later, these samples were transferred to a plate previously coated with tetanus or diphtheria antitoxin to bind the remaining anatoxin. The anatoxin was then detected using a peroxidase-labeled tetanus or diphtheria antitoxin. Serum titers were calculated using a linear regression plot of the results for the corresponding standard antitoxin. For the toxin neutralization assay, L+/10/50 doses of either toxin combined with different concentrations of serum samples were inoculated into mice for anti-tetanus detection, or in guinea pigs for anti-diphtheria detection. Both assays were suitable for determining wide ranges of antitoxin levels. The linear regression plots showed high correlation coefficients for tetanus (r² = 0.95, P < 0.0001 and for diphtheria (r² = 0.93, P < 0.0001 between the in vitro and the in vivo assays. The standardized method is appropriate for evaluating titers of neutralizing antibodies, thus permitting the in vitro control of serum antitoxin levels.

  4. Helicobacter pylori Antibody Titer and Gastric Cancer Screening

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    Hiroshi Kishikawa

    2015-01-01

    Full Text Available The “ABC method” is a serum gastric cancer screening method, and the subjects were divided based on H. pylori serology and atrophic gastritis as detected by serum pepsinogen (PG: Group A [H. pylori (− PG (−], Group B [H. pylori (+ PG (−], Group C [H. pylori (+ PG (+], and Group D [H. pylori (− PG (+]. The risk of gastric cancer is highest in Group D, followed by Groups C, B, and A. Groups B, C, and D are advised to undergo endoscopy, and the recommended surveillance is every three years, every two years, and annually, respectively. In this report, the reported results with respect to further risk stratification by anti-H. pylori antibody titer in each subgroup are reviewed: (1 high-negative antibody titer subjects in Group A, representing posteradicated individuals with high risk for intestinal-type cancer; (2 high-positive antibody titer subjects in Group B, representing active inflammation with high risk for diffuse-type cancer; and (3 low-positive antibody titer subjects in Group C, representing advanced atrophy with increased risk for intestinal-type cancer. In these subjects, careful follow-up with intervals of surveillance of every three years in (1, every two years in (2, and annually in (3 should be considered.

  5. E.coli and investigation of antibody titer in rats

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    masoud abdollahi

    2017-03-01

    Full Text Available Introduction: Plant ribosome inactivating proteins act as N-glycosidase enzyme and produce by several family of Caryophyllaceae such as Saponaria Officinalis. Different Isoforms of RIPs expressed by Saponaria Officinalis. SO6 isoform depurinate Adenine 4324 in the conserved GAGA loop of 28SrRNA and disrupts protein synthesis. The aim of this study was expression of SO6 isoform in E.coli and investigation of antibody titer in rats. Methods: In this experimental study, SO6 synthetic gene was excised from recombinant pUC57- SO6 plasmid with BamHI and SalI restriction enzymes and subcloned into pET28a (+ expression vector. The expression of recombinant protein was induced by IPTG. Recombinant SO6 was purified by nickel affinity chromatography. Western blotting was performed to confirm the recombinant protein. Rats were immunized intraperitoneal with purified protein and IgG serum titer was assayed by ELISA. Results: PCR reaction and enzyme digestion confirmed subcloning of SO6 gene into pET28a (+ expression vector. A 29.5kDa protein band on SDS-PAGE showed a high level of recombinant protein expression. Polyclonal antibodies recognized SO6. ELISA confirmed significant antibody titer after injection of protein in test group compared with the control group. Conclusion: The recombinant purified SO6 antigen can be used for anti-cancer and vaccine candidate research.

  6. Significance of prenatal joint detection of ABO antibody titers and irregular antibodies in pregnant women with type O blood.

    Science.gov (United States)

    Zhu, W Y; Li, H X; Liang, Y

    2014-01-01

    To investigate the effects of blood transfusion and number of pregnancies on ABO antibody titers and irregular antibodies in pregnant women with type O blood. The study included 4,200 pregnant women with type O blood (their husbands were with non-O type blood) that were divided into transfusion group and non-transfusion group, according to whether they had a history of blood transfusion. The both groups were respectively divided into three subgroups (the number of pregnancies was one, two, and > or = three). The ABO antibody titers and irregular antibodies were detected at the same time. The effects ofABO antibody titers and irregular antibodies on hemolytic disease of the newborn (HDN) were discussed. There was no consistency of ABO antibody titers and existence of irregular antibody. The positive rates of irregular antibody of transfusion group and of the subgroup (number of pregnancies > or = three) were far higher than that of non-transfusion group and of the subgroups (number of pregnancies pregnant women with positive irregular antibody in non-transfusion group were with HDN. For pregnant women with number of pregnancies > or = three or with history of blood transfusion, the prenatal joint detection of ABO antibody titers and irregular antibodies is helpful for accurately reflecting the in vivo antibody type and level.

  7. Prevalence and titers of yellow fever virus neutralizing antibodies in previously vaccinated adults

    Science.gov (United States)

    Miyaji, Karina Takesaki; Avelino-Silva, Vivian Iida; Simões, Marisol; Freire, Marcos da Silva; de Medeiros, Carlos Roberto; Braga, Patrícia Emilia; Neves, Maria Angélica Acalá; Lopes, Marta Heloisa; Kallas, Esper Georges; Sartori, Ana Marli Christovam

    2017-01-01

    ABSTRACT Introduction: The World Health Organization (WHO) recommends one single dose of the Yellow Fever (YF) vaccine based on studies of antibody persistency in healthy adults. We assessed the prevalence and titers of YF virus neutralizing antibodies in previously vaccinated persons aged ≥ 60 years, in comparison to younger adults. We also evaluated the correlation between antibody titers and the time since vaccination among participants who received one vaccine dose, and the seropositivity among participants vaccinated prior to or within the past 10 years. Methods: previously vaccinated healthy persons aged ≥ 18 years were included. YF virus neutralizing antibody titers were determined by means of the 50% Plaque Reduction Neutralization Test. Results: 46 persons aged ≥ 60 years and 48 persons aged 18 to 59 years were enrolled. There was no significant difference in the prevalence of YF virus neutralizing antibodies between the two groups (p = 0.263). However, titers were significantly lower in the elderly (p = 0.022). There was no correlation between YF virus neutralizing antibody titers and the time since vaccination. There was no significant difference in seropositivity among participants vaccinated prior to or within the past 10 years. Conclusions: the clinical relevance of the observed difference in YF virus neutralizing antibody titers between the two groups is not clear. PMID:28380113

  8. Prevalence and titers of yellow fever virus neutralizing antibodies in previously vaccinated adults.

    Science.gov (United States)

    Miyaji, Karina Takesaki; Avelino-Silva, Vivian Iida; Simões, Marisol; Freire, Marcos da Silva; Medeiros, Carlos Roberto de; Braga, Patrícia Emilia; Neves, Maria Angélica Acalá; Lopes, Marta Heloisa; Kallas, Esper Georges; Sartori, Ana Marli Christovam

    2017-04-03

    The World Health Organization (WHO) recommends one single dose of the Yellow Fever (YF) vaccine based on studies of antibody persistency in healthy adults. We assessed the prevalence and titers of YF virus neutralizing antibodies in previously vaccinated persons aged  60 years, in comparison to younger adults. We also evaluated the correlation between antibody titers and the time since vaccination among participants who received one vaccine dose, and the seropositivity among participants vaccinated prior to or within the past 10 years. previously vaccinated healthy persons aged  18 years were included. YF virus neutralizing antibody titers were determined by means of the 50% Plaque Reduction Neutralization Test. 46 persons aged  60 years and 48 persons aged 18 to 59 years were enrolled. There was no significant difference in the prevalence of YF virus neutralizing antibodies between the two groups (p = 0.263). However, titers were significantly lower in the elderly (p = 0.022). There was no correlation between YF virus neutralizing antibody titers and the time since vaccination. There was no significant difference in seropositivity among participants vaccinated prior to or within the past 10 years. the clinical relevance of the observed difference in YF virus neutralizing antibody titers between the two groups is not clear.

  9. Hashimoto encephalopathy in pediatric patients: Homogeneity in clinical presentation and heterogeneity in antibody titers.

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    Lee, Jiwon; Yu, Hee Joon; Lee, Jeehun

    2018-01-01

    Hashimoto encephalopathy is an autoimmune encephalopathy characterized by elevated antithyroid antibodies and a favorable response to corticosteroid. This study delineated the clinical characteristics of pediatric Hashimoto encephalopathy and the significance of low antithyroid antibody titers in diagnosis and treatment. Clinical manifestations, antibody titers, and treatment responses were retrospectively reviewed in six consecutive children diagnosed with Hashimoto encephalopathy between August 2008 and July 2016. Age at diagnosis was 10-17years. Presenting symptoms were seizures, altered consciousness, behavioral changes, psychosis, tremor, and dystonia. Thyroid function was normal in five patients, and one had hypothyroidism prior to the encephalopathy. Antithyroid antibody titer was increased at presentation in five patients and one week later in the other. Antibody levels were extremely varied (anti-thyroglobulin, 20.5-2318.0U/ml; anti-thyroid peroxidase, 12.5-2231.0U/ml; reference range, Hashimoto encephalopathy were similar, irrespective of antithyroid antibody titer. Because the initial antithyroid antibody titers can be normal or mildly-elevated, follow-up testing of antithyroid antibodies is required in patients who are clinically suspect for Hashimoto encephalopathy. Copyright © 2017 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  10. Association of Tissue Transglutaminase Antibody Titer with Duodenal Histological Changes in Children with Celiac Disease

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    Hasan Hawamdeh

    2016-01-01

    Full Text Available Celiac disease is usually diagnosed by demonstrating gluten enteropathy in small bowel biopsy. Celiac specific antibodies are used as an initial screening test. The goal of this study is to test the relationship of the anti-tTG titer and severity of histological changes in Jordanian children with celiac disease. Method. The medical records of 81 children who had elevated anti-tTG titer and had duodenal biopsies available were retrospectively reviewed. Result. Assessing the association of anti-tTG titer with duodenal histopathological changes, 94% of those with high anti-tTG titer (≥180 U/mL had histological evidence of celiac disease. There was statistically significant positive association between high anti-tTG titer and Marsh grading as 82% of patients with Marsh III had high anti-tTG titer (Chi2 18.5; P value 0.00; Odds Ratio 8.5. The fraction of patients with Marsh III who were correctly identified as positive by anti-tTG titer ≥ 180 U/mL was high (sensitivity = 81.6. Moreover, the fraction of patients with anti-tTG titer ≥ 180 U/mL who had Marsh III was also high (positive predictive value = 78.4. Conclusion. Anti-tTG titer ≥ 180 U/mL had significant positive association with Marsh III histopathological changes of celiac disease.

  11. EFFECT OF A PREPREGNANCY PERTUSSIS BOOSTER DOSE ON MATERNAL ANTIBODY TITERS IN YOUNG INFANTS

    OpenAIRE

    Leuridan, Elke; HENS, Niel; Peeters, Natasja; de Witte, Liene; Van der Meeren, Olivier; Van Damme, Pierre

    2011-01-01

    To examine the influence of a pertussis booster vaccination on the transfer of maternal antibodies, 24 nonpregnant women received a tetanus, diphtheria, acellular pertussis booster vaccine between 2 consecutive pregnancies. Blood was drawn from mothers and off-spring. Efficient transplacental antibody transfer and significantly higher antibody titers against 3 pertussis antigens were observed in cord blood and in blood of 1-month-old infants born after a maternal booster vaccination compared ...

  12. IVIg treatment reduces catalytic antibody titers of renal transplanted patients.

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    Ankit Mahendra

    Full Text Available Catalytic antibodies are immunoglobulins endowed with enzymatic activity. Catalytic IgG has been reported in several human autoimmune and inflammatory diseases. In particular, low levels of catalytic IgG have been proposed as a prognostic marker for chronic allograft rejection in patients undergoing kidney transplant. Kidney allograft is a treatment of choice for patients with end-stage renal failure. Intravenous immunoglobulins, a therapeutic pool of human IgG, is used in patients with donor-specific antibodies, alone or in conjunction with other immunosuppressive treatments, to desensitize the patients and prevent the development of acute graft rejection. Here, we followed for a period of 24 months the levels of catalytic IgG towards the synthetic peptide Pro-Phe-Arg-methylcoumarinimide in a large cohort of patients undergoing kidney transplantation. Twenty-four percent of the patients received IVIg at the time of transplantation. Our results demonstrate a marked reduction in levels of catalytic antibodies in all patients three months following kidney transplant. The decrease was significantly pronounced in patients receiving adjunct IVIg therapy. The results suggests that prevention of acute graft rejection using intravenous immunoglobulins induces a transient reduction in the levels of catalytic IgG, thus potentially jeopardizing the use of levels of catalytic antibodies as a prognosis marker for chronic allograft nephropathy.

  13. IVIg Treatment Reduces Catalytic Antibody Titers of Renal Transplanted Patients

    Science.gov (United States)

    Mahendra, Ankit; Peyron, Ivan; Dollinger, Cécile; Gilardin, Laurent; Sharma, Meenu; Wootla, Bharath; Padiolleau-Lefevre, Séverine; Friboulet, Alain; Boquet, Didier; Legendre, Christophe; Kaveri, Srinivas V.

    2013-01-01

    Catalytic antibodies are immunoglobulins endowed with enzymatic activity. Catalytic IgG has been reported in several human autoimmune and inflammatory diseases. In particular, low levels of catalytic IgG have been proposed as a prognostic marker for chronic allograft rejection in patients undergoing kidney transplant. Kidney allograft is a treatment of choice for patients with end-stage renal failure. Intravenous immunoglobulins, a therapeutic pool of human IgG, is used in patients with donor-specific antibodies, alone or in conjunction with other immunosuppressive treatments, to desensitize the patients and prevent the development of acute graft rejection. Here, we followed for a period of 24 months the levels of catalytic IgG towards the synthetic peptide Pro-Phe-Arg-methylcoumarinimide in a large cohort of patients undergoing kidney transplantation. Twenty-four percent of the patients received IVIg at the time of transplantation. Our results demonstrate a marked reduction in levels of catalytic antibodies in all patients three months following kidney transplant. The decrease was significantly pronounced in patients receiving adjunct IVIg therapy. The results suggests that prevention of acute graft rejection using intravenous immunoglobulins induces a transient reduction in the levels of catalytic IgG, thus potentially jeopardizing the use of levels of catalytic antibodies as a prognosis marker for chronic allograft nephropathy. PMID:23967092

  14. Antiphospholipid Antibody Titers and Clinical Outcomes in Patients with Recurrent Miscarriage and Antiphospholipid Antibody Syndrome: A Prospective Study

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    Yu Song

    2017-01-01

    Conclusions: Anti-β2-GP1 IgM was the predominant form of antibody in patients with RM and APS. The decreases in antiphospholipid antibody titers correlated with better pregnancy outcomes. The shorter treatment regimen was effective and economical.

  15. Activity, specificity, and titer of naturally occurring canine anti-DEA 7 antibodies.

    Science.gov (United States)

    Spada, Eva; Proverbio, Daniela; Baggiani, Luciana; Canzi, Ilaria; Perego, Roberta

    2016-11-01

    The reported prevalence of naturally occurring anti-dog erythrocyte antigen (DEA) 7 antibodies in DEA 7-negative dogs is as high as 50%. Characterization of these antibodies may better define their importance in canine transfusion medicine. We determined in vitro activity, specificity, and titer of anti-DEA 7 antibodies in DEA 7-negative dogs. Plasma samples from 317 DEA 7-negative dogs were cross-matched with DEA 7-positive red blood cells (RBCs) using gel column technology. Agglutination occurred with DEA 7-positive RBCs but not with DEA 7-negative RBCs in 73 samples (23%), which were hence classified as containing anti-DEA 7 antibodies. These samples were evaluated for hemolytic and agglutinating activity, strength of agglutination, and antibody specificity and titers. All samples showed agglutination but none showed hemolysis. Gel agglutination was graded as 1+ for 20 samples (27%), 2+ for 49 samples (67%), 3+ for 4 samples (6%); no samples were graded 4+. The agglutination titer was DEA 7 antibodies were found in 23% of DEA 7-negative dogs. The presence of naturally occurring anti-DEA 7 antibodies suggests that cross-matching of canine blood recipients is advisable, even at first transfusion, to minimize delayed transfusion reactions. © 2016 The Author(s).

  16. Genetic parameters for natural antibody isotype titers in milk of Dutch Holstein-Friesians

    NARCIS (Netherlands)

    Wijga, S.; Bovenhuis, H.; Bastiaansen, J.W.M.; Arendonk, van J.A.M.; Ploegaert, T.C.W.; Tijhaar, E.; Poel, van der J.J.

    2013-01-01

    The objective of the present study was to estimate genetic parameters for natural antibody isotypes immunoglobulin (Ig) A, IgG1 and IgM titers binding the bacterial antigens lipopolysaccharide, peptidoglycan and the model antigen keyhole limpet hemocyanin in Dutch Holstein-Friesian cows (n = 1695).

  17. Emotional Disclosure through Writing or Speaking Modulates Latent Epstein-Barr Virus Antibody Titers.

    Science.gov (United States)

    Esterling, Brian A.; And Others

    1994-01-01

    Healthy Epstein-Barr virus (EBV) seropositive undergraduates (n=57) completed personality inventory, provided blood samples, and were randomly assigned to write/talk about stressful events, or to write about trivial events. Those assigned to verbal/stressful condition had significantly lower EBV antibody titers (suggesting better cellular immune…

  18. Ekstrak Pegagan Meningkatkan Titer Antibodi Mencit Setelah Diinfeksi Salmonella typhi (CENTELLA ASIATICA EXTRACT INCREASE ANTIBODY TITER IN MICE AFTER SALMONELLA TYPHI INFECTION

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    I Nengah Kerta Besung

    2013-09-01

    Full Text Available A study was conducted to find out the ability of Centella asiatica (C. asiatica in enhancing antibodyresponse of C. asiatica treated mice following Salmonella typhi (S. typhi infections. It is therefore expectedthat herbal drug such as  C. asiatica  can be used as an alternative medicine to prevent and to curesalmonellosis both in animals and human. Experimental laboratory studies were conducted usingCompletely Factorial Randomized Design. Mice were divided into four groups and they were treatedrespectively with destilated water (negative control, 125, 250, and 500 mg/kg BW/day of  C. asiaticaextract. The treatment was conducted daily for two weeks  and the mice were inoculated with 105 cells/mlof  S. typhi. The antibody response were examined by indirect enzyme-linked immunosorbent assay (ELISAon first day, second week and fourth week  after S. typhi infections.  The result showed that treatment ofmice with C. asiatica extract significantly (p<0,05 enhanced antibody titer of Balb/c mice after S. typhiinfections. The highest antibody titer was observed at four weeks after S. typhi infections with 500 mg/kgBW/day (94,0370 ± 1,69 IU.

  19. An improved method for estimating antibody titers in microneutralization assay using green fluorescent protein.

    Science.gov (United States)

    Yang, Hongmei; Baker, Steven F; González, Mario E; Topham, David J; Martínez-Sobrido, Luis; Zand, Martin; Holden-Wiltse, Jeanne; Wu, Hulin

    2016-01-01

    Viruses that express reporter genes upon infection have been recently used to evaluate neutralizing antibody responses, where a lack of reporter expression indicates specific virus inhibition. The traditional model-based methods using standard outcome of percent neutralization could be applied to the data from the assays to estimate antibody titers. However, the data produced are sometimes irregular, which can yield meaningless outcomes of percent neutralization that do not fit the typical curves for immunoassays, making automated or semi-high throughput antibody titer estimation unreliable. We developed a type of new outcomes model, which is biologically meaningful and fits typical immunoassay curves well. Our simulation study indicates that the new response approach outperforms the traditional response approach regardless of the data variability. The proposed new response approach can be used in similar assays for other disease models.

  20. Evaluation of neutralizing antibodies to type A, B, E, and F botulinum toxins in sera from human recipients of botulinum pentavalent (ABCDE) toxoid.

    Science.gov (United States)

    Siegel, L S

    1989-08-01

    Twenty-five serum specimens from personnel immunized with botulinum pentavalent toxoid (ABCDE) had titers of neutralizing antibodies to type A (5.7 to 51.6 IU/ml), type B (0.75 to 18 IU/ml), and type E (0.61 to 10 IU/ml) botulinum toxins. Titers for one type could not be used to predict titers for another type in individuals receiving the toxoid. Cross-neutralizing antibodies to type F botulinum toxin were not detected (less than 0.0125 IU/ml).

  1. Antibody titers for canine parvovirus type-2, canine distemper virus, and canine adenovirus type-1 in adult household dogs.

    Science.gov (United States)

    Taguchi, Masayuki; Namikawa, Kazuhiko; Maruo, Takuya; Orito, Kensuke; Lynch, Jonathan; Sahara, Hiroeki

    2011-09-01

    Serum antibody titers for canine parvovirus type-2 (CPV-2), canine distemper virus (CDV) and canine adenovirus type-1 (CAV-1) were investigated in 1031 healthy adult household dogs (2 to 18 years old) given an annual inoculation in the previous 11 to 13 months. The number of dogs retaining significant titers of antibodies against CPV-2, CDV, and CAV-1 were 888 (86%), 744 (72%), and 732 (71%), respectively. There were no differences between males and females in antibody titers against the 3 viruses. Antibody titer for CPV-2 was significantly higher in younger dogs than in older dogs, CDV antibody was significantly higher in older dogs than in younger dogs, and CAV titer was not associated with age.

  2. ABO-Incompatible Renal Transplantation with High Antibody Titer: A Case Report.

    Science.gov (United States)

    Ray, Deepak Shankar; Thukral, Sharmila

    2017-10-06

    BACKGROUND Even though renal transplantation across blood groups is not uncommonly practiced nowadays, there is still hesitation regarding ABO-incompatible transplantation with very high baseline antibody titer. In this case report, the outcome of an ABO-incompatible kidney transplant recipient with a high baseline isoagglutinin titer is reported. CASE REPORT The patient was a non-diabetic, 33-year-old man with end-stage renal disease secondary to chronic glomerulonephritis. The only kidney donor available was his mother, who was blood-group incompatible. The patient's blood group was O positive, whereas his mother was B positive. We evaluated him for an ABO-incompatible renal transplant. The baseline anti-B isoagglutinin titer was >1:8196.  With a desensitization protocol of low-dose Rituximab, plasmapheresis, and IVIG, this titer was brought down to 1:32 before transplantation. He successfully underwent renal transplantation across the ABO barrier, and maintains good graft function after 1 year of follow-up.  CONCLUSIONS In the present era, a high baseline isoagglutinin titer is no longer a contraindication for successful kidney transplantation in ABO-incompatible recipient-donor pairs.

  3. Proposed method for agglutinating antibody titer analysis and its use as indicator of acquired immunity in pacu, Piaractus mesopotamicus

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    JD Biller-Takahashi

    Full Text Available Antibody can be assessed by agglutinating antibody titer which is a quantitative measure of circulating antibodies in serum from fish previously immunized. The antibody evaluation has been performed with different fish species, and is considered a reliable method that can be applied to confirm several hypothesis regarding acquired immunity, even in conjunction with precise methods to describe immune mechanisms. In order to provide appropriate analytical methods for future studies on the specific immune system of native fish, the present study standardized on assay to measure the serum agglutinating antibody titer produced after immunization with inactivated A. hydrophila and levamisole administration in pacu. It was possible to determine the agglutinating antibodies titer in a satisfactorily way in pacu immunized with inactive A. hydrophila, and the highest titers were observed on fish fed with levamisole.

  4. Prevalence of antibody titers to leptospira spp. in Minnesota white-tailed deer

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    Goyal, S.M.; Mech, L.D.; Nelson, M.E.

    1992-01-01

    Serum samples (n = 204) from 124 white-tailed deer (Odocoileus virginianus) in northeastern Minnesota (USA) were collected from 1984 through 1989 and tested for antibodies to six serovars of Leptospira interrogans (bratislava, canicola, grippotyphosa, hardjo, icterohemorrhagiae, and pomona) using a microtiter agglutination test. Eighty-eight (43%) sera were positive at greater than or equal to 1:100 for antibodies against serovars pomona and/or bratislava; none was positive for any of the other four serovars. None of the 31 sera collected in 1984-85 was positive, whereas all 54 sera collected from 1986 through 1988 had titers of greater than or equal to 1:100. During 1989, only 34 (29%) of 119 sera had titers of greater than or equal to 1:100. Based on these results, we believe there to be wide variability in exposure of Minnesota deer to Leptospira interrogans.

  5. Interference of daratumumab with pretransfusion testing, mimicking a high-titer, low avidity like antibody

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    Mei-Hwa Lin

    2017-01-01

    Full Text Available Daratumumab is a monoclonal immunoglobulin against CD38 and has been approved for treating patients with refractory multiple myeloma. The presence of daratumumab in the sera can interfere with pretransfusion testing due to the weakly expression of CD38 on red cells. The reactivity could be mistaken as autoantibody (if autocontrol is positive or alloantibody (if autocontrol is negative. We present a case that demonstrates daratumumab could mimic a high titer low avidity (HTLA alloantibody. A 34-year-old male patient of refractory myeloma was recruited in phase three clinical trial involving daratumumab. Samples were sent to the blood bank for pretransfusion testing. Without knowledge of patient having used daratumumab, we mistook the reactivity in the patient's sera as an HTLA antibody due to the results of negative autocontrol and high titers of antibody activity. Antibody screen showed a panreactive pattern and the reactivity against screening cells was up to a titer of 1: 1240. The reactivity was weaker against cord cells than adult cells, became weaker against ZZAP-treated cells and became negative against DDT-treated cells. A discussion with attending physician finally revealed the reactivity was due to the interference caused by daratumumab. The case demonstrates good communication is essential in performing pretransfusion testing for patients receiving daratumumab and other new biological regimens that can interfere with compatibility test.

  6. Interference of daratumumab with pretransfusion testing, mimicking a high-titer, low avidity like antibody.

    Science.gov (United States)

    Lin, Mei-Hwa; Liu, Fei-Yun; Wang, Hsiu-Mien; Cho, Hsin-Ching; Lo, Shyh-Chyi

    2017-01-01

    Daratumumab is a monoclonal immunoglobulin against CD38 and has been approved for treating patients with refractory multiple myeloma. The presence of daratumumab in the sera can interfere with pretransfusion testing due to the weakly expression of CD38 on red cells. The reactivity could be mistaken as autoantibody (if autocontrol is positive) or alloantibody (if autocontrol is negative). We present a case that demonstrates daratumumab could mimic a high titer low avidity (HTLA) alloantibody. A 34-year-old male patient of refractory myeloma was recruited in phase three clinical trial involving daratumumab. Samples were sent to the blood bank for pretransfusion testing. Without knowledge of patient having used daratumumab, we mistook the reactivity in the patient's sera as an HTLA antibody due to the results of negative autocontrol and high titers of antibody activity. Antibody screen showed a panreactive pattern and the reactivity against screening cells was up to a titer of 1: 1240. The reactivity was weaker against cord cells than adult cells, became weaker against ZZAP-treated cells and became negative against DDT-treated cells. A discussion with attending physician finally revealed the reactivity was due to the interference caused by daratumumab. The case demonstrates good communication is essential in performing pretransfusion testing for patients receiving daratumumab and other new biological regimens that can interfere with compatibility test.

  7. Association between Gastric Cancer Risk and Serum Helicobacter pylori Antibody Titers

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    Mitsutaka Shuto

    2017-01-01

    Full Text Available Background/Aims. It is difficult to confirm the accurate cutoff value to diagnose Helicobacter pylori (Hp infection using commercial serology kits. It is reported that there were many cases with present/past infection that even the serum Hp-IgG antibody (HpAb titers were below the cutoff value (e.g., 10 U/mL for E-Plate®, suggesting that we might overlook many gastric cancer (GC. We investigated an association between gastric cancer risk and serum Helicobacter pylori antibody titers. Methods. We conducted a primary screening between 2014 and 2015. We performed gastroendoscopy if HpAb titers were ≥3.0 U/mL (i.e., more than measurable limit, E-Plate. These patients were divided into two groups: HpAb = 3.0–9.9 U/mL (“negative-high” group and HpAb ≥ 10 U/mL; cutoff value (“over-10 U/mL” group. Hp infection status was investigated, and the number of GC patients was counted. Results. Among the 3321 subjects in the primary screening, 56.9% (1891/3321 showed HpAb titers ≥3.0 U/mL; 1314 patients underwent gastroendoscopy. Ten were GC. 421 patients were “negative-high” group; two were GC. After evaluating 381 patients for Hp infection, 22.6%/60.6% was with present/past infection among the “negative-high” group. Conclusion. We also found a correlation between HpAb titers and Hp infection status. “Negative-high” group has a risk of GC.

  8. Antiphospholipid Antibody Titers and Clinical Outcomes in Patients with Recurrent Miscarriage and Antiphospholipid Antibody Syndrome: A Prospective Study

    Science.gov (United States)

    Song, Yu; Wang, Hai-Yan; Qiao, Jie; Liu, Ping; Chi, Hong-Bin

    2017-01-01

    Background: The management of patients with recurrent miscarriage (RM) and antiphospholipid antibody syndrome (APS) includes prolonged treatment with heparin and aspirin, starting from the confirmation of pregnancy and continuing until 6 weeks after birth. This study was conducted to determine the relationship between changes in antiphospholipid antibody titers and clinical outcomes. The effect of a shortened treatment regimen was also evaluated. Methods: A prospective study of 123 patients with RM and APS between March 2012 and May 2014 was conducted. Patients were pretreated with a low dose of prednisone plus aspirin before pregnancy, and heparin was added after conception. The levels of antiphospholipid antibodies and pregnancy outcomes were evaluated. Results: All patients were positive for anti-β2-glycoprotein 1 (anti-β2-GP1) IgM. After prepregnancy treatment with low-dose prednisone plus aspirin, 99 of 123 patients became pregnant, and 87 of those pregnancies resulted in successful live births, while 12 resulted in miscarriage, showing a success rate of 87.9%. In the live birth group, levels of anti-β2-GP1 were 56.8 ± 49.0 RU/ml before the pretreatment regimen, 32.1 ± 26.0 RU/ml after 2 months of pretreatment, and 24.1 ± 23.1 RU/ml during early pregnancy (P antiphospholipid antibody titers were 52.8 ± 30.7 RU/ml before pretreatment, 38.5 ± 34.2 RU/ml after pretreatment, and 33.9 ± 24.7 RU/ml during early pregnancy; the decrease in antiphospholipid antibodies was lower in the miscarriage group than in the live birth group (P antiphospholipid antibody titers correlated with better pregnancy outcomes. The shorter treatment regimen was effective and economical. PMID:28139508

  9. Prognosis of periodontitis recurrence after intensive periodontal treatment using examination of serum IgG antibody titer against periodontal bacteria.

    Science.gov (United States)

    Sugi, Noriko; Naruishi, Koji; Kudo, Chieko; Hisaeda-Kako, Aya; Kono, Takayuki; Maeda, Hiroshi; Takashiba, Shogo

    2011-01-01

    Chronic periodontitis is associated with systemic diseases such as atherosclerosis. In this study, we evaluated the efficacy of serum IgG antibody titer to periodontal bacteria for prognosis of periodontitis recurrence during supportive periodontal therapy (SPT) phase. The 139 patients during SPT phase were selected and divided to two groups as follows: "Stable" and "Recurrence" group at SPT phase for case-control study: "High IgG titer" and "Normal IgG titer" group before transition to SPT phase for cohort study. We examined whether clinical findings or serum IgG antibody titers to periodontal bacteria are risk factors for the development of periodontitis recurrence. Case-control study showed that there were significant differences between the stable and recurrence groups in age and number of teeth. The serum IgG antibody titer to Eikenella corrodens FDC1073, Porphyromonas gingivalis SU63, and Campylobacter rectus ATCC33238 was significantly higher in the recurrence group. Next, we found, that the recurrence ratio in the high IgG titer group to Gram-negative obligate anaerobe, Prevotella intermedia, Treponema denticola, and C. rectus was significantly higher than that of the normal IgG titer group. Taken together, serum IgG antibody titer test is useful in the prognosis of periodontitis recurrence during the SPT phase. © 2011 Wiley-Liss, Inc.

  10. CANINE DISTEMPER VIRUS ANTIBODY TITERS IN DOMESTIC CATS AFTER DELIVERY OF A LIVE ATTENUATED VIRUS VACCINE.

    Science.gov (United States)

    Ramsay, Edward; Sadler, Ryan; Rush, Robert; Seimon, Tracie; Tomaszewicz, Ania; Fleetwood, Ellen A; McAloose, Denise; Wilkes, Rebecca P

    2016-06-01

    Three methods for delivering a live attenuated canine distemper virus (CDV) vaccine to domestic cats ( Felis catus ) were investigated, as models for developing vaccination protocols for tigers (Panthera tigris). Twenty domestic cats were randomly divided into four treatment groups: saline injection (negative controls); and oral, intranasal, and subcutaneous vaccinates. Cats were injected with saline or a CDV vaccine (Nobivac DP, Merck) at wk 0 and 4. Blood and nasal swabs were collected at wk 0 (prior to the initial vaccination) and weekly thereafter for 9 wk. Urine samples were collected on wk 1 to 9 after initial vaccination. Forty-nine weeks following the initial vaccination series, three cats from the subcutaneous group and three cats from the intranasal group were revaccinated. Blood was collected immediately prior, and 7 and 21 days subsequent to revaccination. Nasal swabs and urine samples were collected from each cat prior to wk 49 revaccination and daily for 7 days thereafter. Nasal swabs and urine were analyzed by quantitative PCR for vaccine virus presence. Sera were tested for CDV antibodies by virus neutralization. All cats were sero-negative for CDV antibodies at the beginning of the study, and saline-injected cats remained sero-negative throughout the study. A dramatic anamnestic response was seen following wk 4 subcutaneous vaccinations, with titers peaking at wk 6 (geometric mean = 2,435.5). Following wk 49 revaccination, subcutaneous vaccinates again mounted impressive titers (wk 52 geometric mean = 2,048). Revaccination of the intranasal group cats at wk 49 produced a small increase in titers (wk 52 geometric mean = 203). CDV viral RNA was detected in six nasal swabs but no urine samples, demonstrating low viral shedding postvaccination. The strong antibody response to subcutaneous vaccination and the lack of adverse effects suggest this vaccine is safe and potentially protective against CDV infection in domestic cats.

  11. Study of the titers of Anti-Epstein-Barr virus antibodies in the sera of atomic bomb survivors

    International Nuclear Information System (INIS)

    Akiyama, Mitoshi; Kusunoki, Yoichiro; Kyoizumi, Seishi; Ozaki, Kyoko; Mizuno, Shoichi; Cologne, J.B.

    1993-01-01

    Antibody titers to Epstein-Barr virus antigens were determined in the sera of 372 atomic bomb survivors to evaluate the effect of the previous radiation exposure on immune competence against the latent infection of the virus. The proportion of persons with high titers (≥ 1:40) of IgG antibodies to the early antigen was significantly elevated in the exposed survivors. Furthermore, the distribution of IgM titers against the viral capsid antigen was significantly affected by radiation dose with an increased occurrence of titers of 1:5 and 1:10 in the exposed persons, although the dose effect was only marginally suggestive when persons with rheumatoid factor were eliminated from the analysis. These results suggest that reactivation of Epstein-Barr virus in the latent stage occurs more frequently in the survivors, even though this might not be affected by the radiation dose. Otherwise, there was neither an increased trend in the prevalence of high titers (≥ 1:640) of IgG antibodies to the viral capsid antigen among the exposed people nor a correlation between the radiation exposure and distributions of titers of IgA antibodies to the viral capsid antigen or antibodies to the anti-Epstein-Barr virus-associated nuclear antigen. (author)

  12. Early low-titer neutralizing antibodies impede HIV-1 replication and select for virus escape.

    Directory of Open Access Journals (Sweden)

    Katharine J Bar

    Full Text Available Single genome sequencing of early HIV-1 genomes provides a sensitive, dynamic assessment of virus evolution and insight into the earliest anti-viral immune responses in vivo. By using this approach, together with deep sequencing, site-directed mutagenesis, antibody adsorptions and virus-entry assays, we found evidence in three subjects of neutralizing antibody (Nab responses as early as 2 weeks post-seroconversion, with Nab titers as low as 1∶20 to 1∶50 (IC(50 selecting for virus escape. In each of the subjects, Nabs targeted different regions of the HIV-1 envelope (Env in a strain-specific, conformationally sensitive manner. In subject CH40, virus escape was first mediated by mutations in the V1 region of the Env, followed by V3. HIV-1 specific monoclonal antibodies from this subject mapped to an immunodominant region at the base of V3 and exhibited neutralizing patterns indistinguishable from polyclonal antibody responses, indicating V1-V3 interactions within the Env trimer. In subject CH77, escape mutations mapped to the V2 region of Env, several of which selected for alterations of glycosylation. And in subject CH58, escape mutations mapped to the Env outer domain. In all three subjects, initial Nab recognition was followed by sequential rounds of virus escape and Nab elicitation, with Nab escape variants exhibiting variable costs to replication fitness. Although delayed in comparison with autologous CD8 T-cell responses, our findings show that Nabs appear earlier in HIV-1 infection than previously recognized, target diverse sites on HIV-1 Env, and impede virus replication at surprisingly low titers. The unexpected in vivo sensitivity of early transmitted/founder virus to Nabs raises the possibility that similarly low concentrations of vaccine-induced Nabs could impair virus acquisition in natural HIV-1 transmission, where the risk of infection is low and the number of viruses responsible for transmission and productive clinical

  13. Recombinant influenza H7 hemagglutinins induce lower neutralizing antibody titers in mice than do seasonal hemagglutinins.

    Science.gov (United States)

    Blanchfield, Kristy; Kamal, Ram P; Tzeng, Wen-Pin; Music, Nedzad; Wilson, Jason R; Stevens, James; Lipatov, Aleksander S; Katz, Jacqueline M; York, Ian A

    2014-11-01

    Vaccines against avian influenza viruses often require high hemagglutinin (HA) doses or adjuvants to achieve serological titers associated with protection against disease. In particular, viruses of the H7 subtype frequently do not induce strong antibody responses following immunization. To evaluate whether poor immunogenicity of H7 viruses is an intrinsic property of the H7 hemagglutinin. We compared the immunogenicity, in naïve mice, of purified recombinant HA from two H7 viruses [A/Netherlands/219/2003(H7N7) and A/New York/107/2003(H7N2)] to that of HA from human pandemic [A/California/07/2009(H1N1pdm09)] and seasonal [A/Perth16/2009(H3N2)] viruses. After two intramuscular injections with purified hemagglutinin, mice produced antibodies to all HAs, but the response to the human virus HAs was greater than to H7 HAs. The difference was relatively minor when measured by ELISA, greater when measured by hemagglutination inhibition assays, and more marked still by microneutralization assays. H7 HAs induced little or no neutralizing antibody response in mice at either dose tested. Antibodies induced by H7 were of significantly lower avidity than for H3 or H1N1pdm09. We conclude that H7 HAs may be intrinsically less immunogenic than HA from seasonal human influenza viruses. © 2014 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

  14. The role of Campylobacter jejuni cytolethal distending toxin in gastroenteritis: toxin detection, antibody production, and clinical outcome

    Energy Technology Data Exchange (ETDEWEB)

    Boisen, Nadia [University of Virginia School of Medicine

    2011-01-01

    The role of Campylobacter jejuni cytolethal distending toxin (CDT) on clinical outcome after gastroenteritis was investigated. Clinical data, blood serum samples, and Campylobacter spp. isolated, from each of 30 patients were collected over a period of 6 months. The CDT encoding genes, cdtABC, characterized by PCR, revealed that all but one of the C. jejuni strains had the wild-type sequence. Sequencing of cdtABC from this strain showed two major deletions. From all of the strains, CDT titers were determined, and toxin neutralizing antibodies were documented using an in vitro assay. Three of the thirty clinical isolates, including the one with the mutant cdtABC coding genes, did not have a detectable CDT activity. Analyzing the relationship between CDT titer, serum neutralization of CDT, and the clinical outcome showed that campylobacteriosis caused by CDT-negative strains was clinically indistinguishable from that of patients infected with an isolate that produced high levels of CDT. These results suggest that CDT does not solely determine severity of infection and clinical outcome.

  15. The role of Campylobacter jejuni cytolethal distending toxin in gastroenteritis: toxin detection, antibody production, and clinical outcome.

    Science.gov (United States)

    Mortensen, Ninell P; Schiellerup, Peter; Boisen, Nadia; Klein, Bjarke M; Locht, Henning; Abuoun, Manal; Newell, Diane; Krogfelt, Karen A

    2011-09-01

    The role of Campylobacter jejuni cytolethal distending toxin (CDT) on clinical outcome after gastroenteritis was investigated. Clinical data, blood serum samples, and Campylobacter spp. isolated, from each of 30 patients were collected over a period of 6 months. The CDT encoding genes, cdtABC, characterized by PCR, revealed that all but one of the C. jejuni strains had the wild-type sequence. Sequencing of cdtABC from this strain showed two major deletions. From all of the strains, CDT titers were determined, and toxin neutralizing antibodies were documented using an in vitro assay. Three of the thirty clinical isolates, including the one with the mutant cdtABC coding genes, did not have a detectable CDT activity. Analyzing the relationship between CDT titer, serum neutralization of CDT, and the clinical outcome showed that campylobacteriosis caused by CDT-negative strains was clinically indistinguishable from that of patients infected with an isolate that produced high levels of CDT. These results suggest that CDT does not solely determine severity of infection and clinical outcome. © 2011 The Authors. APMIS © 2011 APMIS.

  16. Discovery Of Human Antibodies Against Spitting Cobra Toxins

    DEFF Research Database (Denmark)

    Bojsen-Møller, Laura; Lohse, Brian; Harrison, Robert

    Current snakebite envenoming treatment options consist of animal-derived antisera and are associated with severe adverse reactions due to the heterologous nature of the animal-derived antibodies present in these antisera, and the presence of therapeutically irrelevant antibodies. The African...... spitting cobras are among the most medically important snakes in sub-Saharan regions due to the severity of the clinical outcomes caused by their cytotoxic venom, which is derived from cytotoxins of the 3FTx toxin family and PLA2. Here we report the results of our progress in identifying human antibodies...... targeting relevant toxins from the venom of the black necked spitting cobra (Naja nigricolis)....

  17. A high seroprevalence of antibodies to pertussis toxin among Japanese adults: Qualitative and quantitative analyses.

    Directory of Open Access Journals (Sweden)

    Takumi Moriuchi

    Full Text Available In 2013, national serosurveillance detected a high seroprevalence of antibodies to pertussis toxin (PT from Bordetella pertussis among Japanese adults. Thus, we aimed to determine the cause(s of this high seroprevalence, and analyzed the titers of antibodies to PT and filamentous hemagglutinin (FHA among adults (35-44 years old, young children (4-7 years old, and older children (10-14 years old. Our quantitative analyses revealed that adults had higher seroprevalences of anti-PT IgG and PT-neutralizing antibodies, and similar titers of anti-FHA IgG, compared to the young and older children. Positive correlations were observed between the titers of PT-neutralizing antibodies and anti-PT IgG in all age groups (rs values of 0.326-0.522, although the correlation tended to decrease with age. The ratio of PT-neutralizing antibodies to anti-PT IgG was significantly different when we compared the serum and purified IgG fractions among adults (p = 0.016, although this result was not observed among young and older children. Thus, it appears that some adults had non-IgG immunoglobulins to PT. Our analyses also revealed that adults had high-avidity anti-PT IgG (avidity index: 63.5%, similar results were observed among the children; however, the adults had lower-avidity anti-FHA IgG (37.9%, p < 0.05. It is possible that low-avidity anti-FHA IgG is related to infection with other respiratory pathogens (e.g., Bordetella parapertussis, Haemophilus influenzae, or Mycoplasma pneumoniae, which produces antibodies to FHA-like proteins. Our observations suggest that these adults had been infected with B. pertussis and other pathogen(s during their adulthood.

  18. The associations of viral and mycoplasmal antibody titers with respiratory disease and weight gain in feedlot calves.

    Science.gov (United States)

    Martin, S W; Nagy, E; Armstrong, D; Rosendal, S

    1999-08-01

    Blood samples from 32 groups of calves (n = 700) were taken on arrival and after 28-35 days at the feedlot. Eleven groups were housed in feedlots in Ontario, and 21 groups in feedlots in Alberta. Serum antibody titers to bovine viral diarrhea virus (BVDV), bovine respiratory syncytial virus (BRSV), parainfluenza virus type 3 (PIV-3), infectious bovine rhinotracheitis virus (IBRV), Mycoplasma dispar and M. bovis, plus data on bovine corona virus (BCV) from a previous study were investigated for their association with the risk of bovine respiratory disease (BRD), and with 28-day weight change, both before and after controlling for titers to Pasteurella haemolytica and Haemophilus somnus. Exposure to IBRV and M. bovis was infrequent, and although exposure to PIV-3 was more common, none of these agents had important associations with BRD. Higher titers to BVDV, BRSV, and BCV on arrival were associated with reduced risks of BRD and increased weight gains. However, there was some variation in these relationships and higher arrival titers to BVDV and BRSV in a subset of the calves were associated with increased risks of BRD. Titer increases to BVDV were associated with a higher risk of BRD and lower weight gains. Titer increases to BRSV were not usually associated with the occurrence of BRD, but titer increases to BRSV in a subset of calves that were vaccinated against BRSV, on arrival, were associated with an elevated risk of BRD. Of all the agents studied, BVDV had the most consistent associations with elevated risk of BRD and lower weight gains. Higher BRSV arrival titers were related to lower risk of BRD and higher weight gains; in some instances titer increases to BRSV were associated with higher BRD risk. Higher titers to BCV on arrival were related to reduced risks of BRD. Practical ways of adequately preventing the negative effects of these agents are still needed.

  19. H9N2 avian influenza virus antibody titers in human population in fars province, Iran

    Directory of Open Access Journals (Sweden)

    MM Hadipour

    2010-09-01

    Full Text Available Among the avian influenza A virus subtypes, H5N1 and H9N2 viruses have the potential to cause an influenza pandemic because they are widely prevalent in avian species in Asia and have demonstrated the ability to infect humans. This study was carried out to determined the seroprevalence of H9N2 avian influenza virus in different human populations in Fars province, which is situated in the south of Iran. Antibodies against H9N2 avian influenza virus were measured using hemagglutination-inhibition (HI test in sera from 300 individuals in five different population in Fars province, including poultry-farm workers, slaughter-house workers, veterinarians, patients with clinical signs of respiratory disease, and clinically normal individuals, who were not or rarely in contact with poultry. Mean antibody titers of 7.3, 6.8, 6.1, 4.5, and 2.9 and seroprevalences of 87%, 76.2%, 72.5%, 35.6%, and 23% were determined in those groups, respectively. Higher prevalences were detected in poultry-farm workers, slaughter-house workers, and veterinarians, possibly due to their close and frequent contact with poultry.

  20. The road to toxin-targeted therapeutic antibodies.

    Science.gov (United States)

    Kozel, Thomas R

    2014-07-08

    Once an infection by a toxin-producing bacterium is well established, therapies such as antibiotics that target bacterial growth may have little impact on the ultimate patient outcome. In such cases, toxin-neutralizing antibodies offer an opportunity to block key virulence factors. New work by A. K. Varshney, X. Wang, J. L. Aguilar, M. D. Scharff, and B. C. Fries [mBio 5(3):e01007-14, 2014, doi:10.1128/mBio.01007-14] highlights the role of the antibody isotype in determining the efficacy of toxin-neutralizing antibodies in vivo. Varshney et al. examined the role of antibody isotype for protection in murine models of staphylococcal enterotoxin B (SEB)-induced lethal shock and sepsis produced by SEB-producing Staphylococcus aureus. Murine antibodies of the IgG2a isotype were more protective than antibodies of the IgG1 and IgG2b isotypes that have identical variable regions and binding activity. These results add to the complexity inherent in the selection and optimization of antibodies for anti-infective passive immunization and emphasize the need to use relevant in vivo models to evaluate potential therapeutic monoclonal antibodies. Copyright © 2014 Kozel.

  1. Development of OMP based indirect ELISA to gauge the antibody titers in bovines against Pasteurella multocida

    Science.gov (United States)

    Dogra, V; Verma, S; Singh, G; Wani, A. H; Chahota, R; Dhar, P; Verma, L; Sharma, M

    2015-01-01

    Pasteurella multocida (P. multocida) is an important pathogen of various domestic animals. The outer membrane proteins (OMPs) play a major role in pathogenesis and immunogenicity of P. multocida. The aim of the study was to develop indirect enzyme linked immuno sorbant assay (ELISA) based on OMPs to ascertain the antibody titers in animals post-infection or to gauge the potency of vaccine. The OMPs were extracted and purified from P. multocida P:52 (vaccine strain) and P. multocida B:2 isolated from natural outbreak of Haemorrhagic septicaemia (HS) and analyzed on SDS PAGE and through western blot. The OMPs profile of the vaccine strain and the isolate from the natural outbreak of HS were found to be similar. Optimization of various components viz. coating antigens, anti-species conjugate, etc. were carried out against both anti-P. multocida hyper immune and pre immune serum. Validation of OMP based indirect ELISA assay to measure immune response against P. multocida in bovine revealed 91% diagnostic sensitivity (DSN) and about 100% diagnostic specificity (DSP) at 25% cut off. OMP based indirect ELISA was found to be more specific, but less sensitive as compared to WCL based assay. PMID:27175202

  2. Development of a Coxsackievirus A16 neutralization assay based on pseudoviruses for measurement of neutralizing antibody titer in human serum.

    Science.gov (United States)

    Jin, Jun; Ma, Hongxia; Xu, Lin; An, Dong; Sun, Shiyang; Huang, Xueyong; Kong, Wei; Jiang, Chunlai

    2013-02-01

    Serum neutralizing antibody titers are indicative of protective immunity against Coxsackievirus A16 (CV-A16) and Enterovirus 71 (EV71), the two main etiological agents of hand, foot and mouth disease (HFMD), and provide the basis for evaluating vaccine efficacy. The current CV-A16 neutralization assay based on inhibition of cytopathic effects requires manual microscopic examination, which is time-consuming and labor-intensive. In this study, a high-throughput neutralization assay was developed by employing CV-A16 pseudoviruses expressing luciferase for detecting infectivity in rhabdomyosarcoma (RD) cells and measuring serum viral neutralizing antibodies. Without the need to use infectious CV-A16 strains, the neutralizing antibody titer against CV-A16 could be determined within 15h by measuring luciferase signals by this assay. The pseudovirus CV-A16 neutralization assay (pCNA) was validated by comparison with a conventional CV-A16 neutralization assay (cCNA) in testing 174 human serum samples collected from children (age <5 years). The neutralizing antibody titers determined by these two assays were well correlated (R(2)=0.7689). These results suggest that the pCNA can serve as a rapid and objective procedure for the measurement of neutralizing antibodies against CV-A16. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Discovery of human antibodies against black cobra toxins

    DEFF Research Database (Denmark)

    Øhlenschlæger, Mia; Andersen, Mikael Rørdam; Lohse, Brian

    Snakebite envenoming represents a major health threat intropical parts of the developing world1. Animal-derivedantisera currently constitute the only effective treatment option,but are associated with severe side effects due toincompatibility with the human immune system. We aim atdiscovering human...... antibodies that target the medically mostimportant toxins from N. melanoleuca venom using phagedisplay technology....

  4. Comparative evaluation of antibody positive titer by ELISA and IFA in Theileria annulata vaccinated cattle in Iran

    Directory of Open Access Journals (Sweden)

    Hashemi-Fesharki R.

    2006-03-01

    Full Text Available An enzyme linked immunosorbent assay (ELISA was used to evaluate antibody positive titer in vaccinated and non-vaccinated cattle using schizont infected myeloid cells as an antigen. The result was compared with indirect fluorescent antibody level in the same animals. For this study 116 milking cows, 95 vaccinated and 21 non-vaccinated, were bleeded in order to prepare sera. They were tested with both ELISA and IFA tests. 94 sera had positive antibody titer and 22 sera were negative through ELISA test but, with IFA test, only 89 sera showed positive antibody titer and 27 were negative. Thereby, it was concluded that the sensitivity and specificity of ELISA test in comparison with IFA test was 95.5 % and 66.6 % respectively. This study generally indicated that ELISA could be an effective test for seroepidemiological investigations of bovine tropical theileriosis, and it is considered to be valid as an additional test to distinguish the vaccinated from the non vaccinated cattle in order to schedule vaccination programs.

  5. Short report: Changes in West Nile virus seroprevalence and antibody titers among Wisconsin mesopredators 2003-2006

    Science.gov (United States)

    Docherty, D.E.; Samuel, M.D.; Egstad, K.F.; Griffin, K.M.; Nolden, C.A.; Karwal, L.; Ip, Hon S.

    2009-01-01

    After the 2001 occurrence of West Nile virus (WNV) in Wisconsin (WI), we collected sera, during 2003-2006, from south-central WI mesopredators. We tested these sera to determine WNV antibody prevalence and geometric mean antibody titer (GMAT). Four-fold higher antibody prevalence and 2-fold higher GMAT in 2003-2004 indicated greater exposure of mesopredators to WNV during the apparent epizootic phase. The period 2005-2006 was likely the enzootic phase because WNV antibody prevalence fell to a level similar to other flaviviruses. Our results suggest that, in mesopredators, vector-borne transmission is the primary route of infection and WNV antibodies persist for complement dead crow surveillance by providing additional data for the timing of public health interventions. Research is needed to clarify the dynamics of WNV infection in these mammals and their role as potential WNV amplifiers. Copyright ?? 2009 by The American Society of Tropical Medicine and Hygiene.

  6. Decreased vaccine antibody titers following exposure to multiple metals and metalloids in e-waste-exposed preschool children.

    Science.gov (United States)

    Lin, Xinjiang; Xu, Xijin; Zeng, Xiang; Xu, Long; Zeng, Zhijun; Huo, Xia

    2017-01-01

    We explored acquired immunity resulting from vaccination in 3 to 7-year-old children, chronically exposed to multiple heavy metals and metalloids, in an e-waste recycling area (Guiyu, China). Child blood levels of ten heavy metals and metalloids, including lead (Pb), arsenic (As), mercury (Hg), chromium (Cr), cadmium (Cd), manganese (Mn), nickel (Ni), copper (Cu), zinc (Zn) and selenium (Se), and seven vaccine antibodies (diphtheria, pertussis, tetanus, hepatitis B, Japanese encephalitis, polio, measles) were measured. The exposed group had higher levels of blood Pb, Mn, Cu, Zn and Cr compared to the reference group (P vaccine antibodies in the exposed group were significantly lower than in the reference group (P vaccine antibodies negatively correlated with blood concentrations of Cu, Zn and Pb, based on spearman rank correlation analysis. Multiple logistic regression and univariate analyses identified the location of residence (Guiyu), high blood Pb (>10 μg/dL) and high blood Cu and Zn (upper median value of each group) to be inversely associated with seven antibody titers. Antibody titers increased with age, BMI, high blood Mn (>15 μg/L), and high blood Cd and Ni (upper median value of each group). Results suggest multiple heavy metal and metalloid exposure, especially to Pb, Zn and Cu, may be a risk factor inhibiting the development of child immunity, resulting in decreased child antibody levels against vaccines. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Association between antinuclear antibody titers and connective tissue diseases in a Rheumatology Department.

    Science.gov (United States)

    Menor Almagro, Raúl; Rodríguez Gutiérrez, Juan Francisco; Martín-Martínez, María Auxiliadora; Rodríguez Valls, María José; Aranda Valera, Concepción; de la Iglesia Salgado, José Luís

    To determine the dilution titles at antinuclear antibodies (ANA) by indirect immunofluorescence observed in cell substrate HEp-2 and its association with the diagnosis of systemic connective tissue disease in ANA test requested by a Rheumatology Unit. Samples of patients attended for the first time in the rheumatology unit, without prior ANA test, between January 2010 and December 2012 were selected. The dilution titers, immunofluorescence patterns and antigen specificity were recorded. In January 2015 the diagnosis of the patients were evaluated and classified in systemic disease connective tissue (systemic lupus erythematosus, Sjögren's syndrome, systemic sclerosis, undifferentiated connective, antiphospholipid syndrome, mixed connective tissue and inflammatory myophaty) or not systemic disease connective tissue. A total of 1282 ANA tests requested by the Rheumatology Unit in subjects without previous study, 293 were positive, predominance of women (81.9%). Patients with systemic connective tissue disease were recorded 105, and 188 without systemic connective tissue disease. For 1/640 dilutions the positive predictive value in the connective was 73.3% compared to 26.6% of non-connective, and for values ≥1/1,280 85% versus 15% respectively. When performing the multivariate analysis we observed a positive association between 1/320 dilution OR 3.069 (95% CI: 1.237-7.614; P=.016), 1/640 OR 12.570 (95% CI: 3.659-43.187; P=.000) and ≥1/1,280 OR 42.136 (95% CI: 8.604-206.345; P=.000). These results show association titles dilution ≥1/320 in ANA's first test requested by a Rheumatology Unit with patients with systemic connective tissue disease. The VPP in these patients was higher than previous studies requested by other medical specialties. This may indicate the importance of application of the test in a targeted way. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Reumatología y Colegio Mexicano de Reumatología. All rights reserved.

  8. High antibody titer against apical membrane antigen-1 is required to protect against malaria in the Aotus model.

    Directory of Open Access Journals (Sweden)

    Sheetij Dutta

    Full Text Available A Plasmodium falciparum 3D7 strain Apical Membrane Antigen-1 (AMA1 vaccine, formulated with AS02(A adjuvant, slowed parasite growth in a recent Phase 1/2a trial, however sterile protection was not observed. We tested this AS02(A, and a Montanide ISA720 (ISA formulation of 3D7 AMA1 in Aotus monkeys. The 3D7 parasite does not invade Aotus erythrocytes, hence two heterologous strains, FCH/4 and FVO, were used for challenge, FCH/4 AMA1 being more homologous to 3D7 than FVO AMA1. Following three vaccinations, the monkeys were challenged with 50,000 FCH/4 or 10,000 FVO parasites. Three of the six animals in the AMA+ISA group were protected against FCH/4 challenge. One monkey did not become parasitemic, another showed only a short period of low level parasitemia that self-cured, and a third animal showed a delay before exhibiting its parasitemic phase. This is the first protection shown in primates with a recombinant P. falciparum AMA1 without formulation in Freund's complete adjuvant. No animals in the AMA+AS02(A group were protected, but this group exhibited a trend towards reduced growth rate. A second group of monkeys vaccinated with AMA+ISA vaccine was not protected against FVO challenge, suggesting strain-specificity of AMA1-based protection. Protection against FCH/4 strain correlated with the quantity of induced antibodies, as the protected animals were the only ones to have in vitro parasite growth inhibitory activity of >70% at 1:10 serum dilution; immuno-fluorescence titers >8,000; ELISA titers against full-length AMA1 >300,000 and ELISA titer against AMA1 domains1+2 >100,000. A negative correlation between log ELISA titer and day 11 cumulative parasitemia (Spearman rank r = -0.780, p value = 0.0001, further confirmed the relationship between antibody titer and protection. High titers of cross-strain inhibitory antibodies against AMA1 are therefore critical to confer solid protection, and the Aotus model can be used to down-select future AMA1

  9. The Impact of Chemotherapy on Hepatitis B Antibody Titer in Patients with Hematological Malignancies

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    Münci Yağcı

    2015-09-01

    Full Text Available Objective: To investigate the influence of chemotherapy (CT on HBsAb titer in patients receiving CT due to hematological malignancy. Materials and Methods: The data of 75 patients who received CT with the diagnosis of various hematological malignancies and who had serum HBsAb levels measured prior to and after the cessation of CT were evaluated retrospectively. Results: The median age of the patients was 52 years (range: 16-78 with 49 (65% males and 26 (35% females. Median HBsAb titer decreased significantly after CT compared to the pre-CT median HBsAb titer [68 (range: 0-1000 vs. 100 (range: 6.2-1000] (p=0.001. In subgroup analysis, median HBsAb titer decreased significantly after CT in acute leukemia patients [110 (range: 6.2-1000 vs. 67.8 (range: 0-1000] (p=0.003 and in patients receiving intensive CT [97.2 (range: 6.2-1000 vs. 71 (range: 0-1000] (p=0.036. The decrease in median HBsAb titer was significant in male patients (p<0.001. HBsAb became negative after CT in 9 patients who were HBcAb-negative and had lower pre-CT HBsAb levels. Conclusion: HBsAb decreased after CT, especially in acute leukemia and male patients, and in patients receiving intensive CT.

  10. Apolipoprotein E-knockout mice show increased titers of serum anti-nuclear and anti-dsDNA antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yuehai [Cardiovascular Department, Second Clinical Medical College, Fujian Medical University, Quanzhou, Fujian 362000 (China); Huang, Ziyang, E-mail: huangziyang666@126.com [Cardiovascular Department, Second Clinical Medical College, Fujian Medical University, Quanzhou, Fujian 362000 (China); Lu, Huixia [Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Shandong University, Qilu Hospital, Jinan, Shandong 250012 (China); Lin, Huili; Wang, Zhenhua [Cardiovascular Department, Second Clinical Medical College, Fujian Medical University, Quanzhou, Fujian 362000 (China); Chen, Xiaoqing [Department of Rheumatism and Immunology, Second Clinical Medical College, Fujian Medical University, Quanzhou, Fujian 362000 (China); Ouyang, Qiufang [Cardiovascular Department, Second Clinical Medical College, Fujian Medical University, Quanzhou, Fujian 362000 (China); Tang, Mengxiong; Hao, Panpan [Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Shandong University, Qilu Hospital, Jinan, Shandong 250012 (China); Ni, Jingqin [Cardiovascular Department, Second Clinical Medical College, Fujian Medical University, Quanzhou, Fujian 362000 (China); Xu, Dongming [Department of Rheumatism and Immunology, Second Clinical Medical College, Fujian Medical University, Quanzhou, Fujian 362000 (China); Zhang, Mingxiang; Zhang, Qunye [Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education and Chinese Ministry of Health, Shandong University, Qilu Hospital, Jinan, Shandong 250012 (China); Lin, Ling [Department of Rheumatism and Immunology, Second Clinical Medical College, Fujian Medical University, Quanzhou, Fujian 362000 (China); and others

    2012-07-13

    Highlights: Black-Right-Pointing-Pointer Titers of ANA and anti-dsDNA antibodies were higher in ApoE{sup -/-} than C57B6/L mice. Black-Right-Pointing-Pointer Spleen was greater and splenocyte apoptosis lower in ApoE{sup -/-} than B6 mice. Black-Right-Pointing-Pointer Level of TLR4 was lower in spleen tissue of ApoE{sup -/-} than B6 mice. Black-Right-Pointing-Pointer The TLR4 pathway may participate in maintaining the balance of splenocyte apoptosis. Black-Right-Pointing-Pointer The TLR4 pathway may participate in antibody production in spleen tissue. -- Abstract: Apolipoprotein E-knockout (ApoE{sup -/-}) mice, atherosclerosis-prone mice, show an autoimmune response, but the pathogenesis is not fully understood. We investigated the pathogenesis in female and male ApoE{sup -/-} mice. The spleens of all ApoE{sup -/-} and C57BL/6 (B6) mice were weighed. The serum IgG level and titers of anti-nuclear antibody (ANA) and anti-double-stranded DNA (anti-dsDNA) antibody were assayed by ELISA. Apoptosis of spleen tissue was evaluated by TUNEL. TLR4 level in spleen tissue was tested by immunohistochemistry and Western blot analysis. Levels of MyD88, p38, phosphorylated p38 (pp38), interferon regulatory factor 3 (IRF3) and Bcl-2-associated X protein (Bax) in spleen tissue were detected by Western blot analysis. We also survey the changes of serum autoantibodies, spleen weight, splenocyte apoptosis and the expressions of TLR4, MyD88, pp38, IRF3 and Bax in spleen tissue in male ApoE{sup -/-} mice after 4 weeks of lipopolysaccharide (LPS), Toll-like receptor 4 ligand, administration. ApoE{sup -/-} mice showed splenomegaly and significantly increased serum level of IgG and titers of ANA and anti-dsDNA antibody as compared with B6 mice. Splenocyte apoptosis and the expression of TLR4, MyD88, pp38, IRF3 and Bax in spleen tissue were significantly lower in ApoE{sup -/-} than B6 mice. The expression of TLR4, MyD88, IRF3, pp38, and Bax differed by sex in ApoE{sup -/-} spleen tissue. The

  11. Comparison of serum bactericidal and antibody titers induced by two Haemophilus influenzae type b conjugate vaccines: A phase III randomized double-blind study.

    Science.gov (United States)

    Akeda, Yukihiro; Koizumi, Yuka; Takanami, Yohei; Sumino, Shuji; Hattori, Yumi; Sugizaki, Kayoko; Mitsuya, Nodoka; Oishi, Kazunori

    2018-03-14

    Haemophilus influenzae type b (Hib) conjugate vaccines have drastically reduced disease incidence worldwide. Protection against Hib infection has relied on the serum bactericidal activity (SBA) of antibodies to the Hib capsular polysaccharide (polyribosylribitol phosphate). However, licensure usually relies on measuring induction of antibodies to PRP as a surrogate for SBA. In a phase III clinical trial we compared a PRP-conjugate vaccine using the nontoxic diphtheria toxin mutant, CRM 197 , as carrier protein with the licensed tetanus toxoid conjugate when administered subcutaneously as a three dose primary series in Japanese infants. As an addition to the phase III study, we have now evaluated SBA and show PRP-CRM 197 induces higher levels of SBA than PRP-T four weeks after the primary series, with a statistically significant correlation with anti-PRP titers. This data confirms the superior immunogenicity of PRP-CRM 197 compared with PRP-T assessed as SBA following a three-dose primary series by subcutaneous administration. Clinical trial registry: Registered on ClinicalTrials.gov (NCT01379846). Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. Effects of body weight on antibody titers against canine parvovirus type 2, canine distemper virus, and canine adenovirus type 1 in vaccinated domestic adult dogs.

    Science.gov (United States)

    Taguchi, Masayuki; Namikawa, Kazuhiko; Maruo, Takuya; Saito, Miyoko; Lynch, Jonathan; Sahara, Hiroeki

    2012-10-01

    The objective of this study was to determine whether post-vaccination antibody titers vary according to body weight in adult dogs. Antibody titers against canine parvovirus type 2 (CPV-2), canine distemper virus (CDV), and canine adenovirus type 1 (CAdV-1) were measured for 978 domestic adult dogs from 2 to 6 y of age. The dogs had been vaccinated approximately 12 mo earlier with a commercial combination vaccine. The dogs were divided into groups according to their weight. It was found that mean antibody titers in all weight groups were sufficient to prevent infection. Intergroup comparison, however, revealed that CPV-2 antibody titers were significantly higher in the Super Light ( 20 kg) groups and were also significantly higher in the Light (5 to 9.9 kg) group than in the Heavy group. Antibody titers against CDV were significantly higher in the Super Light, Light, and Medium groups than in the Heavy group. There were no significant differences among the groups for the CAdV-1 antibody titers.

  13. Asymmetries in Chickens from Lines Selected and Relaxed for High or Low Antibody Titers to Sheep Red Blood Cells

    Directory of Open Access Journals (Sweden)

    Yunjie Tu

    2015-03-01

    Full Text Available Wattle length, width, and area were measured to classify bilateral asymmetries in four lines of chickens. The lines were the S26 generation of White Leghorns selected for high (HAS or low (LAS response to sheep red blood cells and sublines in which selection had been relaxed for three generations (high antibody relaxed [HAR] and low antibody relaxed [LAR]. Antibody titers (AB were greater for HAS than for HAR with both greater than for LAS and LAR which while different for males did not differ for females. The low antibody lines were heavier and reached sexual maturity at younger age than the high antibody lines. In general, wattle length, width, and area were greater in the low than high antibody lines. In 24 comparisons for bilaterality 18 exhibited fluctuating asymmetry and 6 exhibited directional asymmetry with 5 of the 6 being for wattle length. There was not a clear pattern for changes in degree of asymmetry when selection was relaxed for 3 generations. For females, the relative asymmetry (RA of wattle area was larger (p≤0.05 for HAR than for LAR and not different from the selected lines and relaxed lines. There were no differences among lines for RA of wattle length and width of females and wattle length, width, and area of males.

  14. Prevalence of serum antibody titers against canine distemper virus and canine parvovirus in dogs hospitalized in an intensive care unit.

    Science.gov (United States)

    Mahon, Jennifer L; Rozanski, Elizabeth A; Paul, April L

    2017-06-15

    OBJECTIVE To determine the prevalence of dogs hospitalized in an intensive care unit (ICU) with serum antibody titers against canine distemper virus (CDV) and canine parvovirus (CPV). DESIGN Prospective observational study. ANIMALS 80 dogs. PROCEDURES Dogs hospitalized in an ICU for > 12 hours between February 1 and June 1, 2015, that had at least 0.25 mL of serum left over from diagnostic testing were eligible for study inclusion. Dogs with serum antibody titers > 1:32 (as determined by serum neutralization) and > 1:80 (as determined by hemagglutination inhibition) were considered seropositive for CDV and CPV, respectively. The date of last vaccination was obtained from the medical record of each dog. RESULTS Of the 80 dogs, 40 (50%) and 65 (81%) dogs were seropositive for CDV and CPV, respectively. Of the 40 dogs that were seronegative for CDV, 27 had been vaccinated against CDV within 3 years prior to testing. Of the 15 dogs that were seronegative for CPV, 3 had been vaccinated against CPV within 3 years prior to testing. Ten dogs were seronegative for both CDV and CPV. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated the prevalence of dogs hospitalized in an ICU that were seropositive for CDV and CPV was lower than expected given the high vaccination rate reported for dogs. Although the antibody titer necessary to prevent disease caused by CDV or CPV in critically ill dogs is unknown, adherence to infectious disease control guidelines is warranted when CDV- or CPV-infected dogs are treated in an ICU.

  15. Prevalence of elevated serum anti-N-methyl-D-aspartate receptor antibody titers in patients presenting exclusively with psychiatric symptoms: a comparative follow-up study.

    Science.gov (United States)

    Ando, Yoshihito; Shimazaki, Haruo; Shiota, Katsutoshi; Tetsuka, Syuichi; Nakao, Koichi; Shimada, Tatsuhiro; Kurata, Kazumi; Kuroda, Jinichi; Yamashita, Akihiro; Sato, Hayato; Sato, Mamoru; Eto, Shinkichi; Onishi, Yasunori; Tanaka, Keiko; Kato, Satoshi

    2016-07-08

    Increasing numbers of patients with elevated anti-N-methyl-D-aspartate (NMDA) receptor antibody titers presenting exclusively with psychiatric symptoms have been reported. The aim of the present study was to clarify the prevalence of elevated serum anti-NMDA receptor antibody titers in patients with new-onset or acute exacerbations of psychiatric symptoms. In addition, the present study aimed to investigate the association between elevated anti-NMDA receptor titers and psychiatric symptoms. The present collaborative study included 59 inpatients (23 male, 36 female) presenting with new-onset or exacerbations of schizophrenia-like symptoms at involved institutions from June 2012 to March 2014. Patient information was collected using questionnaires. Anti-NMDA receptor antibody titers were measured using NMDAR NR1 and NR2B co-transfected human embryonic kidney (HEK) 293 cells as an antigen (cell-based assay). Statistical analyses were performed for each questionnaire item. The mean age of participants was 42.0 ± 13.7 years. Six cases had elevated serum anti-NMDA antibody titers (10.2 %), four cases were first onset, and two cases with disease duration >10 years presented with third and fifth recurrences. No statistically significant difference in vital signs or major symptoms was observed between antibody-positive and antibody-negative groups. However, a trend toward an increased frequency of schizophrenia-like symptoms was observed in the antibody-positive group. Serum anti-NMDA receptor antibody titers may be associated with psychiatric conditions. However, an association with specific psychiatric symptoms was not observed in the present study. Further studies are required to validate the utility of serum anti-NMDA receptor antibody titer measurements at the time of symptom onset.

  16. Incidence of serum antibody titers against herpes simplex virus in Japanese patients.

    Science.gov (United States)

    Miyachi, Motoko; Imafuku, Shinichi

    2017-01-01

    Herpes simplex virus (HSV) establishes latency in the sensory neuronal ganglia after primary infection, and occasionally causes recurrent infection, mainly on the lips or genitalia. Previous reports revealed an age-related increase in HSV-immunoglobulin G seropositive subjects in a hospital-based study and the general population in Japan. In this report, we retrospectively analyzed the results of serological tests against HSV, in which subjects were diagnosed with or suspected as having HSV infection. A total of 1216 subjects with at least one complement fixation (CF) result were included. Of these, 771 subjects (63.4%) were positive at first visit. When stratified by age, incidence of positive patients linearly increased with age from teenagers (44.9%) to those in their 80s (88.9%). Positivity in women was higher than in men overall; significantly higher incidence was observed in women aged in their 30s, 40s and 60s. When observing changing HSV-CF titers over time in 81 initially negative patients, 18 (22%) seroconverted during the 2121-day observation period. In this study, we clearly show that distribution of HSV-CF titers is similar to previous HSV-immunoglobulin G results. This correlation is probably caused by the continual subclinical proliferation of HSV, thus maintaining CF titers. Our observations provide current data on the incidence of HSV, reconfirming that serological examination is unreliable in diagnosing recurrent herpes, and the majority of infected subjects are asymptomatic. © 2016 Japanese Dermatological Association.

  17. Effective vitamin B12 treatment can reduce serum antigastric parietal cell antibody titer in patients with oral mucosal disease.

    Science.gov (United States)

    Sun, Andy; Chang, Julia Yu-Fong; Wang, Yi-Ping; Cheng, Shih-Jung; Chen, Hsin-Ming; Chiang, Chun-Pin

    2016-10-01

    Patients with serum antigastric parietal cell antibody (GPCA) positivity may have vitamin B12 deficiency and some oral symptoms. This study assessed the changes of serum GPCA titer in GPCA-positive patients after effective vitamin B12 treatment. Two hundred and ten GPCA-positive oral mucosal disease patients became oral symptom free (complete response) after 1.0-67.1 months of treatment with regular and continuous intramuscular injection of vitamin B12 once per week. The changes of serum GPCA titers after treatment were evaluated in these 210 patients. We found a significant drop of the GPCA positive rate from 100% to 42.9% in our 210 complete response patients after effective vitamin B12 treatment (p vitamin BC capsules (containing 10 μg of vitamin B12) plus deficient hematinic supplements per day after a follow-up period of 2.7-27 months. A maintenance vitamin B12 treatment once a month could retain the GPCA-negative status in 87% of treated-to GPCA-negative patients compared with those (10%) without further maintenance vitamin B12 treatment. Regular and continuous effective vitamin B12 treatment can reduce the relatively higher serum GPCA titers to significantly lower or undetectable levels in GPCA-positive patients. Copyright © 2016. Published by Elsevier B.V.

  18. Australian Aboriginal Children with Otitis Media Have Reduced Antibody Titers to Specific Nontypeable Haemophilus influenzae Vaccine Antigens.

    Science.gov (United States)

    Thornton, Ruth B; Kirkham, Lea-Ann S; Corscadden, Karli J; Wiertsema, Selma P; Fuery, Angela; Jones, B Jan; Coates, Harvey L; Vijayasekaran, Shyan; Zhang, Guicheng; Keil, Anthony; Richmond, Peter C

    2017-04-01

    Indigenous populations experience high rates of otitis media (OM), with increased chronicity and severity, compared to those experienced by their nonindigenous counterparts. Data on immune responses to otopathogenic bacteria in these high-risk populations are lacking. Nontypeable Haemophilus influenzae (NTHi) is the predominant otopathogen in Australia. No vaccines are currently licensed to target NTHi; however, protein D (PD) from NTHi is included as a carrier protein in the 10-valent pneumococcal polysaccharide conjugate vaccine (PHiD10-CV), and other promising protein vaccine candidates exist, including outer membrane protein 4 (P4) and protein 6 (P6). We measured the levels of serum and salivary IgA and IgG against PD, P4, and P6 in Aboriginal and non-Aboriginal children with chronic OM who were undergoing surgery and compared the levels with those in healthy non-Aboriginal children (controls). We found that Aboriginal cases had lower serum IgG titers to all NTHi proteins assessed, particularly PD. In contrast, serum IgA and salivary IgA and IgG titers to each of these 3 proteins were equivalent to or higher than those in both non-Aboriginal cases and healthy controls. While serum antibody levels increased with age in healthy controls, no changes in titers were observed with age in non-Aboriginal cases, and a trend toward decreasing titers with age was observed in Aboriginal cases. This suggests that decreased serum IgG responses to NTHi outer membrane proteins may contribute to the development of chronic and severe OM in Australian Aboriginal children and other indigenous populations. These data are important for understanding the potential benefits of PHiD10-CV implementation and the development of NTHi protein-based vaccines for indigenous populations. Copyright © 2017 Thornton et al.

  19. Australian Aboriginal Children with Otitis Media Have Reduced Antibody Titers to Specific Nontypeable Haemophilus influenzae Vaccine Antigens

    Science.gov (United States)

    Kirkham, Lea-Ann S.; Corscadden, Karli J.; Wiertsema, Selma P.; Fuery, Angela; Jones, B. Jan; Coates, Harvey L.; Vijayasekaran, Shyan; Zhang, Guicheng; Keil, Anthony; Richmond, Peter C.

    2017-01-01

    ABSTRACT Indigenous populations experience high rates of otitis media (OM), with increased chronicity and severity, compared to those experienced by their nonindigenous counterparts. Data on immune responses to otopathogenic bacteria in these high-risk populations are lacking. Nontypeable Haemophilus influenzae (NTHi) is the predominant otopathogen in Australia. No vaccines are currently licensed to target NTHi; however, protein D (PD) from NTHi is included as a carrier protein in the 10-valent pneumococcal polysaccharide conjugate vaccine (PHiD10-CV), and other promising protein vaccine candidates exist, including outer membrane protein 4 (P4) and protein 6 (P6). We measured the levels of serum and salivary IgA and IgG against PD, P4, and P6 in Aboriginal and non-Aboriginal children with chronic OM who were undergoing surgery and compared the levels with those in healthy non-Aboriginal children (controls). We found that Aboriginal cases had lower serum IgG titers to all NTHi proteins assessed, particularly PD. In contrast, serum IgA and salivary IgA and IgG titers to each of these 3 proteins were equivalent to or higher than those in both non-Aboriginal cases and healthy controls. While serum antibody levels increased with age in healthy controls, no changes in titers were observed with age in non-Aboriginal cases, and a trend toward decreasing titers with age was observed in Aboriginal cases. This suggests that decreased serum IgG responses to NTHi outer membrane proteins may contribute to the development of chronic and severe OM in Australian Aboriginal children and other indigenous populations. These data are important for understanding the potential benefits of PHiD10-CV implementation and the development of NTHi protein-based vaccines for indigenous populations. PMID:28151410

  20. Are children's vitamin D levels and BMI associated with antibody titers produced in response to 2014-2015 influenza vaccine?

    Science.gov (United States)

    Lin, Chyongchiou J; Martin, Judith M; Cole, Kelly Stefano; Zimmerman, Richard K; Susick, Michael; Moehling, Krissy K; Levine, Min Z; Spencer, Sarah; Flannery, Brendan; Nowalk, Mary Patricia

    2017-07-03

    Vitamin D is an immunomodulating hormone, which has been associated with susceptibility to infectious diseases. Serum vitamin D levels in 135 children ages 3-17 y were measured at baseline and hemagglutinin influenza antibody titers were measured pre- and 21 d post influenza vaccination with live attenuated influenza vaccine (LAIV) or inactivated influenza vaccine (IIV). Height and weight were derived from the electronic medical record and were used to calculate body mass index (BMI). Thirty-nine percent of children were ages 3-8 years; 75% were black, 34% were obese (BMI ≥ 95 th percentile); vitamin D levels were >20 ng/ml in 55%. In linear regression analyses, post vaccination antibody titers for LAIV B lineages (B Brisbane and B Massachusetts) were significantly higher among those with lower vitamin D levels and among younger participants (P vitamin D levels and responses to LAIV A strains (A/H1N1 and A/H3N2) or to any IIV strains or lineages were found. Low vitamin D levels were associated with higher response to LAIV B lineages in the 2014-2015 LAIV, but not related to LAIV A or any IIV strains.

  1. Component Analysis of Sweet BV and Clinical Trial on Antibody Titer and Allergic Reactions

    Directory of Open Access Journals (Sweden)

    Ki Rok, Kwon

    2006-06-01

    Full Text Available Objectives : The aim of this study was to observe prevention of allergic reactions of Sweet Bee Venom (removing enzyme components from Bee Venom. Methods : Content analysis of Sweet Bee Venom and Bee Venom was rendered using HPLC method and characterization of Anti-Sweet Bee Venom in Rabbit Serum. Clinical observation was conducted for inducement of allergic responses to Sweet BV. Results : 1. Analyzing melittin content using HPLC, Sweet BV contained 34.9% more melittin than Bee venom pharmacopuncture at same concentration. 2. Observing chromatogram of HPLC, removal of the enzyme was successfully rendered on Sweet BV. 3. The anti-serum of Sweet BV showed high titers against melittin and bee venom and relatively low titer against phospholipase A2. 4. After conducting approximately 3,000 cases of Sweet BV administration, not a single case of generalized anaphylatic reaction occurred in clinical observation. 5. Mild compared to the bee venom pharmacopuncture, Sweet BV showed some acute hypersensitive reactions of edema, itchiness, and aching locally. 6. Sweet BV was administered on six patients with previous history of suffering from generalized acute hypersensitive reactions with the bee venom. None of the patients showed allergic reactions with Sweet BV, suggesting it can effectively prevent anaphylatic shock which may occur after the bee venom pharmacopuncture procedure. Conclusion : Summarizing above results, Sweet Bee Venom appears to be an effective measurement against allergic reactions from the bee venom pharmacopuncture especially against anaphylatic shock.

  2. Antibody Titers Following Hepatitis B Vaccination in Health Care Workers in Khartoum State, Sudan

    OpenAIRE

    Eltayib Hassan Ahmad-Abaklur; Amal Obaid; Mohamed Ahmed Abrahim-Holi

    2014-01-01

    Hepatitis B vaccination is the most effective measure to prevent HBV infection and its consequences. The best strategy to eradicate HBV infection is a universal vaccination program. This study was a descriptive cross sectional study aimed at evaluating the efficiency of HBV vaccine in term of anti-HBs Ab level among vaccinated health care workers (HCWs) in Bahri Teaching Hospital, Khartoum state, Sudan. Ninety HCWs agreed to participate in this study, HBV antibody level (quantitative antibody...

  3. [Comparative Study for Anti-Hepatitis B Surface Antigen Titers Based on Two Measurement Methods: Using Monoclonal Antibodies Isolated from Hepatitis B Vaccinated Recipients].

    Science.gov (United States)

    Oone, Kumiko; Kani, Satomi; Oohashi, Minoru; Shinkai, Noboru; Inoue, Takako; Wakimoto, Yukio; Tanaka, Yasuhito

    2015-08-01

    As anti-hepatitis B surface antigen (anti-HBs) titers vary depending on the measurement methods, we compared two different methods to measure anti-HBs titers in sera and HBs monoclonal antibodies. The sera from 182 HB virus-resolved patients who were negative for HBsAg but positive for antiHB core protein (HBc) and/or anti-HBs were obtained. The measurement of anti-HBs was compared using either Lumipulse G1200 or Architect i2000SR. Six different monoclonal antibody (mAbs) clones isolated from healthy individuals inoculated with hepatitis B vaccine Bimmugen (genotype C) were used. A statistically significant correlation in anti-HBs titers was found between the two methods tested (Y = 0.951X + 100.7, R = 0.813, p Lumipulse and 12 (6.6%) were opposite results. Measuring 2 mAbs with HBV neutralizing activity, the titers of the 116 antibody (1.0 μg/mL) were comparable (689.3 mIU/mL by Lumipulse and 440.7 mIU/mL by Architect), whereas those of the 478 antibody (1.0 μg/mL) were much lower by Architect than by Lumipulse (42.6 vs. 818.6 mIU/mL, respectively). Of four other mAbs without HBV neutralizing activity, equal titers were observed for one; two mAbs had less anti-HB titers by Architect; and one was below the cut-off index (Lumipulse, and the potential ability to detect the 478 antibody with neutralizing activity is low, indicating that Architect might underestimate anti-HBs titers. Future studies should standardize the anti-HBs titer measurement system.

  4. Anti-idiotypic antibodies that protect cells against the action of diphtheria toxin

    International Nuclear Information System (INIS)

    Rolf, J.M.; Gaudin, H.M.; Tirrell, S.M.; MacDonald, A.B.; Eidels, L.

    1989-01-01

    An anti-idiotypic serum prepared against the combining site (idiotype) of specific anti-diphtheria toxoid antibodies was characterized with respect to its interaction with highly diphtheria toxin-sensitive Vero cells. Although the anti-idiotypic serum protected Vero cells against the cytotoxic action of diphtheria toxin, it did not prevent the binding of 125 I-labeled diphtheria toxin to the cells but did inhibit the internalization and degradation of 125 I-labeled toxin. This anti-idiotypic serum immunoprecipitated a cell-surface protein from radiolabeled Vero cells with an apparent Mr of approximately 15,000. These results are consistent with the hypothesis that the anti-idiotypic serum contains antibodies that carry an internal image of an internalization site on the toxin and that a cell-surface protein involved in toxin internalization possesses a complementary site recognized by both the toxin and the anti-idiotypic antibodies

  5. Anti-idiotypic antibodies that protect cells against the action of diphtheria toxin

    Energy Technology Data Exchange (ETDEWEB)

    Rolf, J.M.; Gaudin, H.M.; Tirrell, S.M.; MacDonald, A.B.; Eidels, L.

    1989-03-01

    An anti-idiotypic serum prepared against the combining site (idiotype) of specific anti-diphtheria toxoid antibodies was characterized with respect to its interaction with highly diphtheria toxin-sensitive Vero cells. Although the anti-idiotypic serum protected Vero cells against the cytotoxic action of diphtheria toxin, it did not prevent the binding of /sup 125/I-labeled diphtheria toxin to the cells but did inhibit the internalization and degradation of /sup 125/I-labeled toxin. This anti-idiotypic serum immunoprecipitated a cell-surface protein from radiolabeled Vero cells with an apparent Mr of approximately 15,000. These results are consistent with the hypothesis that the anti-idiotypic serum contains antibodies that carry an internal image of an internalization site on the toxin and that a cell-surface protein involved in toxin internalization possesses a complementary site recognized by both the toxin and the anti-idiotypic antibodies.

  6. Comparison of antibody titer against the infectious bursal disease virus following the disease with that obtained from live intermediate vaccines using indirect hemagglutination (IHA test in broiler chicks

    Directory of Open Access Journals (Sweden)

    A Feizi

    2009-02-01

    Full Text Available In this study, antibody titer obtained from the outbreak of the infection bursal disease (IBD was compared with the titer obtained from live intermediate vaccines by indirect haemagglutination (IHA test in broiler chicks. A total of 450 one day old Cobb chicks were divided into 3 groups each containing 150 chicks and were kept for 42 days in the same rearing conditions. Chicks in groups 1 and 2 received Bursin-2 and D-78 vaccines respectively via drinking water n days 14 and 21. The rest of the chicks were kept as the controls (group 4 and did not receive any vaccine against the IBD. Serum samples were collected from all birds 2 weeks after the second IBD vaccination. Additional 150 serum samples were also collected from 3 broiler flocks that were affected by IBD and had a history of vaccination by the previously mentioned method, two weeks after the last clinical sings were observed (group 3. Antibody titer of the samples against the IBD virus were determined by the IHA test and the results were evaluated using ANOVA and SPSS software. The mean antibody titer obtained from Bursin-2 and D-78 vaccines were 3.19 and 3.21 respectively which is less than the titer of 6 needed for protection against the disease. The antibody titer in affected flocks was 7.19. comparison of the mean titer of the two vaccines did not show any significant difference but there was significant difference between the titer obtained from each vaccine and that of the effected flock (p

  7. Veal calves produce less antibodies against C. perfringens alpha toxin compared to beef calves

    OpenAIRE

    Valgaeren, Bonnie; Pardon, Bart; Goossens, Evy; Verherstraeten, Stefanie; Roelandt, Sophie; Timbermont, Leen; Van Der Vekens, Nicky; Stuyvaert, Sabrina; Gille, Linde; Van Driessche, Laura; Haesebrouck, Freddy; Ducatelle, Richard; Van Immerseel, Filip; Deprez, Piet

    2015-01-01

    Enterotoxaemia is a disease with a high associated mortality rate, affecting beef and veal calves worldwide, caused by C. perfringens alpha toxin and perfringolysin. A longitudinal study was conducted to determine the dynamics of antibodies against these toxins in 528 calves on 4 beef and 15 veal farms. The second study aimed to determine the effect of solid feed intake on the production of antibodies against alpha toxin and perfringolysin. The control group only received milk replacer, wher...

  8. Structure of general-population antibody titer distributions to influenza A virus

    NARCIS (Netherlands)

    N.T.D. Nhat (Nguyen Thi Duy); S. Todd (Stephen); E.I. de Bruin (Esther); Thao, T.T.N. (Tran Thi Nhu); Vy, N.H.T. (Nguyen Ha Thao); Quan, T.M. (Tran Minh); Vinh, D.N. (Dao Nguyen); J. van Beek (Janko); Anh, P.H. (Pham Hong); Lam, H.M. (Ha Minh); Hung, N.T. (Nguyen Thanh); Le Thanh, N.T. (Nguyen Thi); Huy, H.L.A. (Huynh Le Anh); Ha, V.T.H. (Vo Thi Hong); Baker, S. (Stephen); Thwaites, G.E. (Guy E.); Lien, N.T.N. (Nguyen Thi Nam); Hong, T.T.K. (Tran Thi Kim); Farrar, J. (Jeremy); C.P. Simmons (Cameron); Chau, N.V.V. (Nguyen Van Vinh); M.P.G. Koopmans D.V.M. (Marion); Boni, M.F. (Maciej F.)

    2017-01-01

    textabstractSeroepidemiological studies aim to understand population-level exposure and immunity to infectious diseases. Their results are normally presented as binary outcomes describing the presence or absence of pathogen-specific antibody, despite the fact that many assays measure continuous

  9. Structure of general-population antibody titer distributions to influenza A virus.

    NARCIS (Netherlands)

    Nhat, Nguyen Thi Duy; Todd, Stacy; de Bruin, Erwin; Thao, Tran Thi Nhu; Vy, Nguyen Ha Thao; Quan, Tran Minh; Vinh, Dao Nguyen; van Beek, Janko; Anh, Pham Hong; Lam, Ha Minh; Hung, Nguyen Thanh; Thanh, Nguyen Thi Le; Huy, Huynh Le Anh; Ha, Vo Thi Hong; Baker, Stephen; Thwaites, Guy E; Lien, Nguyen Thi Nam; Hong, Tran Thi Kim; Farrar, Jeremy; Simmons, Cameron P; Chau, Nguyen Van Vinh; Koopmans, Marion; Boni, Maciej F

    2017-01-01

    Seroepidemiological studies aim to understand population-level exposure and immunity to infectious diseases. Their results are normally presented as binary outcomes describing the presence or absence of pathogen-specific antibody, despite the fact that many assays measure continuous quantities. A

  10. High Titers of Mucosal and Systemic anti-PrP Antibodies Abrogates Oral Prion Infection in Mucosal Vaccinated Mice

    Science.gov (United States)

    Goñi, Fernando; Chabalgoity, Jose A.; Prelli, Frances; Schreiber, Fernanda; Scholtzova, Henrieta; Chung, Erika; Kascsak, Richard; Kascsak, Regina; Brown, David R.; Sigurdsson, Einar M.; Wisniewski, Thomas

    2008-01-01

    Significant outbreaks of prion disease linked to oral exposure of the prion agent have occurred in animal and human populations. These disorders are associated with a conformational change of a normal protein, PrPC, to a toxic and infectious form, PrPSc. None of the prionoses currently have an effective treatment. Some forms of prion disease are thought to be spread by oral ingestion of PrPSc, such as chronic wasting disease and variant Creutzfeldt-Jakob disease. Attempts to obtain an active immunization in wild-type animals have been hampered by auto-tolerance to PrP and potential toxicity. Previously, we demonstrated that it is possible to overcome tolerance and obtain a specific anti-PrP antibody response by oral inoculation of the PrP protein expressed in an attenuated Salmonella vector. This past study showed that 30% of vaccinated animals were free of disease more than 350 days post-challenge. In the current study we have both optimized the vaccination protocol and divided the vaccinated mice into low and high immune responder groups prior to oral challenge with PrPSc scrapie strain 139A. These methodological refinements lead to a significantly improved therapeutic response. 100% of mice with a high mucosal anti-PrP titer IgA and a high systemic IgG titer, prior to challenge, remained without symptoms of PrP infection at 400 days (long-rank test poral route PMID:18407424

  11. Structural basis for immunization with postfusion respiratory syncytial virus fusion F glycoprotein (RSV F) to elicit high neutralizing antibody titers

    Energy Technology Data Exchange (ETDEWEB)

    Swanson, Kurt A.; Settembre, Ethan C.; Shaw, Christine A.; Dey, Antu K.; Rappuoli, Rino; Mandl, Christian W.; Dormitzer, Philip R.; Carfi, Andrea (Novartis)

    2012-02-07

    Respiratory syncytial virus (RSV), the main cause of infant bronchiolitis, remains a major unmet vaccine need despite more than 40 years of vaccine research. Vaccine candidates based on a chief RSV neutralization antigen, the fusion (F) glycoprotein, have foundered due to problems with stability, purity, reproducibility, and potency. Crystal structures of related parainfluenza F glycoproteins have revealed a large conformational change between the prefusion and postfusion states, suggesting that postfusion F antigens might not efficiently elicit neutralizing antibodies. We have generated a homogeneous, stable, and reproducible postfusion RSV F immunogen that elicits high titers of neutralizing antibodies in immunized animals. The 3.2-{angstrom} X-ray crystal structure of this substantially complete RSV F reveals important differences from homology-based structural models. Specifically, the RSV F crystal structure demonstrates the exposure of key neutralizing antibody binding sites on the surface of the postfusion RSV F trimer. This unanticipated structural feature explains the engineered RSV F antigen's efficiency as an immunogen. This work illustrates how structural-based antigen design can guide the rational optimization of candidate vaccine antigens.

  12. Low Titers of Canine Distemper Virus Antibody in Wild Fishers (Martes pennanti) in the Eastern USA.

    Science.gov (United States)

    Peper, Steven T; Peper, Randall L; Mitcheltree, Denise H; Kollias, George V; Brooks, Robert P; Stevens, Sadie S; Serfass, Thomas L

    2016-01-01

    Canine distemper virus (CDV) infects species in the order Carnivora. Members of the family Mustelidae are among the species most susceptible to CDV and have a high mortality rate after infection. Assessing an animal's pathogen or disease load prior to any reintroduction project is important to help protect the animal being reintroduced, as well as the wildlife and livestock in the area of relocation. We screened 58 fishers for CDV antibody prior to their release into Pennsylvania, US, as part of a reintroduction program. Five of the 58 (9%) fishers had a weak-positive reaction for CDV antibody at a dilution of 1:16. None of the fishers exhibited any clinical sign of canine distemper while being held prior to release.

  13. Low titers of measles antibody in mothers whose infants suffered from measles before eligible age for measles vaccination

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    Wu Qiaozhen

    2010-05-01

    Full Text Available Abstract Background Resurgence or outbreak of measles recently occurred in both developed and developing countries despite long-standing widespread use of measles vaccine. Measles incidence in China has increased since 2002, particularly in infants and in persons ≥ 15 years of age. It is speculated that infants may acquire fewer measles IgG from their mothers, resulting in the reduced duration of protection during their early months of life. This study aimed to clarify the reason of increased susceptibility to measles in young infants in China. Measles IgG in 24 measles infants ≤ 9 months of age and their vaccinated mothers was quantitatively measured. The mean measles neutralizing titer in the vaccinated mothers and in 13 age-match women with the histories of clinical measles were compared. Results All the mothers were confirmed to be vaccinated successfully by the presence of measles IgG. Six vaccinated mothers were positive for measles IgM and had high concentrations of measles IgG and the neutralizing antibody, indicating underwent natural boosting. The mean measles neutralizing titer in 18 vaccinated mothers without natural boosting were significantly lower than that in 13 age-match women with the histories of clinical measles (1:37 vs 1:182, P Conclusions Our results suggest that infants born to mothers who acquired immunity to measles by vaccination may get a relatively small amount of measles antibody, resulting in loss of the immunity to measles before the vaccination age. Measures to improve the immunity in young infants not eligible for measles vaccination would be critical to interrupt the measles transmission in China.

  14. Neospora caninum in Wild Waterfowl: Occurrence of Parasite DNA and Low Antibody Titers.

    Science.gov (United States)

    Rocchigiani, G; Poli, A; Nardoni, S; Papini, R; Mancianti, F

    2017-02-01

    Thirty-five adult waterfowl (14 males and 21 females) representing various orders and species were sampled during the hunting season from 2015 to 2016. Antibodies to Neospora caninum were detected by IFAT on blood samples, while heart and brain were subjected to molecular analysis for the detection of Neospora caninum DNA. Twelve birds (34.3%) (6 Anas crecca , 3 Anas platyrhynchos , 2 Anas penelope , 1 Anas acuta ) showed antibodies versus N. caninum , while 10 animals out of 35 (4 A. crecca , 2 A. platyrhynchos , 2 A. penelope , 1 A. acuta , and 1 Vanellus vanellus ) scored positive for at least 1 DNA sample, with an overall prevalence of 28.6%. The present report shows for the first time the occurrence of antibodies and N. caninum DNA in waterfowl. The avian species investigated in the present report, which feed directly from the soil and/or water, would be able to ingest oocysts excreted by final canid hosts and could contribute to parasite transmission in the sylvatic cycle. To achieve a definitive result about the role of these avian species in the epidemiology of this protozoan, the presence of viable parasites should be demonstrated by bioassay and/or culture, as well as histological evidence of N. caninum cysts in avian tissues.

  15. Detection of antibody responses by using haemagglutination inhibiton test and the protection titer of avian influenza virus H5N1 subtype

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    Risa Indriani

    2004-10-01

    Full Text Available Study on the detection of antibody responses using haemagglutination inhibition (HI test and the protection titer to Avian influenza (AI virus H5N1 subtype local isolate has been conducted at the Research Institute for Veterinary Science (RIVS. A total number of 50 village chicken (10 chicken served as un-injected controls and 30 quail were injected intramuscularly with inactivated virus of AI H5N1 subtype local isolate. Serum samples were collected 3 weeks after injection and were tested using haemagglutination inhibition tests. The correlation between antibody titer and its protection to AI virus H5N1 local isolate were measured by challenging the birds with AI virus H5N1 local isolate The HI test was then used to determine field serum samples. A total number of 48 village chicken from three (3 Districts (Bekasi, Tangerang and Bogor and 96 quails from two (2 farms in District of Sukabumi which were all vaccinated with commercial AI adjuvant vaccine were sampled. The study revealed that village chicken and quails showed antibody responses after 3 weeks vaccination and that titer of ≥ 3 log 2 was able to protect chicken and quails when they were challenged with local isolate virus. Based on this result, village chicken field samples from Districts of Tangerang, Bekasi and Bogor showed antibody titer which will protect 50, 100 and 85% of the flocks respectively. While quail field samples from Farm I and Farm II in District of Sukabumi showed antibody titer which will protect 60-100% and 0-80% of the flocks respectively. It is concluded that the study has successfully measured antibody titer to AI virus H5N1 subtype which protect village chicken and quails from local isolate virus challenge so that the results will be used to analyze field serum samples after vaccination program to eradicate AI from Indonesia.

  16. SINGLE CHAIN VARIABLE FRAGMENTS OF ANTIBODIES AGAINST DIPHTHERIA TOXIN B-SUBUNIT ISOLATED FROM PHAGE DISPLAY HUMAN ANTIBODY LIBRARY

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    Oliinyk O. S.

    2014-02-01

    Full Text Available Diphtheria toxin is an exoantigen of Corynebacterium diphtheriae that inhibits protein synthesis and kills sensitive cells. The aim of this study was to obtain human recombinant single-chain variable fragment (scFv antibodies against receptor-binding B subunit of diphtheria toxin. 12 specific clones were selected after three rounds of a phage display naїve (unimmunized human antibody library against recombinant B-subunit. scFv DNA inserts from these 12 clones were digested with MvaI, and 6 unique restriction patterns were found. Single-chain antibodies were expressed in Escherichia coli XL1-blue. The recombinant proteins were characterized by immunoblotting of bacterial extracts and detection with an anti-E-tag antibody. The toxin B-subunit-binding function of the single-chain antibody was shown by ELISA. The affinity constants for different clones were found to be from 106 to 108 М–1. Due to the fact, that these antibody fragments recognized epitopes in the receptor-binding Bsubunit of diphtheria toxin, further studies are interesting to evaluate their toxin neutralization properties and potential for therapeutic applications. Obtained scFv-antibodies can also be used for detection and investigation of biological properties of diphtheria toxin.

  17. HIV-1 specific antibody titers and neutralization among chronically infected patients on long-term suppressive antiretroviral therapy (ART: a cross-sectional study.

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    Johannes S Gach

    Full Text Available The majority of potent and broadly neutralizing antibodies against HIV-1 have been isolated from untreated patients with acute or chronic infection. To assess the extent of HIV-1 specific antibody response and neutralization after many years of virologic suppression from potent combination ART, we examined antibody binding titers and neutralization of 51 patients with chronic HIV-1 infection on suppressive ART for at least three years. In this cross-sectional analysis, we found high antibody titers against gp120, gp41, and the membrane proximal external region (MPER in 59%, 43%, and 27% of patients, respectively. We observed significantly higher endpoint binding titers for gp120 and gp41 for patients with >10 compared to ≤ 10 years of detectable HIV RNA. Additionally, we observed higher median gp120 and gp41 antibody titers in patients with HIV RNA 10 years of detectable HIV RNA (8/20 [40.0%] versus 3/31 [9.7%] for ≤ 10 years, p = 0.02 and a trend toward greater neutralization in patients with ≤ 5 years of HIV RNA 5 years, p = 0.08. All patients with neutralizing activity mediated successful phagocytosis of VLPs by THP-1 cells after antibody opsonization. Our findings of highly specific antibodies to several structural epitopes of HIV-1 with antibody effector functions and neutralizing activity after long-term suppressive ART, suggest continuous antigenic stimulation and evolution of HIV-specific antibody response occurs before and after suppression with ART. These patients, particularly those with slower HIV progression and more time with detectable viremia prior to initiation of suppressive ART, are a promising population to identify and further study functional antibodies against HIV-1.

  18. A systematic review of anti-rotavirus serum IgA antibody titer as a potential correlate of rotavirus vaccine efficacy.

    Science.gov (United States)

    Patel, Manish; Glass, Roger I; Jiang, Baoming; Santosham, Mathuram; Lopman, Ben; Parashar, Umesh

    2013-07-15

    Identifying an immunological correlate of protection for rotavirus vaccines (Rotarix [RV1] and RotaTeq [RV5]) would substantially facilitate testing of interventions for improving efficacy in developing countries and evaluating additional candidate rotavirus vaccines. We accessed PubMed and ClinicalTrials.gov to identify immunogenicity and efficacy trials for RV1 and RV5 to correlate anti-rotavirus serum immunoglobulin A (IgA) antibody titers vs efficacy in regions stratified by all-cause under-5 mortality rates (u5MR). We established a cutoff point for IgA geometric mean concentration or titer (GMC) that predicted lower efficacy and calculated pooled vaccine efficacy among countries with high vs low IgA titers. We observed an inverse correlation between u5MR and IgA titers for RV1 (r(2) = 0.72; P rotavirus IgA GMC 90 (85%; 95% CI, 82-88). We observed a significant correlation between IgA titers and rotavirus vaccine efficacy and hypothesize that a critical level of IgA antibody titer is associated with a sufficient level of sustained protection after rotavirus vaccination.

  19. Study on Anti-Hepatitis B Surface Antibody Titer and Specific Interferon Gamma Response Among Dentists

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    Manoochehr Makvandi

    2017-01-01

    Full Text Available Background Hepatitis B virus (HBV is a major problem for healthcare workers worldwide, and among them, dentists are at risk of acquiring HBV infection. The prevalence of HBV infection has been reported among the dentists in different regions of the world. Since none of the available drugs can clear HBV infection, the presence of effective immunity against HBV infection is important to prevent HBV infection. Objectives This study aimed at determining HBs antibody and specific HBV gamma interferon among the dentists, who received hepatitis B vaccine. Methods The blood samples were collected from 40 dentists, including 7 endodontics, 2 oral and maxillofacial radiologist, 4 periodontics, 11 oral and maxillofacial surgeons, 6 implantologists, 3 orthodontics, 1 oral and maxillofacial pathologist, 2 esthetic and restorative dentists, and 4 doctors of dental surgery (DDS at from dental college of Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran during December, 2013. Overall, 31 (77.5% dentists had already received 3 doses of recombinant hepatitis B vaccine, and 9 (22.5% had received only two doses of the vaccine. Their sera were tested for HBsAb and anti-HBc-IgG by the Enzyme Linked Immunosorbent Assay (ELISA test. The lymphocyte of individuals was separated from their blood sample by Ficoll-Hypaque, cells were washed with phosphate buffered saline (PBS by centrifugation, and finally the pellet cells was resuspended in RPMI-1640 media. Separated cells were exposed to 2.5 µg of purified recombinant HBs antigen, and supernatants were collected after 72 hours and tested for detection of specific interferon γ level by ELISA test. Results Overall, 97.5% of dentists showed positive HBs antibody test results while 36 showed (90% positive test results for specific interferon γ against hepatitis B virus infection. Conclusions High coverage of 97.5% immune response against hepatitis B infection was found, indicating high efficacy of recombinant

  20. Short duration of neutralizing antibody titers after pre-exposure rabies vaccination with suckling mouse brain vaccine

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    Zanetti C.R.

    1998-01-01

    Full Text Available The human anti-rabies pre-exposure treatment currently used in Brazil, employing a 1-ml dose of suckling mouse brain vaccine (SMBV administered on days 0, 2, 4 and 28, was compared to an alternative treatment with two 1 ml-doses on day 0, and one 1 ml-dose injected on days 7 and 21. The latter induced higher virus-neutralizing antibody (VNA titers on day 21. Both Brazilian rabies vaccines produced with PV or CVS rabies virus strains were tested. Two additional volunteer vaccinee groups, receiving the pre-exposure and the abbreviated post-exposure schedules recommended by the WHO using cell-culture vaccine (CCV produced with PM rabies virus strain, were included as reference. The VNA were measured against both PV and CVS strains on days 21, 42 and 180 by the cell-culture neutralization microtest. The PV-SMBV elicited higher seroconversion rates and VNA by day 21 than the CVS-SMBV. Both, however, failed to induce a long-term immunity, since VNA titers were <0.5 IU/ml on day 180, regardless of the schedule used. Cell-culture vaccine always elicited very high VNA on all days of collection. When serum samples from people receiving mouse brain tissue were titrated against the PV and CVS strains, the VNA obtained were similar, regardless of the vaccinal strain and the virus used in the neutralization test. These results contrast with those obtained with sera from people receiving PM-CCV, whose VNA were significantly higher when tested against the CVS strain.

  1. Mimotopes selected by biopanning with high-titer HIV-neutralizing antibodies in plasma from Chinese slow progressors

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    Xiaoli Zhang

    Full Text Available OBJECTIVE: One approach to identifying HIV-1 vaccine candidates is to dissect the natural antiviral immune response in treatment-naïve individuals infected for over ten years, considered slow progressor patients (SPs. It is suspected that SP plasma has strongly neutralizing antibodies (NAb targeting specific HIV viral epitopes. METHODS: NAbs levels of 11 HIV-1-infected SPs were detected by PBMC-based neutralization assays. To investigate SP NAb epitope, this study used a biopanning approach to obtain mimotopes of HIV-1 that were recognized by SP plasma NAbs. IgG was purified from hightiter NAb SP plasma, and used as the ligand for three rounds of biopanning to select HIV-specific mimotopes from a phage-displayed random peptide library. Double-antibody sandwich ELISA, competitive inhibition assays, and peptide sequence analysis were used to evaluate the characteristics of phage-borne mimotopes. RESULTS: SPs had significantly more plasma neutralizing activity than typical progressors (TPs (p = 0.04. P2 and P9 plasma, which have highest-titer HIV-NAb, were selected as ligands for biopanning. After three rounds of biopanning, 48 phage clones were obtained, of which 22 clones were consistent with requirement, binding with HIV-1 positive plasma and unbinding with HIV-1 negative plasma. Compared with linear HIV-1 protein sequence and HIV-1 protein structure files, only 12 clones were possible linear mimotopes of NAbs. In addition, the C40 clone located in gp41 CHR was found to be a neutralizing epitope, which could inhibit pooled HIV-1 positive plasma reaction. CONCLUSION: Biopanning of serum IgG can yield mimotopes of HIV-1-related antigen epitopes. This methodology provides a basis for exploration into HIV-1-related antigen-antibody interactions and furthers NAb immunotherapy and vaccine design.

  2. Successful reduction of high-sustained anti-idursulfase antibody titers by immune modulation therapy in a patient with severe mucopolysaccharidosis type II

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    Katherine H. Kim

    2015-03-01

    Full Text Available We report on a 6 year old boy with severe MPS II undergoing immune modulation therapy due to high IgG antibody titers to IV idursulfase and no significant decline in urinary GAG levels since initiating enzyme replacement therapy. He has complete deficiency of iduronate-2-sulfatase activity due to a submicroscopic deletion of the X chromosome involving the entire I2S gene but not including in the fragile X locus. At 19 months of age, IV idursulfase therapy at the recommended dose of 0.5 mg/kg/week was initiated and then increased to 1.0 mg/kg/week after no observed clinical improvement and no decline in urine GAG level. After one year of ERT at the increased dose, he had no significant decline in urinary GAG excretion and increase of anti-idursulfase IgG antibody titers to 102,000 with complete neutralizing antibodies. In light of the evidence of lack of efficacy of idursulfase therapy, the patient was started on an immune modulation regimen consisting of ofatumumab, bortezomib, methotrexate and IVIG for a 12 week period. Only a slight decrease in IgG titers and urine GAG levels was observed, leading to increased intensity of bortezomib administration and addition of dexamethasone to the regimen, while continuing with the current schedule ofatumumab, IVIG and methotrexate. Over 18 month period of immune modulation therapy, we observed a significant reduction in anti-idursulfase IgG titers and a moderate reduction in urine GAG levels compared to baseline. Modest clinical improvements were observed. Our experience suggests that future MPS II patients with a complete gene deletion may be likely to develop persistent anti-idursulfase antibody titers and may benefit from immune modulation therapy prior to the development of high titer levels.

  3. The importance of tumor marker titers for the indication of immunoscintigraphy with monoclonal antibodies anti-CEA and anti-CA 19.9

    International Nuclear Information System (INIS)

    Bouvier, J.F.; Charrie, A.; Fleury-Goyon, M.C.; Chauvot, P. et; Lahneche, B.E.

    1986-01-01

    In 18 patients operated for malignant tumors 20 immunoscintigraphies were done with a monoclonal antibody cocktail (anti-CEA F(ab') 2 and anti-CA 19.9 F(ab') 2 ). Immediately before scintigraphy tumor marker titers in plasma were determined in all cases. Tumor marker levels corresponding to positive or doubtful scintigraphies are analysed. (Author)

  4. Veal Calves Produce Less Antibodies against C. Perfringens Alpha Toxin Compared to Beef Calves

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    Bonnie R. Valgaeren

    2015-07-01

    Full Text Available Enterotoxaemia is a disease with a high associated mortality rate, affecting beef and veal calves worldwide, caused by C. perfringens alpha toxin and perfringolysin. A longitudinal study was conducted to determine the dynamics of antibodies against these toxins in 528 calves on 4 beef and 15 veal farms. The second study aimed to determine the effect of solid feed intake on the production of antibodies against alpha toxin and perfringolysin. The control group only received milk replacer, whereas in the test group solid feed was provided. Maternal antibodies for alpha toxin were present in 45% of the veal calves and 66% of the beef calves. In beef calves a fluent transition from maternal to active immunity was observed for alpha toxin, whereas almost no veal calves developed active immunity. Perfringolysin antibodies significantly declined both in veal and beef calves. In the second study all calves were seropositive for alpha toxin throughout the experiment and solid feed intake did not alter the dynamics of alpha and perfringolysin antibodies. In conclusion, the present study showed that veal calves on a traditional milk replacer diet had significantly lower alpha toxin antibodies compared to beef calves in the risk period for enterotoxaemia, whereas no differences were noticed for perfringolysin.

  5. Veal Calves Produce Less Antibodies against C. Perfringens Alpha Toxin Compared to Beef Calves

    Science.gov (United States)

    Valgaeren, Bonnie R.; Pardon, Bart; Goossens, Evy; Verherstraeten, Stefanie; Roelandt, Sophie; Timbermont, Leen; Van Der Vekens, Nicky; Stuyvaert, Sabrina; Gille, Linde; Van Driessche, Laura; Haesebrouck, Freddy; Ducatelle, Richard; Van Immerseel, Filip; Deprez, Piet

    2015-01-01

    Enterotoxaemia is a disease with a high associated mortality rate, affecting beef and veal calves worldwide, caused by C. perfringens alpha toxin and perfringolysin. A longitudinal study was conducted to determine the dynamics of antibodies against these toxins in 528 calves on 4 beef and 15 veal farms. The second study aimed to determine the effect of solid feed intake on the production of antibodies against alpha toxin and perfringolysin. The control group only received milk replacer, whereas in the test group solid feed was provided. Maternal antibodies for alpha toxin were present in 45% of the veal calves and 66% of the beef calves. In beef calves a fluent transition from maternal to active immunity was observed for alpha toxin, whereas almost no veal calves developed active immunity. Perfringolysin antibodies significantly declined both in veal and beef calves. In the second study all calves were seropositive for alpha toxin throughout the experiment and solid feed intake did not alter the dynamics of alpha and perfringolysin antibodies. In conclusion, the present study showed that veal calves on a traditional milk replacer diet had significantly lower alpha toxin antibodies compared to beef calves in the risk period for enterotoxaemia, whereas no differences were noticed for perfringolysin. PMID:26184311

  6. A Monoclonal Antibody Based Capture ELISA for Botulinum Neurotoxin Serotype B: Toxin Detection in Food

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    Larry H. Stanker

    2013-11-01

    Full Text Available Botulism is a serious foodborne neuroparalytic disease, caused by botulinum neurotoxin (BoNT, produced by the anaerobic bacterium Clostridium botulinum. Seven toxin serotypes (A–H have been described. The majority of human cases of botulism are caused by serotypes A and B followed by E and F. We report here a group of serotype B specific monoclonal antibodies (mAbs capable of binding toxin under physiological conditions. Thus, they serve as capture antibodies for a sandwich (capture ELISA. The antibodies were generated using recombinant peptide fragments corresponding to the receptor-binding domain of the toxin heavy chain as immunogen. Their binding properties suggest that they bind a complex epitope with dissociation constants (KD’s for individual antibodies ranging from 10 to 48 × 10−11 M. Assay performance for all possible combinations of capture-detector antibody pairs was evaluated and the antibody pair resulting in the lowest level of detection (L.O.D., ~20 pg/mL was determined. Toxin was detected in spiked dairy samples with good recoveries at concentrations as low as 0.5 pg/mL and in ground beef samples at levels as low as 2 ng/g. Thus, the sandwich ELISA described here uses mAb for both the capture and detector antibodies (binding different epitopes on the toxin molecule and readily detects toxin in those food samples tested.

  7. CORRELATION OF PEMPHIGUS VULGARIS ANTIBODY TITERS BY INDIRECT IMMUNOFLUORESCENCE WITH ACTIVITY OF DISEASE BASED ON PEMPHIGUS AREA AND ACTIVITY SCORE (PAAS

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    H. Mortazavi

    2008-06-01

    Full Text Available Indirect immunofluorescence (IIF has been used to identify and measure autoantibody levels in pemphigus vulgaris but data about relationship between clinical severity of disease and antibody titers by IIF have been conflicting. We conducted this cross-sectional study to correlate the severity of oral and/or cutaneous involvement in patients with pemphigus vulgaris based on Pemphigus Area and Activity Score with IIF titers. Sixty-one new pemphigus vulgaris patients were included in this study. Human prepuce was used as substrate for IIF and assessment of disease severity was based on Pemphigus Area and Activity Score. The mean±SD age was 44.04±30.46 years, with a range of 18 to 79 years. IIF was positive in 56 (91.8% patients. There was a significant relationship between total disease score and IIF titers ((P<0.001. Also a significant relationship was found between skin score (P=0.04 and mucosal score (P=0.04 with IIF titers. Our results show that there is a significant relationship between disease activity based on Pemphigus Area and Activity Score and antibody titers by IIF. Further studies are recommended to determine the usefulness of this technique for monitoring disease.

  8. Detection of ALMB-toxin in the larval body of Myrmeleon bore by anti-N-terminus peptide antibodies.

    Science.gov (United States)

    Yoshida, N; Sugama, H; Gotoh, S; Matsuda, K; Nishimura, K; Komai, K

    1999-01-01

    Antibodies were raised against a synthetic antigen carrying the N-terminus peptide of ALMB-toxin, which had been isolated from the antlion, Myrmeleon bore, that exhibited high specificity to the toxin. Analyses with the antibodies showed the toxin to be present mainly at the larval stage and localized in a region from the thorax to abdomen of the larval body.

  9. Transcutaneous immunization with cross-reacting material CRM(197) of diphtheria toxin boosts functional antibody levels in mice primed parenterally with adsorbed diphtheria toxoid vaccine.

    Science.gov (United States)

    Stickings, Paul; Peyre, Marisa; Coombes, Laura; Muller, Sylviane; Rappuoli, Rino; Del Giudice, Giuseppe; Partidos, Charalambos D; Sesardic, Dorothea

    2008-04-01

    Transcutaneous immunization (TCI) capitalizes on the accessibility and immunocompetence of the skin, elicits protective immunity, simplifies vaccine delivery, and may be particularly advantageous when frequent boosting is required. In this study we examined the potential of TCI to boost preexisting immune responses to diphtheria in mice. The cross-reacting material (CRM(197)) of diphtheria toxin was used as the boosting antigen and was administered alone or together with either one of two commonly used mucosal adjuvants, cholera toxin (CT) and a partially detoxified mutant of heat-labile enterotoxin of Escherichia coli (LTR72). We report that TCI with CRM(197) significantly boosted preexisting immune responses elicited after parenteral priming with aluminum hydroxide-adsorbed diphtheria toxoid (DTxd) vaccine. In the presence of LTR72 as an adjuvant, toxin-neutralizing antibody titers were significantly higher than those elicited by CRM(197) alone and were comparable to the functional antibody levels induced after parenteral booster immunization with the adsorbed DTxd vaccine. Time course study showed that high levels of toxin-neutralizing antibodies persisted for at least 14 weeks after the transcutaneous boost. In addition, TCI resulted in a vigorous antigen-specific proliferative response in all groups of mice boosted with the CRM(197) protein. These findings highlight the promising prospect of using booster administrations of CRM(197) via the transcutaneous route to establish good herd immunity against diphtheria.

  10. High prevalence of subclass-specific binding and neutralizing antibodies against Clostridium difficile toxins in adult cystic fibrosis sera: possible mode of immunoprotection against symptomatic C. difficile infection

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    Monaghan TM

    2017-07-01

    patients with symptomatic C. difficile infection (n=16; p≤0.05. The same pattern of response prevailed for IgG, except that there was no difference in anti-toxin A IgG levels between the groups. Compared with healthy controls (toxins A and B and patients with C. difficile infection (toxin A, sera from cystic fibrosis patients exhibited significantly stronger protective anti-toxin neutralizing antibody responses.Conclusion: A superior ability to generate robust humoral immunity to C. difficile toxins in the cystic fibrosis population is likely to confer protection against symptomatic C. difficile infection. This protection may be lost in the post-transplantation setting, where sera monitoring of anti-C. difficile toxin antibody titers may be of clinical value. Keywords: Clostridium difficile, cystic fibrosis, antibodies  

  11. Lack of correlation between serum rotavirus antibody titers and protection following vaccination with reassortant RRV vaccines. US Rotavirus Vaccine Efficacy Group.

    Science.gov (United States)

    Ward, R L; Bernstein, D I

    1995-09-01

    In a large placebo-controlled efficacy trial of the rhesus tetravalent (RRV-TV) and serotype 1 monovalent (RRV-S1) rotavirus vaccines in multiple sites throughout the United States, protection against rotavirus disease over a 2-year period was found to be 57 and 40%, respectively (Bernstein et al., J. Am. Med. Assoc., 1995, 273, 1191-1196). Sera collected from a subset of subjects during this trial were used to determine possible correlations between rotavirus antibody responses after vaccination and protection. Between 82% (RRV-S1) and 92% (RRV-TV) of the vaccinees seroconverted by at least one of the six antibody assays performed (i.e. rotavirus IgA and neutralizing antibody to RRV and serotype 1-4 human rotaviruses). Rises in neutralizing antibody were due primarily to RRV. The seroconversion rate was only 18-22% to each of the four human rotavirus serotypes following RRV-TV vaccination and was only 43% to serotype 1 human rotavirus after RRV-S1 administration. Furthermore, no correlate of immunity against rotavirus infection or disease was identifiable based on seroconversion to any of the antibodies measured. Likewise, no consistent relationship was found between the titers of any of these six antibodies following vaccination and protection against rotavirus, thus suggesting that serum antibody titers will not be useful markers of protection with these reassortant RRV vaccines. In addition, vaccinated subjects did not develop higher titers of neutralizing antibody to human rotaviruses following a subsequent natural rotavirus illness, a further indication that only weak immune responses to human rotaviruses were stimulated by vaccination with the RRV reassortants.(ABSTRACT TRUNCATED AT 250 WORDS)

  12. High Titers of IgE Antibody to Dust Mite Allergen and the Risk for Wheezing Among Asthmatic Children Infected with Rhinovirus

    Science.gov (United States)

    Soto-Quiros, Manuel; Avila, Lydiana; Platts-Mills, Thomas AE; Hunt, John F.; Erdman, Dean D.; Carper, Holliday; Murphy, Deborah D.; Odio, Silvia; James, Hayley R.; Patrie, James T.; Hunt, William; O’Rourke, Ashli K.; Davis, Michael D.; Steinke, John W.; Lu, Xiaoyan; Kennedy, Joshua; Heymann, Peter W.

    2013-01-01

    Background The relevance of allergic sensitization, judged by titers of serum IgE antibodies, to the risk of an asthma exacerbation caused by rhinovirus is unclear. Objective To examine the prevalence of rhinovirus infections in relation to the atopic status of children treated for wheezing in Costa Rica, a country with an increased asthma burden. Methods The children enrolled (n=287) were 7 through 12 years old. They included 96 with acute wheezing, 65 with stable asthma, and 126 non-asthmatic controls. PCR methods, including gene sequencing to identify rhinovirus strains, were used to identify viral pathogens in nasal washes. Results were examined in relation to wheezing, total IgE, allergen-specific IgE antibody, and levels of expired nitric oxide (FENO). Results Sixty-four percent of wheezing children compared to 13% of children with stable asthma and 17% of the non-asthmatic controls tested positive for rhinovirus (p<0.001 for both comparisons). Among wheezing subjects, 75% of the rhinoviruses detected were Group C strains. High titers of IgE antibodies to dust mite allergen (especially Dermatophagoides sp) were common and correlated significantly with levels of total IgE and FENO. The greatest risk for wheezing was observed among children with titers of IgE antibodies to dust mite ≥17.5 IU/ml who tested positive for rhinovirus (odds ratio for wheezing: 31.5; 95% CI 8.3–108, p<0.001). Conclusions High titers of IgE antibody to dust mite allergen were common and significantly increased the risk for acute wheezing provoked by rhinovirus among asthmatic children. PMID:22560151

  13. High titers of IgE antibody to dust mite allergen and risk for wheezing among asthmatic children infected with rhinovirus.

    Science.gov (United States)

    Soto-Quiros, Manuel; Avila, Lydiana; Platts-Mills, Thomas A E; Hunt, John F; Erdman, Dean D; Carper, Holliday; Murphy, Deborah D; Odio, Silvia; James, Hayley R; Patrie, James T; Hunt, William; O'Rourke, Ashli K; Davis, Michael D; Steinke, John W; Lu, Xiaoyan; Kennedy, Joshua; Heymann, Peter W

    2012-06-01

    The relevance of allergic sensitization, as judged by titers of serum IgE antibodies, to the risk of an asthma exacerbation caused by rhinovirus is unclear. We sought to examine the prevalence of rhinovirus infections in relation to the atopic status of children treated for wheezing in Costa Rica, a country with an increased asthma burden. The children enrolled (n= 287) were 7 through 12 years old. They included 96 with acute wheezing, 65 with stable asthma, and 126 nonasthmatic control subjects. PCR methods, including gene sequencing to identify rhinovirus strains, were used to identify viral pathogens in nasal washes. Results were examined in relation to wheezing, IgE, allergen-specific IgE antibody, and fraction of exhaled nitric oxide levels. Sixty-four percent of wheezing children compared with 13% of children with stable asthma and 13% of nonasthmatic control subjects had positive test results for rhinovirus (P< .001 for both comparisons). Among wheezing subjects, 75% of the rhinoviruses detected were group C strains. High titers of IgE antibodies to dust mite allergen (especially Dermatophagoides species) were common and correlated significantly with total IgE and fraction of exhaled nitric oxide levels. The greatest risk for wheezing was observed among children with titers of IgE antibodies to dust mite of 17.5 IU/mL or greater who tested positive for rhinovirus (odds ratio for wheezing, 31.5; 95% CI, 8.3-108; P< .001). High titers of IgE antibody to dust mite allergen were common and significantly increased the risk for acute wheezing provoked by rhinovirus among asthmatic children. Published by Mosby, Inc.

  14. Antibody titers to vaccination are not predictive of level of protection against a BVDV type 1b challenge in Bos indicus - Bos taurus steers.

    Science.gov (United States)

    Downey-Slinker, E D; Ridpath, J F; Sawyer, J E; Skow, L C; Herring, A D

    2016-09-30

    Subclinical illness associated with infection is thought to reduce performance and increase production costs in feedlot cattle, but underlying components remain largely unidentified. Vaccination is frequently used in feedlot settings but producers lack metrics that evaluate the effectiveness of vaccination programs. The goal of this study was to determine if levels of serum neutralizing antibody titers were predictive of levels of vaccine protection in a commercial setting. During this four-year study, Angus-Nellore steers housed in a production feedlot setting were assigned to 1 of 3 vaccine treatments: killed vaccine (kV), modified live virus (MLV) vaccine, or no vaccine (control), and were challenged with a noncytopathic 1b field strain of bovine viral diarrhea virus. Rectal temperature and levels of circulating lymphocytes and platelets were monitored following challenge. While no animals were diagnosed as clinically ill with respiratory disease, indicators of disease (pyrexia, lymphopenia, and thrombocytopenia) were observed. The MLV treatment elicited higher antibody titers to the vaccination than the kV, and calves in the MLV treatment had higher mean titers at challenge. The year that elicited the highest antibody response to the vaccination and the year with the lowest frequency of phenotypic responses to the challenge were not concurrent. The MLV treatment had the highest proportion, 34.68%, of animals that were protected against the challenge regardless of the pre-challenge antibody titer and had the fewest number of lymphopenia cases in response to the challenge. Both vaccine treatments mitigated thrombocytopenia when compared to the control treatment, and the MLV treatment reduced lymphopenia; however, these symptoms were not completely eliminated in vaccinated animals. Pyrexia was present in 40.11% of the animals, but no difference in the frequency of cases between treatments was observed. Pre-challenge vaccination response was not indicative of the

  15. Evolution of anti-Trypanosoma cruzi antibody production in patients with chronic Chagas disease: Correlation between antibody titers and development of cardiac disease severity.

    Directory of Open Access Journals (Sweden)

    Ingebourg Georg

    2017-07-01

    Full Text Available Chagas disease is one of the most important endemic infections in Latin America affecting around 6-7 million people. About 30-50% of patients develop the cardiac form of the disease, which can lead to severe cardiac dysfunction and death. In this scenario, the identification of immunological markers of disease progression would be a valuable tool for early treatment and reduction of death rates. In this observational study, the production of anti-Trypanosoma cruzi antibodies through a retrospective longitudinal follow-up in chronic Chagas disease patients´ cohort and its correlation with disease progression and heart commitment was evaluated. Strong inverse correlation (ρ = -0.6375, p = 0.0005 between anti-T. cruzi IgG1 titers and left ventricular ejection fraction (LVEF in chronic Chagas cardiomyopathy (CCC patients were observed after disease progression. Elevated levels of anti-T. cruzi IgG3 titers were detected in all T. cruzi-infected patients, indicating a lack of correlation of this IgG isotype with disease progression. Furthermore, low levels of anti-T. cruzi IgG2, IgG4, and IgA were detected in all patients through the follow-up. Although without statistical significance anti-T. cruzi IgE tends to be more reactive in patients with the indeterminate form (IND of the disease (p = 0.0637. As this study was conducted in patients with many years of chronic disease no anti-T. cruzi IgM was detected. Taken together, these results indicate that the levels of anti-T. cruzi IgG1 could be considered to seek for promising biomarkers to predict the severity of chronic Chagas disease cardiomyopathy.

  16. Evolution of anti-Trypanosoma cruzi antibody production in patients with chronic Chagas disease: Correlation between antibody titers and development of cardiac disease severity

    Science.gov (United States)

    Georg, Ingebourg; Hasslocher-Moreno, Alejandro Marcel; Xavier, Sergio Salles; de Holanda, Marcelo Teixeira; Bonecini-Almeida, Maria da Gloria

    2017-01-01

    Chagas disease is one of the most important endemic infections in Latin America affecting around 6–7 million people. About 30–50% of patients develop the cardiac form of the disease, which can lead to severe cardiac dysfunction and death. In this scenario, the identification of immunological markers of disease progression would be a valuable tool for early treatment and reduction of death rates. In this observational study, the production of anti-Trypanosoma cruzi antibodies through a retrospective longitudinal follow-up in chronic Chagas disease patients´ cohort and its correlation with disease progression and heart commitment was evaluated. Strong inverse correlation (ρ = -0.6375, p = 0.0005) between anti-T. cruzi IgG1 titers and left ventricular ejection fraction (LVEF) in chronic Chagas cardiomyopathy (CCC) patients were observed after disease progression. Elevated levels of anti-T. cruzi IgG3 titers were detected in all T. cruzi-infected patients, indicating a lack of correlation of this IgG isotype with disease progression. Furthermore, low levels of anti-T. cruzi IgG2, IgG4, and IgA were detected in all patients through the follow-up. Although without statistical significance anti-T. cruzi IgE tends to be more reactive in patients with the indeterminate form (IND) of the disease (p = 0.0637). As this study was conducted in patients with many years of chronic disease no anti-T. cruzi IgM was detected. Taken together, these results indicate that the levels of anti-T. cruzi IgG1 could be considered to seek for promising biomarkers to predict the severity of chronic Chagas disease cardiomyopathy. PMID:28723905

  17. PEMBUATAN DAN STANDARISASI ANTIGEN AI H5N1 KOMERSIAL UNTUK MONITORING TITER ANTIBODI HASIL VAKSINASI AI DI INDUSTRI PETERNAKAN AYAM

    Directory of Open Access Journals (Sweden)

    Retno D. Soejoedono

    2012-04-01

    Full Text Available Vaccination is one of the chosen strategy for controling AI H5N1 in Indonesia. Vaccination able to induce protective antibodies against AI but unable to inhibit viral infection. Determination of antibody titers in the serum from bird vaccinated with AI-H5N1 vaccine consisting of 2 or 3 different AI virus isolates difficult to be meassured if the antigen for HI test is uncalibrated yet. Furthermore, the determination of a minimum protective antibody titer against the challenge of AI virus circulating in the field at this time needs to be done. This study aims to determine the H5N1 AI virus antigen for standart HI test and the minimum titre of antibodies that able neutralize virus infection. As much as 55 chickens were divided into 11 groups, 10 groups vaccinated with commercial AI vaccine and AI H5N1 field isolat antigen. Four types of commercial vaccines were veccinated to one group and seven other groups vaccinated with the antigen AI Legok 2004, Nagrak Ag 2009, Ag Lawang 2010, as well as polyvalent Ag combination of these three types of antigen. After third vaccinations, the presence of antibodieswere meassured by HI test. Serum with a titer test 26-28 were tested for the capability of virus neutralizationin using virus neutralization test against three different H5N1 AI virus field isolates. The test results showed that the H5N1 subtype AI virus antigen representative as standart antigen for HI test is antigen Legok 2004 and the minimum titer which able neutralize H5N1 AI virus field isolates 28

  18. Relevance of specific IgE antibody titer to the prevalence, severity, and persistence of asthma among 19-year-olds in northern Sweden.

    Science.gov (United States)

    Perzanowski, Matthew S; Ronmark, Eva; James, Hayley R; Hedman, Linnea; Schuyler, Alexander J; Bjerg, Anders; Lundback, Bo; Platts-Mills, Thomas A E

    2016-12-01

    Although sensitization to indoor allergens is strongly associated with asthma, there are questions as to how this relates to asthma symptoms. We sought to study the relevance of IgE antibodies to cat and dog allergens in an area in which (1) the climate discourages cockroach, fungal, and mite growth and (2) dander allergens are known to be present in schools and houses without animals. IgE to 8 allergens was tested in 963 sera from a population-based study on 19-year-olds, and associations with asthma symptoms, diagnosis, and treatment were examined. In positive sera IgE to specific cat and dog allergens was also assayed. IgE specific for animal dander had the highest prevalence and strongest relationship to asthma diagnosis. Furthermore, asthma severity, as judged by the frequency of symptoms and use of treatment, was directly associated with the titer of IgE antibodies to animal dander. Among the 103 subjects who had current asthma at age 19 years, 50 had asthma before age 12 years. Among those 50, the odds ratios for asthma related to any IgE antibodies to animal dander or high-titer IgE antibodies (≥17.5 IU/mL) were 9.2 (95% CI, 4.9-17) and 13 (95% CI, 6.9-25), respectively. In multivariable analysis IgE antibodies to Fel d 1 and Can f 5 were each associated with current asthma. High-titer IgE antibodies to cat and dog allergens were strongly associated with the diagnosis, severity, and persistence of asthma; however, a large proportion of patients with current asthma did not live in a house with a cat or dog. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  19. The effects of wet cupping on serum high-sensitivity C-reactive protein and heat shock protein 27 antibody titers in patients with metabolic syndrome.

    Science.gov (United States)

    Farahmand, Seyed Kazem; Gang, Li Zhi; Saghebi, Seyed Ahmad; Mohammadi, Maryam; Mohammadi, Shabnam; Mohammadi, Ghazaleh; Ferns, Gordan A; Ghanbarzadeh, Majid; Razmgah, Gholamreza Ghayour; Ramazani, Zahra; Ghayour-Mobarhan, Majid; Esmaily, Habibollah; Bahrami Taghanaki, Hamidreza; Azizi, Hoda

    2014-08-01

    It has previously been reported that increased level of serum heat shock proteins (Hsps) antibody in patients with metabolic syndrome. It is possible that the expression of Hsp and inflammatory markers can be affected by cupping and traditional Chinese medicine. There is a little data investigating the effects of cupping on markers of inflammation and Hsp proteins, hence, the objective of this study was evaluation of the effects of wet cupping on serum high-sensitivity C-reactive protein (hs-CRP) and Hsp27 antibody titers in patients with metabolic syndrome. Serum Hs-CRP and Hsp27 antibody titers were assessed in samples from 126 patients with metabolic syndrome (18-65 years of age) at baseline, and after 6 and 12 weeks after treatment. One hundred and twenty-six patients were randomly divided into the experimental group treated with wet cupping combined with dietary advice, and the control group treated with dietary advice alone using a random number table. Eight patients in case group and five subjects in control groups were excluded from the study. Data were analyzed using SPSS 15.0 software and a repeated measure ANCOVA. Serum hs-CRP titers did not change significantly between groups (p>0.05) and times (p=0.27). The same result was found for Hsp27 titers (p>0.05). Wet-cupping on the interscapular region has no effect on serum hs-CRP and Hsp27 patients with metabolic syndrome. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Recent Developments in Antibody-Based Assays for the Detection of Bacterial Toxins

    Directory of Open Access Journals (Sweden)

    Kui Zhu

    2014-04-01

    Full Text Available Considering the urgent demand for rapid and accurate determination of bacterial toxins and the recent promising developments in nanotechnology and microfluidics, this review summarizes new achievements of the past five years. Firstly, bacterial toxins will be categorized according to their antibody binding properties into low and high molecular weight compounds. Secondly, the types of antibodies and new techniques for producing antibodies are discussed, including poly- and mono-clonal antibodies, single-chain variable fragments (scFv, as well as heavy-chain and recombinant antibodies. Thirdly, the use of different nanomaterials, such as gold nanoparticles (AuNPs, magnetic nanoparticles (MNPs, quantum dots (QDs and carbon nanomaterials (graphene and carbon nanotube, for labeling antibodies and toxins or for readout techniques will be summarized. Fourthly, microscale analysis or minimized devices, for example microfluidics or lab-on-a-chip (LOC, which have attracted increasing attention in combination with immunoassays for the robust detection or point-of-care testing (POCT, will be reviewed. Finally, some new materials and analytical strategies, which might be promising for analyzing toxins in the near future, will be shortly introduced.

  1. ICAM-1-based rabies virus vaccine shows increased infection and activation of primary murine B cells in vitro and enhanced antibody titers in-vivo.

    Science.gov (United States)

    Norton, James E; Lytle, Andrew G; Shen, Shixue; Tzvetkov, Evgeni P; Dorfmeier, Corin L; McGettigan, James P

    2014-01-01

    We have previously shown that live-attenuated rabies virus (RABV)-based vaccines infect and directly activate murine and human primary B cells in-vitro, which we propose can be exploited to help develop a single-dose RABV-based vaccine. Here we report on a novel approach to utilize the binding of Intracellular Adhesion Molecule-1 (ICAM-1) to its binding partner, Lymphocyte Function-associated Antigen-1 (LFA-1), on B cells to enhance B cell activation and RABV-specific antibody responses. We used a reverse genetics approach to clone, recover, and characterize a live-attenuated recombinant RABV-based vaccine expressing the murine Icam1 gene (rRABV-mICAM-1). We show that the murine ICAM-1 gene product is incorporated into virus particles, potentially exposing ICAM-1 to extracellular binding partners. While rRABV-mICAM-1 showed 10-100-fold decrease in viral titers on baby hamster kidney cells compared to the parental virus (rRABV), rRABV-mICAM-1 infected and activated primary murine B cells in-vitro more efficiently than rRABV, as indicated by significant upregulation of CD69, CD40, and MHCII on the surface of infected B cells. ICAM-1 expression on the virus surface was responsible for enhanced B cell infection since pre-treating rRABV-mICAM-1 with a neutralizing anti-ICAM-1 antibody reduced B cell infection to levels observed with rRABV alone. Furthermore, 100-fold less rRABV-mICAM-1 was needed to induce antibody titers in immunized mice equivalent to antibody titers observed in rRABV-immunized mice. Of note, only 10(3) focus forming units (ffu)/mouse of rRABV-mICAM-1 was needed to induce significant anti-RABV antibody titers as early as five days post-immunization. As both speed and potency of antibody responses are important in controlling human RABV infection in a post-exposure setting, these data show that expression of Icam1 from the RABV genome, which is then incorporated into the virus particle, is a promising strategy for the development of a single-dose RABV

  2. ICAM-1-based rabies virus vaccine shows increased infection and activation of primary murine B cells in vitro and enhanced antibody titers in-vivo.

    Directory of Open Access Journals (Sweden)

    James E Norton

    Full Text Available We have previously shown that live-attenuated rabies virus (RABV-based vaccines infect and directly activate murine and human primary B cells in-vitro, which we propose can be exploited to help develop a single-dose RABV-based vaccine. Here we report on a novel approach to utilize the binding of Intracellular Adhesion Molecule-1 (ICAM-1 to its binding partner, Lymphocyte Function-associated Antigen-1 (LFA-1, on B cells to enhance B cell activation and RABV-specific antibody responses. We used a reverse genetics approach to clone, recover, and characterize a live-attenuated recombinant RABV-based vaccine expressing the murine Icam1 gene (rRABV-mICAM-1. We show that the murine ICAM-1 gene product is incorporated into virus particles, potentially exposing ICAM-1 to extracellular binding partners. While rRABV-mICAM-1 showed 10-100-fold decrease in viral titers on baby hamster kidney cells compared to the parental virus (rRABV, rRABV-mICAM-1 infected and activated primary murine B cells in-vitro more efficiently than rRABV, as indicated by significant upregulation of CD69, CD40, and MHCII on the surface of infected B cells. ICAM-1 expression on the virus surface was responsible for enhanced B cell infection since pre-treating rRABV-mICAM-1 with a neutralizing anti-ICAM-1 antibody reduced B cell infection to levels observed with rRABV alone. Furthermore, 100-fold less rRABV-mICAM-1 was needed to induce antibody titers in immunized mice equivalent to antibody titers observed in rRABV-immunized mice. Of note, only 10(3 focus forming units (ffu/mouse of rRABV-mICAM-1 was needed to induce significant anti-RABV antibody titers as early as five days post-immunization. As both speed and potency of antibody responses are important in controlling human RABV infection in a post-exposure setting, these data show that expression of Icam1 from the RABV genome, which is then incorporated into the virus particle, is a promising strategy for the development of a

  3. Detection of high titers of antibody against Helicobacter cysteine-rich proteins A, B, C, and E in Helicobacter pylori-infected individuals.

    Science.gov (United States)

    Mittl, Peer R E; Lüthy, Lucas; Reinhardt, Christoph; Joller, Hellen

    2003-07-01

    The family of Helicobacter cysteine-rich proteins (Hcp) constitutes one of the largest protein families that are specific for proteobacteria from the delta/epsilon subgroup. Most of the proteins belonging to this family have so far only been recognized on the genome level. To investigate the expression of Hcp proteins in vivo we analyzed titers of antibody against HcpA (HP0211), HcpB (HP0336), HcpC (HP1098), and HcpE (HP0235) in sera from 30 Helicobacter pylori-positive individuals and in a control group of six H. pylori-negative individuals. Significantly higher titers of antibody were observed for H. pylori-positive individuals (P HcpE immunoglobulin G titers in H. pylori-positive individuals (correlation > 0.7), but there is only a weak correlation for HcpB (correlation HcpE are present in the genomes of strains 26695 and J99, whereas HcpB is absent from most strains. Since Hcp proteins are specific for H. pylori, immunological assays including Hcp proteins might be of value to detect H. pylori infection and perhaps to distinguish among different groups of H. pylori-positive patients.

  4. High-throughput antibody microarray for bacteria and toxins

    Science.gov (United States)

    Ingestion of pathogenic bacteria in foods often results in illnesses that are of worldwide concern. Hence, our research efforts have focused on developing screening tests capable of multiplexed detection of foodborne bacteria and associated toxins. In this study, we describe the combination of a s...

  5. Toxins

    Science.gov (United States)

    Toxins are substances created by plants and animals that are poisonous to humans. Toxins also include some medicines that are helpful in small doses, but poisonous in large amounts. Most toxins that cause problems ...

  6. Staphylococcus aureus nasal carriage in rheumatoid arthritis: antibody response to toxic shock syndrome toxin-1.

    OpenAIRE

    Tabarya, D; Hoffman, W L

    1996-01-01

    OBJECTIVE: To determine the prevalence of Staphylococcus aureus nasal carriage and to compare antibody responses to two superantigens, staphylococcal toxic shock syndrome toxin-1 (TSST-1) and staphylococcal enterotoxin A (SEA), in rheumatoid arthritis patients and normal subjects. METHODS: 88 rheumatoid arthritis patients and 110 control subjects were cultured for nasal carriage of S aureus; 62 isolates were bacteriophage typed. Twenty five patients and 11 spouses were tested for antibodies t...

  7. Open-label, dose escalation phase I study in healthy volunteers to evaluate the safety and pharmacokinetics of a human monoclonal antibody to Clostridium difficile toxin A.

    Science.gov (United States)

    Taylor, Claribel P; Tummala, Sanjeev; Molrine, Deborah; Davidson, Lisa; Farrell, Richard J; Lembo, Anthony; Hibberd, Patricia L; Lowy, Israel; Kelly, Ciaran P

    2008-06-25

    Recent data suggest that Clostridium difficile-associated diarrhea is becoming more severe and difficult to treat. Antibody responses to C. difficile toxin A are protective against symptomatic disease and recurrence. We examined the safety and pharmacokinetics (pk) of a novel neutralizing human monoclonal antibody against C. difficile toxin A (CDA1) in healthy adults. Five cohorts with 6 subjects each received a single intravenous infusion of CDA1 at escalating doses of 0.3, 1, 5, 10, and 20 mg/kg. Safety evaluations took place on days 1, 2, 3, 7, 14, 28, and 56 post-infusion. Samples for pk analysis were obtained before and after infusion, and at each safety evaluation. Serum CDA1 antibody concentrations and human anti-human antibody (HAHA) titers were measured with enzyme-linked immunosorbent assays. A noncompartmental model was used for pk analysis. Thirty subjects were enrolled. The median age was 27.5 yrs. There were no serious adverse events (AE) related to CDA1. Twenty-one of the 48 reported non-serious adverse events were possibly related to CDA1, and included transient blood pressure changes requiring no treatment, nasal congestion, headache, abdominal cramps, nausea, and self-limited diarrhea. Serum CDA1 concentrations increased with escalating doses: mean C(max) ranged from 6.82 microg/ml for the 0.3 mg/kg cohort to 511 microg/ml for the 20 mg/kg cohort. The geometric mean values of the half-life of CDA1 ranged between 25.3 and 31.8 days, and the volume of distribution approximated serum. No subject formed detectable HAHA titers. Administration of CDA1 as a single intravenous infusion was safe and well tolerated. C(max) increased proportionally with increasing doses. A randomized study of CDA1 in patients with C. difficile associated diarrhea is underway.

  8. Cancer development based on chronic active gastritis and resulting gastric atrophy as assessed by serum levels of pepsinogen and Helicobacter pylori antibody titer.

    Science.gov (United States)

    Yoshida, Takeichi; Kato, Jun; Inoue, Izumi; Yoshimura, Noriko; Deguchi, Hisanobu; Mukoubayashi, Chizu; Oka, Masashi; Watanabe, Mika; Enomoto, Shotaro; Niwa, Toru; Maekita, Takao; Iguchi, Mikitaka; Tamai, Hideyuki; Utsunomiya, Hirotoshi; Yamamichi, Nobutake; Fujishiro, Mitsuhiro; Iwane, Masataka; Takeshita, Tatsuya; Ushijima, Toshikazu; Ichinose, Masao

    2014-03-15

    Our study investigated the relationship between gastric cancer development and activity of Helicobacter pylori-associated chronic gastritis or the resulting chronic atrophic gastritis (CAG). A cohort of 4,655 healthy asymptomatic subjects, in whom serum pepsinogen (PG) and H. pylori antibody titer had been measured to assess the activity and stage of H. pylori-associated chronic gastritis, was followed for up to 16 years, and cancer development was investigated. In subjects with a serologically diagnosed healthy stomach (H. pylori-negative/CAG-negative), cancer incidence rate was low, at 16/100,000 person-years. With the establishment of H. pylori infection and progression of chronic gastritis, significant stepwise cancer risk elevations were seen from CAG-free subjects (H. pylori-positive/CAG-negative) [hazard ratio (HR) = 8.9, 95% confidence interval (CI) = 2.7-54.7] to subjects with CAG (H. pylori-positive/CAG-positive) (HR = 17.7, 95% CI = 5.4-108.6) and finally to subjects with metaplastic gastritis (H. pylori-negative/CAG-positive) (HR = 69.7, 95% CI = 13.6-502.9). In H. pylori-infected CAG-free subjects, significantly elevated cancer risk was observed in the subgroup with active inflammation-based high PG II level or potent immune response-based high H. pylori antibody titer; the former was associated with a particularly high risk of diffuse-type cancer, and both subgroups showed high cancer incidence rates of around 250/100,000 person-years, comparable to that in subjects with CAG. No such risk elevation was observed in H. pylori-infected subjects with CAG. These results clearly indicate that gastric cancer develops mainly from the gastritis-atrophy-metaplasia-cancer sequence and partly from active inflammation-based direct carcinogenesis, and that serum levels of PG and H. pylori antibody titer provide indices of cancer development in H. pylori-infected subjects. © 2013 UICC.

  9. Growth Performance, Carcass Characteristics, Antibody Titer and Blood Parameters in Broiler Chickens Fed Dietary Myrtle (Myrtus communis Essential Oil as an Alternative to Antibiotic Growth Promoter

    Directory of Open Access Journals (Sweden)

    Mahmoodi Bardzardi M

    2014-03-01

    Full Text Available This experiment was conducted to determine the effects of Myrtle Essential Oil (MEO on growth performance, carcass characteristics, antibody titer and blood parameters of broiler chickens. A total of 200 Ross 308 broiler chickens were allocated to five dietary treatments with four replicates of 10 birds each. Dietary treatments were prepared by formulating a corn-soybean meal-based diet free of antibiotics (Control and supplementing the basal diet with three levels of MEO at 100, 200, 300 mg/Kg or antibiotic Flavophospholipol (FPL at 600 mg/Kg. The results showed that diets supplemented with MEO and FPL increased the feed intake, body weight gain and improved the feed conversion ratio compared to the control treatment (P. The relative carcass weight was significantly increased, whereas the weight of gastrointestinal tract and liver were decreased in broilers fed MEO (P. Supplementing the basal diet with MEO increased the antibody titers against Avian Influenza Virus (AIV and Newcastle disease Virus (NDV, although supplementing diet with 200 mg/Kg of MEO was more effective (P. Broilers fed MEO diets especially at the level of 300 mg/Kg had a lower white blood cells count and heterophil, heterophil to lymphocyte ratio, mean corpuscular volume and mean corpuscular hemoglobin, but a higher lymphocyte and red blood cells count (P. In conclusion, data showed that diet supplemented with MEO improved the growth performance and increased antibody titers against AIV and NDV, especially at the level of 200 mg/Kg, in broiler chickens and could be an adequate alternative to antibiotics.

  10. Poor Long-Term Efficacy of Prevnar-13 in Sickle Cell Disease Mice Is Associated with an Inability to Sustain Pneumococcal-Specific Antibody Titers.

    Directory of Open Access Journals (Sweden)

    Steven M Szczepanek

    Full Text Available One of the most common causes of morbidity and mortality in children with sickle cell disease (SCD is infection with the pneumococcal bacterium (Streptococcus pneumoniae. Unfortunately, the polysaccharide-conjugate vaccine appears to be less effective in individuals with SCD when compared to the general population. We sought to better understand the relative efficacy of pneumococcal vaccination in a SCD mouse challenge model.Transgenic control and SCD mice were monitored for mortality after intranasal pneumococcal infection or pneumococcal vaccination with Prevnar-13 and type-matched challenge. Anti-pneumococcal antibody titers were measured by ELISA and opsonophagocytosis was measured in vitro.Mortality after pneumococcal infection was similar between control and SCD mice. However, after three intramuscular polysaccharide-conjugate vaccinations, all control mice were protected following high-dose intranasal infection, whereas 60% of SCD mice died. Anti-pneumococcal antibody titers showed initial IgG and IgM responses in both groups, but waning titers were observed in the SCD group, even after boosting. When functionally assayed in vitro, serum from SCD mice 13 weeks after a second booster shot maintained little to no ability to opsonize pneumococci, while serum from control mice sustained a significantly higher capacity opsonization. Thus, it appears that SCD mice do not maintain antibody responses to pneumococcal polysaccharides after Prevnar-13 vaccination, thereby leaving them susceptible to mortality after type-matched infection.Our results emphasize the need to better understand the correlates of immune protection in SCD so that pneumococcal vaccines can be improved and mortality reduced in this susceptible population.

  11. Detection of High Titers of Antibody against Helicobacter Cysteine-Rich Proteins A, B, C, and E in Helicobacter pylori-Infected Individuals

    OpenAIRE

    Mittl, Peer R. E.; Lüthy, Lucas; Reinhardt, Christoph; Joller, Hellen

    2003-01-01

    The family of Helicobacter cysteine-rich proteins (Hcp) constitutes one of the largest protein families that are specific for proteobacteria from the delta/epsilon subgroup. Most of the proteins belonging to this family have so far only been recognized on the genome level. To investigate the expression of Hcp proteins in vivo we analyzed titers of antibody against HcpA (HP0211), HcpB (HP0336), HcpC (HP1098), and HcpE (HP0235) in sera from 30 Helicobacter pylori-positive individuals and in a c...

  12. Recombinant antivenoms based on mixtures of human antibodies against D. jamesoni toxins

    DEFF Research Database (Denmark)

    Pus, Urska; Harrison, Robert; Andersen, Mikael Rørdam

    Each year, more than 5 million people worldwide are affected by a snakebite, resulting in 150,000 deaths, and 400,000 amputations. The current medical treatment against envenoming is based on the administration of an animal-derived antiserum, containing antibodies against snake venom toxins. Due...

  13. ANTIBODY TITER AGAINST HBSAGIN CHILDREN ENTERING ELEMENTARY SCHOOL WHO WERE VACCINATED AGAINST HEPATITIS B AT BIRTH: SBAHR.E.KORD CITY

    Directory of Open Access Journals (Sweden)

    K MOSTAFAVIZADEH

    2001-09-01

    Full Text Available Introduction. Regarding the fact that hepatitis B and its complications is a serious problem routine vaccination against it is recommended at birth. Fortunately, since 1991 all infants in our country are vaccinated against the disease. This study was designed to evaluate hepatitis B vaccine induced immunity 5-6 years after vaccination. If antibody titer is below the protective level booster dose should be considered. Methods. This study is a cross-sectional one which 394 cases selected randomly. After filling up questionnaires sampling was performed and sample sera were checked out for anti HBsAg antibody by ELISA method.Results were announced as positive and negative. Some variables Such as age, gender, growth and development and time of vaccination also were evaluated. Results. From the total number of 394 cases, 142 (36 percent had antibody title less than (10 MIU which is not protective. Rate of negative response was 32.2 percent for girls and 39 percent for boys. The same rate for children of 2-2.5, 2.5-3.5and over 3 kg weight at birth was 44 percent 36.percent and 34.8 percent respectively. Regarding the time, 16 cases had delayed vaccination with 44 percent negative response. Rate of negative response in children who received regular vaccination was 35.7 percent. Negative response rate for 25 cases above the acceptable level of growth was 8 percent and for 6 cases below the level was 17 percent. In rural and urban population negative response rate was 35.4 percent and 36.7 percent respectively. Discussion. Cases with negative response are suscoptible to infection so it is recommended to 1: Carryout investigations to determine causes of decline in antibody titer. 2: Carryout investigations in other parts of country to recheck the results of this study. 3: administer booster dose to high-risk cases with negative response.

  14. A comparison of titers of anti-Brucella antibodies of naturally infected and healthy vaccinated cattle by standard tube agglutination test, microtiter plate agglutination test, indirect hemagglutination assay, and indirect enzyme-linked immunosorbent assay

    Directory of Open Access Journals (Sweden)

    Anju Mohan

    2016-07-01

    Full Text Available Aim: We determined the antibody response in cattle naturally infected with brucellosis and normal healthy adult cattle vaccinated during calf hood with strain 19. Materials and Methods: The antibody titers were measured by standard tube agglutination test (STAT, microtiter plate agglutination test (MAT, indirect hemagglutination assay (IHA, and indirect enzyme-linked immunosorbent assay (iELISA as per standard protocols. Results: The mean STAT titers were 1.963±0.345 in infected cattle and 1.200±0.155 in healthy vaccinated cattle. The difference was extremely significant (p<0.0001. The mean MAT titers were 2.244±0.727 in infected cattle and 1.200±0.155 in healthy vaccinated cattle. The difference was very significant (p<0.005. The mean IHA titers in infected cattle were 2.284±0.574, and those in healthy vaccinated cattle were 1.200±0.155. The difference was extremely significant (p=0.0002. However, the difference in mean iELISA titers of infected cattle (1.3678±0.014 and healthy vaccinated cattle (1.367±0.014 was non-significant. The infected animals showed very high titers of agglutinating antibodies compared to the vaccinated animals. However, it cannot be ascertained whether these antibodies are due to vaccine or response to infection. Since the infected animals had been vaccinated earlier, the current infection may suggest that vaccination was unable to induce protective levels of antibody. The heightened antibody response after infection may also indicate a secondary immune response to the antigens common to the vaccine strain and wild Brucella organisms. Conclusion: The brucellosis infected animals showed very high titers of agglutinating antibodies compared to the vaccinated animals.

  15. Interleukin-15 Increases Vaccine Efficacy through a Mechanism Linked to Dendritic Cell Maturation and Enhanced Antibody Titers

    Science.gov (United States)

    2007-11-26

    of STEBVax, 143 g of alhydrogel ( Alh ), and 0.1 g, 0.5 g, or 5 g of IL-15/mouse in a 200-l volume of PBS. The ratio of vaccine to alhydrogel was 1...Coadministration of IL-15 with STEBVax and alhydrogel ( Alh ) increased the protection of mice from lethal SEB toxin chal- lenge. (A) BALB/c mice were vaccinated with

  16. FX knockout CHO hosts can express desired ratios of fucosylated or afucosylated antibodies with high titers and comparable product quality.

    Science.gov (United States)

    Louie, Salina; Haley, Benjamin; Marshall, Brett; Heidersbach, Amy; Yim, Mandy; Brozynski, Martina; Tang, Danming; Lam, Cynthia; Petryniak, Bronislawa; Shaw, David; Shim, Jeongsup; Miller, Aaron; Lowe, John B; Snedecor, Brad; Misaghi, Shahram

    2017-03-01

    During antibody dependent cell cytotoxicity (ADCC) the target cells are killed by monocytes and natural killer cells. ADCC is enhanced when the antibody heavy chain's core N-linked glycan lacks the fucose molecule(s). Several strategies have been utilized to generate fully afucosylated antibodies. A commonly used and efficient approach has been knocking out the FUT8 gene of the Chinese hamster ovary (CHO) host cells, which results in expression of antibody molecules with fully afucosylated glycans. However, a major drawback of the FUT8-KO host is the requirement for undertaking two separate cell line development (CLD) efforts in order to obtain both primarily fucosylated and fully afucosylated antibody species for comparative studies in vitro and in vivo. Even more challenging is obtaining primarily fucosylated and FUT8-KO clones with similar enough product quality attributes to ensure that any observed ADCC advantage(s) can be strictly attributed to afucosylation. Here, we report generation and use of a FX knockout (FXKO) CHO host cell line that is capable of expressing antibody molecules with either primarily fucosylated or fully afucosylated glycan profiles with otherwise similar product quality attributes, depending on addition of fucose to the cell culture media. Hence, the FXKO host not only obviates the requirement for undertaking two separate CLD efforts, but it also averts the need for screening many colonies to identify clones with comparable product qualities. Finally, FXKO clones can express antibodies with the desired ratio of primarily fucosylated to afucosylated glycans when fucose is titrated into the production media, to allow achieving intended levels of FcγRIII-binding and ADCC for an antibody. Biotechnol. Bioeng. 2017;114: 632-644. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  17. [Use of monoclonal antibodies against horse immunoglobulin in an enzyme immunoassay of bacterial toxins and anatoxins].

    Science.gov (United States)

    Burkin, M A; Gal'vidis, I A; Iakovleva, I V; Sviridov, V V

    2007-01-01

    Immunization of BALB/c mice by horse antiserum against diphtheria made it possible to obtain IgG1 monoclonal antibodies (MoAbs) 2B7E4 specific for light chains of horse immunoglobulin (Ig). Unlike commercial preparations of anti-horse immunoglobulin antibodies, which are specific for the whole Ig molecule or its Fc-fragment, the peroxidase (HRP) conjugate of the MoAb, 2B7E4-HRP did not interact with human, mouse, rabbit, and sheep Igs, or horse albumin. The conjugate obtained was used with MoAbs against bacterial toxins and commercial horse anatoxins, as a universal reagent in sandwich enzyme immunoassay (ELISA) for bacterial toxins and anatoxins. The detection sensitivity of diphtheria toxin/anatoxin equaled 0.0005 Lf/ml; tetanus toxin and anatoxin were detected with sensitivities of 20 LD50/ml and 0.005 UI/ml, respectively. A similar sandwich ELISA for botulinum anatoxins (group measurement) allowed types A, B, and E to be detected at 0.02, 0.002, and 0.001 UI/ml, respectively; selective measurement was only possible in the case of type E anatoxin (0.001 UI/ml).

  18. RI-002, an intravenous immunoglobulin containing high titer neutralizing antibody to RSV and other respiratory viruses for use in primary immunodeficiency disease and other immune compromised populations.

    Science.gov (United States)

    Wasserman, Richard L; Greener, Benjamin N; Mond, James

    2017-12-01

    Novel immune globulin (IG) products (RI-002, RI-001) have been designed to provide protection against respiratory syncytial virus (RSV) mediated respiratory illness while at the same time meeting the manufacturing requirements established by FDA for antibody supplementation in immunocompromised subjects. Areas covered: This review covers the manufacture and development of both RI-001 and RI-002, including the selection of plasma donors for IG preparation with high-titers of anti-RSV antibody, in vitro, and preclinical data in the cotton rat model S. hispidus, and clinical trials including Phase II and compassionate use studies of RI-001 and a multi-center, pivotal Phase III study of RI-002 in PIDD patients. Expert commentary: The data demonstrate that RI-002 is efficacious in the prevention and treatment of RSV in preclinical normal and immune suppressed animal models and is safe and efficacious in the treatment of patients with various forms of primary immunodeficiency disease (PIDD). This product offers potential advantages over other available IG's for prophylaxis in immunocompromised patients requiring polyclonal immunoglobulin supplementation because of its unique antibody composition. In addition to its enhanced neutralizing anti-RSV activity and its polyclonal IG composition, there is preclinical data to support the use of RI-002 for humoral protection against other respiratory pathogens.

  19. Antibody titers in animal bite victims after post exposure vaccination with intradermally administered purified vero cell rabies vaccine using modified thai red cross regimen

    International Nuclear Information System (INIS)

    Hafeez, S.; Tahir, Z.

    2014-01-01

    To determine the seroconversion following rabies vaccination by intradermal route in cases of animal bite attending Anti rabies center, Lahore for post exposure prophylaxis. Study Design: Cross sectional descriptive study. Place and Duration: Antirabies center, Birdwood road Lahore, Microbiology laboratory, office of Bacteriologist, Government of Punjab, Lahore. Patients and Methods: Victims of all ages and both sexes having exposure with suspected rabid animal within 24 - 72 hours were included, fulfilling inclusion and exclusion criteria, over 3 months period from February to April 20. Patients of Category II and III wounds were included. Purified vero cell vaccine (PVR V) with antigenic content> 2.5 ml was used for intradermal vaccination according to modified Thai Red Cross regimen (2-2-2-0-2). Each victim received 0.1 ml intradermal dose on each deltoid on day 0, 3, 7 and 28th day of bite. Blood samples from victims were taken on day 0, 14 and 35. Antibody titers were estimated by ELISA kit. Results: Fifty cases were studied including 20 children. Male female ratio was 4:1. Optimum serocon version (> 0.5 IU/ml) was achieved in all cases by day 14. Antibody levels increased further (> 4 IV/ml) in 92% cases on day 35. Geometric mean titers were 3.2 IU/ml and 6.2 IU/ml on day 14 and 35 respectively. Conclusion: Intradermal route for cell culture rabies vaccine for postexposure prophylaxis in animal bite victims was efficacious and safe. The smaller dosage of vaccine was economically affordable by patients in referral centers. (author)

  20. A case-control study developing a model for predicting risk factors for high SeM-specific antibody titers after natural outbreaks of Streptococcus equi subsp equi infection in horses.

    Science.gov (United States)

    Boyle, Ashley G; Smith, Meagan A; Boston, Raymond C; Stefanovski, Darko

    2017-06-15

    OBJECTIVE To develop a risk prediction model for factors associated with an SeM-specific antibody titer ≥ 3,200 in horses after naturally occurring outbreaks of Streptococcus equi subsp equi infection and to validate this model. DESIGN Case-control study. ANIMALS 245 horses: 57 horses involved in strangles outbreaks (case horses) and 188 healthy horses (control horses). PROCEDURES Serum samples were obtained from the 57 cases over a 27.5-month period after the start of outbreaks; serum samples were obtained once from the 188 controls. A Bayesian mixed-effects logistic regression model was used to assess potential risk factors associated with an antibody titer ≥ 3,200 in the case horses. A cutoff probability for an SeM-specific titer ≥ 3,200 was determined, and the model was externally validated in the control horses. Only variables with a 95% credibility interval that did not overlap with a value of 1 were considered significant. RESULTS 9 of 57 (6%) case horses had at least 1 titer ≥ 3,200, and 7 of 188 (3.7%) of control horses had a titer ≥ 3,200. The following variables were found to be significantly associated with a titer ≥ 3,200 in cases: farm size > 20 horses (OR, 0.11), history of clinically evident disease (OR, 7.92), and male sex (OR, 0.11). The model had 100% sensitivity but only 24% specificity when applied to the 188 control horses (area under the receiver operating characteristic curve = 0.62.) CONCLUSIONS AND CLINICAL RELEVANCE Although the Bayesian mixed-effects logistic regression model developed in this study did not perform well, it may prove useful as an initial screening tool prior to vaccination. We suggest that SeM-specific antibody titer be measured prior to vaccination when our model predicts a titer ≥ 3,200.

  1. Associations among tooth loss, systemic inflammation and antibody titers to periodontal pathogens in Japanese patients with cardiovascular disease.

    Science.gov (United States)

    Aoyama, N; Suzuki, J-I; Kobayashi, N; Hanatani, T; Ashigaki, N; Yoshida, A; Shiheido, Y; Sato, H; Minabe, M; Izumi, Y; Isobe, M

    2018-02-01

    It is well known that there is a strong relationship between periodontitis and cardiovascular disease (CVD). Tooth loss reflects an end-stage condition of oral diseases, such as periodontitis. Infection with specific periodontal pathogens is known as a possible factor that influences development of CVD. The aim of this study was to assess the relationship between the number of residual teeth and systemic inflammatory conditions in patients with CVD. We divided 364 patients with CVD into four groups, according to the number of residual teeth: (i) ≥20 teeth; (ii) 10-19 teeth; (iii) 1-9 teeth; and (iv) edentulous. We recorded medical history, blood data and periodontal conditions. Serum samples were obtained and their IgG titers against three major periodontal pathogens were measured. Smoking rate and the prevalence of diabetes mellitus were higher in edentulous patients and in subjects with a few teeth compared with patients with many teeth. The levels of C-reactive protein were higher in patients with 1-9 teeth than in those with 10-19 teeth and with ≥20 teeth. The level of Porphyromonas gingivalis IgG in the group with 10-19 teeth was statistically higher than that in the group with ≥20 teeth. The level of P. gingivalis IgG in the edentulous group tended to be lower than that in the other groups. The patients with 1-9 teeth had the highest level of C-reactive protein among the four groups, and the patients with 10-19 teeth had the highest level of IgG to periodontal bacteria. We conclude that the number of remaining teeth may be used to estimate the severity of systemic inflammation in patients with CVD. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Replicating rather than nonreplicating adenovirus-human immunodeficiency virus recombinant vaccines are better at eliciting potent cellular immunity and priming high-titer antibodies.

    Science.gov (United States)

    Peng, Bo; Wang, Liqun Rejean; Gómez-Román, Victor Raúl; Davis-Warren, Alberta; Montefiori, David C; Kalyanaraman, V S; Venzon, David; Zhao, Jun; Kan, Elaine; Rowell, Thomas J; Murthy, Krishna K; Srivastava, Indresh; Barnett, Susan W; Robert-Guroff, Marjorie

    2005-08-01

    A major challenge in combating the human immunodeficiency virus (HIV) epidemic is the development of vaccines capable of inducing potent, persistent cellular immunity and broadly reactive neutralizing antibody responses to HIV type 1 (HIV-1). We report here the results of a preclinical trial using the chimpanzee model to investigate a combination vaccine strategy involving sequential priming immunizations with different serotypes of adenovirus (Ad)/HIV-1(MN)env/rev recombinants and boosting with an HIV envelope subunit protein, oligomeric HIV(SF162) gp140deltaV2. The immunogenicities of replicating and nonreplicating Ad/HIV-1(MN)env/rev recombinants were compared. Replicating Ad/HIV recombinants were better at eliciting HIV-specific cellular immune responses and better at priming humoral immunity against HIV than nonreplicating Ad-HIV recombinants carrying the same gene insert. Enhanced cellular immunity was manifested by a greater frequency of HIV envelope-specific gamma interferon-secreting peripheral blood lymphocytes and better priming of T-cell proliferative responses. Enhanced humoral immunity was seen in higher anti-envelope binding and neutralizing antibody titers and better induction of antibody-dependent cellular cytotoxicity. More animals primed with replicating Ad recombinants mounted neutralizing antibodies against heterologous R5 viruses after one or two booster immunizations with the mismatched oligomeric HIV-1(SF162) gp140deltaV2 protein. These results support continued development of the replicating Ad-HIV recombinant vaccine approach and suggest that the use of replicating vectors for other vaccines may prove fruitful.

  3. Whole-Chain Tick Saliva Proteins Presented on Hepatitis B Virus Capsid-Like Particles Induce High-Titered Antibodies with Neutralizing Potential.

    Directory of Open Access Journals (Sweden)

    Philipp Kolb

    Full Text Available Ticks are vectors for various, including pathogenic, microbes. Tick saliva contains multiple anti-host defense factors that enable ticks their bloodmeals yet also facilitate microbe transmission. Lyme disease-causing borreliae profit specifically from the broadly conserved tick histamine release factor (tHRF, and from cysteine-rich glycoproteins represented by Salp15 from Ixodes scapularis and Iric-1 from Ixodes ricinus ticks which they recruit to their outer surface protein C (OspC. Hence these tick proteins are attractive targets for anti-tick vaccines that simultaneously impair borrelia transmission. Main obstacles are the tick proteins´ immunosuppressive activities, and for Salp15 orthologs, the lack of efficient recombinant expression systems. Here, we exploited the immune-enhancing properties of hepatitis B virus core protein (HBc derived capsid-like particles (CLPs to generate, in E. coli, nanoparticulate vaccines presenting tHRF and, as surrogates for the barely soluble wild-type proteins, cysteine-free Salp15 and Iric-1 variants. The latter CLPs were exclusively accessible in the less sterically constrained SplitCore system. Mice immunized with tHRF CLPs mounted a strong anti-tHRF antibody response. CLPs presenting cysteine-free Salp15 and Iric-1 induced antibodies to wild-type, including glycosylated, Salp15 and Iric-1. The broadly distributed epitopes included the OspC interaction sites. In vitro, the anti-Salp15 antibodies interfered with OspC binding and enhanced human complement-mediated killing of Salp15 decorated borreliae. A mixture of all three CLPs induced high titered antibodies against all three targets, suggesting the feasibility of combination vaccines. These data warrant in vivo validation of the new candidate vaccines´ protective potential against tick infestation and Borrelia transmission.

  4. Antibody Microarray for E. coli O157:H7 and Shiga Toxin in Microtiter Plates

    Directory of Open Access Journals (Sweden)

    Andrew G. Gehring

    2015-12-01

    Full Text Available Antibody microarray is a powerful analytical technique because of its inherent ability to simultaneously discriminate and measure numerous analytes, therefore making the technique conducive to both the multiplexed detection and identification of bacterial analytes (i.e., whole cells, as well as associated metabolites and/or toxins. We developed a sandwich fluorescent immunoassay combined with a high-throughput, multiwell plate microarray detection format. Inexpensive polystyrene plates were employed containing passively adsorbed, array-printed capture antibodies. During sample reaction, centrifugation was the only strategy found to significantly improve capture, and hence detection, of bacteria (pathogenic Escherichia coli O157:H7 to planar capture surfaces containing printed antibodies. Whereas several other sample incubation techniques (e.g., static vs. agitation had minimal effect. Immobilized bacteria were labeled with a red-orange-fluorescent dye (Alexa Fluor 555 conjugated antibody to allow for quantitative detection of the captured bacteria with a laser scanner. Shiga toxin 1 (Stx1 could be simultaneously detected along with the cells, but none of the agitation techniques employed during incubation improved detection of the relatively small biomolecule. Under optimal conditions, the assay had demonstrated limits of detection of ~5.8 × 105 cells/mL and 110 ng/mL for E. coli O157:H7 and Stx1, respectively, in a ~75 min total assay time.

  5. Antibody-based magneto-elastic biosensors: potential devices for detection of pathogens and associated toxins.

    Science.gov (United States)

    Menti, C; Henriques, J A P; Missell, F P; Roesch-Ely, M

    2016-07-01

    This work describes the design and development process of an immunosensor. The creation of such devices goes through various steps, which complement each other, and choosing an efficient immobilization method that binds to a specific target is essential to achieve satisfactory diagnostic results. In this perspective, the emphasis here is on developing biosensors based on binding antigens/antibodies on particular surfaces of magneto-elastic sensors. Different aspects leading to the improvement of these sensors, such as the antibody structure, the chemical functionalization of the surface, and cross-linking antibody reticulation were summarized and discussed. This paper deals with the progress of magneto-elastic immunosensors to detect bacterial pathogens and associated toxins. Biologically modified surface characterization methods are further considered. Thus, research opportunities and trends of future development in these areas are finally discussed.

  6. One Injection of DsRed Followed by Bites from Transgenic Mosquitoes Producing DsRed in the Saliva Elicits a High Titer of Antibody in Mice.

    Science.gov (United States)

    Matsuoka, Hiroyuki; Sano, Gen-Ichiro; Hattori, Ryuta; Tomita, Hiroyuki; Yamamoto, Daisuke S; Hirai, Makoto

    2012-06-01

    It has been proposed that transgenic mosquitoes can be used as a "flying syringe" for infectious disease control. We succeeded in generating a transgenic (TG) mosquito, Anopheles stephensi, excreting and discharging DsRed in saliva. DsRed was deposited on the membrane where the TG mosquito probed with its proboscis. Repeated feeding by the TG mosquitoes induced anti-DeRed as well as anti-SG antibodies in mice. This indicates that the TG mosquitoes can immunize the animal. Moreover, in this report, we employed a pre-immunization method before exposing mice to the TG mosquitoes. We injected DsRed to mice to prepare memory B cells and exposed the mice to bites by the TG mosquitoes excreting DsRed. The mice produced a higher titer of antibody to DsRed, suggesting that the bites from TG mosquitoes act as a booster and that primary immunization with a vaccine protein and exposure to TG mosquitoes excreting the vaccine protein in the saliva produces a synergistic effect.

  7. Antibody titers and response to vaccination against hepatitis A and B in pediatric patients with portal hypertension.

    Science.gov (United States)

    Rosa, Mariana Nogueira de Paula; Hessel, Gabriel; Alves De Tommaso, Adriana María

    2008-09-01

    In Brazil, approximately 130 new cases of hepatitis A per 100,000 inhabitants occur annually and 15% of the population has been in contact with hepatitis B virus. Portal hypertension causes hypersplenism and reduces T cell production, which may lead to less effective response to hepatitis vaccination. The objective of the study was to evaluate the response to hepatitis A and B vaccination in patients with portal hypertension secondary to chronic liver disease or portal vein thrombosis. Twenty-three patients (2 to 18 years) with portal hypertension seen at the Pediatric Hepatology Service of Hospital das Clínicas, Universidade Estadual de Campinas, between 1994 and 2006 were studied. Hepatitis A and B serology was tested in all patients. Patients who had not been vaccinated before their visits received the vaccines during the study period. Patients who had been vaccinated before but had negative anti-HB antibodies received a booster dose, and their serology was repeated Blood counts were performed in each patient to assess for immunosuppression. Eighteen patients received hepatitis A vaccine and all became positive for anti-HAV antibodies. All patients had received hepatitis B vaccine and 17 (73.9%) were anti-HBs positive at the time of the study The other 6 received a booster dose and became anti-HBs positive afterward. The anti-HBs-positive and -negative patients did not differ significantly in age, leukocytes, lymphocytes, or duration between the vaccination and positive serology. In this study, hepatitis A vaccines elicited a 100% response and hepatitis B vaccine conferred protection and induced an anamnestic response in pediatric patients with portal hypertension.

  8. Development of an in Vitro Potency Assay for Anti-anthrax Lethal Toxin Neutralizing Antibodies

    Directory of Open Access Journals (Sweden)

    Sjoerd Rijpkema

    2012-01-01

    Full Text Available Lethal toxin (LT of Bacillus anthracis reduces the production of a number of inflammatory mediators, including transcription factors, chemokines and cytokines in various human cell lines, leading to down-regulation of the host inflammatory response. Previously we showed that the reduction of interleukin-8 (IL-8 is a sensitive marker of LT-mediated intoxication in human neutrophil-like NB-4 cells and that IL-8 levels are restored to normality when therapeutic monoclonal antibodies (mAb with toxin-neutralising (TN activity are added. We used this information to develop cell-based assays that examine the effects of TN therapeutic mAbs designed to treat LT intoxication and here we extend these findings. We present an in vitro assay based on human endothelial cell line HUVEC jr2, which measures the TN activity of therapeutic anti-LT mAbs using IL-8 as a marker for intoxication. HUVEC jr2 cells have the advantage over NB-4 cells that they are adherent, do not require a differentiation step and can be used in a microtitre plate format and therefore can facilitate high throughput analysis. This human cell-based assay provides a valid alternative to the mouse macrophage assay as it is a more biologically relevant model of the effects of toxin-neutralising antibodies in human infection.

  9. [Following 90 patients with antiphospholipid syndrome with antibody titers and correlations with clinical manifestations: symptoms of the disease, a new antibody and correlations with clinical manifestations in the Israeli population].

    Science.gov (United States)

    Marai, I; Levi, Y; Godard, G; Shoenfeld, Y

    2001-06-01

    The antiphospholipid syndrome (APS) is defined by the presence of antiphospholipid antibodies (aPLs) with venous or arterial thrombosis, recurrent pregnancy loss or thrombocytopenia. The syndrome can be either primary or secondary to an underlying condition, most commonly systemic lupus erythematosus (SLE). The purpose of the study was to review the manifestations of the APS in Israeli patients and to investigate the difference between patients with primary or secondary syndrome. Analysis of the correlation between the manifestations of the disease and the antibody titers [LA (lupus anticoagulant), IgG aCL (anticardiolipin), IgM aCL] was also performed. In the study there were 90 patients with APS in the Sheba Medical Center. The clinical findings for all patients were recorded according to established protocol. Arterial thrombotic events were present in 51.1% of the patients; cerebral ischemic attacks were the most frequent arterial events. Venous thrombotic events were present in 45.6% patients; deep venous thrombosis was the most frequent venous event. Obstetric complications were found in 37.3% of patients; the most frequent complication was abortions. The clinical findings of patients with primary or secondary syndrome were similar. Patients with APS associated with lupus had a high prevalence of hemolytic anemia (28.6% v 3.3%; P = 0.001), and ANA (antinuclear antibody) (75% v 12.9%; P = 0.0001). There was no correlation between the antibody titers (LA, IgG aCL, IgM aCL) and clinical manifestations. The patients received anticoagulant treatment and antiaggregant drugs to prevent recurrence of symptoms. Clinical manifestations in Israeli patients did not differ from those in non-Israeli patients. Venous or arterial thrombosis and obstetric complications are the most frequent clinical findings in APS. There was no different in clinical manifestations between primary and secondary syndrome. The findings of autoimmune hemolytic anemia and ANA were more frequent in

  10. A novel antibody-based biomarker for chronic algal toxin exposure and sub-acute neurotoxicity

    Science.gov (United States)

    Lefebvre, Kathi A.; Frame, Elizabeth R.; Gulland, Frances; Hansen, John D.; Kendrick, Preston S.; Beyer, Richard P.; Bammler, Theo K.; Farin, Frederico M.; Hiolski, Emma M.; Smith, Donald R.; Marcinek, David J.

    2012-01-01

    The neurotoxic amino acid, domoic acid (DA), is naturally produced by marine phytoplankton and presents a significant threat to the health of marine mammals, seabirds and humans via transfer of the toxin through the foodweb. In humans, acute exposure causes a neurotoxic illness known as amnesic shellfish poisoning characterized by seizures, memory loss, coma and death. Regular monitoring for high DA levels in edible shellfish tissues has been effective in protecting human consumers from acute DA exposure. However, chronic low-level DA exposure remains a concern, particularly in coastal and tribal communities that subsistence harvest shellfish known to contain low levels of the toxin. Domoic acid exposure via consumption of planktivorous fish also has a profound health impact on California sea lions (Zalophus californianus) affecting hundreds of animals yearly. Due to increasing algal toxin exposure threats globally, there is a critical need for reliable diagnostic tests for assessing chronic DA exposure in humans and wildlife. Here we report the discovery of a novel DA-specific antibody response that is a signature of chronic low-level exposure identified initially in a zebrafish exposure model and confirmed in naturally exposed wild sea lions. Additionally, we found that chronic exposure in zebrafish caused increased neurologic sensitivity to DA, revealing that repetitive exposure to DA well below the threshold for acute behavioral toxicity has underlying neurotoxic consequences. The discovery that chronic exposure to low levels of a small, water-soluble single amino acid triggers a detectable antibody response is surprising and has profound implications for the development of diagnostic tests for exposure to other pervasive environmental toxins.

  11. Neutralization of Clostridium difficile Toxin B Mediated by Engineered Lactobacilli That Produce Single-Domain Antibodies

    Science.gov (United States)

    Andersen, Kasper Krogh; Strokappe, Nika M.; Hultberg, Anna; Truusalu, Kai; Smidt, Imbi; Mikelsaar, Raik-Hiio; Mikelsaar, Marika; Verrips, Theo; Hammarström, Lennart

    2015-01-01

    Clostridium difficile is the primary cause of nosocomial antibiotic-associated diarrhea in the Western world. The major virulence factors of C. difficile are two exotoxins, toxin A (TcdA) and toxin B (TcdB), which cause extensive colonic inflammation and epithelial damage manifested by episodes of diarrhea. In this study, we explored the basis for an oral antitoxin strategy based on engineered Lactobacillus strains expressing TcdB-neutralizing antibody fragments in the gastrointestinal tract. Variable domain of heavy chain-only (VHH) antibodies were raised in llamas by immunization with the complete TcdB toxin. Four unique VHH fragments neutralizing TcdB in vitro were isolated. When these VHH fragments were expressed in either secreted or cell wall-anchored form in Lactobacillus paracasei BL23, they were able to neutralize the cytotoxic effect of the toxin in an in vitro cell-based assay. Prophylactic treatment with a combination of two strains of engineered L. paracasei BL23 expressing two neutralizing anti-TcdB VHH fragments (VHH-B2 and VHH-G3) delayed killing in a hamster protection model where the animals were challenged with spores of a TcdA− TcdB+ strain of C. difficile (P survived until the termination of the experiment at day 5 and showed either no damage or limited inflammation of the colonic mucosa despite having been colonized with C. difficile for up to 4 days. The protective effect in the hamster model suggests that the strategy could be explored as a supplement to existing therapies for patients. PMID:26573738

  12. A simple electroelution method for rapid protein purification: isolation and antibody production of alpha toxin from Clostridium septicum

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    Lorena Vázquez-Iglesias

    2017-06-01

    Full Text Available Clostridium septicum produces a number of diseases in human and farm animals which, in most of the cases, are fatal without clinical intervention. Alpha toxin is an important agent and the unique lethal virulent factor produced by Clostridium septicum. This toxin is haemolytic, highly lethal and necrotizing activities but is being used as an antigen to develop animal vaccines. The aim of this study was to isolate the alpha toxin of Clostridium septicum and produce highly specific antibodies against it. In this work, we have developed a simple and efficient method for alpha toxin purification, based on electroelution that can be used as a time-saving method for purifying proteins. This technique avoids contamination by other proteins that could appear during other protein purification techniques such chromatography. The highly purified toxin was used to produce polyclonal antibodies. The specificity of the antibodies was tested by western blot and these antibodies can be applied to the quantitative determination of alpha toxin by slot blot.

  13. Chemical Screens Identify Drugs that Enhance or Mitigate Cellular Responses to Antibody-Toxin Fusion Proteins.

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    Antonella Antignani

    Full Text Available The intersection of small molecular weight drugs and antibody-based therapeutics is rarely studied in large scale. Both types of agents are currently part of the cancer armamentarium. However, very little is known about how to combine them in optimal ways. Immunotoxins are antibody-toxin gene fusion proteins engineered to target cancer cells via antibody binding to surface antigens. For fusion proteins derived from Pseudomonas exotoxin (PE, potency relies on the enzymatic domain of the toxin which catalyzes the ADP-ribosylation of EF2 causing inhibition of protein synthesis leading to cell death. Candidate immunotoxins have demonstrated clear value in clinical trials but generally have not been curative as single agents. Therefore we undertook three screens to discover effective combinations that could act synergistically. From the MIPE-3 library of compounds we identified various enhancers of immunotoxin action and at least one major class of inhibitor. Follow-up experiments confirmed the screening data and suggested that immunotoxins when administered with everolimus or nilotinib exhibit favorable combinatory activity and would be candidates for preclinical development. Mechanistic studies revealed that everolimus-immunotoxin combinations acted synergistically on elements of the protein synthetic machinery, including S61 kinase and 4E-BP1 of the mTORC1 pathway. Conversely, PARP inhibitors antagonized immunotoxins and also blocked the toxicity due to native ADP-ribosylating toxins. Thus, our goal of investigating a chemical library was justified based on the identification of several approved compounds that could be developed preclinically as 'enhancers' and at least one class of mitigator to be avoided.

  14. Active immunization against gonadotrophin-releasing hormone in Chinese male pigs: effects of dose on antibody titer, hormone levels and sexual development.

    Science.gov (United States)

    Zeng, Xian Y; Turkstra, Johan A; Meloen, Rob H; Liu, Xian Y; Chen, Fa Q; Schaaper, Wim M M; Oonk, H B; Guo, Da Z; van de Wiel, Dick F M

    2002-04-15

    The objective of this study was to determine the optimal dose of a GnRH vaccine for immunocastration of Chinese male pigs, based on immune, endocrine and testicular responses. Forty-two crossbred (Chinese Yanan x Large White) male pigs were randomly assigned to one of the five treatments as follows: (I) 0 microg (control, n=8); (II) 10 microg (n=8); (III) 62.5 microg (n=8); (IV) 125 microg (n=8); (V) 250 microg (n=10), D-Lys6-GnRH tandem dimer (TDK) peptide equivalent of conjugate (TDK-OVA), using Specol as the adjuvant. Pigs were immunized at 13 and 21 weeks of age and were slaughtered at 31 weeks of age. Blood samples for antibody titer and hormone assays were collected at 13, 21, 24 and 31 weeks of age. At these time-points, testis size was also measured. At slaughter, testis weight was recorded and fat samples were collected for androstenone assay. Four animals, one out of each immunized group, responded poorly to the immunization (non-responders). At slaughter, serum testosterone and LH levels, fat androstenone levels and testis size/weight of these non-responders were similar to those in control animals. Antibody titers of non-responders were substantially lower (Pimmunized pigs. For the animals that responded well to the immunization (immunocastrated pigs), serum testosterone and LH levels, fat androstenone levels and testis size or weight were reduced (Ppigs in treatments II-V was reduced to 55, 21, 33 and 25%, respectively, whereas testis weight was reduced to 39, 12, 18 and 14%, respectively. Reduction of testis size and/or weight is important for visual assessment of castration at the slaughterline, therefore, it is concluded that a dose of 10 microg peptide is not suitable. We conclude that, within the dose-range studied, the 62.5 microg dose is optimal for future GnRH immunization studies or future practical use in immunocastration of Chinese male pigs.

  15. Effect of ambient temperature on viral replication and serum antibody titers following administration of a commercial intranasal modified-live infectious bovine rhinotracheitis-parainfluenza-3 virus vaccine to beef cattle housed in high- and moderate-ambient temperature environments.

    Science.gov (United States)

    Grissett, Gretchen P; White, Brad J; Anderson, David E; Larson, Robert E; Miesner, Matt D

    2014-12-01

    To evaluate the effect of ambient temperature on viral replication and serum antibody titers following administration of an intranasal modified-live infectious bovine rhinotracheitis (IBR)-parainfluenza-3 (PI3) virus vaccine to beef calves housed in high- (> 32°C) and moderate- (21°C) ambient temperature environments. 28 calves (mean weight, 206.8 kg). Calves were randomly allocated to 4 treatment groups (housed outdoors during high ambient temperature with [HAT; n = 10] or without [HAC; 4] vaccination or housed indoors in a moderate ambient temperature with [MAT; 10] or without [MAC; 4] vaccination). Rectal and nasal mucosal temperatures were recorded every 2 hours from 8 AM to 8 PM on days 0 (vaccination) and 1. Nasal swab specimens were obtained on days 0 through 7 for virus isolation. Serum samples were collected on days 0, 7, 14, and 28 for determination of antibody titers. Mean rectal temperature did not differ among the treatment groups. Mean nasal temperature for the HAT group was significantly higher than that for the MAT group at 6, 24, 30, 32, and 38 hours after vaccination. Viable IBR virus was isolated from all vaccinated calves on days 1 through 6. Two weeks after vaccination, vaccinated calves had anti-IBR antibody titers that were significantly greater than those for unvaccinated calves. Mean anti-IBR antibody titers did not differ significantly between the HAT and MAT groups. Results indicated that, following vaccination with an intranasal modified-live IBR-PI3 virus vaccine, IBR viral replication and serum antibody titers did not differ significantly between calves housed in high- and moderate-ambient temperature environments.

  16. Screening for single-chain variable fragment antibodies against multiple Cry1 toxins from an immunized mouse phage display antibody library.

    Science.gov (United States)

    Dong, Sa; Bo, Zongyi; Zhang, Cunzheng; Feng, Jianguo; Liu, Xianjin

    2018-04-01

    Single-chain variable fragment (scFv) is a kind of antibody that possess only one chain of the complete antibody while maintaining the antigen-specific binding abilities and can be expressed in prokaryotic system. In this study, scFvs against Cry1 toxins were screened out from an immunized mouse phage displayed antibody library, which was successfully constructed with capacity of 6.25 × 10 7  CFU/mL. Using the mixed and alternative antigen coating strategy and after four rounds of affinity screening, seven positive phage-scFvs against Cry1 toxins were selected and characterized. Among them, clone scFv-3H9 (MG214869) showing relative stable and high binding abilities to six Cry1 toxins was selected for expression and purification. SDS-PAGE indicated that the scFv-3H9 fragments approximately 27 kDa were successfully expressed in Escherichia coli HB2151 strain. The purified scFv-3H9 was used to establish the double antibody sandwich enzyme-linked immunosorbent assay method (DAS-ELISA) for detecting six Cry1 toxins, of which the lowest detectable limits (LOD) and the lowest quantitative limits (LOQ) were 3.14-11.07 and 8.22-39.44 ng mL -1 , respectively, with the correlation coefficient higher than 0.997. The average recoveries of Cry1 toxins from spiked rice leaf samples were ranged from 84 to 95%, with coefficient of variation (CV) less than 8.2%, showing good accuracy for the multi-residue determination of six Cry1 toxins in agricultural samples. This research suggested that the constructed phage display antibody library based on the animal which was immunized with the mixture of several antigens under the same category can be used for the quick and effective screening of generic antibodies.

  17. Potency of a human monoclonal antibody to diphtheria toxin relative to equine diphtheria anti-toxin in a guinea pig intoxication model.

    Science.gov (United States)

    Smith, Heidi L; Cheslock, Peter; Leney, Mark; Barton, Bruce; Molrine, Deborah C

    2016-08-17

    Prompt administration of anti-toxin reduces mortality following Corynebacterium diphtheriae infection. Current treatment relies upon equine diphtheria anti-toxin (DAT), with a 10% risk of serum sickness and rarely anaphylaxis. The global DAT supply is extremely limited; most manufacturers have ceased production. S315 is a neutralizing human IgG1 monoclonal antibody to diphtheria toxin that may provide a safe and effective alternative to equine DAT and address critical supply issues. To guide dose selection for IND-enabling pharmacology and toxicology studies, we dose-ranged S315 and DAT in a guinea pig model of diphtheria intoxication based on the NIH Minimum Requirements potency assay. Animals received a single injection of antibody premixed with toxin, were monitored for 30 days, and assigned a numeric score for clinical signs of disease. Animals receiving ≥ 27.5 µg of S315 or ≥ 1.75 IU of DAT survived whereas animals receiving ≤ 22.5 µg of S315 or ≤ 1.25 IU of DAT died, yielding a potency estimate of 17 µg S315/IU DAT (95% CI 16-21) for an endpoint of survival. Because some surviving animals exhibited transient limb weakness, likely a systemic sign of toxicity, DAT and S315 doses required to prevent hind limb paralysis were also determined, yielding a relative potency of 48 µg/IU (95% CI 38-59) for this alternate endpoint. To support advancement of S315 into clinical trials, potency estimates will be used to evaluate the efficacy of S315 versus DAT in an animal model with antibody administration after toxin exposure, more closely modeling anti-toxin therapy in humans.

  18. Review for the generalist: The antinuclear antibody test in children - When to use it and what to do with a positive titer

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    Sailer-Hoeck Michaela

    2010-10-01

    Full Text Available Abstract The antinuclear antibody test (ANA is a much overused test in pediatrics. The ANA does have a role in serologic testing but it should be a very limited one. It is often ordered as a screening test for rheumatic illnesses in a primary care setting. However, since it has low specificity and sensitivity for most rheumatic and musculoskeletal illnesses in children, it should not be ordered as a screening test for non-specific complaints such as musculoskeletal pain. It should only be used as a diagnostic test for children with probable Systemic Lupus Erythematosus (SLE or Mixed Connective Tissue Disease, (MCTD and other possible overlap-like illnesses. Such children should have developed definite signs and symptoms of a disease before the ANA is ordered. This review presents data supporting these conclusions and a review of the ANA literature in adults and children. By limiting ANA testing, primary care providers can avoid needless venipuncture pain, unnecessary referrals, extra medical expenses, and most importantly, significant parental anxieties. It is best not to do the ANA test in most children but if it ordered and is positive in a low titer (

  19. Stimulation of cAMP levels and modulation of antibody formation in mice immunized with cholera toxin. [Vibrio cholerae

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    Kateley, J.R.; Friedman, H.

    1975-02-28

    Injection of mice with 1.0 ..mu..g of a purified exotoxin derived from Vibrio cholerae together with a challenge injection of sheep erythrocytes (SRBC) or E. coli LPS markedly influenced the immune response to these antigens. Simultaneous injection of the toxin with antigen resulted in a delayed appearance of antibody-forming cells during the first few days after immunization, followed by a marked enhancement of the peak numbers of antibody-forming cells. In the case of the immune response to SRBC, both 19S and 7S plaque-forming cells (PFC) were enhanced on the peak day of response after simultaneous immunization of toxin-injected mice. The secondary immune response to SRBC was also similarly affected when cholera toxin was given along with a second injection of erythrocytes; i.e., a delay in appearance of the first antibody-forming cells followed by a marked enhancement of the peak 19S and 7S PFC response. Injection of cholera toxin 1-3 days prior to SRBC or LPS was immunosuppressive. The effect of cholera toxin on the level of splenic cyclic AMP appeared related to the effects on antibody formation.

  20. Expression of Receptors for Tetanus Toxin and Monoclonal Antibody A2B5 by Pancreatic Islet Cells

    Science.gov (United States)

    Eisenbarth, G. S.; Shimizu, K.; Bowring, M. A.; Wells, S.

    1982-08-01

    Studies of the reaction of antibody A2B5 and tetanus toxin with pancreatic islet cells, islet cell tumors, and other human amine precursor uptake and decarboxylation (APUD) tumors are described. By indirect immunofluorescence, antibody A2B5 and tetanus toxin were shown to specifically bind to the plasma membrane of human, rat, chicken, and mouse islet cells. The binding of antibody A2B5 to the cell surface of living islet cells has allowed isolation of these cells from a suspension of pancreatic cells by using a fluorescence-activated cell sorter. In studies designed to determine whether tetanus toxin and antibody A2B5 bound to the same surface antigen, A2B5 and tetanus toxin did not compete for binding to normal islet cells, a human islet cell tumor, or a rat islet cell tumor. In addition to binding to islet cell tumors, antibody A2B5 reacts with frozen sections, isolated cells, and cell lines of neural, neural crest, and APUD origin.

  1. Antibody response of growing German Holstein bulls to a vaccination against bovine viral diarrhea virus (BVDV) is influenced by Fusarium toxin exposure in a non-linear fashion.

    Science.gov (United States)

    Dänicke, Sven; Winkler, Janine; Meyer, Ulrich; Kersten, Susanne; Wernike, Kerstin; Beer, Martin; Frahm, Jana

    2018-05-01

    The Fusarium toxin deoxynivalenol (DON) is a frequent contaminant of feedstuffs and is supposed to interfere with immune responses. As the relevance for growing bulls is less clear than for other livestock, the trial was designed according to the dose-response principal with a control group fed a diet with background contamination (CON, 0.36 mg DON per kilogram dry matter [DM]) and three groups with increasing concentrations of DON (mg/kg DM); FUS I, 3.01; FUS II, 5.66; FUS III, 8.31. Half of each treatment group was vaccinated against BVDV at days 1 and 21 of the 70 days lasting experiment. Sequential blood samples were collected for determination of antibody titers to BVDV and for hematological and clinical-chemical traits. Antibody response was strongest in group FUS II while group FUS III responded weakest. This group showed the lowest proportion of CD4+ T cells, but also the highest levels of liver lesion indicating enzyme activities in blood. BVDV-vaccination induced a pronounced decrease in red blood count indices, which occurred dose-dependently at a higher level in the FUS-fed groups. The obvious interactions between DON exposure and BVDV-vaccination require further elucidation.

  2. [Rabies virus antibody titers in dogs in Campo Grande, Mato Grosso do Sul State, during the anti-rabies campaign, 2003].

    Science.gov (United States)

    Rigo, Leonardo; Honer, Michael Robin

    2006-01-01

    To assess the immune response in dogs attended during the 2003 anti-rabies animal vaccination campaign, 333 serum samples collected at different vaccination posts were analyzed. It was found that 51.1% of the animals did not have protective titers. No correlation was found between vaccine application or multiple vaccinations and higher immune titers.

  3. Pichia pastoris-expressed dengue 2 envelope forms virus-like particles without pre-membrane protein and induces high titer neutralizing antibodies.

    Science.gov (United States)

    Mani, Shailendra; Tripathi, Lav; Raut, Rajendra; Tyagi, Poornima; Arora, Upasana; Barman, Tarani; Sood, Ruchi; Galav, Alka; Wahala, Wahala; de Silva, Aravinda; Swaminathan, Sathyamangalam; Khanna, Navin

    2013-01-01

    Dengue is a mosquito-borne viral disease with a global prevalence. It is caused by four closely-related dengue viruses (DENVs 1-4). A dengue vaccine that can protect against all four viruses is an unmet public health need. Live attenuated vaccine development efforts have encountered unexpected interactions between the vaccine viruses, raising safety concerns. This has emphasized the need to explore non-replicating dengue vaccine options. Virus-like particles (VLPs) which can elicit robust immunity in the absence of infection offer potential promise for the development of non-replicating dengue vaccine alternatives. We have used the methylotrophic yeast Pichia pastoris to develop DENV envelope (E) protein-based VLPs. We designed a synthetic codon-optimized gene, encoding the N-terminal 395 amino acid residues of the DENV-2 E protein. It also included 5' pre-membrane-derived signal peptide-encoding sequences to ensure proper translational processing, and 3' 6× His tag-encoding sequences to facilitate purification of the expressed protein. This gene was integrated into the genome of P. pastoris host and expressed under the alcohol oxidase 1 promoter by methanol induction. Recombinant DENV-2 protein, which was present in the insoluble membrane fraction, was extracted and purified using Ni(2+)-affinity chromatography under denaturing conditions. Amino terminal sequencing and detection of glycosylation indicated that DENV-2 E had undergone proper post-translational processing. Electron microscopy revealed the presence of discrete VLPs in the purified protein preparation after dialysis. The E protein present in these VLPs was recognized by two different conformation-sensitive monoclonal antibodies. Low doses of DENV-2 E VLPs formulated in alum were immunogenic in inbred and outbred mice eliciting virus neutralizing titers >1,1200 in flow cytometry based assays and protected AG129 mice against lethal challenge (pdengue vaccine.

  4. Rapid O serogroup identification of the six clinically relevant Shiga toxin-producing Escherichia coli by antibody microarray

    Science.gov (United States)

    Antibody array was developed for the detection of the top six non-O157 Shiga toxin-producing Escherichia coli O serogroups. Sensitivity of the array was 10**5 CFU, and the limit of detection of serogroups in ground beef was 1-10 CFU following 12 h of enrichment. The array utilized a minimal amount...

  5. Mouse in Vivo Neutralization of Escherichia coli Shiga Toxin 2 with Monoclonal Antibodies

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    Larry H. Stanker

    2013-10-01

    Full Text Available Shiga toxin-producing Escherichia coli (STEC food contaminations pose serious health concerns, and have been the subject of massive food recalls. STEC has been identified as the major cause of the life-threatening complication of hemolytic uremic syndrome (HUS. Besides supportive care, there currently are no therapeutics available. The use of antibiotics for combating pathogenic E. coli is not recommended because they have been shown to stimulate toxin production. Clearing Stx2 from the circulation could potentially lessen disease severity. In this study, we tested the in vivo neutralization of Stx2 in mice using monoclonal antibodies (mAbs. We measured the biologic half-life of Stx2 in mice and determined the distribution phase or t1/2 α to be 3 min and the clearance phase or t1/2 β to be 40 min. Neutralizing mAbs were capable of clearing Stx2 completely from intoxicated mouse blood within minutes. We also examined the persistence of these mAbs over time and showed that complete protection could be passively conferred to mice 4 weeks before exposure to Stx2. The advent of better diagnositic methods and the availability of a greater arsenal of therapeutic mAbs against Stx2 would greatly enhance treatment outcomes of life threatening E. coli infections.

  6. Títulos de anticorpos aglutinantes induzidos por vacinas comerciais contra leptospirose bovina Agglutinating antibody titers induced by commercial vaccines against bovine leptospirosis

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    Gabriela de Godoy Cravo Arduino

    2009-07-01

    serovars. All vaccines used were capable to product agglutinins for the Hardjo and Wolffi serovars observed at 3 days after vaccination, remaining until the 150th day; those serovars induced the highest titres of agglutinins. Vaccine D, in spite of not containing the Wolffi serovar, induced the production of agglutinins to this serovar. Agglutinins to the Canicola serovar were only observed in the animals vaccinated with the D bacterine. Vaccine D induced the highest average titers of antibodies to all tested serovars.

  7. Differential neutralizing activities of a single domain camelid antibody (VHH specific for ricin toxin's binding subunit (RTB.

    Directory of Open Access Journals (Sweden)

    Cristina Herrera

    Full Text Available Ricin, a member of the A-B family of ribosome-inactivating proteins, is classified as a Select Toxin by the Centers for Disease Control and Prevention because of its potential use as a biothreat agent. In an effort to engineer therapeutics for ricin, we recently produced a collection of alpaca-derived, heavy-chain only antibody VH domains (VHH or "nanobody" specific for ricin's enzymatic (RTA and binding (RTB subunits. We reported that one particular RTB-specific VHH, RTB-B7, when covalently linked via a peptide spacer to different RTA-specific VHHs, resulted in heterodimers like VHH D10/B7 that were capable of passively protecting mice against a lethal dose challenge with ricin. However, RTB-B7 itself, when mixed with ricin at a 1 ∶ 10 toxin:antibody ratio did not afford any protection in vivo, even though it had demonstrable toxin-neutralizing activity in vitro. To better define the specific attributes of antibodies associated with ricin neutralization in vitro and in vivo, we undertook a more thorough characterization of RTB-B7. We report that RTB-B7, even at 100-fold molar excess (toxin:antibody was unable to alter the toxicity of ricin in a mouse model. On the other hand, in two well-established cytotoxicity assays, RTB-B7 neutralized ricin with a 50% inhibitory concentration (IC50 that was equivalent to that of 24B11, a well-characterized and potent RTB-specific murine monoclonal antibody. In fact, RTB-B7 and 24B11 were virtually identical when compared across a series of in vitro assays, including adherence to and neutralization of ricin after the toxin was pre-bound to cell surface receptors. RTB-B7 differed from both 24B11 and VHH D10/B7 in that it was relatively less effective at blocking ricin attachment to receptors on host cells and was not able to form high molecular weight toxin:antibody complexes in solution. Whether either of these activities is important in ricin toxin neutralizing activity in vivo remains to be determined.

  8. Pichia pastoris-expressed dengue 2 envelope forms virus-like particles without pre-membrane protein and induces high titer neutralizing antibodies.

    Directory of Open Access Journals (Sweden)

    Shailendra Mani

    Full Text Available Dengue is a mosquito-borne viral disease with a global prevalence. It is caused by four closely-related dengue viruses (DENVs 1-4. A dengue vaccine that can protect against all four viruses is an unmet public health need. Live attenuated vaccine development efforts have encountered unexpected interactions between the vaccine viruses, raising safety concerns. This has emphasized the need to explore non-replicating dengue vaccine options. Virus-like particles (VLPs which can elicit robust immunity in the absence of infection offer potential promise for the development of non-replicating dengue vaccine alternatives. We have used the methylotrophic yeast Pichia pastoris to develop DENV envelope (E protein-based VLPs. We designed a synthetic codon-optimized gene, encoding the N-terminal 395 amino acid residues of the DENV-2 E protein. It also included 5' pre-membrane-derived signal peptide-encoding sequences to ensure proper translational processing, and 3' 6× His tag-encoding sequences to facilitate purification of the expressed protein. This gene was integrated into the genome of P. pastoris host and expressed under the alcohol oxidase 1 promoter by methanol induction. Recombinant DENV-2 protein, which was present in the insoluble membrane fraction, was extracted and purified using Ni(2+-affinity chromatography under denaturing conditions. Amino terminal sequencing and detection of glycosylation indicated that DENV-2 E had undergone proper post-translational processing. Electron microscopy revealed the presence of discrete VLPs in the purified protein preparation after dialysis. The E protein present in these VLPs was recognized by two different conformation-sensitive monoclonal antibodies. Low doses of DENV-2 E VLPs formulated in alum were immunogenic in inbred and outbred mice eliciting virus neutralizing titers >1,1200 in flow cytometry based assays and protected AG129 mice against lethal challenge (p<0.05. The formation of immunogenic DENV-2 E

  9. The seroepidemiology of Immunoglobulin G antibodies against pertussis toxin in China: a cross sectional study

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    Zhang Qi

    2012-06-01

    Full Text Available Abstract Background Pertussis is a reported vaccine-preventable respiratory disease in China. Because the routine laboratory methods for diagnosis are not in use, the reported cases are mainly in infants with classical paroxysmal cough and the true incidence related to pertussis is most likely under estimated. In China, however, few studies have attempted to address this issue. The purpose of this cross sectional study was to estimate the incidence rates using the method of sero-epidemiology of immunoglobulin (Ig G antibodies against pertussis toxin (PT among healthy populations in China. Methods Blood samples were obtained from 1313 healthy individuals aged 0 to 95 years in Guangdong province of China throughout September 2010. Serum IgG antibodies against PT were determined by commercial ELISA kits. Subjects with concentration of anti-PT IgG higher than 30 IU/mL were indicated to have recent Bordetella pertussis infection, if they have not received a booster dose of pertussis vaccine within one year. Results Of the 1313 study subjects, 117 (8.91% were found to have anti-PT antibodies higher than 30 IU/mL. The estimated incidence of recent infection was thus 9395 per 100,000 for individuals older than 7 years. Peaks of the estimated incidence rate of recent infection were found to be 11561 per 100,000 in age group of 41–50 years and 11428 per 100,000 in the group aged 13–19 years. Conclusions Our study indicated that B.pertussis infections are considerablely common, particularly in adolescents and adults in China. The study also stresses the importance of laboratory diagnosis for pertussis and employment of booster dose of pertussis vaccine in adolescents and adults in this country.

  10. Ameliorative effect of a microbial feed additive on infectious bronchitis virus antibody titer and stress index in broiler chicks fed deoxynivalenol.

    Science.gov (United States)

    Ghareeb, K; Awad, W A; Böhm, J

    2012-04-01

    Although acute mycotoxicoses are rare in poultry production, chronic exposure to low levels of mycotoxins is responsible for reduced productivity and increased susceptibility to infectious diseases. Deoxynivalenol (DON) is known to modulate immune function, but only a few studies have investigated the effect of DON on the vaccinal immune response. In addition, the effects of Mycofix select (Biomin GmbH, Herzogenburg, Austria) supplementation to DON-contaminated broiler diets have not yet been demonstrated. Therefore, an experiment with 1-d-old male broilers (Ross 308) was carried out to examine the effects of feeding DON-contaminated low-protein grower diets on performance, serum biochemical parameters, lymphoid organ weight, and antibody titers to infectious bronchitis vaccination in serum and to evaluate the effects of Mycofix select dietary supplementation in either the presence or absence of DON in broilers. In total, thirty-two 1-d-old broiler chicks were randomly assigned to 1 of the 4 dietary treatments for 5 wk. The dietary treatments were 1) control; 2) artificially contaminated diets with 10 mg of DON/kg of diet; 3) DON-contaminated diets supplemented with Mycofix select; and 4) control diet supplemented with Mycofix select. Feeding of contaminated diets decreased (P = 0.000) the feed intake, BW (P = 0.001), BW gain (P = 0.044), and feed efficiency during the grower phase. Deoxynivalenol affected the blood biochemistry, whereas plasma total protein and uric acid concentrations in birds fed contaminated grains were decreased compared with those of the controls. Moreover, in birds fed contaminated feeds, there was a tendency to reduce triglycerides in the plasma (P = 0.090), suggesting that DON in the diets affected protein and lipid metabolism in broiler chickens. The feeding of contaminated diets altered the immune response in broilers by reducing the total lymphocyte count. Similarly, the antibody response against infectious bronchitis vaccination

  11. Antistreptolysin O titer

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003522.htm Antistreptolysin O titer To use the sharing features on this page, please enable JavaScript. Antistreptolysin O (ASO) titer is a blood test to measure ...

  12. SURVEI TITER ANTI BODI ANAK SEKOLAH USIA 6--17 TAHUN DI DAERAH KLB DIFTERI DAN NON KLB DI INDONESIA

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    Noer Endah Pracoyo

    2014-02-01

    Full Text Available AbstractDiphtheriae  is an  reemerging infectious disease  widespread in the world. Bacterial infection of Corynebacterium diphtheria usually not invasive, but the bacteria can produce toxins that cause pathological effects on the heart muscle and other organs, and a 10-17% death-risk was occurred.  Diphtheriae can be prevented by immunization.  Immunizations are given to infants at the age of 0-11 months and procead to booster for pupils at Elementary School. The imunization program at school is a routinely cunducted. Such program held annualy on certain month that called as “BIAS pupils immunization month” . To examine antibody  titer of diphtheriae, research for sero  survey titer antibody titer of diphtheriae was conducted on pupils between 6 and 17 years old at outbreak areas and non outbreak area.The research started in May 2010 and finished in Desember 2010. The aim of the research was to measure the antibody titer in area of outbreak and non outbreak of school children. Design was case control study. Sera of the respondens were axamined by Elisa for detecting antibody titers against diphtheriae. The study awarded ethical clearence from Research Ethics Committee of the National Institute of Health Research and Developmnent. Number of sample cases were 225 samples and 225 control. Analysis of the data by using the soft ware (SPSS 16.00. The result of this research were respondens who lived in the outbreak area with risk of dipthteriae infection of 2,3 times than respondens who lived in the non outbreak area. The immunization of diphthteriae more important for antibody titers.Keywords: Antibody titer diphtheriae, outbreak areaAbstrakDifteria adalah  penyakit infeksi Reemerging tersebar luas di dunia. Infeksi kuman Corynebacterium diphtheria  biasanya tidak invasif, tetapi kuman dapat memproduksi toksin yang dapat menimbulkan efek patologis pada otot jantung dan organ lain, dan berisiko terjadi kematian (10-17%. Difteri dapat

  13. [In vitro immunization for the production of antibodies to tetanus toxin and toxoid. 1. Systems for the detection of in vitro synthetized specific immunoglobulins. Strategies of test development].

    Science.gov (United States)

    Kiessig, S T; Jahn, S; Porstmann, T; von Baehr, R

    1987-01-01

    By means of semipurified tetanus toxin for solid phase coating in an enzyme immunoassay (ELISA) for detection of specific IgG and IgM antibodies a detection limit of 0.02 IU per litre was achieved. The addition of serum from animals like horses or goats as inert protein to the dilution medium was omitted to prevent a displacement of human antibodies by antitetanus antibodies present in the animals sera. The specificity of the ELISA was demonstrated by inhibition experiments with soluble antigen and in an ELISA for detection of anti-tetanus toxin antibodies from mice immunized with the toxoid from the different purification steps.

  14. Isolation of anti-toxin single domain antibodies from a semi-synthetic spiny dogfish shark display library

    Directory of Open Access Journals (Sweden)

    Goldman Ellen R

    2007-11-01

    Full Text Available Abstract Background Shark heavy chain antibody, also called new antigen receptor (NAR, consists of one single Variable domain (VH, containing only two complementarity-determining regions (CDRs. The antigen binding affinity and specificity are mainly determined by these two CDRs. The good solubility, excellent thermal stability and complex sequence variation of small single domain antibodies (sdAbs make them attractive alternatives to conventional antibodies. In this report, we construct and characterize a diversity enhanced semi-synthetic NAR V display library based on naturally occurring NAR V sequences. Results A semi-synthetic shark sdAb display library with a complexity close to 1e9 was constructed. This was achieved by introducing size and sequence variations in CDR3 using randomized CDR3 primers of three different lengths. Binders against three toxins, staphylococcal enterotoxin B (SEB, ricin, and botulinum toxin A (BoNT/A complex toxoid, were isolated from panning the display library. Soluble sdAbs from selected binders were purified and evaluated using direct binding and thermal stability assays on the Luminex 100. In addition, sandwich assays using sdAb as the reporter element were developed to demonstrate their utility for future sensor applications. Conclusion We demonstrated the utility of a newly created hyper diversified shark NAR displayed library to serve as a source of thermal stable sdAbs against a variety of toxins.

  15. Individuals with selective IgA deficiency resolve rotavirus disease and develop higher antibody titers (IgG, IgG1) than IgA competent individuals.

    Science.gov (United States)

    Istrate, Claudia; Hinkula, Jorma; Hammarström, Lennart; Svensson, Lennart

    2008-03-01

    While IgA is proposed to be essential to control rotavirus disease, no information is available how IgA deficient individuals modulate rotavirus disease and immune responses. In this study it was shown that patients (n = 62) with selective IgA deficiency (IgA-D) (IgA proficient individuals (n = 62) (geometric mean titer, GMT) 18,101 vs. 4,000 (P IgA is not essential for resolving rotavirus disease in humans.

  16. Antibodies derived from a toxoid MEFA (multiepitope fusion antigen) show neutralizing activities against heat-labile toxin (LT), heat-stable toxins (STa, STb), and Shiga toxin 2e (Stx2e) of porcine enterotoxigenic Escherichia coli (ETEC).

    Science.gov (United States)

    Rausch, Dana; Ruan, Xiaosai; Nandre, Rahul; Duan, Qiangde; Hashish, Emad; Casey, Thomas A; Zhang, Weiping

    2017-04-01

    Enterotoxigenic Escherichia coli (ETEC) strains are the main cause of diarrhea in pigs. Pig diarrhea especially post-weaning diarrhea remains one of the most important swine diseases. ETEC bacterial fimbriae including K88, F18, 987P, K99 and F41 promote bacterial attachment to intestinal epithelial cells and facilitate ETEC colonization in pig small intestine. ETEC enterotoxins including heat-labile toxin (LT) and heat-stable toxins type Ia (porcine-type STa) and type II (STb) stimulate fluid hyper-secretion, leading to watery diarrhea. Blocking bacteria colonization and/or neutralizing enterotoxicity of ETEC toxins are considered effective prevention against ETEC diarrhea. In this study, we applied the MEFA (multiepitope fusion antigen) strategy to create toxoid MEFAs that carried antigenic elements of ETEC toxins, and examined for broad antitoxin immunogenicity in a murine model. By embedding STa toxoid STa P12F (NTFYCCELCCNFACAGCY), a STb epitope (KKDLCEHY), and an epitope of Stx2e A subunit (QSYVSSLN) into the A1 peptide of a monomeric LT toxoid (LT R192G ), two toxoid MEFAs, 'LT R192G -STb-Stx2e-STa P12F ' and 'LT R192G -STb-Stx2e-3xSTa P12F ' which carried three copies of STa P12F , were constructed. Mice intraperitoneally immunized with each toxoid MEFA developed IgG antibodies to all four toxins. Induced antibodies showed in vitro neutralizing activities against LT, STa, STb and Stx2e toxins. Moreover, suckling piglets born by a gilt immunized with 'LT R192G -STb-Stx2e-3xSTa P12F ' were protected when challenged with ETEC strains, whereas piglets born by a control gilt developed diarrhea. Results from this study showed that the toxoid MEFA induced broadly antitoxin antibodies, and suggested potential application of the toxoid MEFA for developing a broad-spectrum vaccine against ETEC diarrhea in pigs. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. A cocktail of humanized anti-pertussis toxin antibodies limits disease in murine and baboon models of whooping cough.

    Science.gov (United States)

    Nguyen, Annalee W; Wagner, Ellen K; Laber, Joshua R; Goodfield, Laura L; Smallridge, William E; Harvill, Eric T; Papin, James F; Wolf, Roman F; Padlan, Eduardo A; Bristol, Andy; Kaleko, Michael; Maynard, Jennifer A

    2015-12-02

    Despite widespread vaccination, pertussis rates are rising in industrialized countries and remain high worldwide. With no specific therapeutics to treat disease, pertussis continues to cause considerable infant morbidity and mortality. The pertussis toxin is a major contributor to disease, responsible for local and systemic effects including leukocytosis and immunosuppression. We humanized two murine monoclonal antibodies that neutralize pertussis toxin and expressed them as human immunoglobulin G1 molecules with no loss of affinity or in vitro neutralization activity. When administered prophylactically to mice as a binary cocktail, antibody treatment completely mitigated the Bordetella pertussis-induced rise in white blood cell counts and decreased bacterial colonization. When administered therapeutically to baboons, antibody-treated, but not untreated control animals, experienced a blunted rise in white blood cell counts and accelerated bacterial clearance rates. These preliminary findings support further investigation into the use of these antibodies to treat human neonatal pertussis in conjunction with antibiotics and supportive care. Copyright © 2015, American Association for the Advancement of Science.

  18. Low titer, isolated anti Ro/SSA 60 kd antibodies is correlated with positive pregnancy outcomes in women at risk of congenital heart block.

    Science.gov (United States)

    Tonello, Marta; Hoxha, Ariela; Mattia, Elena; Zambon, Alessandra; Visentin, Silvia; Cerutti, Alessia; Ghirardello, Anna; Milanesi, Ornella; Ruffatti, Amelia

    2017-05-01

    Congenital heart block (CHB) is an autoantibody mediated disorder presumably caused by placental transmission of maternal autoantibodies to Ro/SSA 52 kd, p200, Ro/SSA 60 kd, La/SSB ribonucleoproteins. This study investigated the clinical significance of isolated anti-Ro/SSA 52 kd, anti-p200, anti-Ro/SSA 60 kd, and anti-La/SSB antibodies in positive pregnant patients. One hundred sixty-three pregnant women positive to anti-Ro/SSA 52 kd and/or anti-Ro/SSA 60 kd and/or anti-La/SSB antibodies were prospectively enrolled in the study. Anti-Ro52, anti-Ro60, anti-p200, and anti-La antibodies were assayed using home-made ELISA assays. Isolated antibody positivity was found in 25 women (15.3%), while multiple antibody positivity in 138 (84.7%). Twenty-four developed CHB, and the 139 had a favorable pregnancy outcome. The prevalence of isolated anti-Ro/SSA 60 kd antibodies was significantly higher (p Ro/SSA 60 kd antibodies.

  19. Measles virus antibody responses in children randomly assigned to receive standard-titer edmonston-zagreb measles vaccine at 4.5 and 9 months of age, 9 months of age, or 9 and 18 months of age

    DEFF Research Database (Denmark)

    Martins, Cesario; Garly, May-Lill; Bale, Carlitos

    2014-01-01

    The World Health Organization recommends administration of measles vaccine (MV) at age 9 months in low-income countries. We tested the measles virus antibody response at 4.5, 9, 18, and 24 months of age for children randomly assigned to receive standard-titer Edmonston-Zagreb MV at 4.5 and 9 months......, at 9 months, or at 9 and 18 months of age. At 4.5 months of age, 75% had nonprotective measles virus antibody levels. Following receipt of MV at 4.5 months of age, 77% (316/408) had protective antibody levels at 9 months of age; after a second dose at 9 months of age, 97% (326/337) had protective...... than in the group that received MV at 9 months of age (P = .0001). In conclusion, an early 2-dose MV schedule was associated with protective measles virus antibody levels at 24 months of age in nearly all children. Clinical Trials Registration. NCT00168558....

  20. DNA vaccine molecular adjuvants SP-D-BAFF and SP-D-APRIL enhance anti-gp120 immune response and increase HIV-1 neutralizing antibody titers.

    Science.gov (United States)

    Gupta, Sachin; Clark, Emily S; Termini, James M; Boucher, Justin; Kanagavelu, Saravana; LeBranche, Celia C; Abraham, Sakhi; Montefiori, David C; Khan, Wasif N; Stone, Geoffrey W

    2015-04-01

    Broadly neutralizing antibodies (bNAbs) specific for conserved epitopes on the HIV-1 envelope (Env) are believed to be essential for protection against multiple HIV-1 clades. However, vaccines capable of stimulating the production of bNAbs remain a major challenge. Given that polyreactivity and autoreactivity are considered important characteristics of anti-HIV bNAbs, we designed an HIV vaccine incorporating the molecular adjuvants BAFF (B cell activating factor) and APRIL (a proliferation-inducing ligand) with the potential to facilitate the maturation of polyreactive and autoreactive B cells as well as to enhance the affinity and/or avidity of Env-specific antibodies. We designed recombinant DNA plasmids encoding soluble multitrimers of BAFF and APRIL using surfactant protein D as a scaffold, and we vaccinated mice with these molecular adjuvants using DNA and DNA-protein vaccination strategies. We found that immunization of mice with a DNA vaccine encoding BAFF or APRIL multitrimers, together with interleukin 12 (IL-12) and membrane-bound HIV-1 Env gp140, induced neutralizing antibodies against tier 1 and tier 2 (vaccine strain) viruses. The APRIL-containing vaccine was particularly effective at generating tier 2 neutralizing antibodies following a protein boost. These BAFF and APRIL effects coincided with an enhanced germinal center (GC) reaction, increased anti-gp120 antibody-secreting cells, and increased anti-gp120 functional avidity. Notably, BAFF and APRIL did not cause indiscriminate B cell expansion or an increase in total IgG. We propose that BAFF and APRIL multitrimers are promising molecular adjuvants for vaccines designed to induce bNAbs against HIV-1. Recent identification of antibodies that neutralize most HIV-1 strains has revived hopes and efforts to create novel vaccines that can effectively stimulate HIV-1 neutralizing antibodies. However, the multiple immune evasion properties of HIV have hampered these efforts. These include the instability of

  1. Immunoglobulin with High-Titer In Vitro Cross-Neutralizing Hepatitis C Virus Antibodies Passively Protects Chimpanzees from Homologous, but Not Heterologous, Challenge

    DEFF Research Database (Denmark)

    Bukh, Jens; Engle, Ronald E.; Faulk, Kristina

    2015-01-01

    The importance of neutralizing antibodies (NAbs) in protection against hepatitis C virus (HCV) remains controversial. We infused a chimpanzee with H06 immunoglobulin from a genotype 1a HCV-infected patient and challenged with genotype strains efficiently neutralized by H06 in vitro. Genotype 1a...

  2. Patients with humoral primary immunodeficiency do not develop protective anti-influenza antibody titers after vaccination with trivalent subunit influenza vaccine

    NARCIS (Netherlands)

    van Assen, Sander; Holvast, Albert; Telgt, Denise S.C.; Benne, Cornelis A.; de Haan, Aalzen; Westra, Johanna; Kallenberg, Cornelis; Bijl, Marc

    Yearly influenza vaccination is recommended for patients with humoral primary immunodeficiency (hPID). However, humoral responses following vaccination can be expected to be reduced in these patients.The efficacy of influenza vaccination in patients with hPID, anti-influenza antibody responses was

  3. Replicating Rather than Nonreplicating Adenovirus-Human Immunodeficiency Virus Recombinant Vaccines Are Better at Eliciting Potent Cellular Immunity and Priming High-Titer Antibodies

    OpenAIRE

    Peng, Bo; Wang, Liqun Rejean; Gómez-Román, Victor Raúl; Davis-Warren, Alberta; Montefiori, David C.; Kalyanaraman, V. S.; Venzon, David; Zhao, Jun; Kan, Elaine; Rowell, Thomas J.; Murthy, Krishna K.; Srivastava, Indresh; Barnett, Susan W.; Robert-Guroff, Marjorie

    2005-01-01

    A major challenge in combating the human immunodeficiency virus (HIV) epidemic is the development of vaccines capable of inducing potent, persistent cellular immunity and broadly reactive neutralizing antibody responses to HIV type 1 (HIV-1). We report here the results of a preclinical trial using the chimpanzee model to investigate a combination vaccine strategy involving sequential priming immunizations with different serotypes of adenovirus (Ad)/HIV-1MNenv/rev recombinants and boosting wit...

  4. Effect of adding crushed Pimpinella anisum, Nigella sativa seeds and Thymus vulgaris mixture to antibiotics-free rations of vaccinated and non-vaccinated male broilers on growth performance, antibody titer and haematological profile

    Directory of Open Access Journals (Sweden)

    Mamoun Z. Athamneh

    2010-04-01

    Full Text Available This research explores an experimental study conducted to investigate the effect of crushed Pimpinella anisum (PA, Nigella sativa (NS seeds and Thymus vulgaris (TV mixture as a feed additive on growth performance and mortality rate (MR, selected antibodies titer (Ab’s and blood hematological profile of vaccinated and non-vaccinated Lohman male broiler chicks fed free-antibiotics ration. A total of 400 one-day old chicks were distributed into 16 groups (4 treatment x 4 replicates x 25chicks. The experiment lasted from one to 42 days of age. The statistical findings of this experiment prove that the use of medicinal plants mixture improves live body weight, body weight gain, feed conversion ratio and MR of vaccinated male broilers at 21 and 42 days of age. antibodies titer against infectious bronchitis and infectious bursal disease of non-vaccinated and vaccinated male broilers were significantly improved at 21 and 42 days as a result of the addition of medicinal plant mixture to the basal ration. Concerning Newcastle disease, the use of PA, NS and TV mixture did not reflect in any additional improvement of Ab's than vaccines did. The addition of medicinal plants mixture increases WBC's, RBC's, thrombocytes count and Hb concentration of vaccinated and non-vaccinated male broilers at 21 days of age. Meanwhile, heterophils, lymphocytes and monocytes of vaccinated male broilers (VMB were significantly improved by adding medicinal plant mixture to their basal diet. Moreover, at 42 days of age the use of PA, NS seeds and TV mixture indicate significant increase in total WBC’s, lymphocytes and monocytes and monocytes count of VMB and non-vaccinated male broiler (NVMB. No significant differences were noticed in RBC’s and Hct as a result of feeding crushed medicinal plants mixture.

  5. [Determination of hemagglutination inhibiting antibodies against influenza virus A/Port Chalmers/1/73 in samples from the Roman population (1962-1974). Relation of antibody titers to those obtained against previous influenza A strains].

    Science.gov (United States)

    Castagnari, L; Delia, S; Russo, V; Sebastiani, A

    1975-01-01

    The h.i.a. titer has been determined against the strain of the A/Port Chalmers/1/73 influenza virus in 805 serum samples obtained in Rome from as many adults during six distinct periods between spring 1962 and summer-autumn 1974.

  6. Antibody titers against vaccine and contemporary wild poliovirus type 1 in children immunized with IPV+OPV and young adults immunized with OPV.

    Science.gov (United States)

    Lukashev, Alexander N; Yarmolskaya, Maria S; Shumilina, Elena Yu; Sychev, Daniil A; Kozlovskaya, Liubov I

    2016-02-02

    In 2010, a type 1 poliovirus outbreak in Congo with 445 lethal cases was caused by a virus that was neutralized by sera of German adults vaccinated with inactivated polio vaccine with a reduced efficiency. This seroprevalence study was done in two cohorts immunized with other vaccination schedules. Russian children aged 3-6 years immunized with a combination of inactivated and live polio vaccines were reasonably well protected against any wild type poliovirus 1, including the Congolese isolate. Adults aged 20-29 years immunized only with live vaccine were apparently protected against the vaccine strain (92% seropositive), but only 50% had detectable antibodies against the Congo-2010 isolate. Both waning immunity and serological divergence of the Congolese virus could contribute to this result. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Improved survival in rhesus macaques immunized with modified vaccinia virus Ankara recombinants expressing simian immunodeficiency virus envelope correlates with reduction in memory CD4+ T-cell loss and higher titers of neutralizing antibody.

    Science.gov (United States)

    Ourmanov, Ilnour; Kuwata, Takeo; Goeken, Robert; Goldstein, Simoy; Iyengar, Ranjani; Buckler-White, Alicia; Lafont, Bernard; Hirsch, Vanessa M

    2009-06-01

    Previous studies demonstrated that immunization of macaques with simian immunodeficiency virus (SIV) Gag-Pol and Env recombinants of the attenuated poxvirus modified vaccinia virus Ankara (MVA) provided protection from high viremia and AIDS following challenge with a pathogenic strain of SIV. Although all animals became infected, plasma viremia was significantly reduced in animals that received the MVA-SIV recombinant vaccines compared with animals that received nonrecombinant MVA. Most importantly, the reduction in viremia resulted in a significant increase in median and cumulative survival. Continued analysis of these animals over the subsequent 9 years has shown that they maintain a survival advantage, although all but two of the macaques have progressed to AIDS. Importantly, improved survival correlated with preservation of memory CD4(+) T cells in the peripheral blood. The greatest survival advantage was observed in macaques immunized with regimens containing SIV Env, and the titer of neutralizing antibodies to the challenge virus prior to or shortly following challenge correlated with preservation of CD4(+) T cells. These data are consistent with a role for neutralizing antibodies in nonsterilizing protection from high viremia and associated memory CD4(+) T-cell loss.

  8. Efficacy of a parainfluenza virus 5 (PIV5-based H7N9 vaccine in mice and guinea pigs: antibody titer towards HA was not a good indicator for protection.

    Directory of Open Access Journals (Sweden)

    Zhuo Li

    Full Text Available H7N9 has caused fatal infections in humans. A safe and effective vaccine is the best way to prevent large-scale outbreaks in the human population. Parainfluenza virus 5 (PIV5, an avirulent paramyxovirus, is a promising vaccine vector. In this work, we generated a recombinant PIV5 expressing the HA gene of H7N9 (PIV5-H7 and tested its efficacy against infection with influenza virus A/Anhui/1/2013 (H7N9 in mice and guinea pigs. PIV5-H7 protected the mice against lethal H7N9 challenge. Interestingly, the protection did not require antibody since PIV5-H7 protected JhD mice that do not produce antibody against lethal H7N9 challenge. Furthermore, transfer of anti-H7 serum did not protect mice against H7N9 challenge. PIV5-H7 generated high HAI titers in guinea pigs, however it did not protect against H7N9 infection or transmission. Intriguingly, immunization of guinea pigs with PIV5-H7 and PIV5 expressing NP of influenza A virus H5N1 (PIV5-NP conferred protection against H7N9 infection and transmission. Thus, we have obtained a H7N9 vaccine that protected both mice and guinea pigs against lethal H7N9 challenge and infection respectively.

  9. Novel Epstein-Barr virus-like particles incorporating gH/gL-EBNA1 or gB-LMP2 induce high neutralizing antibody titers and EBV-specific T-cell responses in immunized mice.

    Science.gov (United States)

    Perez, Elizabeth M; Foley, Joslyn; Tison, Timelia; Silva, Rute; Ogembo, Javier Gordon

    2017-03-21

    Previous Epstein-Barr virus (EBV) prophylactic vaccines based on the major surface glycoprotein gp350/220 as an immunogen have failed to block viral infection in humans, suggesting a need to target other viral envelope glycoproteins. In this study, we reasoned that incorporating gH/gL or gB, critical glycoproteins for viral fusion and entry, on the surface of a virus-like particle (VLP) would be more immunogenic than gp350/220 for generating effective neutralizing antibodies to prevent viral infection of both epithelial and B cell lines. To boost the humoral response and trigger cell-mediated immunity, EBV nuclear antigen 1 (EBNA1) and latent membrane protein 2 (LMP2), intracellular latency proteins expressed in all EBV-infected cells, were also included as critical components of the polyvalent EBV VLP. gH/gL-EBNA1 and gB-LMP2 VLPs were efficiently produced in Chinese hamster ovary cells, an FDA-approved vehicle for mass-production of biologics. Immunization with gH/gL-EBNA1 and gB-LMP2 VLPs without adjuvant generated both high neutralizing antibody titers in vitro and EBV-specific T-cell responses in BALB/c mice. These data demonstrate that will be invaluable not only in preventing EBV infection, but importantly, in preventing and treating the 200,000 cases of EBV-associated cancers that occur globally every year.

  10. Production and characterization of monoclonal antibodies to E1 Tor toxin co-regulated pilus of Vibrio cholerae.

    Science.gov (United States)

    Falero, G; Rodríguez, B L; Rodríguez, I; Campos, J; Ledon, T; Valle, E; Silva, Y; Marrero, K; Suzarte, E; Valmaseda, T; Moreno, A; Fando, R

    2003-10-01

    Murine monoclonal antibodies (MAbs) against Vibrio cholerae toxin co-regulated pilus (TCP) were generated using conventional hybridoma procedures. Four hybridomas were obtained and two characterized. Hybridomas 10E10E1 and 4D6F9 secreted antibodies of the IgG2a and IgG1 isotypes, respectively, that reacted with a 24-kDa antigen corresponding to the product of the El Tor tcpA gene fused to a six Histidine tail. Additionally, MAbs produced by 4D6F9 selectively recognized the major pilin subunit (TcpA) of El Tor and O139 vibrios in western immunoblot, while MAbs from 10E10E1 also cross-reacted with classical TcpA. Furthermore, vibrios expressing TCP on their surface selectively inhibited binding of the antibodies secreted by both hybridomas to TcpA-coated microtiter plates. Thus, the MAbs reported in this work detected the structural subunit of the pilus either denatured or assembled on the bacterial surface.

  11. Antibodies against a peptide of cholera toxin differing in cross-reactivity with the toxin differ in their specific interactions with the peptide as observed by sup 1 H NMR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Anglister, J.; Zilber, B. (Weizmann Institute of Science, Rehovot (Israel))

    1990-01-30

    The interactions between the aromatic residues of the monoclonal antibody TE34, and its peptide antigen CTP3, have been studied by 2D TRNOE difference spectroscopy. The sequence of CTP3 corresponds to residues 50-64 of the B subunit of cholera toxin (VEVPGSQHIDSQKKA). Unlike two previously studied anti-CTP3 antibodies (TE32 and TE33), the TE34 antibody does not bind the toxin. The off-rate of CTP3 from TE34 was found to be too slow to measure strong TRNOE cross-peaks between the antibody and the peptide. Much faster off-rates, resulting in a strong TRNOE, were obtained for two peptide analogues: (a) CTP3 with an amide in the C-terminus (VEVPGSQHIDSQKKA-NH{sub 2}) and (b) a truncated version of the peptide (N-acetyl-IDSQKKA). These modifications do not interfere significantly either with the interactions of the unmodified part of the peptide with the antibody or with intramolecular interactions occurring in the epitope recognized by the antibody. The combined use of these peptides allows us to study the interactions between the antibody and the whole peptide. Two tyrosine residues and one or more tryptophan and phenylalanine residues have been found to interact with histidine-8, isoleucine-9, aspartate-10, lysine-13 and/or lysine-14, and alanine-15 of the peptide. The strong interaction of TE34 with the negatively charged C-terminus of CTP3 is one of the main reasons for its lack of cross-reactivity with the native toxin. Similar use of modified peptides may extend the applicability of 2D TRNOE difference spectroscopy to the study of other antibody-peptide complexes involving slow peptide off-rates.

  12. A Fast and Inexpensive Protocol for Empirical Verification of Neutralizing Epitopes in Microbial Toxins and Enzymes

    Directory of Open Access Journals (Sweden)

    Christine N. Vuong

    2017-06-01

    Full Text Available In vivo targeting of peptides to antigen-presenting cells by use of agonistic anti-CD40 monoclonal antibodies has been used successfully as an immune response enhancing strategy. When tested in chickens, the antibody-guided platform was capable of inducing specific IgG production within 1 week postimmunization. However, use of this method beyond its initial conception as a vaccine delivery tool has not been fully exploited. In this study, Clostridium perfringens alpha-toxin was used as a model microbial toxin for epitope mapping by using the antibody-guided immunization method to generate a panel of antibodies against specific, regions of the toxin in an attempt to identify crucial determinants on the toxin which, once bound, would hinder downstream toxicity. Alpha-toxin, which possesses both hemolytic and phospholipase C (PLC enzymatic activities, has long been known to be one of the key destructive etiological agents of necrotic enteritis disease in poultry. Previous attempts to identify crucial antigenic determinants on the toxin mediating its enzymatic activities have been performed using expensive and labor-intensive site-directed mutagenesis techniques. To create a panel of antibodies, 23 short candidate alpha-toxin peptide regions were selected in silico using B-cell epitope prediction algorithms in the public domain and were custom synthesized to load onto the antibody-guided complex for immunization in birds for antisera production. Peptide-specific antibody responses were generated against all candidate neutralizing epitopes and used for in vitro toxin neutralization tests. Antisera against all 23 peptides were able to neutralize the toxin’s hemolytic activity, with neutralization titers ranging from 80 to 320, but none were effective in blocking PLC. The novel approach of antibody-guided immunization introduces a new, inexpensive method for polyclonal IgG production and de facto identification of neutralizing epitopes in microbial

  13. Protein A chromatography at high titers.

    Science.gov (United States)

    Natarajan, Venkatesh; Zydney, Andrew L

    2013-09-01

    The large increase in antibody titers over the past two decades has created significant challenges for downstream processes; however, there have been no quantitative studies of the effect of feed concentration on the dynamic binding capacity in Protein A chromatography. Small scale experiments were performed using pre-packed ProSep® Ultra Plus columns over a range of feed flow rates and antibody concentrations. The data clearly demonstrate that the dynamic binding capacity decreases with increasing concentration of the monoclonal antibody at short residence times. This reduction in DBC is due to non-equilibrium mass transfer effects in the porous resin, with the experimental results consistent with predictions of a simple mathematical model based on a linear driving force with solid phase diffusion. These results provide important insights into the behavior of Protein A chromatography and provide a framework for the proper design of Protein A capture steps for high titer products. Copyright © 2013 Wiley Periodicals, Inc.

  14. Engineering Venom’s Toxin-Neutralizing Antibody Fragments and Its Therapeutic Potential

    Directory of Open Access Journals (Sweden)

    Larissa M. Alvarenga

    2014-08-01

    Full Text Available Serum therapy remains the only specific treatment against envenoming, but anti-venoms are still prepared by fragmentation of polyclonal antibodies isolated from hyper-immunized horse serum. Most of these anti-venoms are considered to be efficient, but their production is tedious, and their use may be associated with adverse effects. Recombinant antibodies and smaller functional units are now emerging as credible alternatives and constitute a source of still unexploited biomolecules capable of neutralizing venoms. This review will be a walk through the technologies that have recently been applied leading to novel antibody formats with better properties in terms of homogeneity, specific activity and possible safety.

  15. Design of Fab-based chimeric antibodies against Bothrops asper toxins

    DEFF Research Database (Denmark)

    M. Haack, Aleksander; B. Hallgren, Malte; U. W. Friis, Rasmus

    Snakebite is one of the world’s most neglected tropical diseases, with an estimated 5 million bites per year, resulting in about 125.000 deaths. The only current treatment for snakebite envenoming is antiserum derived from the blood of immunized mammals(typically horses). These antisera are expen...... are expensive to produce and carry a high risk of causing hyper-allergic reactions in human recipients due to their heterologous origin. Here we report the discovery of chimeric scFvs against Bothrops asper toxins....

  16. Anti-idiotypic antibody-induced protection against Clostridium perfringens type D.

    OpenAIRE

    Percival, D A; Shuttleworth, A D; Williamson, E D; Kelly, D C

    1990-01-01

    A monoclonal antibody (BALB/c mouse) with specificity for a neutralizing epitope on the epsilon-toxin produced by Clostridium perfringens type D was used to raise anti-idiotypic antibodies (anti-Id) in different strains of mice and rabbits. These were purified and used in cross-immunization studies to induce anti-(anti-idiotype). All strains of mice and rabbits immunized with BALB/c-derived anti-Id showed a high-titer antibody response directed towards the active site of the toxin. This prote...

  17. Sensitivity and specificity of indirect ELISA for the detection of antibody titers against BVDV from beef cattle raised in Pará State

    Directory of Open Access Journals (Sweden)

    Rinaldo Batista Viana

    2017-10-01

    Full Text Available The aims of this study were to establish the prevalence of anti-bovine viral diarrhea virus (BVDV antibodies (Ab in beef cattle raised in Pará state, to compare the prevalence of seropositive animals to BVDV using a commercial indirect enzyme-linked immunosorbent assay kit (iELISA and the virus neutralization (VN test, and finally, to determine the sensitivity (Se and specificity (Sp of the iELISA for the detection of anti-BVDV Ab using VN as a gold standard. A total of 400 serum blood samples from Nelore cows aged at least 24 months from five farms in the Pará state from two mesoregions (Metropolitan Region of Belem and Northeast of Pará were analyzed. All animals were vaccinated against brucellosis and foot-and-mouth disease. The examination of anti-BVDV Ab with VN was performed in the Laboratory of Bovine Viruses of the Biological Institute of Sao Paulo as described in the Manual of Diagnostic Tests and Vaccines for Terrestrial Animals. For VN, bovine kidney epithelial cells from the Madin Darby Bovine Kidney (MDBK strain were used. The determinations of anti-BVDV Ab were performed with the iELISA test at the Laboratory of Immunology and Microbiology of the Federal Rural University of Amazonia according to the manufacturer's recommendations. The results were classified as follows: (a correct positive diagnosis, (b incorrect positive diagnosis, (c correct negative diagnosis, and (d incorrect negative diagnosis, according to the results obtained from VN. From the values obtained from VN and iELISA, Se [(a ÷ a + d × 100], Sp [(c ÷ c + b × 100], positive predictive value [(a ÷ a + B × 100], and negative predictive value [(c ÷ c + d × 100] were calculated for iELISA. The frequencies (% of seropositive animals were determined and compared both between the different tests (iELISA and VN and between the different farms (1, 2, 3, 4, and 5. The statistical analysis was performed with a significance level of 5%. The prevalence of seropositive

  18. Recombinant Protein Containing B-Cell Epitopes of Different Loxosceles Spider Toxins Generates Neutralizing Antibodies in Immunized Rabbits

    Directory of Open Access Journals (Sweden)

    Sabrina de Almeida Lima

    2018-04-01

    Full Text Available Loxoscelism is the most important form of araneism in South America. The treatment of these accidents uses heterologous antivenoms obtained from immunization of production animals with crude loxoscelic venom. Due to the scarcity of this immunogen, new alternatives for its substitution in antivenom production are of medical interest. In the present work, three linear epitopes for Loxosceles astacin-like protease 1 (LALP-1 (SLGRGCTDFGTILHE, ENNTRTIGPFDYDSIMLYGAY, and KLYKCPPVNPYPGGIRPYVNV and two for hyaluronidase (LiHYAL (NGGIPQLGDLKAHLEKSAVDI and ILDKSATGLRIIDWEAWR from Loxosceles intermedia spider venom were identified by SPOT-synthesis technique. One formerly characterized linear epitope (DFSGPYLPSLPTLDA of sphingomyelinase D (SMase D SMase-I from Loxosceles laeta was also chosen to constitute a new recombinant multiepitopic protein. These epitopes were combined with a previously produced chimeric multiepitopic protein (rCpLi composed by linear and conformational B-cell epitopes from SMase D from L. intermedia venom, generating a new recombinant multiepitopic protein derived from loxoscelic toxins (rMEPLox. We demonstrated that rMEPLox is non-toxic and antibodies elicited in rabbits against this antigen present reactivity in ELISA and immunoblot assays with Brazilian L. intermedia, L. laeta, L. gaucho, and L. similis spider venoms. In vivo and in vitro neutralization assays showed that anti-rMEPLox antibodies can efficiently neutralize the sphingomyelinase, hyaluronidase, and metalloproteinase activity of L. intermedia venom. This study suggests that this multiepitopic protein can be a suitable candidate for experimental vaccination approaches or for antivenom production against Loxosceles spp. venoms.

  19. MF59- and Al(OH)3-Adjuvanted Staphylococcus aureus (4C-Staph) Vaccines Induce Sustained Protective Humoral and Cellular Immune Responses, with a Critical Role for Effector CD4 T Cells at Low Antibody Titers

    Science.gov (United States)

    Monaci, Elisabetta; Mancini, Francesca; Lofano, Giuseppe; Bacconi, Marta; Tavarini, Simona; Sammicheli, Chiara; Arcidiacono, Letizia; Giraldi, Monica; Galletti, Bruno; Rossi Paccani, Silvia; Torre, Antonina; Fontana, Maria Rita; Grandi, Guido; de Gregorio, Ennio; Bensi, Giuliano; Chiarot, Emiliano; Nuti, Sandra; Bagnoli, Fabio; Soldaini, Elisabetta; Bertholet, Sylvie

    2015-01-01

    Staphylococcus aureus (S. aureus) is an important opportunistic pathogen that may cause invasive life-threatening infections, like sepsis and pneumonia. Due to the increasing antibiotic resistance, the development of an effective vaccine against S. aureus is needed. Although a correlate of protection against staphylococcal diseases is not yet established, several findings suggest that both antibodies and CD4 T cells might contribute to optimal immunity. In this study, we show that adjuvanting a multivalent vaccine (4C-Staph) with MF59, an oil-in-water emulsion licensed in human vaccines, further potentiated antigen-specific IgG titers and CD4 T-cell responses compared to alum and conferred protection in the peritonitis model of S. aureus infection. Moreover, we showed that MF59- and alum-adjuvanted 4C-Staph vaccines induced persistent antigen-specific humoral and T-cell responses, and protected mice from infection up to 4 months after immunization. Furthermore, 4C-Staph formulated with MF59 was used to investigate which immune compartment is involved in vaccine-induced protection. Using CD4 T cell-depleted mice or B cell-deficient mice, we demonstrated that both T and B-cell responses contributed to 4C-Staph vaccine-mediated protective immunity. However, the role of CD4 T cells seemed more evident in the presence of low-antibody responses. This study provides preclinical data further supporting the use of the adjuvanted 4C-Staph vaccines against S. aureus diseases, and provides critical insights on the correlates of protective immunity necessary to combat this pathogen. PMID:26441955

  20. MF59- and Al(OH3-adjuvanted Staphylococcus aureus (4C-Staph vaccines induce sustained protective humoral and cellular immune responses, with a critical role for effector CD4 T cells at low antibody titers.

    Directory of Open Access Journals (Sweden)

    Elisabetta eMonaci

    2015-09-01

    Full Text Available Staphylococcus aureus (S. aureus is an important opportunistic pathogen that may cause invasive life-threatening infections like sepsis and pneumonia. Due to increasing antibiotic-resistance, the development of an effective vaccine against S. aureus is needed. Although a correlate of protection against staphylococcal diseases is not yet established, several findings suggest that both antibodies and CD4 T cells might contribute to optimal immunity. In this study, we show that adjuvanting a multivalent vaccine (4C-Staph with MF59, an oil-in-water emulsion licensed in human vaccines, further potentiated antigen-specific IgG titers and CD4 T cell responses compared to alum and conferred protection in the peritonitis model of S. aureus infection. Moreover, we showed that MF59- and alum-adjuvanted 4C-Staph vaccines induced persistent antigen-specific humoral and T cell responses, and protected mice from infection up to 4 months after immunization. Furthermore, 4C-Staph formulated with MF59 was used to investigate which immune compartment is involved in vaccine-induced protection. Using CD4 T cell-depleted mice or B cell deficient mice, we demonstrated that both T and B cell responses contributed to 4C-Staph vaccine-mediated protective immunity. However, the role of CD4 T cells seemed more evident in the presence of low antibody responses. This study provides preclinical data further supporting the use of the adjuvanted 4C-Staph vaccines against S. aureus diseases, and provides critical insights on the correlates of protective immunity necessary to combat this pathogen.

  1. Development of recombinant antivenoms based on mixtures of human antibodies against D. polylepis toxins

    DEFF Research Database (Denmark)

    Knudsen, Cecilie; Andersen, Mikael Rørdam; Lohse, Brian

    With an annual 150,000 deaths and countless amputations and disfigurements, snakebite envenoming is an ever-present threat in many parts of the rural tropical world1. In sub-Saharan Africa, only 1-2% of victims are treated with antivenom, which is currently based on animal-derived antibodies. Due...... to their heterologous origin, antivenoms often provoke serious side effects in human recipients, such as serum sickness and anaphylaxis, which in some cases leads to death.......With an annual 150,000 deaths and countless amputations and disfigurements, snakebite envenoming is an ever-present threat in many parts of the rural tropical world1. In sub-Saharan Africa, only 1-2% of victims are treated with antivenom, which is currently based on animal-derived antibodies. Due...

  2. Antibody Responses in the Nonhuman Primate, Macaca Fascicularis, to Protein Toxins

    Science.gov (United States)

    1990-05-01

    Desensitization t patients to bee venom or dust mite involves chronic exposure to the partiular antigen. Patients in which desensitization is ef ective...to manipulate various parameters of disease and therapy not possible in humans. Historically, the use of animal models dates at least to the...various therapies and normal physiologic changes such as during pregnancy (Rao 1980), neonatal status (Einhorn 1987), age related decline in antibody

  3. Production of Chicken Egg Yolk Antibody (IgY) Against Recombinant Cholera Toxin B Subunit and Evaluation of Its Prophylaxis Potency in Mice.

    Science.gov (United States)

    Barati, Babak; Ebrahimi, Firouz; Nazarian, Shahram

    2018-03-01

    Cholera toxin (CT), responsible for the harmful effects of cholera infection, is made up of one A subunit (enzymatic), and five B subunits (cell binding). The release of cholera toxin is the main reason for the debilitating loss of intestinal fluid. Inhibition of the B subunit (CTB) may block CT activity. To determine the effect of anti CTB-IgY against oral challenge with V. cholera in suckling infant mice. The binding domain of cholera toxin was amplified and ligated into pET28a vector. The pET28a (+)/ctb expression vector was confirmed by endonuclease digestion and sequence analysis. The expression of recombinant CTB in E. coli was performed by induction with IPTG. After immunizing the chickens with recombinant CTB, IgY was purified by water dilution method and NaCl precipitation and analyzed by SDS-PAGE. Moreover, the activity and specificity of the IgY antibody were assessed by ELISA. The SDS-PAGE and western blot techniques showed that CTB protein was successfully expressed and specifically recognized by polyclonal antibodies against the cholera toxin. The oral administration of anti- (V. cholera+CTB) in infant mice in challenge with active V. cholera bacterium demonstrated high rate of survival. The increase in the number of antibiotic resistant bacteria implies the necessity of finding novel antibiotics. Our results suggest the possibility of passive protection from purified IgY, hence implying that anti CTB-IgY may be useful in the treatment of cholera infections.

  4. Monoclonal Antibody Combinations that Present Synergistic Neutralizing Activity: A Platform for Next-Generation Anti-Toxin Drugs.

    Science.gov (United States)

    Diamant, Eran; Torgeman, Amram; Ozeri, Eyal; Zichel, Ran

    2015-05-29

    Monoclonal antibodies (MAbs) are among the fastest-growing therapeutics and are being developed for a broad range of indications, including the neutralization of toxins, bacteria and viruses. Nevertheless, MAbs potency is still relatively low when compared to conventional polyclonal Ab preparations. Moreover, the efficacy of an individual neutralizing MAb may significantly be hampered by the potential absence or modification of its target epitope in a mutant or subtype of the infectious agent. These limitations of individual neutralizing MAbs can be overcome by using oligoclonal combinations of several MAbs with different specificities to the target antigen. Studies conducted in our lab and by others show that such combined MAb preparation may present substantial synergy in its potency over the calculated additive potency of its individual MAb components. Moreover, oligoclonal preparation is expected to be better suited to compensating for reduced efficacy due to epitope variation. In this review, the synergistic neutralization properties of combined oligoclonal Ab preparations are described. The effect of Ab affinity, autologous Fc fraction, and targeting a critical number of epitopes, as well as the unexpected contribution of non-neutralizing clones to the synergistic neutralizing effect are presented and discussed.

  5. Monoclonal Antibody Combinations that Present Synergistic Neutralizing Activity: A Platform for Next-Generation Anti-Toxin Drugs

    Directory of Open Access Journals (Sweden)

    Eran Diamant

    2015-05-01

    Full Text Available Monoclonal antibodies (MAbs are among the fastest-growing therapeutics and are being developed for a broad range of indications, including the neutralization of toxins, bacteria and viruses. Nevertheless, MAbs potency is still relatively low when compared to conventional polyclonal Ab preparations. Moreover, the efficacy of an individual neutralizing MAb may significantly be hampered by the potential absence or modification of its target epitope in a mutant or subtype of the infectious agent. These limitations of individual neutralizing MAbs can be overcome by using oligoclonal combinations of several MAbs with different specificities to the target antigen. Studies conducted in our lab and by others show that such combined MAb preparation may present substantial synergy in its potency over the calculated additive potency of its individual MAb components. Moreover, oligoclonal preparation is expected to be better suited to compensating for reduced efficacy due to epitope variation. In this review, the synergistic neutralization properties of combined oligoclonal Ab preparations are described. The effect of Ab affinity, autologous Fc fraction, and targeting a critical number of epitopes, as well as the unexpected contribution of non-neutralizing clones to the synergistic neutralizing effect are presented and discussed.

  6. [Serum immunoglobulin IgG subclass distribution of antibody responses to pertussis toxin and filamentous hemagglutinin of Bordetella pertussis in patients with whooping cough].

    Science.gov (United States)

    Rastawicki, Waldemar; Smietańska, Karolina; Rokosz-Chudziak, Natalia; Jagielski, Marek

    2013-01-01

    The present study was aimed at determining the IgG subclass distribution against pertussis toxin (PT) and filamentous hemagglutinin (FHA) of Bordetella pertussis in patients with whooping cough. The total number of 222 serum samples obtained from patients suspected in clinical investigation for pertussis were tested separately by in-house ELISA for the presence of IgG antibodies to pertussis toxin and filamentous hemagglutinin. The percentage distribution of specific anti-PT and anti-FHA IgG subclass response was calculated only on the basis of group of sera confirmed in the present study as positive for total IgG antibodies (183 sera to PT antigen and 129 to FHA antigen). Paired serum specimens were obtained from 36 patients. Based on the results of determining the level of antibodies in the sera of 40 blood donors, the cut-off limit of serum antibodies for each subclass was set at arithmetic mean plus two standard deviations. Antibodies of IgG1 to pertussis toxin and filamentous hemagglutinin were diagnosed in 151 (82.5%) and 99 (76.7%), IgG2 in 72 (39.0%) and 50 (38.8%), IgG3 in 17 (9.3%) and 43 (33.3%), IgG4 in 55 (30.1%) and 53 (41.1%) serum samples, respectively. There were no significant differences in percentage of sera with IgG1, IgG2 and IgG3 in relation to age of the patients. However, the frequency of occurrence of IgG4 antibodies was highest in the group of the youngest children to the age of 6 years old (61.8% for PT and 68.0% for FHA), and decrease with age, reaching the minimum in the group of patients above 40 years old (13.2% and 4.2% for PT and FHA, respectively). We also found significantly higher frequency of IgG4 to PT and FHA antigens in men than in women. Statistically significant, essential changes in the pattern of IgG subclass during the course of infection were not found. In conclusion, this study showed that all four subclasses of IgG antibodies to pertussis toxin and filamentous hemagglutinin are produced during whooping cough.

  7. The monoclonal antibody 26 raised against tetanus toxoid also recognizes tetanus toxin and b2-glycoprotein I – its binding properties in vitro and potential applications

    Directory of Open Access Journals (Sweden)

    ALEKSANDRA B. INIĆ-KANADA

    2009-03-01

    Full Text Available A murine monoclonal IgG1 antibody, marked as MAb26, specific for tetanus toxoid has been immunochemically characterized. By performing enzyme-linked immunosorbent assays (ELISAs and western blot analyses, it was demonstrated that MAb26 reacted with tetanus toxoid, tetanus toxin and b2-glycoprotein I (b2GPI. According to the results, MAb26 recognized the sequential epitope on the tetanus heavy chain. The affinity constant, calculated from Scatchard plots of MAb26 binding to tetanus toxoid, was 1.145´108 M-1 and the measurement of the relative affinity of MAb26 by ELISA using thiocyanate elution showed a significantly higher affinity of MAb26 to the toxoid (p = 0.0012 in comparison to the toxin. Additionally, the reactivity of MAb26 toward the toxoid forms increased when the tetanus toxin was detoxified using 8 mM and higher formaldehyde concentrations. The similarity of the tetanus toxoid to several sera proteins, either at the level of its conformation (IL-1a or at the level of peptide sequences (b2GPI, laminin favors its role in autoimmunity by the mechanism of molecular mimicry. As the induction of an autoimmune disease is dependent on the breakdown of tolerance, which could be the result of an overt hyperstimulation, the control of the presence and concentration of self-reactive epitopes in vaccine preparations is a prerequisite. In this study, it was shown that MAb26 can: 1 discriminate between the tetanus toxin and different toxoid forms, which makes it a good candidate for antibody control during vaccine preparation; 2 due to its cross-reactivity with b2GPI, it could provide information on the presence of a potentially dangerous sequential epitope expressed at the protein surface.

  8. Toxic Shock Syndrome Toxin-1-Mediated Toxicity Inhibited by Neutralizing Antibodies Late in the Course of Continual in Vivo and in Vitro Exposure

    Directory of Open Access Journals (Sweden)

    Norbert Stich

    2014-05-01

    Full Text Available Toxic shock syndrome (TSS results from the host’s overwhelming inflammatory response and cytokine storm mainly due to superantigens (SAgs. There is no effective specific therapy. Application of immunoglobulins has been shown to improve the outcome of the disease and to neutralize SAgs both in vivo and in vitro. However, in most experiments that have been performed, antiserum was either pre-incubated with SAg, or both were applied simultaneously. To mirror more closely the clinical situation, we applied a multiple dose (over five days lethal challenge in a rabbit model. Treatment with toxic shock syndrome toxin 1 (TSST-1 neutralizing antibody was fully protective, even when administered late in the course of the challenge. Kinetic studies on the effect of superantigen toxins are scarce. We performed in vitro kinetic studies by neutralizing the toxin with antibodies at well-defined time points. T-cell activation was determined by assessing T-cell proliferation (3H-thymidine incorporation, determination of IL-2 release in the cell supernatant (ELISA, and IL-2 gene activation (real-time PCR (RT-PCR. Here we show that T-cell activation occurs continuously. The application of TSST-1 neutralizing antiserum reduced IL-2 and TNFα release into the cell supernatant, even if added at later time points. Interference with the prolonged stimulation of proinflammatory cytokines is likely to be in vivo relevant, as postexposure treatment protected rabbits against the multiple dose lethal SAg challenge. Our results shed new light on the treatment of TSS by specific antibodies even at late stages of exposure.

  9. Immunological techniques for detection of fungal and dinoflagellate toxins. Annual report, 1 May 1987-30 April 1988

    Energy Technology Data Exchange (ETDEWEB)

    Chu, F.S.

    1988-05-12

    1) A new direct ELISA, which involves the use of a generic type antibody for T-2 toxin and 3-acetyl-neosolaniol-hemisuccinate (3-Ac-NEOS-HS) conjugated to horseradish peroxidase for the analysis of T-2 toxin metabolites, was established. 2) Analysis of 5 metabolites, i.e., T-2 toxin, HT-2, T-2-4ol, 3'-OH-HT-2, NEOS and a mixture of these five toxins, added at toxin concentrations of 50 and 200 ng/mL of urine, revealed that 87% of the added toxins were recovered analytically at both concentrations in the ELISA, and 69% in RIA and the 200 ppb level. 3) A series of monkey urine samples obtained from a metabolic study was subjected to the new ELISA protocol was as well as to RIA. 4) An extensive study to evaluate a fluorometric method, i.e., hit-and-run assay was made. 5) A direct ELISA for deoxynivalenol (DON) was established. 6) Further improvements for the ELISA for saxitoxin were made. 7) New approaches to produce antibody against nivalenol and saxitoxin were made, but the antibody titers were low. 8) Antibody against microcystin (MCS) was obtained from rabbits after immunizing the animals with MCS-BSA conjugate. 9) A chemical method for the preparation of different monoacetoxyscirpenol (MAS) was established. 10) Routine preparation of different immunochemical reagents continued. Phytotoxins Biological warfare agents; Dinoflagellates. (AW)

  10. Ratio of Circulating IFNγ+ “Th17 Cells” in Memory Th Cells Is Inversely Correlated with the Titer of Anti-CCP Antibodies in Early-Onset Rheumatoid Arthritis Patients Based on Flow Cytometry Methods of the Human Immunology Project

    Directory of Open Access Journals (Sweden)

    Shigeru Kotake

    2016-01-01

    Full Text Available Rheumatoid arthritis (RA is a systemic autoimmune disease with chronic joint inflammation characterized by activated T cells. IL-17 and Th17 cells play important roles in the pathogenesis of RA. Recently, plasticity in helper T cells has been demonstrated; Th17 cells can convert to Th1 cells. However, it remains to be elucidated whether this conversion occurs in the early phase of RA. Here, we validated the methods of the Human Immunology Project using only the cell-surface marker through measuring the actual expression of IL-17 and IFNγ. We also evaluated the expression of CD161 in human Th17 cells. We then tried to identify Th17 cells, IL-17+Th17 cells, and IFNγ+Th17 cells in the peripheral blood of early-onset RA patients using the standardized method of the Human Immunology Project. Our findings validated the method and the expression of CD161. The ratio of IFNγ+Th17 cells in memory T cells was inversely correlated to the titers of anti-CCP antibodies in the early-onset RA patients. These findings suggest that Th17 cells play important roles in the early phase of RA and that anti-IL-17 antibodies should be administered to patients with early phase RA, especially those with high titers of CCP antibodies.

  11. Novel Clostridium difficile Anti-Toxin (TcdA and TcdB Humanized Monoclonal Antibodies Demonstrate In Vitro Neutralization across a Broad Spectrum of Clinical Strains and In Vivo Potency in a Hamster Spore Challenge Model.

    Directory of Open Access Journals (Sweden)

    Hongyu Qiu

    Full Text Available Clostridium difficile (C. difficile infection (CDI is the main cause of nosocomial antibiotic-associated colitis and increased incidence of community-associated diarrhea in industrialized countries. At present, the primary treatment of CDI is antibiotic administration, which is effective but often associated with recurrence, especially in the elderly. Pathogenic strains produce enterotoxin, toxin A (TcdA, and cytotoxin, toxin B (TcdB, which are necessary for C. difficile induced diarrhea and gut pathological changes. Administration of anti-toxin antibodies provides an alternative approach to treat CDI, and has shown promising results in preclinical and clinical studies. In the current study, several humanized anti-TcdA and anti-TcdB monoclonal antibodies were generated and their protective potency was characterized in a hamster infection model. The humanized anti-TcdA (CANmAbA4 and anti-TcdB (CANmAbB4 and CANmAbB1 antibodies showed broad spectrum in vitro neutralization of toxins from clinical strains and neutralization in a mouse toxin challenge model. Moreover, co-administration of humanized antibodies (CANmAbA4 and CANmAbB4 cocktail provided a high level of protection in a dose dependent manner (85% versus 57% survival at day 22 for 50 mg/kg and 20 mg/kg doses, respectively in a hamster gastrointestinal infection (GI model. This study describes the protective effects conferred by novel neutralizing anti-toxin monoclonal antibodies against C. difficile toxins and their potential as therapeutic agents in treating CDI.

  12. Two newly developed methods for the radioactive labeling of tetanus toxins with substances emitting beta-rays and the usefulness of the compounds thus obtained in radioimmunoassays to determine tetanus antibodies

    International Nuclear Information System (INIS)

    Meyer-Eppler, T.

    1986-01-01

    Described are two methods to label tetanus toxins using either 14C-formaldehyde or succinimidyl-3H- propionate as radioactive tracers. The question as to whether the labeled compounds thus obtained can be introduced into RIAs for the detection of tetanus antibodies is also discussed. The immunoreactivity of 3H-toxin is not perceptibly changed by the labeling procedure. The compound can be compared to 125I-labeled toxin, although it suffers no adverse effects from long-term due to autoradiolysis. (TRV) [de

  13. A cross-reacting material CRM197 conjugate vaccine induces diphtheria toxin neutralizing antibody response in children and adolescents infected or not with HIV.

    Science.gov (United States)

    Silva, Giselle P; Santos, Rafaela S; Pereira-Manfro, Wânia F; Ferreira, Bianca; Barreto, Daniella M; Frota, Ana Cristina C; Hofer, Cristina B; Milagres, Lucimar G

    2017-07-05

    Anti-diphtheria antibody levels decrease with aging, and frequent booster vaccinations are required to maintain herd immunity. We analyzed the diphtheria toxin neutralizing antibody (DT-Nab) response induced by a conjugate vaccine (meningococcal C polysaccharide-CRM 197 ) in HIV-vertically infected (HI) children and adolescents and healthy controls (HC) with matched age. We report the association of DT-Nab with the bactericidal antibodies to serogroup C meningococcus (MenC). Before vaccination, 21 HI patients (50%) had no protection against diphtheria (≤0.01IU/ml of antibody) and only 8 (19%) showed complete protection (≥0.1IU/ml). About half of the HC (56%) had complete protection before immunization and 6 subjects (12%) had no protection against diphtheria. After one and two vaccine injections, 96% of HC and 64% of HI vaccinees, respectively, showed full protection against diphtheria. These data indicate that CRM 197 was able to induce primary and/or booster response in both groups of individuals. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. A Quantitative Electrochemiluminescence Assay for Clostridium perfringens alpha toxin

    National Research Council Canada - National Science Library

    Merrill, Gerald A; Rivera, Victor R; Neal, Dwayne D; Young, Charles; Poli, Mark A

    2006-01-01

    .... Biotinylated antibodies to C. perfringens alpha toxin bound to streptavidin paramagnetic beads specifically immunoadsorbed soluble sample alpha toxin which subsequently selectively immunoadsorbed ruthenium (Ru...

  15. Supplemental treatment of rheumatoid arthritis with natural milk antibodies against enteromicrobes and their toxins: results of an open-labelled pilot study

    Directory of Open Access Journals (Sweden)

    Matsuno Takeo

    2011-01-01

    Full Text Available Abstract Background Environmental factors, particularly commensal bacteria in the gastrointestinal tract, may be involved in the pathogenesis of rheumatoid arthritis (RA. The aim of this study was to evaluate whether natural milk antibodies against a wide spectrum of pathogenic enteromicobes and their toxins modify the disease activity in RA. Methods Twenty patients with RA, whose disease activity was uncontrolled by authentic medications due to drug resistance, complications and/or risk factors were treated for 3 months with an oral administration of a whey protein concentrate (WPC containing high levels of natural milk antibodies. Eighteen background-matched RA patients, not supplemented with milk antibody adjunct, were used as controls. Results Statistically significant reduction of arthritis symptoms and improvement of intestinal disorders were observed only in the test group: effective in 8 (44%, possibly effective in 2 (12% and not effective in 8 (44% of 18 patients treated (2 patients withdrew based on an ad hoc "evaluation point", the sum of variables that are improved more than 20% among the 8 core variables used for the American College of Rheumatology (ACR response criteria. This disease modifying effect of the WPC disappeared upon cessation of treatment, but was reappeared upon reintroduction of it. Importantly, 7 of 8 non-responders carry DR15 haplotype (DRB1-1501 and 1502, whereas only 1 of 7 responders was DR15 positive (risk ratio: 6.1. Furthermore, the pre-clinical serum anti-LPS and anti-type II collagen antibody levels in the responders were higher or tended to be higher than those in the non-responders, suggesting that there are 2 sub-types of RA based on an interaction between gastrointestinal pathogens and MHC class II haplotypes. Conclusions The natural milk antibody preparation containing high levels antibodies against pathogenic enteromicrobes and their toxins seems to be effective in a certain RA subset, and deserves

  16. The Effect of Total Cumulative Dose, Number of Treatment Cycles, Interval between Injections, and Length of Treatment on the Frequency of Occurrence of Antibodies to Botulinum Toxin Type A in the Treatment of Muscle Spasticity

    Science.gov (United States)

    Bakheit, Abdel Magid O.; Liptrot, Anthea; Newton, Rachel; Pickett, Andrew M.

    2012-01-01

    A large cumulative dose of botulinum toxin type A (BoNT-A), frequent injections, a short interval between treatment cycles, and a long duration of treatment have all been suggested, but not confirmed, to be associated with a high incidence of neutralizing antibodies to the neurotoxin. The aim of this study was to investigate whether these…

  17. Nano-sized Soluplus® polymeric micelles enhance the induction of tetanus toxin neutralising antibody response following transcutaneous immunisation with tetanus toxoid.

    Science.gov (United States)

    Saydam, Manolya; Cheng, Woei Ping; Palmer, Nathan; Tierney, Robert; Francis, Robert; MacLellan-Gibson, Kirsty; Khan, Ambreen; Mawas, Fatme

    2017-04-25

    The use of Soluplus® polymeric micelles as a novel adjuvant for tetanus toxoid (TTxd) in transcutaneous immunisation was evaluated. TTxd was added to Soluplus® polymeric micelles to form TTxd-Soluplus® nano-aggregates with a size of 68nm. Non-adjuvanted TTxd commonly induces very poor antibody response by the transcutaneous route. However, in this study, the use of TTxd-Soluplus® resulted in a significant increase in the antibody response to TTxd, which was similar to that induced in the presence of CPG-oligodeoxynucleotides (CPG-ODNs) adjuvant. The toxin neutralising potency of the immune sera induced by TTxd-Soluplus® was also much stronger than that from TTxd alone, in a passive transfer experiment in mice. Soluplus® also enhanced the immunogenicity of the toxoid when TTxd-Soluplus® was stored at 4°C for 4weeks, but not at higher temperatures. Confocal microscopy imaging showed a much higher uptake of TTxd in the epidermis and dermis layers of the skin when it was associated with Soluplus®, suggesting that the mechanism for Soluplus® adjuvanticity is through enhanced uptake of the TTxd through the skin. Overall, our findings demonstrated that Soluplus® is an effective novel adjuvant for transcutaneous immunisation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. TÍTULO DE ANTIESTREPTOLISINA O Y FRECUENCIA DE ESTREPTOCOCOS BETAHEMOLÍTICOS EN ESTUDIANTES DE 10 A 15 AÑOS DEL MUNICIPIO FRANCISCO LINARES ALCÁNTARA, ESTADO ARAGUA, VENEZUELA I ASTO TITERS AND BETAHEMOLYTIC STREPTOCOCCI FREQUENCY IN 10 TO 15 YEARS OLD STUDENTS FROM MUNICIPALITY FRANCISCO LINARES ALCANTARA, ARAGUA STATE, VENEZUELA

    Directory of Open Access Journals (Sweden)

    Clara Nancy Gutierrez

    2015-07-01

    Full Text Available Beta-hemolytic streptococci of groups A (EBHGA, Streptococcus pyogenes, C (EBHGC and G (EBHGG induces the production of anti-streptolysin O antibodies (ASTO in infected individuals. In Venezuela, the most common tests used to measure these antibodies are bacterial toxins neutralizing and indirect (passive agglutination with latex particles. Individuals colonized by the aforementioned bacteria can remain as asymptomatic carriers. The purpose of this study was to determine ASO titers and frequency of beta-hemolytic streptococci in 203 students 10-15 years old from the municipality Francisco Linares Alcantara. The ASO titers were determined by neutralization and indirect (passive agglutination tests; EBH frequency was determined through the throat swab culture, which was performed on blood agar at 5%. It was found that 88.6% (180/203 and 53.2% (108/203 of the individuals had normal titers by the method of neutralization and agglutination, respectively. The most frequently isolated EBH belonged to G group (42%, followed by B (26%, A (11% and C (5% groups. There was a large discrepancy between the results from culture and serology. The Fisher exact test found no significant difference between the proportions of high titers for groups of healthy patients and asymptomatic carriers. These results indicate that the behavior of the ASTO titers is similar in both groups.

  19. Antibody Production and Th1-biased Response Induced by an Epitope Vaccine Composed of Cholera Toxin B Unit and Helicobacter pylori Lpp20 Epitopes.

    Science.gov (United States)

    Li, Yan; Chen, Zhongbiao; Ye, Jianbin; Ning, Lijun; Luo, Jun; Zhang, Lili; Jiang, Yin; Xi, Yue; Ning, Yunshan

    2016-06-01

    The epitope vaccine is an attractive potential for prophylactic and therapeutic vaccination against Helicobacter pylori (H. pylori) infection. Lpp20 is one of major protective antigens which trigger immune response after H. pylori invades host and has been considered as an excellent vaccine candidate for the control of H. pylori infection. In our previous study, one B-cell epitope and two CD4(+) T-cell epitopes of Lpp20 were identified. In this study, an epitope vaccine composed of mucosal adjuvant cholera toxin B subunit (CTB) and these three identified Lpp20 epitopes were constructed to investigate the efficacy of this epitope vaccine in mice. The epitope vaccine including CTB, one B-cell, and two CD4(+) T-cell epitopes of Lpp20 was constructed and named CTB-Lpp20, which was then expressed in Escherichia coli and used for intraperitoneal immunization in BALB/c mice. The immunogenicity, specificity, and ability to induce antibodies against Lpp20 and cytokine secretion were evaluated. After that, CTB-Lpp20 was intragastrically immunized to investigate the prophylactic and therapeutic efficacy in infected mice. The results indicated that the epitope vaccine CTB-Lpp20 possessed good immunogenicity and immunoreactivity and could elicit specific high level of antibodies against Lpp20 and the cytokine of IFN-γ and IL-17. Additionally, CTB-Lpp20 significantly decreased H. pylori colonization in H. pylori challenging mice, and the protection was correlated with IgG, IgA, and sIgA antibody and Th1-type cytokines. This study will be better for understanding the protective immunity of epitope vaccine, and CTB-Lpp20 may be an alternative strategy for combating H. pylori invasion. © 2015 John Wiley & Sons Ltd.

  20. Antibody Response to Shiga Toxins in Argentinean Children with Enteropathic Hemolytic Uremic Syndrome at Acute and Long-Term Follow-Up Periods

    Science.gov (United States)

    Fernández-Brando, Romina J.; Bentancor, Leticia V.; Mejías, María Pilar; Ramos, María Victoria; Exeni, Andrea; Exeni, Claudia; Laso, María del Carmen; Exeni, Ramón; Isturiz, Martín A.; Palermo, Marina S.

    2011-01-01

    Shiga toxin (Stx)-producing Escherichia coli (STEC) infection is associated with a broad spectrum of clinical manifestations that include diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome (HUS). Systemic Stx toxemia is considered to be central to the genesis of HUS. Distinct methods have been used to evaluate anti-Stx response for immunodiagnostic or epidemiological analysis of HUS cases. The development of enzyme-linked immunosorbent assay (ELISA) and western blot (WB) assay to detect the presence of specific antibodies to Stx has introduced important advantages for serodiagnosis of HUS. However, application of these methods for seroepidemiological studies in Argentina has been limited. The aim of this work was to develop an ELISA to detect antibodies against the B subunit of Stx2, and a WB to evaluate antibodies against both subunits of Stx2 and Stx1, in order to analyze the pertinence and effectiveness of these techniques in the Argentinean population. We studied 72 normal healthy children (NHC) and 105 HUS patients of the urban pediatric population from the surrounding area of Buenos Aires city. Using the WB method we detected 67% of plasma from NHC reactive for Stx2, but only 8% for Stx1. These results are in agreement with the broad circulation of Stx2-expressing STEC in Argentina and the endemic behavior of HUS in this country. Moreover, the simultaneous evaluation by the two methods allowed us to differentiate acute HUS patients from NHC with a great specificity and accuracy, in order to confirm the HUS etiology when pathogenic bacteria were not isolated from stools. PMID:21559455

  1. Neutralization of dermonecrotic and lethal activities and differences among 32-35 kDa toxins of medically important Loxosceles spider venoms in Brazil revealed by monoclonal antibodies.

    Science.gov (United States)

    Guilherme, P; Fernandes, I; Barbaro, K C

    2001-09-01

    Neutralization of dermonecrotic and lethal activities and differences among the principal toxic proteins (32-35 kDa) of medically important Loxosceles spider venoms in Brazil (Loxosceles gaucho, Loxosceles laeta and Loxosceles intermedia) were studied using monoclonal antibodies (MAbs) produced against the dermonecrotic component (35 kDa) of L. gaucho venom. MAb titers were 512,000 to homologous venom, between 2000 and 64,000 for L. intermedia venom and between 1000 and 64,000 for L. laeta venom. By Western blotting, MAbs could recognize mainly the 35 kDa protein of L. gaucho venom and with less intensity the 35 kDa protein of L. intermedia venom. These MAbs also recognized weakly or did not recognize the 32 kDa component of L. laeta venom. Only MoALg1 showed high affinity for L. gaucho venom and neutralized in vivo 90-97% of the dermonecrotic activity, besides delaying the lethality induced by homologous venom. MoALg1 maintained its capacity to neutralize the dermonecrotic activity, even when administered (i.v.) 6h after envenoming (i.d.). All MAbs obtained failed to neutralize the toxic activities of the heterologous venoms.These results suggest that different epitopes are present in the protein responsible for the dermonecrotic activity of Loxosceles venoms, and confirm the participation of other venom components during the local reaction process. This study also confirms the importance of antibodies for neutralization of dermonecrotic activity, even when administered some hours after envenoming, and emphasizes the differences of composition and toxicity of medically important Loxosceles venoms. These findings must be considered in order to improve loxoscelism immunotherapy.

  2. Antibody titers against Newcastle disease virus in three different poultry management systems located in Feira de Santana – Bahia Títulos de anticorpos contra o vírus da doença de Newcastle em três diferentes sistemas de criação avícola na região de Feira de Santana-Bahia

    Directory of Open Access Journals (Sweden)

    Priscila Sousa da Silva

    2007-12-01

    Full Text Available Serum samples were collected from poultry bred in integrated, independent and backyard production system, in Feira de Santana – Bahia, for evaluation of antibodies against Newcastle Disease virus. Samples were obtained from day-old chicks, slaughter poultry and backyard chickens ranging from four months to three years of age. Serum was analyzed by a commercial indirect ELISA. Results demonstrated that one day old chicks presented high antibodies titers with coefficient of variation of 33.03%, because their mothers were vaccinated. Poultry from integrated and independent producers presented higher variation coefficient, 99.07% and 97.01%, respectively, demonstrating no uniformity in titers, due to the lack of a good vaccinal response against Newcastle disease virus. The occurrence of high antibody titers was observed in backyard chickens, and coefficient of variation of 146.41%, demonstrating the lack of vaccinal response. This data suggest that the studied commercial poultry is not well immunised by vaccination. Moreover, the presence of backyard chickens with evidence of high antibodies titers, suggests that they can become a threat to industrial poultry.Amostras de soro foram coletadas de aves criadas em sistema de produção integrado, sistema independente e de galinhas de fundo de quintal, na região de Feira de Santana – Bahia, para avaliação dos títulos de anticorpos contra o vírus da Doença de Newcastle. Foram obtidas amostras de pintos de um dia, frangos de corte em idade de abate e galinhas de fundo de quintal com idades variando de quatro meses até três anos. Os soros foram analisados por meio de ELISA indireto, utilizando-se kit comercial. Os resultados obtidos demonstraram que os pintos de um dia apresentaram alto título de anticorpos maternos, provenientes das matrizes vacinadas, com coeficiente de variação de 33,03%. Os frangos de corte dos integrados e dos produtores independentes apresentaram um coeficiente de varia

  3. Stool C difficile toxin

    Science.gov (United States)

    ... toxin; Colitis - toxin; Pseudomembranous - toxin; Necrotizing colitis - toxin; C difficile - toxin ... be analyzed. There are several ways to detect C difficile toxin in the stool sample. Enzyme immunoassay ( ...

  4. Targeting Alpha Toxin and ClfA with a Multimechanistic Monoclonal-Antibody-Based Approach for Prophylaxis of Serious Staphylococcus aureus Disease

    Directory of Open Access Journals (Sweden)

    C. Tkaczyk

    2016-06-01

    Full Text Available Staphylococcus aureus produces numerous virulence factors, each contributing different mechanisms to bacterial pathogenesis in a spectrum of diseases. Alpha toxin (AT, a cytolytic pore-forming toxin, plays a key role in skin and soft tissue infections and pneumonia, and a human anti-AT monoclonal antibody (MAb, MEDI4893*, has been shown to reduce disease severity in dermonecrosis and pneumonia infection models. However, interstrain diversity and the complex pathogenesis of S. aureus bloodstream infections suggests that MEDI4893* alone may not provide adequate protection against S. aureus sepsis. Clumping factor A (ClfA, a fibrinogen binding protein, is an important virulence factor facilitating S. aureus bloodstream infections. Herein, we report on the identification of a high-affinity anti-ClfA MAb, 11H10, that inhibits ClfA binding to fibrinogen, prevents bacterial agglutination in human plasma, and promotes opsonophagocytic bacterial killing (OPK. 11H10 prophylaxis reduced disease severity in a mouse bacteremia model and was dependent on Fc effector function and OPK. Additionally, prophylaxis with 11H10 in combination with MEDI4893* provided enhanced strain coverage in this model and increased survival compared to that obtained with the individual MAbs. The MAb combination also reduced disease severity in murine dermonecrosis and pneumonia models, with activity similar to that of MEDI4893* alone. These results indicate that an MAb combination targeting multiple virulence factors provides benefit over a single MAb neutralizing one virulence mechanism by providing improved efficacy, broader strain coverage, and protection against multiple infection pathologies.

  5. 9 CFR 113.452 - Erysipelothrix Rhusiopathiae Antibody.

    Science.gov (United States)

    2010-01-01

    ..., DEPARTMENT OF AGRICULTURE VIRUSES, SERUMS, TOXINS, AND ANALOGOUS PRODUCTS; ORGANISMS AND VECTORS STANDARD... Antibody is a specific antibody product containing antibodies directed against one or more somatic antigens...

  6. Development of a Novel Vaccine Containing Binary Toxin for the Prevention of Clostridium difficile Disease with Enhanced Efficacy against NAP1 Strains.

    Directory of Open Access Journals (Sweden)

    Susan Secore

    Full Text Available Clostridium difficile infections (CDI are a leading cause of nosocomial diarrhea in the developed world. The main virulence factors of the bacterium are the large clostridial toxins (LCTs, TcdA and TcdB, which are largely responsible for the symptoms of the disease. Recent outbreaks of CDI have been associated with the emergence of hypervirulent strains, such as NAP1/BI/027, many strains of which also produce a third toxin, binary toxin (CDTa and CDTb. These hypervirulent strains have been associated with increased morbidity and higher mortality. Here we present pre-clinical data describing a novel tetravalent vaccine composed of attenuated forms of TcdA, TcdB and binary toxin components CDTa and CDTb. We demonstrate, using the Syrian golden hamster model of CDI, that the inclusion of binary toxin components CDTa and CDTb significantly improves the efficacy of the vaccine against challenge with NAP1 strains in comparison to vaccines containing only TcdA and TcdB antigens, while providing comparable efficacy against challenge with the prototypic, non-epidemic strain VPI10463. This combination vaccine elicits high neutralizing antibody titers against TcdA, TcdB and binary toxin in both hamsters and rhesus macaques. Finally we present data that binary toxin alone can act as a virulence factor in animal models. Taken together, these data strongly support the inclusion of binary toxin in a vaccine against CDI to provide enhanced protection from epidemic strains of C. difficile.

  7. Effect of mannanoligosaccharides and/or enzymes on antibody titers against infectious bursal and Newcastle disease viruses Efeito do mananoligossacarídeo e/ou enzimas sobre títulos de anticorpos contra os vírus das doenças de Gumboro e de Newcastle

    Directory of Open Access Journals (Sweden)

    M.C. Oliveira

    2009-02-01

    Full Text Available The effect of including mannanoligosaccharides (MOS and/or enzymes in broiler diets on antibody titers against infectious bursal disease virus (IBDV and Newcastle disease virus (NDV was evaluated. A total of 750 broilers were distributed into a completely randomized experimental design in a factorial arrangement 2 x 2 + 1 with two levels of MOS (0 and 0.1% until 21 days and 0.05% from 22 to 42 days of age, two levels of enzymes (0 and 0.05% and a positive control diet containing antibiotic, totaling five treatments with five replicates each. For antibody analyses, blood samples were weekly collected by jugular vein puncture in the same two birds per replicate. The first and last collections were done at 7 and 42 days of age, respectively. The inclusion of MOS resulted in increased antibody titers against IBDV in the fourth (PO efeito da inclusão de mananoligossacarídeo (MOS e/ou enzimas em dietas de frangos sobre os títulos de anticorpos contra os vírus das doenças de Gumboro (VDG e de Newcastle (VDN. Setecentos e cinqüenta aves foram distribuídas em um delineamento experimental inteiramente ao acaso, em arranjo fatorial 2 x 2 + 1, com dois níveis de MOS (0 e 0,1% até 21 dias e 0,05% de 22 até 42 dias de idade, dois níveis de enzimas (0 e 0,05% e uma dieta-controle-positivo contendo antibióticos, totalizando cinco tratamentos com cinco repetições. Para análise dos anticorpos, amostras de sangue foram colhidas semanalmente por punção da veia jugular em duas aves de cada repetição. A primeira e a última colheita foram realizadas aos sete e 42 dias de idade, respectivamente. A inclusão de MOS resultou em aumento dos títulos contra VDG na quarta (P<0,03 e quinta (P<0,02 semanas, e contra VDN na terceira (P<0,01, quarta (P<0,03 e quinta (P<0,03 semanas de idade. O MOS foi efetivo em estimular a resposta imune humoral contra VDG e VDN vacinais.

  8. Immunization of pregnant cows with Shiga toxin-2 induces high levels of specific colostral antibodies and lactoferrin able to neutralize E. coli O157:H7 pathogenicity.

    Science.gov (United States)

    Albanese, Adriana; Sacerdoti, Flavia; Seyahian, E Abril; Amaral, Maria Marta; Fiorentino, Gabriela; Fernandez Brando, Romina; Vilte, Daniel A; Mercado, Elsa C; Palermo, Marina S; Cataldi, Angel; Zotta, Elsa; Ibarra, Cristina

    2018-03-20

    E. coli O157:H7 is a foodborne pathogen responsible for bloody diarrhea, hemorrhagic colitis and hemolytic uremic syndrome (HUS). The objective of the present work was to evaluate the ability of colostral IgG obtained from Stx2-immunized cows to prevent against E. coli O157:H7 infection and Stx2 cytotoxicity. Hyperimmune colostrum (HC) was obtained from cows intramuscularly immunized with inactivated Stx2 or vehicle for controls. Colostral IgG was purified by affinity chromatography. Specific IgG antibodies against Stx2 and bovine lactoferrin (bLF) levels in HC and the corresponding IgG (HC-IgG/bLF) were determined by ELISA. The protective effects of HC-IgG/bLF against Stx2 cytotoxicity and adhesion of E. coli O157:H7 and its Stx2-negative mutant were analyzed in HCT-8 cells. HC-IgG/bLF prevention against E. coli O157:H7 was studied in human colon and rat colon loops. Protection against a lethal dose of E. coli O157:H7 was evaluated in a weaned mice model. HC-IgG/bLF showed high anti-Stx2 titers and high bLF levels that were able to neutralize the cytotoxic effects of Stx2 in vitro and in vivo. Furthermore, HC-IgG/bLF avoided the inhibition of water absorption induced by E. coli O157:H7 in human colon and also the pathogenicity of E. coli O157:H7 and E. coli O157:H7Δstx2 in rat colon loops. Finally, HC-IgG/bLF prevented in a 100% the lethality caused by E. coli O157:H7 in a weaned mice model. Our study suggests that HC-IgG/bLF have protective effects against E. coli O157:H7 infection. These beneficial effects may be due to specific anti-Stx2 neutralizing antibodies in combination with high bLF levels. These results allow us to consider HC-IgG/bLF as a nutraceutical tool which could be used in combination with balanced supportive diets to prevent HUS. However further studies are required before recommendations can be made for therapeutic and clinical applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

  9. Stabilization of a recombinant ricin toxin A subunit vaccine through lyophilization.

    Science.gov (United States)

    Hassett, Kimberly J; Cousins, Megan C; Rabia, Lilia A; Chadwick, Chrystal M; O'Hara, Joanne M; Nandi, Pradyot; Brey, Robert N; Mantis, Nicholas J; Carpenter, John F; Randolph, Theodore W

    2013-10-01

    Lyophilization was used to prepare dry, glassy solid vaccine formulations of recombinant ricin toxin A-chain containing suspensions of colloidal aluminum hydroxide adjuvant. Four lyophilized formulations were prepared by using combinations of rapid or slow cooling during lyophilization and one of two buffers, histidine or ammonium acetate. Trehalose was used as the stabilizing excipient. Aggregation of the colloidal aluminum hydroxide suspension was reduced in formulations processed with a rapid cooling rate. Aluminum hydroxide particle size distributions, glass transition temperatures, water contents, and immunogenicities of lyophilized vaccines were independent of incubation time at 40 °C for up to 15 weeks. Mice immunized with reconstituted ricin toxin subunit A (RTA) vaccines produced RTA-specific antibodies and toxin-neutralizing antibodies (TNAs) regardless of the length of high temperature vaccine storage or the degree of aluminum adjuvant aggregation that occurred during lyophilization. In murine studies, lyophilized formulations of vaccines conferred protection against exposure to lethal doses of ricin, even after the lyophilized formulations had been stored at 40 °C for 4 weeks. A corresponding liquid formulation of vaccine stored at 40 °C elicited RTA-specific antibody titers but failed to confer immunity during a ricin challenge. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Intranasal Immunization with Influenza Virus-Like Particles Containing Membrane-Anchored Cholera Toxin B or Ricin Toxin B Enhances Adaptive Immune Responses and Protection against an Antigenically Distinct Virus.

    Science.gov (United States)

    Ji, Xianliang; Ren, Zhiguang; Xu, Na; Meng, Lingnan; Yu, Zhijun; Feng, Na; Sang, Xiaoyu; Li, Shengnan; Li, Yuanguo; Wang, Tiecheng; Zhao, Yongkun; Wang, Hualei; Zheng, Xuexing; Jin, Hongli; Li, Nan; Yang, Songtao; Cao, Jinshan; Liu, Wensen; Gao, Yuwei; Xia, Xianzhu

    2016-04-21

    Vaccination is the most effective means to prevent influenza virus infection, although current approaches are associated with suboptimal efficacy. Here, we generated virus-like particles (VLPs) composed of the hemagglutinin (HA), neuraminidase (NA) and matrix protein (M1) of A/Changchun/01/2009 (H1N1) with or without either membrane-anchored cholera toxin B (CTB) or ricin toxin B (RTB) as molecular adjuvants. The intranasal immunization of mice with VLPs containing membrane-anchored CTB or RTB elicited stronger humoral and cellular immune responses when compared to mice immunized with VLPs alone. Administration of VLPs containing CTB or RTB significantly enhanced virus-specific systemic and mucosal antibody responses, hemagglutination inhibiting antibody titers, virus neutralizing antibody titers, and the frequency of virus-specific IFN-γ and IL-4 secreting splenocytes. VLPs with and without CTB or RTB conferred complete protection against lethal challenge with a mouse-adapted homologous virus. When challenged with an antigenically distinct H1N1 virus, all mice immunized with VLPs containing CTB or RTB survived whereas mice immunized with VLPs alone showed only partial protection (80% survival). Our results suggest that membrane-anchored CTB and RTB possess strong adjuvant properties when incorporated into an intranasally-delivered influenza VLP vaccine. Chimeric influenza VLPs containing CTB or RTB may represent promising vaccine candidates for improved immunological protection against homologous and antigenically distinct influenza viruses.

  11. Intranasal Immunization with Influenza Virus-Like Particles Containing Membrane-Anchored Cholera Toxin B or Ricin Toxin B Enhances Adaptive Immune Responses and Protection against an Antigenically Distinct Virus

    Directory of Open Access Journals (Sweden)

    Xianliang Ji

    2016-04-01

    Full Text Available Vaccination is the most effective means to prevent influenza virus infection, although current approaches are associated with suboptimal efficacy. Here, we generated virus-like particles (VLPs composed of the hemagglutinin (HA, neuraminidase (NA and matrix protein (M1 of A/Changchun/01/2009 (H1N1 with or without either membrane-anchored cholera toxin B (CTB or ricin toxin B (RTB as molecular adjuvants. The intranasal immunization of mice with VLPs containing membrane-anchored CTB or RTB elicited stronger humoral and cellular immune responses when compared to mice immunized with VLPs alone. Administration of VLPs containing CTB or RTB significantly enhanced virus-specific systemic and mucosal antibody responses, hemagglutination inhibiting antibody titers, virus neutralizing antibody titers, and the frequency of virus-specific IFN-γ and IL-4 secreting splenocytes. VLPs with and without CTB or RTB conferred complete protection against lethal challenge with a mouse-adapted homologous virus. When challenged with an antigenically distinct H1N1 virus, all mice immunized with VLPs containing CTB or RTB survived whereas mice immunized with VLPs alone showed only partial protection (80% survival. Our results suggest that membrane-anchored CTB and RTB possess strong adjuvant properties when incorporated into an intranasally-delivered influenza VLP vaccine. Chimeric influenza VLPs containing CTB or RTB may represent promising vaccine candidates for improved immunological protection against homologous and antigenically distinct influenza viruses.

  12. Antibodies Directed against Shiga-Toxin Producing Escherichia coli Serotype O103 Type III Secreted Proteins Block Adherence of Heterologous STEC Serotypes to HEp-2 Cells.

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    Taseen S Desin

    Full Text Available Shiga toxin-producing Escherichia coli (STEC serotype O103 is a zoonotic pathogen that is capable of causing hemorrhagic colitis and hemolytic uremic syndrome (HUS in humans. The main animal reservoir for STEC is ruminants and hence reducing the levels of this pathogen in cattle could ultimately lower the risk of STEC infection in humans. During the process of infection, STECO103 uses a Type III Secretion System (T3SS to secrete effector proteins (T3SPs that result in the formation of attaching and effacing (A/E lesions. Vaccination of cattle with STEC serotype O157 T3SPs has previously been shown to be effective in reducing shedding of STECO157 in a serotype-specific manner. In this study, we tested the ability of rabbit polyclonal sera against individual STECO103 T3SPs to block adherence of the organism to HEp-2 cells. Our results demonstrate that pooled sera against EspA, EspB, EspF, NleA and Tir significantly lowered the adherence of STECO103 relative to pre-immune sera. Likewise, pooled anti-STECO103 sera were also able to block adherence by STECO157. Vaccination of mice with STECO103 recombinant proteins induced strong IgG antibody responses against EspA, EspB, NleA and Tir but not against EspF. However, the vaccine did not affect fecal shedding of STECO103 compared to the PBS vaccinated group over the duration of the experiment. Cross reactivity studies using sera against STECO103 recombinant proteins revealed a high degree of cross reactivity with STECO26 and STECO111 proteins implying that sera against STECO103 proteins could potentially provide neutralization of attachment to epithelial cells by heterologous STEC serotypes.

  13. Antibodies Directed against Shiga-Toxin Producing Escherichia coli Serotype O103 Type III Secreted Proteins Block Adherence of Heterologous STEC Serotypes to HEp-2 Cells.

    Science.gov (United States)

    Desin, Taseen S; Townsend, Hugh G; Potter, Andrew A

    2015-01-01

    Shiga toxin-producing Escherichia coli (STEC) serotype O103 is a zoonotic pathogen that is capable of causing hemorrhagic colitis and hemolytic uremic syndrome (HUS) in humans. The main animal reservoir for STEC is ruminants and hence reducing the levels of this pathogen in cattle could ultimately lower the risk of STEC infection in humans. During the process of infection, STECO103 uses a Type III Secretion System (T3SS) to secrete effector proteins (T3SPs) that result in the formation of attaching and effacing (A/E) lesions. Vaccination of cattle with STEC serotype O157 T3SPs has previously been shown to be effective in reducing shedding of STECO157 in a serotype-specific manner. In this study, we tested the ability of rabbit polyclonal sera against individual STECO103 T3SPs to block adherence of the organism to HEp-2 cells. Our results demonstrate that pooled sera against EspA, EspB, EspF, NleA and Tir significantly lowered the adherence of STECO103 relative to pre-immune sera. Likewise, pooled anti-STECO103 sera were also able to block adherence by STECO157. Vaccination of mice with STECO103 recombinant proteins induced strong IgG antibody responses against EspA, EspB, NleA and Tir but not against EspF. However, the vaccine did not affect fecal shedding of STECO103 compared to the PBS vaccinated group over the duration of the experiment. Cross reactivity studies using sera against STECO103 recombinant proteins revealed a high degree of cross reactivity with STECO26 and STECO111 proteins implying that sera against STECO103 proteins could potentially provide neutralization of attachment to epithelial cells by heterologous STEC serotypes.

  14. New monoclonal antibodies against a novel subtype of Shiga toxin 1 produced by Enterobacter cloacae and their use in analysis of human serum

    Science.gov (United States)

    Shiga toxin (Stx) is a major virulence factor for several bacterial pathogens that cause potentially fatal illness, including Escherichia coli and Shigella spp. The continual emergence of new subtypes of Stxs presents challenges in clinical diagnosis of infections caused by Shiga toxin-producing org...

  15. The association of titers to Haemophilus somnus, and other putative pathogens, with the occurrence of bovine respiratory disease and weight gain in feedlot calves.

    Science.gov (United States)

    Martin, S W; Harland, R J; Bateman, K G; Nagy, E

    1998-10-01

    Serum samples were obtained from 602 calves (from 19 groups in four feedlots: three in Ontario, and one in Alberta) upon arrival at the feedlot and 28 d later. Of these calves, 202 developed bovine respiratory disease (BRD) and 400 did not develop BRD. Based on high antibody titers noted upon arrival, we infer that most calves were exposed to Haemophilus somnus prior to arrival at the feedlot. Within a group, calves with high titers on arrival had a reduced risk of developing BRD later. Most calves did not experience titer increases after arrival; however, calves that had stable or increasing titers had a relatively low risk of contracting BRD. The calves at greatest risk of BRD were those with titers on arrival of less than 6.8 units and subsequent titer decreases of more than 1 unit. The effects of both the titer on arrival and the titer change after arrival were stable when the serologic effects of a number of viruses and Mycoplasma agents were considered. Neither antibody titer on arrival nor titer change was related to weight gain differences among calves. Calves with BRD or calves with lower weight on arrival had decreased weight gains in the first 28-day feeding period. The high titers on arrival may have protected most calves against further infection with H. somnus. However, since the calves that developed BRD had large titer increases to a number of viruses and to Pasteurella haemolytica, while having decreased antibody titers to H. somnus, we infer that the existing antibodies were "used up" in combatting the agents, including H. somnus, which may have "caused" the BRD. Calves which were able to increase their antibody levels to H. somnus tended to have a reduced risk of BRD.

  16. Antiradiation Antitoxin IgG : Immunological neutralization of Radiation Toxins at Acute Radiation Syndromes.

    Science.gov (United States)

    Popov, Dmitri; Maliev, Slava

    radiation toxins to induce hyperimmune serum: Group A -Toxoid form of CV ARS toxins ( SRD-1); Group B-Toxoid form of CR ARS (SRD-2)toxins ; Group C -Toxoid form of GI ARS (SRD-3); Group D -Toxoid form of HP ARS (SRD-4). After the hyperimmune serum was pooled from several animals, purified, and concentrated, the IgG fraction was separated. Enzyme-linked immunosorbent assays of the hyper-immune serum had revealed high titers of IgG with specific binding to radi-ation toxins. The antiradiation IgG preparation was injected into laboratory animals one hour before and three hours after irradiation, and was evaluated for its ability to protect inoculated animals against the development of acute radiation syndromes. Results: Animals that were inoculated with specific antiradiation antibodies before and after receiving lethal irradiation at LD 100/30 exhibited 60-75% survival rate within 30 days. Also, these animals inoculated with the Antiradiation Antitoxin had exhibited markedly reduced clinical symptoms of the ARS, even those ones that did not survive irradiation. Discussion: The results of our experiments have demonstrated that the rabbit hyperimmune IgG preparations directed against SRD toxins provide a significant protection against high doses of radiation. In comparison, the mortality rate of irradiated control animals was 100% in the same time period. The mortality rates of animals treated by the hyperimmune IgG antidote have varied in the different groups of ani-mals and different forms of the ARS. However, significant radioprotection was observed in each group treated with the IgGs. The specific antiradiation antidote IGg isolated from hyperim-mune serum of immunized horses is under study. The specific antiradiation antidote contains antibodies to neurotoxins -SAAN IgG includes 50% IgG to Cv ARS, 25% IgG to Cr ARS and 25 % IgG to Gi ARS. The other type of the Specific antiradiation antidote containes antibodies to hematotoxins -SAAH IgG -100%. A combined variant is under

  17. Antibody biotechnology

    African Journals Online (AJOL)

    STORAGESEVER

    2009-07-06

    Jul 6, 2009 ... and automated, the hybrid cells can be stored for many years in liquid nitrogen and antibodies production is homogeneous. The hybridoma method .... they may be modified to vehicle active molecules such as radio-isotopes, toxins, cytokines, enzyme etc. In these cases, the therapeutic effect is due to ...

  18. Maternal titers after adequate syphilotherapy during pregnancy.

    Science.gov (United States)

    Rac, Martha W F; Bryant, Stefanie N; Cantey, Joseph B; McIntire, Donald D; Wendel, George D; Sheffield, Jeanne S

    2015-03-01

    We aimed to construct a timeline for nontreponemal titer decline specific to pregnancy and evaluate factors associated with inadequate decline by delivery. This was a retrospective medical records review from September 1984 to June 2011 of women diagnosed with syphilis after 18 weeks of gestation. Women were treated according to stage of syphilis per Centers for Disease Control and Prevention guidelines. Patients with both pretreatment and delivery titers were included for data analysis. Demographics, stage of syphilis, maternal titers, delivery, and infant outcomes were recorded. Standard statistical analyses were performed for categorical and continuous data. The titer decline was analyzed using mixed-effects regression modeling. A total of 166 patients met inclusion criteria. Mean gestational age at treatment was 29.1 ± 5 weeks, and 93 (56%) women were diagnosed with early-stage syphilis. For all stages of syphilis, maternal titers declined after syphilotherapy. Pretreatment titers were higher and declined more rapidly in primary and secondary disease than in latent-stage disease and syphilis of unknown duration. Sixty-three (38%) patients achieved a 4-fold decline by delivery. Patients without a 4-fold decline by delivery were older (24.6 vs 21.5 years; P syphilis or syphilis of unknown duration, and had less time from treatment to delivery (7.8 vs 11.1 weeks; P < .001). Maternal serologic response during pregnancy after adequate syphilotherapy varied by stage of disease. Failure to achieve a 4-fold decline in titers by delivery is more a reflection of treatment timing than of treatment failure. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  19. Títulos de anticuerpos antisulfátido en pacientes con cardiopatía chagásica crónica y con otras formas de cardiopatía Antisulfatide antibody titers in patients with chronic Chagas heart disease and other forms of heart disease

    Directory of Open Access Journals (Sweden)

    Rando García

    1998-04-01

    ,0049, cardiopatía valvular reumática (P = 0,0075, cardiopatía isquémica crónica (P = 0,0464 y bradiarritmias (P = 0,0157, y valores significativamente bajos en sujetos con cardiopatía hipertensiva (P = 0,0367. Las concentraciones de dichos anticuerpos no se correlacionaron con variables clínicas o paraclínicas indicadoras del grado de afección cardíaca. Los resultados corroboran que los anticuerpos antisulfátido podrían desempeñar algún papel en la patogenia de la cardiomiopatía chagásica y de otras formas de cardiopatía y deben continuarse investigando hasta determinar su posible función en esos procesos.A specific treatment for Chagas' disease has not yet been discovered, even though the condition is endemic in large parts of the Region of the Americas. Earlier studies have addressed the possibility that the sulfatide galactocerebroside in Trypanosoma cruzi behaves as an immunogen involved in the production of the high antisulfatide antibody levels found in patients with chronic infestation with the parasite. This may be an important factor in the pathogenesis of the cardiac symptoms and peripheral neuropathy seen in Chagas' disease, which is the most important cause of myocarditis in Central and South America and the second most important cause of heart failure in several of the countries located in these subregions. The present study was conducted in order to ascertain whether patients with Chagas' disease and other patients not afflicted with the ailment differ insofar as the presence of antibodies against sulfatide is concerned, and it describes antisulfatide antibody levels in 124 hospital patients (74 men and 50 women between the ages of 15 and 94 who were in the cardiology unit of Vargas Hospital in Caracas from 1 July to 30 June 1995. Antisulfatide antibody titers were determined by means of enzyme-linked immunosorbent assays (ELISA, and the antigen employed was sulfatide cerebroside obtained from bovine brain tissue. Of the 124 patients under study

  20. Immunotoxins: The Role of the Toxin

    Directory of Open Access Journals (Sweden)

    David FitzGerald

    2013-08-01

    Full Text Available Immunotoxins are antibody-toxin bifunctional molecules that rely on intracellular toxin action to kill target cells. Target specificity is determined via the binding attributes of the chosen antibody. Mostly, but not exclusively, immunotoxins are purpose-built to kill cancer cells as part of novel treatment approaches. Other applications for immunotoxins include immune regulation and the treatment of viral or parasitic diseases. Here we discuss the utility of protein toxins, of both bacterial and plant origin, joined to antibodies for targeting cancer cells. Finally, while clinical goals are focused on the development of novel cancer treatments, much has been learned about toxin action and intracellular pathways. Thus toxins are considered both medicines for treating human disease and probes of cellular function.

  1. Carbon nanoparticles as detection labels in antibody microarrays. Detection of genes encoding virulence factors in Shiga toxin-producing Escherichia coli.

    NARCIS (Netherlands)

    Noguera, P.S.; Posthuma-Trumpie, G.A.; Tuil, Van M.; Wal, van der F.J.; Boer, De A.; Moers, A.P.H.A.; Amerongen, Van A.

    2011-01-01

    The present study demonstrates that carbon nanoparticles (CNPs) can be used as labels in microarrays. CNPs were used in nucleic acid microarray immunoassays (NAMIAs) for the detection of different Shiga toxin-producing Escherichia coli (STEC) virulence factors: four genes specific for STEC (vt1,

  2. Polyamine toxins

    DEFF Research Database (Denmark)

    Strømgaard, Kristian; Jensen, Lars S; Vogensen, Stine B

    2005-01-01

    Polyamine toxins, isolated from spiders and wasps, have been used as pharmacological tools for the study of ionotropic receptors, but their use have so far been hampered by their lack of selectivity. In this mini-review, we describe how careful synthetic modification of native polyamine toxins ha...

  3. Antineutrophil Cytoplasmic Antibodies, Autoimmune Neutropenia, and Vasculitis

    Science.gov (United States)

    Grayson, Peter C.; Sloan, J. Mark; Niles, John L.; Monach, Paul A.; Merkel, Peter A.

    2011-01-01

    Objectives Reports of an association between antineutrophil cytoplasmic antibodies (ANCA) and autoimmune neutropenia have rarely included cases of proven vasculitis. A case of ANCA-associated vasculitis (AAV) with recurrent neutropenia is described and relevant literature on the association between ANCA, neutropenia, and vasculitis is reviewed. Methods Longitudinal clinical assessments and laboratory findings are described in a patient with AAV and recurrent episodes of profound neutropenia from December 2008 – October 2010. A PubMed database search of the medical literature was performed for papers published from 1960 through October 2010 to identify all reported cases of ANCA and neutropenia. Results A 49 year-old man developed recurrent neutropenia, periodic fevers, arthritis, biopsy-proven cutaneous vasculitis, sensorineural hearing loss, epididymitis, and positive tests for ANCA with specificity for antibodies to both proteinase 3 and myeloperoxidase. Antineutrophil membrane antibodies were detected during an acute neutropenic phase and were not detectable in a post-recovery sample, whereas ANCA titers did not seem to correlate with neutropenia. An association between ANCA and neutropenia has been reported in 74 cases from 24 studies in the context of drug/toxin exposure, underlying autoimmune disease, or chronic neutropenia without underlying autoimmune disease. In these cases, the presence of atypical ANCA patterns and other antibodies were common; however, vasculitis was uncommon and when it occurred was usually limited to the skin and in cases of underlying toxin exposure. Conclusions ANCA is associated with autoimmune neutropenia, but systemic vasculitis rarely occurs in association with ANCA and neutropenia. The interaction between neutrophils and ANCA may provide insight into understanding both autoimmune neutropenia and AAV. PMID:21507463

  4. Low Titer Pneumocystis jirovecii Infections: More than Just Colonization?

    Directory of Open Access Journals (Sweden)

    Alexander Prickartz

    2016-05-01

    Full Text Available Non-pneumonia Pneumocystis jirovecii colonization is thought to occur frequently in immunocompetent individuals. The aim was to analyze if P. jirovecii low-titer detections have more impact than just colonization. From our total cohort of patients for which P. jirovecii testing by qPCR was requested, we selected exclusively those that were fully immunocompetent. Patients were defined as fully immunocompetent if they did not receive immunosuppressive therapy, displayed regular antibody titers, and did not suffer from acquired, inherited or autoimmune diseases. Only those patients with complete medical records available were included. A retrospective analysis identified patients with P. jirovecii colonization and successful antibiotic therapy in response to laboratory pathogen detection. We identified 30 fully immunocompetent patients with P. jirovecii colonization suspected to suffer from infection with the pathogen, but with milder symptoms than pneumonia. All patients were successfully treated with cotrimoxazole against P. jirovecii and resolved from chronic cough and recurrent pulmonary infections. The fact that all patients displayed recovery from their clinical symptoms gives raise to the hypothesis that P. jirovecii infections may also occur in immunocompetent patients but with milder symptoms.

  5. TSH-receptor-autoantibody-titers in untreated toxic diffuse goitres - an early indicator of relapse

    International Nuclear Information System (INIS)

    Becker, W.; Reiners, C.; Boerner, W.

    1984-01-01

    TSH-receptor-auto antibodies were determined in follow-up of 30 patients with relapse of toxic diffuse goitres, i.e. patients with Graves' disease and toxic disseminated autonomy, and in 13 patients with spontaneous remission after antithyroid drug therapy by use of a commercially available TSH-radioreceptorassay (TRAK-assay). All the patients with very high receptor-autoantibody-titers in untreated thyrotoxicosis (F > 20%) had one or more periods of hyperthyroidism or a very severe course of disease. None of these patients showed a spontaneous remission of disease. They all could be identified as Graves' patients. Patients with TRAK-titers 3% [de

  6. First Indian initiative for preparation of low-titer group “O” single-donor platelets with platelet additive solution

    Directory of Open Access Journals (Sweden)

    Puneet Jain

    2018-01-01

    Conclusion: O group SDPs can be prepared with PAS and the beneficial effects were significant with respect to antibody titers. Quality parameters were well maintained. Availability of PAS units has benefitted patients.

  7. Genetic Fusions of Heat-Labile Toxoid (LT) and Heat-Stable Toxin b (STb) of Porcine Enterotoxigenic Escherichia coli Elicit Protective Anti-LT and Anti-STb Antibodies

    Science.gov (United States)

    Zhang, Weiping; Francis, David H.

    2010-01-01

    Enterotoxigenic Escherichia coli (ETEC)-associated diarrhea causes a substantial economic loss to swine producers worldwide. The majority of ETEC strains causing porcine diarrhea, especially postweaning diarrhea (PWD), produce heat-labile toxin (LT) and heat-stable toxin b (STb). LT is commonly used in vaccine development, but STb has not been included because of its poor immunogenicity. As a virulence factor in porcine diarrhea, STb needs to be included as an antigen for development of broad-spectrum vaccines. In this study, we used an LT toxoid (LTR192G [hereafter, LT192]) derived from porcine ETEC to carry a mature STb peptide for LT192-STb fusions to enhance STb immunogenicity for potential vaccine application. Anti-LT and anti-STb antibodies were detected in immunized rabbits and pigs. In addition, when challenged with an STb-positive ETEC strain, all 10 suckling piglets borne by immunized gilts remained healthy, whereas 7 out 9 piglets borne by unimmunized gilts developed moderate diarrhea. This study indicates that the LT192-STb fusion enhanced anti-STb immunogenicity and suggests the LT192-STb fusion antigen can be used in future vaccine development against porcine ETEC diarrhea. PMID:20505006

  8. Notice of CDC's discontinuation of investigational pentavalent (ABCDE) botulinum toxoid vaccine for workers at risk for occupational exposure to botulinum toxins.

    Science.gov (United States)

    2011-10-28

    Effective November 30, 2011, CDC will no longer provide investigational pentavalent (ABCDE) botulinum toxoid (PBT) for vaccination of workers at risk for occupational exposure to botulinum serotypes A, B, C, D, and E. This change might affect persons working in public health laboratories, research facilities, and manufacturing institutions who work with botulinum toxin or neurotoxin-producing species of Clostridium. CDC's decision is based on an assessment of the available data, which indicate a decline in immunogenicity of some of the toxin serotypes. The occurrence of moderate local reactions related to annual booster doses also has increased, which was noted in the 1990s at the U.S. Army Medical Research Institute for Infectious Diseases and resulted in a change in boosting from an annual requirement to only boosting when antibody titers have declined significantly. Additionally, the PBT was manufactured more than 30 years ago. CDC, therefore, has decided not to continue offering this investigational product.

  9. Delta inulin-derived adjuvants that elicit Th1 phenotype following vaccination reduces respiratory syncytial virus lung titers without a reduction in lung immunopathology.

    Science.gov (United States)

    Wong, Terianne M; Petrovsky, Nikolai; Bissel, Stephanie J; Wiley, Clayton A; Ross, Ted M

    2016-08-02

    Respiratory syncytial virus (RSV) is a significant cause of lower respiratory tract infections resulting in bronchiolitis and even mortality in the elderly and young children/infants. Despite the impact of this virus on human health, no licensed vaccine exists. Unlike many other viral infections, RSV infection or vaccination does not induce durable protective antibodies in humans. In order to elicit high titer, neutralizing antibodies against RSV, we investigated the use of the adjuvant Advax™, a novel polysaccharide adjuvant based on delta inulin microparticles, to enhance antibody titers following vaccination. BALB/c mice were vaccinated intramuscularly with live RSV as a vaccine antigen in combination with one of two formulations of Advax™. Advax-1 was comprised of the standard delta inulin adjuvant and Advax-2 was formulated delta inulin plus CpG oligodendronucleotides (ODNs). An additional group of mice were either mock vaccinated, immunized with vaccine only, or administered vaccine plus Imject Alum. Following 3 vaccinations, mice had neutralizing antibody titers that correlated with reduction in viral titers in the lungs. Advax-1 significantly enhanced serum RSV-specific IgG1 levels at week 6 indicative of a Th2 response, similar to titers in mice administered vaccine plus Imject Alum. In contrast, mice vaccinated with vaccine plus Advax-2 had predominately IgG2a titers indicative of a Th1 response that was maintained during the entire study. Interestingly, regardless of which Advax TM adjuvant was used, the neutralizing titers were similar between groups, but the viral lung titers were significantly lower (∼10E+3pfu/g) in mice administered vaccine with either Advax TM adjuvant compared to mice administered adjuvants only. The lung pathology in vaccinated mice with Advax TM was similar to Imject Alum. Overall, RSV vaccine formulated with Advax TM had high neutralizing antibody titers with low lung viral titers, but exacerbated lung pathology compared

  10. A high-throughput, precipitating colorimetric sandwich ELISA microarray for shiga toxins

    Science.gov (United States)

    Shiga toxins 1 and 2 (Stx1 and Stx2) from Shiga toxin-producing E. coli (STEC) bacteria were simultaneously detected with a newly developed, high-throughput antibody microarray platform. The proteinaceous toxins were immobilized and sandwiched between biorecognition elements (monoclonal antibodies)...

  11. Produção e caracterização de anticorpos monoclonais contra toxina épsilon de Clostridium perfringens Tipo D Production and characterization of monoclonal antibodies against Clostridium perfringens Type D epsilon toxin

    Directory of Open Access Journals (Sweden)

    Theonys Diógenes Freitas

    2009-02-01

    Full Text Available Clostridium perfringens tipo D é o agente etiológico da enterotoxemia em ruminantes, causada pela toxina épsilon e caracterizada por edema cardíaco, pulmonar, renal e cerebral. Anticorpos monoclonais contra toxina épsilon de C. perfringens tipo D foram produzidos a partir da fusão da linhagen de mieloma P3-X63-Ag8 653 com células do baço de camundongos Balb/c imunizados com o toxóide épsilon. Seis linhagens de híbridos secretores de anticorpos monoclonais das classes e IgM e IgG foram estabelecidas.Clostridium perfringens type D is the aetiological agent of enterotoxemia in ruminants. The disease is caused by epsilon toxin characterized by cardiac, pulmonary, kidney and brain edema. Monoclonal antibodies were produced by using myeloma cell line P3-X63-Ag8 653 fused with spleen cells from Balb/c mice, immunized with epsilon toxoid of C. perfringens type D. Six hybrids were established secreting monoclonal antibodies of the IgM class and IgG3 subclass.

  12. Botulinum toxin

    Directory of Open Access Journals (Sweden)

    Nigam P

    2010-01-01

    Full Text Available Botulinum toxin, one of the most poisonous biological substances known, is a neurotoxin produced by the bacterium Clostridium botulinum. C. botulinum elaborates eight antigenically distinguishable exotoxins (A, B, C 1 , C 2 , D, E, F and G. All serotypes interfere with neural transmission by blocking the release of acetylcholine, the principal neurotransmitter at the neuromuscular junction, causing muscle paralysis. The weakness induced by injection with botulinum toxin A usually lasts about three months. Botulinum toxins now play a very significant role in the management of a wide variety of medical conditions, especially strabismus and focal dystonias, hemifacial spasm, and various spastic movement disorders, headaches, hypersalivation, hyperhidrosis, and some chronic conditions that respond only partially to medical treatment. The list of possible new indications is rapidly expanding. The cosmetological applications include correction of lines, creases and wrinkling all over the face, chin, neck, and chest to dermatological applications such as hyperhidrosis. Injections with botulinum toxin are generally well tolerated and side effects are few. A precise knowledge and understanding of the functional anatomy of the mimetic muscles is absolutely necessary to correctly use botulinum toxins in clinical practice.

  13. Immunogenicity and efficacy of three recombinant subunit Pasteurella multocida toxin vaccines against progressive atrophic rhinitis in pigs

    Science.gov (United States)

    Liao, Chih-Ming; Huang, Chienjin; Hsuan, Shih-Ling; Chen, Zeng-Weng; Lee, Wei-Cheng; Liu, Cheng-I; Winton, James R.; Chien, Maw-Sheng

    2006-01-01

    Three short fragments of recombinant subunit Pasteurella multocida toxin (rsPMT) were constructed for evaluation as candidate vaccines against progressive atrophic rhinitis (PAR) of swine. PMT-specific antibody secreting cells and evidence of cellular immunity were detected in rsPMT-immunized pigs following authentic PMT challenge or homologous antigen booster. Piglets immunized with rsPMT fragments containing either the N-terminal or the C-terminal portions of PMT developed high titers of neutralizing antibodies. Pregnant sows immunized with rsPMT had higher levels of maternal antibodies in their colostrum than did those immunized with a conventional PAR-toxoid vaccine. Offspring from rsPMT vaccinated sows had better survival after challenge with a five-fold lethal dose of authentic PMT and had better growth performance after challenge with a sublethal dose of toxin. Our findings indicate these non-toxic rsPMT proteins are attractive candidates for development of a subunit vaccine against PAR in pigs.

  14. Effect of centrifugation and microagglutination techniques on Brucella agglutinin titers.

    OpenAIRE

    Klein, G C; Behan, K A; Brown, S L; Couch, E E

    1982-01-01

    The microagglutination technique without centrifugation was more effective than centrifugation of the standard tube test for increasing Brucella agglutinin titers of specimens with a titer greater than or equal to 160 but was less effective than centrifugation of the standard tube test for specimens with a titer less than 160.

  15. Plasmapheresis as preconditioning protocol in an extremely high titer ABO incompatible renal transplant (ABOiRTx) case: A new prospect for chronic kidney disease patients in India.

    Science.gov (United States)

    Pandey, Prashant; Tiwari, Aseem Kumar; Sharma, Jyoti; Dixit, Surbhi; Raina, Vimarsh

    2013-08-01

    The biggest hurdle in renal transplantation is the ABO blood group system. But recently ABO incompatible renal transplants have been performed using plasmapheresis (PP) as a part of the preconditioning protocol. In the present study, the objective of PP along with immunosuppression was to bring down the antibody titer of the patient to ≤ 16 during the transplant and keep it low, around 32, until post-operative 4-14 weeks. The patient (O Negative) had his mother (B Positive) as the ABO non-identical donor. The PP was performed with an apheresis equipment Com.Tec (Fresenius Kabi, Germany) to lower the anti-B antibody titer in the recipient. An Antihuman globulin (AHG) titer was performed for anti-B antibody following the departmental standard operating procedure. A total of 11 plasmapheresis procedures was performed preoperatively and four procedures were performed post-operatively to maintain the titer of the anti-B antibody at or below the desired level. The baseline anti-B antibody titer in the recipient was 512. The baseline titer came down to 8 after the end of the 11th procedure. Post-operatively we performed four plasmapheresis procedures to keep the titer at 32. During the post-operative follow up the titer has been maintained at 32 and the serum creatinine level has been maintained at approximately 1.0mg/dl and other parameters relevant to graft function were within normal limits. Our case could be the first reported case from India in which we used a plasmapheresis procedure as a part of preconditioning protocol instead of using an immunoadsorption column. Furthermore, it could be one of the few ABOiRTx cases, which has been performed at an isoagglutinin titer of 512 using plasma exchange as part of a preconditioning regime. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Definition and dynamic control of a continuous chromatography process independent of cell culture titer and impurities.

    Science.gov (United States)

    Chmielowski, Rebecca A; Mathiasson, Linda; Blom, Hans; Go, Daniel; Ehring, Hanno; Khan, Heera; Li, Hong; Cutler, Collette; Lacki, Karol; Tugcu, Nihal; Roush, David

    2017-12-01

    Advances in cell culture technology have enabled the production of antibody titers upwards of 30g/L. These highly productive cell culture systems can potentially lead to productivity bottlenecks in downstream purification due to lower column loadings, especially in the primary capture chromatography step. Alternative chromatography solutions to help remedy this bottleneck include the utilization of continuous processing systems such as periodic counter-current chromatography (PCC). Recent studies have provided methods to optimize and improve the design of PCC for cell culture titers up to about 3g/L. This paper defines a continuous loading strategy for PCC that is independent of cell culture background and encompasses cell culture titers up to about 31g/L. Initial experimentation showed a challenge with determining a difference in change in UV280nm signal (ie. ΔUV) between cell culture feed and monoclonal antibody (mAb) concentration. Further investigation revealed UV280nm absorbance of the cell culture feedstock without antibody was outside of the linear range of detection for a given cell pathlength. Additional experimentation showed the difference in ΔUV for various cell culture feeds can be either theoretically predicted by Beer's Law given a known absorbance of the media background and impurities or experimentally determined using various UV280nm cell pathlengths. Based on these results, a 0.35mm pathlength at UV280nm was chosen for dynamic control to overcome the background signal. The pore diffusion model showed good agreement with the experimental frontal analysis data, which resulted in definition of a ΔUV setpoint range between 20 and 70% for 3C-PCC experiments. Product quality of the elution pools was acceptable between various cell culture feeds and titers up to about 41g/L. Results indicated the following ΔUV setpoints to achieve robust dynamic control and maintain 3C-PCC yield: ∼20-45% for titers greater than 10g/L depending on UV absorbance of

  17. Antithyroglobulin Antibodies and Antimicrosomal Antibodies in Various Thyroid Diseases

    International Nuclear Information System (INIS)

    Lee, Gwon Jun; Hong, Key Sak; Choi, Kang Won; Lee, Kyu; Koh, Chang Soon; Lee, Mun Ho; Park, Sung Hoe; Chi, Je Geun; Lee, Sang Kook

    1979-01-01

    The authors investigated the incidence of antithyroglobulin antibodies and antibodies and antimicrosomal antibodies measured by tanned red cell hemagglutination method in subjects suffering from various thyroid disorders. 1) In 15 normal patients, neither suffering from any thyroid diseases nor from any other autoimmune disorders, the antithyroglobulin antibodies were all negative, but the antimicrosomal antibody was positive only in one patient (6.7%). 2) The antithyroglobulin antibodies were positive in 31.5% (34 patients) of 108 patients with various thyroid diseases, and the antimicrosomal antibodies were positive in 37.0% (40 patients). 3) of the 25 patients with Graves' diseases, 7 patients (28.0%) showed positive for the antithyroglobulin antibodies, and 9 (36.0%) for the antimicrosomal antibodies. There was no definite differences in clinical and thyroid functions between the groups with positive and negative results. 4) Both antibodies were positive in 16 (88.9%) and 17 (94.4%) patients respectively among 18 patients with Hashimoto's thyroiditis, all of them were diagnosed histologically. 5) Three out of 33 patients with thyroid adenoma showed positive antibodies, and 3 of 16 patients with thyroid carcinoma revealed positive antibodies. 6) TRCH antibodies demonstrated negative results in 2 patients with subacute thyroiditis, but positive in one patient with idiopathic primary myxedema. 7) The number of patients with high titers(>l:802) was 16 for antithyroglobulin antibody, and 62.5% (10 patients) of which was Hashimoto's thyroiditis. Thirteen (65.0) of 20 patients with high titers (>l:802) for antimicrosomal antibody was Hashimoto's thyroiditis. TRCH test is a simple, sensitive method, and has high reliability and reproducibility. The incidences and titers of antithyroglobulin antibody and antimicrosomal antibody are especially high in Hashimoto's thyroiditis.

  18. Titulação de anticorpos contra o vírus da raiva em cães, em Campo Grande, MS, na Campanha Anti-Rábica de 2003 Rabies virus antibody titers in dogs in Campo Grande, Mato Grosso do Sul State, during the anti-rabies campaign, 2003

    Directory of Open Access Journals (Sweden)

    Leonardo Rigo

    2006-12-01

    Full Text Available Para avaliar a resposta imune em cães, que compareceram a Campanha de Vacinação Anti-Rábica Animal de 2003, foram analisados 333 soros caninos, coletados nos diversos postos de vacinação. Verificou-se que 51,1% dos animais não possuíam títulos protetores. Não foi encontrada associação entre aplicação de vacina e maior número de vacinações, com maior título imunitário.To assess the immune response in dogs attended during the 2003 anti-rabies animal vaccination campaign, 333 serum samples collected at different vaccination posts were analyzed. It was found that 51.1% of the animals did not have protective titers. No correlation was found between vaccine application or multiple vaccinations and higher immune titers.

  19. Maternal IgG Anti-A and Anti-B Titer Levels Screening in Predicting ABO Hemolytic Disease of the Newborn: A Meta-Analysis.

    Science.gov (United States)

    Li, Ping; Pang, Li-Hong; Liang, Hai-Feng; Chen, Hong-Yan; Fan, Xiao-Jing

    2015-01-01

    Maternal IgG anti-A/B titers have been considered as a susceptible factor to the risk of ABO hemolytic disease in newborn (ABO-HDN). However, the results remain controversial. This meta-analysis aimed to estimate the association between maternal IgG anti-A/B titers and the risk of ABO-HDN. Trials on the relationship between maternal IgG anti-A/B titers and the risk of ABO-HDN were collected by searching Embase, PubMed, and Cochrane Central Register of Controlled Trials (CENTRAL) electronic databases. The inclusion criteria were maternal IgG anti-A/B titers screening and the evaluation of clinical outcomes in relation to ABO-HDN. Stata 12.0 was used to analyze the data. A total of 23 trials were eligible for inclusion, of which four trials with 5,246 participants were suitable for this meta-analysis. Meta-analysis results suggested that maternal IgG anti-A/B titers were significantly associated with the risk of ABO-HDN [OR = 2.86, 95% CI = 2.50-3.28; OR = 4.67, 95% CI = 3.92-5.55; OR = 1.61, 95% CI = 1.36-1.91 in titers (128 to 256) vs. titers (64 or lower), titers (512 or higher) vs. titers (64 or lower), and titers (512 or higher) vs. titers (128-256), respectively]. Our meta-analysis suggests that maternal IgG anti-A/B titers are significantly associated with the risk of ABO-HDN. They contribute to the prediction of risk of ABO-HDN, in addition to the need for invasive treatment for antibody titers ≥512.

  20. Desensitization protocol in highly HLA-sensitized and ABO-incompatible high titer kidney transplantation.

    Science.gov (United States)

    Uchida, J; Machida, Y; Iwai, T; Naganuma, T; Kitamoto, K; Iguchi, T; Maeda, S; Kamada, Y; Kuwabara, N; Kim, T; Nakatani, T

    2010-12-01

    A positive crossmatch indicates the presence of donor-specific alloantibodies and is associated with a graft loss rate of >80%; anti-ABO blood group antibodies develop in response to exposure to foreign blood groups, resulting in immediate graft loss. However, a desensitization protocol for highly HLA-sensitized and ABO-incompatible high-titer kidney transplantation has not yet been established. We treated 6 patients with high (≥1:512) anti-A/B antibody titers and 2 highly HLA-sensitized patients. Our immunosuppression protocol was initiated 1 month before surgery and included mycophenolate mofetil (1 g/d) and/or low-dose steroid (methylprednisolone 8 mg/d). Two doses of the anti-CD20 antibody rituximab (150 mg/m(2)) were administered 2 weeks before and on the day of transplantation. We performed antibody removal with 6-12 sessions of plasmapheresis (plasma exchange or double-filtration plasmapheresis) before transplantation. Splenectomy was also performed on the day of transplantation. Postoperative immunosuppression followed the same regimen as ABO-compatible cases, in which calcineurin inhibitors were initiated 3 days before transplantation, combined with 2 doses of basiliximab. Of the 8 patients, 7 subsequently underwent successful living-donor kidney transplantation. Follow-up of our recipients showed that the patient and graft survival rates were 100%. Acute cellular rejection and antibody-mediated rejection episodes occurred in 1 of the 7 recipients. These findings suggest that our immunosuppression regimen consisting of rituximab infusions, splenectomy, plasmapheresis, and pharmacologic immunosuppression may prove to be effective as a desensitization protocol for highly HLA-sensitized and ABO-incompatible high-titer kidney transplantation. Copyright © 2010 Elsevier Inc. All rights reserved.

  1. Efficacy of Urtoxazumab (TMA-15 Humanized Monoclonal Antibody Specific for Shiga Toxin 2 Against Post-Diarrheal Neurological Sequelae Caused by Escherichia coli O157:H7 Infection in the Neonatal Gnotobiotic Piglet Model

    Directory of Open Access Journals (Sweden)

    Rodney A. Moxley

    2017-01-01

    Full Text Available Enterohemorrhagic Escherichia coli (EHEC is the most common cause of hemorrhagic colitis and hemolytic uremic syndrome in human patients, with brain damage and dysfunction the main cause of acute death. We evaluated the efficacy of urtoxazumab (TMA-15, Teijin Pharma Limited, a humanized monoclonal antibody against Shiga toxin (Stx 2 for the prevention of brain damage, dysfunction, and death in a piglet EHEC infection model. Forty-five neonatal gnotobiotic piglets were inoculated orally with 3 × 109 colony-forming units of EHEC O157:H7 strain EDL933 (Stx1+, Stx2+ when 22–24 h old. At 24 h post-inoculation, piglets were intraperitoneally administered placebo or TMA-15 (0.3, 1.0 or 3.0 mg/kg body weight. Compared to placebo (n = 10, TMA-15 (n = 35 yielded a significantly greater probability of survival, length of survival, and weight gain (p <0.05. The efficacy of TMA-15 against brain lesions and death was 62.9% (p = 0.0004 and 71.4% (p = 0.0004, respectively. These results suggest that TMA-15 may potentially prevent or reduce vascular necrosis and infarction of the brain attributable to Stx2 in human patients acutely infected with EHEC. However, we do not infer that TMA-15 treatment will completely protect human patients infected with EHEC O157:H7 strains that produce both Stx1 and Stx2.

  2. Neonatal antibody titers against varicella-zoster virus in relation to gestational age, birth weight, and maternal titer

    NARCIS (Netherlands)

    van der Zwet, Wil C.; Vandenbroucke-Grauls, Christina M. J. E.; van Elburg, Ruurd M.; Cranendonk, Anneke; Zaaijer, Hans L.

    2002-01-01

    OBJECTIVE: Varicella-zoster virus (VZV) can cause severe disease in premature neonates. The fetus receives protective maternal VZV-immunoglobulin G (IgG) mainly in the third trimester of pregnancy. Therefore, premature neonates are considered at risk for VZV infection. Administration of

  3. Avian Diagnostic and Therapeutic Antibodies to Viral Emerging Pathogens

    Energy Technology Data Exchange (ETDEWEB)

    David Bradley

    2011-03-31

    During the current period the following key objectives were achieved: demonstration of high titer antibody production by geese following immunization with inactived H1N1 virus; completion of the epitope mapping of West Nile Virus-specific goose antibodies and initiation of epitope mapping of H1N1 flu-specific goose antibodies; advancement in scalable purification of goose antibodies.

  4. The impact of host diet on Wolbachia titer in Drosophila.

    Directory of Open Access Journals (Sweden)

    Laura R Serbus

    2015-03-01

    Full Text Available While a number of studies have identified host factors that influence endosymbiont titer, little is known concerning environmental influences on titer. Here we examined nutrient impact on maternally transmitted Wolbachia endosymbionts in Drosophila. We demonstrate that Drosophila reared on sucrose- and yeast-enriched diets exhibit increased and reduced Wolbachia titers in oogenesis, respectively. The yeast-induced Wolbachia depletion is mediated in large part by the somatic TOR and insulin signaling pathways. Disrupting TORC1 with the small molecule rapamycin dramatically increases oocyte Wolbachia titer, whereas hyper-activating somatic TORC1 suppresses oocyte titer. Furthermore, genetic ablation of insulin-producing cells located in the Drosophila brain abolished the yeast impact on oocyte titer. Exposure to yeast-enriched diets altered Wolbachia nucleoid morphology in oogenesis. Furthermore, dietary yeast increased somatic Wolbachia titer overall, though not in the central nervous system. These findings highlight the interactions between Wolbachia and germline cells as strongly nutrient-sensitive, and implicate conserved host signaling pathways by which nutrients influence Wolbachia titer.

  5. Brown spider dermonecrotic toxin directly induces nephrotoxicity

    International Nuclear Information System (INIS)

    Chaim, Olga Meiri; Sade, Youssef Bacila; Bertoni da Silveira, Rafael; Toma, Leny; Kalapothakis, Evanguedes; Chavez-Olortegui, Carlos; Mangili, Oldemir Carlos; Gremski, Waldemiro; Dietrich, Carl Peter von; Nader, Helena B.; Sanches Veiga, Silvio

    2006-01-01

    Brown spider (Loxosceles genus) venom can induce dermonecrotic lesions at the bite site and systemic manifestations including fever, vomiting, convulsions, disseminated intravascular coagulation, hemolytic anemia and acute renal failure. The venom is composed of a mixture of proteins with several molecules biochemically and biologically well characterized. The mechanism by which the venom induces renal damage is unknown. By using mice exposed to Loxosceles intermedia recombinant dermonecrotic toxin (LiRecDT), we showed direct induction of renal injuries. Microscopic analysis of renal biopsies from dermonecrotic toxin-treated mice showed histological alterations including glomerular edema and tubular necrosis. Hyalinization of tubules with deposition of proteinaceous material in the tubule lumen, tubule epithelial cell vacuoles, tubular edema and epithelial cell lysis was also observed. Leukocytic infiltration was neither observed in the glomerulus nor the tubules. Renal vessels showed no sign of inflammatory response. Additionally, biochemical analyses showed such toxin-induced changes in renal function as urine alkalinization, hematuria and azotemia with elevation of blood urea nitrogen levels. Immunofluorescence with dermonecrotic toxin antibodies and confocal microscopy analysis showed deposition and direct binding of this toxin to renal intrinsic structures. By immunoblotting with a hyperimmune dermonecrotic toxin antiserum on renal lysates from toxin-treated mice, we detected a positive signal at the region of 33-35 kDa, which strengthens the idea that renal failure is directly induced by dermonecrotic toxin. Immunofluorescence reaction with dermonecrotic toxin antibodies revealed deposition and binding of this toxin directly in MDCK epithelial cells in culture. Similarly, dermonecrotic toxin treatment caused morphological alterations of MDCK cells including cytoplasmic vacuoles, blebs, evoked impaired spreading and detached cells from each other and from

  6. Enterotoxigenic Escherichia coli Adhesin-Toxoid Multiepitope Fusion Antigen CFA/I/II/IV-3xSTaN12S-mnLTG192G/L211A-Derived Antibodies Inhibit Adherence of Seven Adhesins, Neutralize Enterotoxicity of LT and STa Toxins, and Protect Piglets against Diarrhea.

    Science.gov (United States)

    Nandre, Rahul; Ruan, Xiaosai; Lu, Ti; Duan, Qiangde; Sack, David; Zhang, Weiping

    2018-03-01

    Enterotoxigenic Escherichia coli (ETEC) strains are a leading cause of children's diarrhea and travelers' diarrhea. Vaccines inducing antibodies to broadly inhibit bacterial adherence and to neutralize toxin enterotoxicity are expected to be effective against ETEC-associated diarrhea. 6×His-tagged adhesin-toxoid fusion proteins were shown to induce neutralizing antibodies to several adhesins and LT and STa toxins (X. Ruan, D. A. Sack, W. Zhang, PLoS One 10:e0121623, 2015, https://doi.org/10.1371/journal.pone.0121623). However, antibodies derived from His-tagged CFA/I/II/IV-2xSTa A14Q -dmLT or CFA/I/II/IV-2xSTa N12S -dmLT protein were less effective in neutralizing STa enterotoxicity and were not evaluated in vivo for efficacy against ETEC diarrhea. Additionally, His-tagged proteins are considered less desirable for human vaccines. In this study, we produced a tagless adhesin-toxoid MEFA (multiepitope fusion antigen) protein, enhanced anti-STa immunogenicity by including a third copy of STa toxoid STa N12S , and examined antigen immunogenicity in a murine model. Moreover, we immunized pregnant pigs with the tagless adhesin-toxoid MEFA protein and evaluated passive antibody protection against STa + or LT + ETEC infection in a pig challenge model. Results showed that tagless adhesin-toxoid MEFA CFA/I/II/IV-3xSTa N12S -mnLT R192G/L211A induced broad antiadhesin and antitoxin antibody responses in the intraperitoneally immunized mice and the intramuscularly immunized pigs. Mouse and pig serum antibodies significantly inhibited adherence of seven colonization factor antigen (CFA) adhesins (CFA/I and CS1 to CS6) and effectively neutralized both toxins. More importantly, suckling piglets born to the immunized mothers acquired antibodies and were protected against STa + ETEC and LT + ETEC diarrhea. These results indicated that tagless CFA/I/II/IV-3xSTa N12S -mnLT R192G/L211A induced broadly protective antiadhesin and antitoxin antibodies and demonstrate that this adhesin

  7. Immunogenicity of a cholera toxin B subunit Porphyromonas gingivalis fimbrial antigen fusion protein expressed in E. coli.

    Science.gov (United States)

    Kim, Tae-Geum; Huy, Nguyen-Xuan; Kim, Mi-Young; Jeong, Dong-Keun; Jang, Yong-Suk; Yang, Moon-Sik; Langridge, William H R; Lee, Jin-Yong

    2009-02-01

    The gram-negative anaerobic oral bacterium Porphyromonas gingivalis initiates periodontal disease through fimbrial attachment to saliva-coated oral surfaces. To study the effects of immunomodulation on enhancement of subunit vaccination, the expression in E. coli and immunogenicity of P. gingivalis fimbrial protein (FimA) linked to the C-terminus of the cholera toxin B subunit (CTB) were investigated. Complementary DNAs encoding the P. gingivalis 381 fimbrillin protein sequence FimA1 (amino acid residues 1-200) and FimA2 (amino acid residues 201-337) were cloned into an E. coli expression vector downstream of a cDNA fragment encoding the immunostimulatory CTB. CTB-FimA1 and CTB-FimA2 fusion proteins synthesized in E. coli BL21 (DE3) cells were purified under denaturing conditions by Ni2+-NTA affinity column chromatography. Renaturation of the CTB-FimA1 and CTB-FimA2 fusion proteins, permitted identification of CTB-FimA pentamers and restored CTB binding activity to GM1-ganglioside to provide a biologically active CTB-FimA fusion protein. Mice orally inoculated with purified CTB-FimA1 or CTB-FimA2 fusion proteins generated measurable FimA1 and FimA2 IgG antibody titers, while no serum fimbrial IgG antibodies were detected when mice were inoculated with FimA1 or FimA2 proteins alone. Immunoblot analysis confirmed that sera from mice immunized with CTB linked to FimA1 or FimA2 contained antibodies specific for P. gingivalis fimbrial proteins. In addition, mice immunized with FimA2 or CTB-FimA2 generated measurable intestinal IgA titers indicating the presence of fimbrial antibody class switching. Further, mice orally immunized with CTB-FimA1 generated higher IgA antibody titers than mice inoculated with FimA1 alone. The experimental data show that the immunostimulatory molecule CTB enhances B cell-mediated immunity against linked P. gingivalis FimA fusion proteins, in comparison to immunization with FimA protein alone. Thus, linkage of CTB to P. gingivalis fimbrial

  8. Decay of maternal antibodies in broiler chickens.

    Science.gov (United States)

    Gharaibeh, Saad; Mahmoud, Kamel

    2013-09-01

    The objective of this study was to determine the decay rate of maternal antibodies against major broiler chicken pathogens. A total of 30 one-day-old broiler chicks were obtained from a commercial hatchery and reared in isolation. These chicks were retrieved from a parent flock that received a routine vaccination program. Chicks were bled at hatch and sequentially thereafter every 5 d through 30 d of age. Maternal antibody titers were measured by ELISA for avian encephalomyelitis (AEV), avian influenza virus (AIV), chicken anemia virus (CAV), infectious bursal disease virus (IBDV), infectious bronchitis virus (IBV), infectious laryngotracheitis virus (ILTV), Mycoplasma gallisepticum (MG), Mycoplasma synoviae (MS), and reovirus (Reo). Maternal antibody titers for Newcastle disease virus (NDV) were measured using a hemagglutination inhibition test. Half-life estimates of maternal antibody titers were 5.3, 4.2, 7, 5.1, 3.9, 3.8, 4.9, 4.1, 6.3, and 4.7 d for AEV, AIV, CAV, IBDV, IBV, ILTV, MG, MS, NDV, and Reo, respectively. The statistical analysis revealed significant differences among half-lives of maternal antibody titers against certain pathogens. Furthermore, all maternal antibody titers were depleted by 10 d of age except for IBDV.

  9. Staphylococcus hyicus exfoliative toxin: Purification and demonstration of antigenic diversity among toxins from virulent strains

    DEFF Research Database (Denmark)

    Andresen, Lars Ole; Bille-Hansen, Vivi; Wegener, Henrik Caspar

    1997-01-01

    The exfoliative toxin produced by Staphylococcus hyicus strain 1289D-88 was purified as a single protein of approximately 30 kDa. Extracellular proteins of S. hyicus grown under small scale fermentation conditions were precipitated with ammonium sulfate. Separation of proteins was performed...... of 0.5 mM CuSO4 to the purified toxin resulted in more intense skin alterations comparable to lesions caused by precipitated culture supernatant diluted 1:10. These results indicated that the activity of the exfoliative toxin was dependent on the presence of Cu2+. Polyclonal and monoclonal antibodies...

  10. Pros and cons of different therapeutic antibody formats for recombinant antivenom development

    DEFF Research Database (Denmark)

    Laustsen, Andreas H.; Gutiérrez, José María; Knudsen, Cecilie

    2018-01-01

    Antibody technologies are being increasingly applied in the field of toxinology. Fuelled by the many advances in immunology, synthetic biology, and antibody research, different approaches and antibody formats are being investigated for the ability to neutralize animal toxins. These different...

  11. Reactions with Antisera and Pathological Effects of Staphylococcus aureus Gamma-Toxin in the Cornea.

    Science.gov (United States)

    Bierdeman, Michael A; Torres, Angela M; Caballero, Armando R; Tang, Aihua; O'Callaghan, Richard J

    2017-08-01

    This study analyzed the toxicity of purified gamma-toxin from Staphylococcus aureus and the protectiveness of antisera to gamma-toxin in the rabbit cornea. Gamma-toxin was purified from cultures of alpha-toxin deficient S. aureus strain Newman Δhla. Antisera to native gamma-toxin (Hlg) were produced in rabbits. These antisera and a commercial polyclonal antibody to recombinant HlgB (rHlgB) were analyzed for specificity and toxin neutralization. Heat-inactivated gamma-toxin, active gamma-toxin either alone or with antisera or with commercial antibody to rHlgB, was injected into the rabbit cornea to observe the pathological effects using slit lamp examination scoring (SLE) and histological analyses. Eyes with intrastromal injection of gamma-toxin developed SLE scores that were significantly higher than eyes injected with heat-inactivated gamma-toxin (p ≤ 0.003). Slit lamp and histological examination of eyes revealed that gamma-toxin injected into the cornea mediated conjunctival injection and chemosis, iritis, fibrin accumulation in the anterior chamber, and polymorphonuclear neutrophil infiltration of the cornea and iris. Also, eyes injected with gamma-toxin plus antisera to native whole gamma-toxin or HlgB, but not with commercial antibody to rHlgB, yielded significantly lower SLE scores than eyes injected with gamma-toxin alone (p ≤ 0.003). This study illustrates that S. aureus gamma-toxin is capable of causing significant corneal pathology. Furthermore, the use of polyclonal antisera specific for native gamma-toxin was found to inhibit the damaging effects of the toxin in the rabbit cornea.

  12. MERS-CoV Antibody Responses 1 Year after Symptom Onset, South Korea, 2015.

    Science.gov (United States)

    Choe, Pyoeng Gyun; Perera, R A P M; Park, Wan Beom; Song, Kyoung-Ho; Bang, Ji Hwan; Kim, Eu Suk; Kim, Hong Bin; Ko, Long Wei Ronald; Park, Sang Won; Kim, Nam-Joong; Lau, Eric H Y; Poon, Leo L M; Peiris, Malik; Oh, Myoung-Don

    2017-07-01

    We investigated the kinetics of the Middle East respiratory syndrome coronavirus (MERS-CoV) neutralizing and spike protein antibody titers over the course of 1 year in 11 patients who were confirmed by reverse transcription PCR to have been infected during the outbreak in South Korea in 2015. Robust antibody responses were detected in all survivors who had severe disease; responses remained detectable, albeit with some waning, for <1 year. The duration of viral RNA detection (but not viral load) in sputum significantly correlated with the antibody response magnitude. The MERS S1 ELISA antibody titers correlated well with the neutralizing antibody response. Antibody titers in 4 of 6 patients who had mild illness were undetectable even though most had evidence of pneumonia. This finding implies that MERS-CoV seroepidemiologic studies markedly underestimate the extent of mild and asymptomatic infection. Obtaining convalescent-phase plasma with high antibody titers to treat MERS will be challenging.

  13. How Can HIV-Type-1-Env Immunogenicity Be Improved to Facilitate Antibody-Based Vaccine Development?

    NARCIS (Netherlands)

    Klasse, Per Johan; Sanders, Rogier W.; Cerutti, Andrea; Moore, John P.

    2012-01-01

    No vaccine candidate has induced antibodies (Abs) that efficiently neutralize multiple primary isolates of HIV-1. Preexisting high titers of neutralizing antibodies (NAbs) are essential, because the virus establishes infection before anamnestic responses could take effect. HIV-1 infection elicits

  14. Correlation between alanine aminotransferase level, HCV-RNA titer ...

    African Journals Online (AJOL)

    Reham Al Swaff

    2012-04-04

    Apr 4, 2012 ... Abstract The relationship of serum alanine aminotransferase (ALT) level and viral replication to liver damage in chronic hepatitis C virus (HCV) patients remains unclear. The aim of the present study was to determine whether the stage of fibrosis correlates with HCV-. RNA titer and/or serum ALT level in ...

  15. An improved plating assay for determination of phage titer

    African Journals Online (AJOL)

    RACHEL

    antibiotics to control bacterial infections in swine (Thacker,. 2014). Phage therapy is re-valued by researchers to combat the growing menace of antibiotic-resistant infections (Torres-Barceló and Hochberg, 2016). Determination of phage titer in a sample is a key step in the study of the phage involved. It is very important to.

  16. Antibody Production with Synthetic Peptides.

    Science.gov (United States)

    Lee, Bao-Shiang; Huang, Jin-Sheng; Jayathilaka, Lasanthi P; Lee, Jenny; Gupta, Shalini

    2016-01-01

    Peptides (usually 10-20 amino acid residues in length) can be used as effectively as proteins in raising antibodies producing both polyclonal and monoclonal antibodies routinely with titers higher than 20,000. Peptide antigens do not function as immunogens unless they are conjugated to proteins. Production of high quality antipeptide antibodies is dependent upon peptide sequence selection, the success of peptide synthesis, peptide-carrier protein conjugation, the humoral immune response in the host animal, the adjuvant used, the peptide dose administered, the injection method, and the purification of the antibody. Peptide sequence selection is probably the most critical step in the production of antipeptide antibodies. Although the process for designing peptide antigens is not exact, several guidelines and computational B-cell epitope prediction methods can help maximize the likelihood of producing antipeptide antibodies that recognize the protein. Antibodies raised by peptides have become essential tools in life science research. Virtually all phospho-specific antibodies are now produced using phosphopeptides as antigens. Typically, 5-20 mg of peptide is enough for antipeptide antibody production. It takes 3 months to produce a polyclonal antipeptide antibody in rabbits that yields ~100 mL of serum which corresponds to ~8-10 mg of the specific antibody after affinity purification using a peptide column.

  17. Radiolabelling of cholera toxin

    International Nuclear Information System (INIS)

    Santos, R.G.; Neves, Nicoli M.J.; Abdalla, L.F.; Brandao, R.L.; Etchehebehere, L.; Lima, M.E. de; Nicoli, J.R.

    1999-01-01

    Binding of cholera toxin to ganglioside receptors of enterocyte microvilli catalyzes the activation of adenylate cyclase causing a rise in cAMP which final result is a copious diarrhea. Saccharomyces boulardii, a nonpathogenic yeast has been used to prevent diarrhea. Although the antidiarrheic properties of S. boulardii are widely recognized, this yeast has been used on empirical basis, and the mechanism of this protective effect is unknown. The addition of cholera toxin to S. boulardii induces the raising of cAMP that triggers the activation of neutral trehalase. This suggests that toxin specifically binding to cells, is internalized and active the protein phosphorylation cascade. Our objective is labeling the cholera toxin to verify the presence of binding sites on yeast cell surfaces for the cholera toxin. Cholera toxin was radiolabelled with Na 125 I by a chloramine-T method modified from Cuatrecasas and Griffiths et alii. The 125 I-Cholera toxin showed a specific radioactivity at about 1000 cpm/fmol toxin. Biological activity of labeled cholera toxin measured by trehalase activation was similar to the native toxin. (author)

  18. Radiolabelling of cholera toxin

    Energy Technology Data Exchange (ETDEWEB)

    Santos, R.G.; Neves, Nicoli M.J. [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN), Belo Horizonte, MG (Brazil); Abdalla, L.F.; Brandao, R.L.; Etchehebehere, L. [Ouro Preto Univ., MG (Brazil). Escola de Farmacia. Lab. de Fisiologia e Bioquimica de Microorganismos; Lima, M.E. de [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Inst. de Ciencias Biologicas. Dept. de Bioquimica e Imunologia; Nicoli, J.R. [Minas Gerais Univ., Belo Horizonte, MG (Brazil). Inst. de Ciencias Biologicas. Dept. de Microbiologia

    1999-11-01

    Binding of cholera toxin to ganglioside receptors of enterocyte microvilli catalyzes the activation of adenylate cyclase causing a rise in cAMP which final result is a copious diarrhea. Saccharomyces boulardii, a nonpathogenic yeast has been used to prevent diarrhea. Although the antidiarrheic properties of S. boulardii are widely recognized, this yeast has been used on empirical basis, and the mechanism of this protective effect is unknown. The addition of cholera toxin to S. boulardii induces the raising of cAMP that triggers the activation of neutral trehalase. This suggests that toxin specifically binding to cells, is internalized and active the protein phosphorylation cascade. Our objective is labeling the cholera toxin to verify the presence of binding sites on yeast cell surfaces for the cholera toxin. Cholera toxin was radiolabelled with Na {sup 125} I by a chloramine-T method modified from Cuatrecasas and Griffiths et alii. The {sup 125} I-Cholera toxin showed a specific radioactivity at about 1000 cpm/fmol toxin. Biological activity of labeled cholera toxin measured by trehalase activation was similar to the native toxin. (author) 5 refs., 3 figs.; e-mail: nevesmj at urano.cdtn.br

  19. The immunogenicity of fusion protein linking the carboxyl terminus of the B subunit of Shiga toxin 2 to the B subunit of E. coli heat-labile enterotoxin.

    Science.gov (United States)

    Ran, Xue Qin; Wang, Hong Zhen; Liu, Jin Juan; Li, Sheng; Wang, Jia Fu

    2008-02-05

    To augment the immunogenicity of the subunit B of Shiga toxin (Stx2e B) produced by Escherichia coli and protect piglets from edema disease in china, a fusion gene was constructed consisting of Stx2e B genetically linked at the N-terminus of the B subunit of heat-labile enterotoxin (LTB) in a translational fusion. After being induced with IPTG, the expressed fusion protein of Stx2e B-LTB was about 8.8% of total proteins, approximately 13 microg/ml of the bacteria culture. The Stx2e B-LTB fusion protein was found to be nontoxic to Vero cells at the dose higher than 1 microg/ml and to mice less than 100 microg/ml. Antibody titer against the fusion protein Stx2e B-LTB was 1:76,800, much higher than that of the recombinant Stx2e B protein (1:12,800) alone. All of the mice immunized with the Stx2e B-LTB fusion protein survived when challenged with a lethal dose (LD) of Stx2e toxin. The results showed that the poor immunogenicity of Stx2e B was overcome by conjugating the stx2e B to ltB. The immunogenicity of the constructed fusion protein Stx2e B-LTB in the present study was highly qualified to protect animals against Shiga toxin produced from Shiga toxin-producing Escherichia coli (STEC). The fusion protein of Stx2e B-LTB could be a candidate for a vaccine against edema disease and post-weaning diarrhea simultaneously in piglets.

  20. The association between serological titers in infectious bovine rhinotracheitis virus, bovine virus diarrhea virus, parainfluenza-3 virus, respiratory syncytial virus and treatment for respiratory disease in Ontario feedlot calves.

    OpenAIRE

    Martin, S W; Bohac, J G

    1986-01-01

    A seroepidemiological study of the association between antibody titers to infectious bovine rhinotracheitis, parainfluenza-3, bovine virus diarrhea and bovine respiratory syncytial viruses, and treatment for bovine respiratory disease was conducted. A total of 322 calves from five different groups were bled on arrival, then one month later all cases (cattle treated for bovine respiratory disease) were rebled together with an equal number of controls (cattle not treated for any disease). Titer...

  1. Impact of Uniform Methods on Interlaboratory Antibody Titration Variability: Antibody Titration and Uniform Methods.

    Science.gov (United States)

    Bachegowda, Lohith S; Cheng, Yan H; Long, Thomas; Shaz, Beth H

    2017-01-01

    -Substantial variability between different antibody titration methods prompted development and introduction of uniform methods in 2008. -To determine whether uniform methods consistently decrease interlaboratory variation in proficiency testing. -Proficiency testing data for antibody titration between 2009 and 2013 were obtained from the College of American Pathologists. Each laboratory was supplied plasma and red cells to determine anti-A and anti-D antibody titers by their standard method: gel or tube by uniform or other methods at different testing phases (immediate spin and/or room temperature [anti-A], and/or anti-human globulin [AHG: anti-A and anti-D]) with different additives. Interlaboratory variations were compared by analyzing the distribution of titer results by method and phase. -A median of 574 and 1100 responses were reported for anti-A and anti-D antibody titers, respectively, during a 5-year period. The 3 most frequent (median) methods performed for anti-A antibody were uniform tube room temperature (147.5; range, 119-159), uniform tube AHG (143.5; range, 134-150), and other tube AHG (97; range, 82-116); for anti-D antibody, the methods were other tube (451; range, 431-465), uniform tube (404; range, 382-462), and uniform gel (137; range, 121-153). Of the larger reported methods, uniform gel AHG phase for anti-A and anti-D antibodies had the most participants with the same result (mode). For anti-A antibody, 0 of 8 (uniform versus other tube room temperature) and 1 of 8 (uniform versus other tube AHG), and for anti-D antibody, 0 of 8 (uniform versus other tube) and 0 of 8 (uniform versus other gel) proficiency tests showed significant titer variability reduction. -Uniform methods harmonize laboratory techniques but rarely reduce interlaboratory titer variance in comparison with other methods.

  2. Detection of Shiga Toxins by Lateral Flow Assay

    OpenAIRE

    Ching, Kathryn H.; He, Xiaohua; Stanker, Larry H.; Lin, Alice V.; McGarvey, Jeffery A.; Hnasko, Robert

    2015-01-01

    Shiga toxin-producing Escherichia coli (STEC) produce shiga toxins (Stxs) that can cause human disease and death. The contamination of food products with STEC represents a food safety problem that necessitates rapid and effective detection strategies to mitigate risk. In this manuscript, we report the development of a colorimetric lateral flow assay (LFA) for the rapid detection of Stxs in <10 min using a pair of monoclonal antibodies that bind epitopes common to Stx1 and six Stx2 variants...

  3. An imaging surface plasmon resonance biosensor assay for the detection of T-2 toxin and masked T-2 toxin-3-glucoside in wheat

    Science.gov (United States)

    A sensitive, rapid, and reproducible imaging surface plasmon resonance (iSPR) biosensor assay was developed to detect T-2 toxin and T-2 toxin-3-glucoside (T2-G) in wheat. In this competitive assay, an amplification strategy was used after conjugating a secondary antibody (Ab2) with gold nanoparticle...

  4. Array biosensor for detection of toxins

    Science.gov (United States)

    Ligler, Frances S.; Taitt, Chris Rowe; Shriver-Lake, Lisa C.; Sapsford, Kim E.; Shubin, Yura; Golden, Joel P.

    2003-01-01

    The array biosensor is capable of detecting multiple targets rapidly and simultaneously on the surface of a single waveguide. Sandwich and competitive fluoroimmunoassays have been developed to detect high and low molecular weight toxins, respectively, in complex samples. Recognition molecules (usually antibodies) were first immobilized in specific locations on the waveguide and the resultant patterned array was used to interrogate up to 12 different samples for the presence of multiple different analytes. Upon binding of a fluorescent analyte or fluorescent immunocomplex, the pattern of fluorescent spots was detected using a CCD camera. Automated image analysis was used to determine a mean fluorescence value for each assay spot and to subtract the local background signal. The location of the spot and its mean fluorescence value were used to determine the toxin identity and concentration. Toxins were measured in clinical fluids, environmental samples and foods, with minimal sample preparation. Results are shown for rapid analyses of staphylococcal enterotoxin B, ricin, cholera toxin, botulinum toxoids, trinitrotoluene, and the mycotoxin fumonisin. Toxins were detected at levels as low as 0.5 ng mL(-1).

  5. Recycling old screen-printed electrodes with newly designed plastic antibodies on the wall of carbon nanotubes as sensory element for in situ detection of bacterial toxins in water

    OpenAIRE

    Queirós, Raquel B.; Guedes, A.; Marques, P.V.S.; Noronha, João P. C.; Sales, M. Goreti F.

    2012-01-01

    Using low cost portable devices that enable a single analytical step for screening environmental contaminants is today a demanding issue. This concept is here tried out by recycling screen-printed electrodes that were to be disposed of and by choosing as sensory element a low cost material offering specific response for an environmental contaminant. Microcystins (MCs) were used as target analyte, for being dangerous toxins produced by cyanobacteria released into water bodies. The ...

  6. Fibrinogen titer and glycemic status in women using contraceptives

    International Nuclear Information System (INIS)

    Syed, S.; Qureshi, M.A.

    2002-01-01

    Objective: To assess the coagulation and glycemic status in Pakistani women using contraceptives. Design: The study was conducted prospectively on 70 women and compared with 10 age-matched controls. Place and Duration of Study: The study was conducted at Karachi. Period of study was 18 month. Subjects and Methods: Eighty women aged between 20-45 years selected from low socioeconomic class and poor family background were categorized in control (n=10) and oral and injectable contraceptive users (n = 70). The contraceptives used were tablet Lofemenal, injection Norigest and Norplant implant. Their blood was tested for fibrinogen titer and random blood glucose. Results: There was no appreciable difference either in fibrinogen titer or plasma glucose levels in injectable users as compared to controls, but increased incidence of high fibrinogen titer and borderline blood glucose was observed in oral contraceptive users 25% and 20 % respectively. Conclusion: It was concluded that long-term use of oral contraceptives (> 3 years) might increase the thrombotic tendency and elevate the plasma glucose levels especially in women above 30 years of age. (author)

  7. Measles Antibodies in Mother-Infant Dyads in Tianjin, China.

    Science.gov (United States)

    Boulton, Matthew L; Wang, Xiexiu; Wagner, Abram L; Zhang, Ying; Carlson, Bradley F; Gillespie, Brenda W; Ding, Yaxing

    2017-11-27

    Many measles cases in Tianjin, China, occur in infants whose mothers were born after widespread vaccination programs. We assessed age-specific decreases in maternal measles antibodies in infants and examined maternal and infant characteristics in relation to infant antibody titers. Infant and mother dyads were enrolled from a sample of immunization clinics in all Tianjin districts. Participants' antibody titers were measured from dried blood spots. A multivariable log-linear model regressed infant antibody titers onto infant and mother characteristics. Among 551 infants aged ≤8 months, protective levels of measles antibodies were observed in infants whose mothers had measles titers ≥800 IU/mL (mean antibody titer, 542.5 IU/mL) or 400 to measles and an accordingly low efficiency of transplacental transmission to a fetus. Current vaccination programs, which target children aged 8 months through adolescence may be ineffective in controlling transmission of measles to infants. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  8. Prevalence of recovirus-neutralizing antibodies in human serum samples.

    Science.gov (United States)

    Farkas, Tibor; Wong Ping Lun, Cindy

    2014-08-01

    To investigate recovirus infections and their association with zoonosis, the prevalence of the virus-neutralizing antibody against three recovirus serotypes was tested in the general population and in zookeepers. Neutralizing antibodies were detected in a significantly higher number of zookeepers than in the general population but with significantly lower titers than in macaques. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  9. Comparison of detection methods for antibodies to boar spermatozoa

    African Journals Online (AJOL)

    The different methods varied in their sensitivity to determination of sperm antibody titers. The ELISA was the most sensitive of the methods. The ELISA and Protein A agglutination were the most suitable in terms of specificity and repeatability for sperm antibody detection in swine. (Tropical Veterinarian: 2003 21(1): 1-13) ...

  10. A system for improved production titers in fermentations

    DEFF Research Database (Denmark)

    2017-01-01

    The invention provides a genetically modified micro-organism for intracellular biosynthesis of a cellular metabolite, comprising a synthetic error correction system having a penalty gene, whose expression leads to arrested growth or cell death (e.g. a toxin gene) in combination with a survival gene...

  11. Urine antibody against human cancer antigen NY-ESO-1

    OpenAIRE

    Jäger, Dirk; Stockert, Elisabeth; Karbach, Julia; Herrlinger, Kristina; Atmaca, Akin; Arand, Michael; Chen, Yao-Tseng; Gnjatic, Sacha; Old, Lloyd J; Knuth, Alexander; Jäger, Elke

    2002-01-01

    NY-ESO-1 is one of the most immunogenic tumor antigens known to date. Spontaneous humoral and cellular immune responses against NY-ESO-1 are detected in a substantial proportion of patients with NY-ESO-1 positive cancers. NY-ESO-1 serum antibody is dependent on the presence of NY-ESO-1+ cancer cells, and antibody titers correlate with the clinical development of the disease. NY-ESO-1 serum antibody is associated with detectable NY-ESO-1-specific CD8+ T cell reactivity. High titers of NY-ESO-1...

  12. Measles Virus Neutralizing Antibodies in Intravenous Immunoglobulins: Is an Increase by Revaccination of Plasma Donors Possible?

    Science.gov (United States)

    Modrof, Jens; Tille, Björn; Farcet, Maria R; McVey, John; Schreiner, Jessica A; Borders, Charles M; Gudino, Maria; Fitzgerald, Peter; Simon, Toby L; Kreil, Thomas R

    2017-11-15

    We report a screen of plasma donors confirming that widespread use of childhood measles vaccination since 1963 resulted in a decrease in average measles virus antibody titers among plasma donors, which is reflected in intravenous immunoglobulins (IVIGs). The measles virus antibody titer, however, is a potency requirement for IVIGs, as defined in a Food and Drug Administration regulation. To mitigate the decline in measles virus antibody titers in IVIGs and to ensure consistent product release, revaccination of plasma donors was investigated as a means to boost titers. However, revaccination-induced titer increases were only about 2-fold and short-lived. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  13. Evidence of the protective immunogenicity of native and recombinant Clostridium haemolyticum phospholipase C (beta toxin) in guinea pigs.

    Science.gov (United States)

    Hauer, Paul J; Yeary, Teresa J; Rosenbusch, Ricardo F

    2006-01-12

    The immunogenic effects of the beta toxin of Clostridium haemolyticum were investigated in guinea pigs. Guinea pigs passively immunized with toxin-neutralizing monoclonal antibodies were protected from a 100 LD(50) spore challenge that was lethal to nonvaccinated controls. Guinea pigs actively immunized with varying doses of immunoaffinity-purified native beta toxin were similarly protected. In a third experiment, a recombinant toxoid was prepared from E. coli expressing the beta toxin gene. Guinea pigs immunized three times with recombinant toxoid also were protected against challenge. In each experiment, protection was correlated to the presence of anti-beta toxin antibodies in the serum. Taken together, these results indicate that a neutralizing antibody response to the beta toxin is a key component of protective immunity to C. haemolyticum in guinea pigs.

  14. Component Analysis of Sweet BV and Clinical Trial on Antibody Titer and Allergic Reactions

    OpenAIRE

    Ki Rok, Kwon; Suk Ho, Choi; Bae Chun Cha

    2006-01-01

    Objectives : The aim of this study was to observe prevention of allergic reactions of Sweet Bee Venom (removing enzyme components from Bee Venom). Methods : Content analysis of Sweet Bee Venom and Bee Venom was rendered using HPLC method and characterization of Anti-Sweet Bee Venom in Rabbit Serum. Clinical observation was conducted for inducement of allergic responses to Sweet BV. Results : 1. Analyzing melittin content using HPLC, Sweet BV contained 34.9% more melittin than Bee venom ...

  15. A dermatomyositis and scleroderma overlap syndrome with a remarkable high titer of anti-exosome antibodies

    Directory of Open Access Journals (Sweden)

    E. Avalos-Díaz

    2011-09-01

    Full Text Available In 1972, Sharp et al described the mixed connective tissue disease; such a description corresponded to an apparently distinct rheumatic disease syndrome associated to U1RNP, which is an extractable nuclear antigen or ENA (1. After this clever description, different overlap syndromes that did not meet the EMTC criteria were described. Conceptually Alarcón-Segovia coined the term of “shared autoimmunity”, which was defined by the presence of two or more data compatible with autoimmune disease; such category of disease describes signs or symptoms of certain autoimmune connective diseases, for instance Rupus corresponds to lupus erythematosus associated...

  16. Microalgal toxin(s): characteristics and importance

    African Journals Online (AJOL)

    Prokaryotic and eukaryotic microalgae produce a wide array of compounds with biological activities. These include antibiotics, algicides, toxins, pharmaceutically active compounds and plant growth regulators. Toxic microalgae, in this sense, are common only among the cyanobacteria and dinoflagellates. The microalgal ...

  17. Detection of seven virulence and toxin genes of Campylobacter jejuni isolates from Danish turkeys by PCR and cytolethal distending toxin production of the isolates.

    Science.gov (United States)

    Bang, Dang Duong; Borck, Birgitte; Nielsen, Eva Møller; Scheutz, Flemming; Pedersen, Karl; Madsen, Mogens

    2004-10-01

    A total of 117 Campylobacter jejuni isolates from Danish turkeys were tested for the presence of seven virulence and toxin genes by PCR. One hundred seventeen (100%) isolates were positive for flaA, cadF, and ceuE gene primers. One hundred three (88%) isolates were positive for cdt gene cluster PCR detection (cdt gene cluster-PCR), whereas 101 (86.3%), 102 (87.2%), and 110 (94%) isolates were positive for cdtA-, cdtB-, and cdtC-PCR, respectively. Only 39 (33.3%) isolates were positive for virB11. Of 117 isolates, 114 (97.4%) produced cytolethal distending toxin (CDT) in Vero cell assays, 105 (89.7%) in Colon 205 assays, and 109 (93.2%) in chicken embryo cell assays. The CDT titers were determined in Vero cell assays. Of 117 isolates, 50 (42.7%) produced a CDT titer of 1:100, 29 (24.8%) of 1:50, and 27 (23%) of 1:5 to 1:10; 8 (6.8%) produced a CDT titer at undiluted supernatants and 3 (2.6%) produced no toxin. Twenty-nine C. jejuni isolates that were PCR negative for one or more individual cdt toxin genes also produced low or no CDT toxin. The high prevalence of the seven virulence and toxin genes demonstrates that these putative pathogenic determinants are widespread among Campylobacter isolates from turkeys and calls for further investigation for the elimination of Campylobacter infection in industrial turkey production and in industrial food chains.

  18. Long-term humoral antibody responses by various serologic tests in pigs orally inoculated with oocysts of four strains of Toxoplasma gondii

    DEFF Research Database (Denmark)

    Dubey, J.P.; Andrews, C.D.; Thulliez, P.

    1997-01-01

    Antibody titers to Toxoplasma gondii were determined in 16 pigs orally inoculated with 1000 or 10000 oocysts of one of the four strains (GT-1, ME-49, TS-2, TC-2) of T. gondii. Pigs were euthanized on postinoculation days 103-875 and their tissues were bioassayed for T. gondii. Antibody titers wer...

  19. Passive transfer of maternal antibodies to West Nile virus in flamingo chicks (Phoenicopterus chilensis and Phoenicopterus ruber ruber).

    Science.gov (United States)

    Baitchman, Eric J; Tlusty, Michael F; Murphy, Hayley W

    2007-06-01

    Passive transfer of maternal antibodies against West Nile virus (WNV) was studied in a captive population of Chilean (Phoenicopterus chilensis) and Caribbean flamingos (Phoenicopterus ruber ruber). Transfer of WNV antibodies from hens to chicks was documented and measured by plaque-reduction neutralization test. Hen titers were significantly correlated to chick titers. Mean half-life of maternal WNV antibodies was 13.4 days in chicks for which half-life was measurable.

  20. A Simple and Specific Noncompetitive ELISA Method for HT-2 Toxin Detection

    Directory of Open Access Journals (Sweden)

    Henri O. Arola

    2017-04-01

    Full Text Available We developed an HT-2 toxin-specific simple ELISA format with a positive read-out. The assay is based on an anti-immune complex (IC scFv antibody fragment, which is genetically fused with alkaline phosphatase (AP. The anti-IC antibody specifically recognizes the IC between a primary anti-HT-2 toxin Fab fragment and an HT-2 toxin molecule. In the IC ELISA format, the sample is added together with the scFv-AP antibody to the ELISA plate coated with the primary antibody. After 15 min of incubation and a washing step, the ELISA response is read. A competitive ELISA including only the primary antibody recognizes both HT-2 and T-2 toxins. The anti-IC antibody makes the assay specific for HT-2 toxin, and the IC ELISA is over 10 times more sensitive compared to the competitive assay. Three different naturally contaminated matrices: wheat, barley and oats, were used to evaluate the assay performance with real samples. The corresponding limits of detection were 0.3 ng/mL (13 µg/kg, 0.1 ng/mL (4 µg/kg and 0.3 ng/mL (16 µg/kg, respectively. The IC ELISA can be used for screening HT-2 toxin specifically and in relevant concentration ranges from all three tested grain matrices.

  1. Microangiopathic antiphospholipid antibody syndrome due to anti-phosphatidylserine/prothrombin complex IgM antibody.

    Science.gov (United States)

    Senda, Yumi; Ohta, Kazuhide; Yokoyama, Tadafumi; Shimizu, Masaki; Furuichi, Kengo; Wada, Takashi; Yachie, Akihiro

    2017-03-01

    Herein we describe a case of microangiopathic antiphospholipid syndrome (MAPS) due to anti-phosphatidylserine/prothrombin complex (aPS/PT) IgM antibody successfully treated with rituximab. A significant correlation was observed between the clinical course and the aPS/PT IgM antibody titer, which can rise earlier before the appearance of clinical symptoms. Rituximab can be safely and effectively used for MAPS. Although detection of only aPS/PT IgM antibody is rare, aPS/PT IgM antibody might be associated with the pathogenesis of MAPS and might be a useful marker of disease activity. © 2017 Japan Pediatric Society.

  2. High-throughput epitope profiling of snake venom toxins

    DEFF Research Database (Denmark)

    Engmark, Mikael; Andersen, Mikael Rørdam; Laustsen, Andreas Hougaard

    Insight into the molecular details of polyclonal antivenom antibody specificity is a prerequisite for accurate prediction of cross-reactivity and can provide a basis for design of novel antivenoms. In this work, a highthroughput approach was applied to characterize linear elements in epitopes in 82...... toxins from four African mamba and three neurotoxic cobra snakes obtained from public databases....

  3. Detection of seven virulence and toxin genes of Campylobacter jejuni isolates from Danish turkeys by PCR and cytolethal distending toxin production of the isolates

    DEFF Research Database (Denmark)

    Bang, Dang Duong; Borck, Birgitte; Nielsen, Eva Møller

    2004-01-01

    A total of 117 Campylobacter jejuni isolates from Danish turkeys were tested for the presence of seven virulence and toxin genes by PCR. One hundred seventeen (100%) isolates were positive for flaA, cadF, and ceuE gene primers. One hundred three (88%) isolates were positive for cdt gene cluster PCR.......7%) in Colon 205 assays, and 109 (93.2%) in chicken embryo cell assays. The CDT titers were determined in Vero cell assays. Of 117 isolates, 50 (42.7%) produced a CDT titer of 1:100, 29 (24.8%) of 1:50, and 27 (23%) of 1:5 to 1:10; 8 (6.8%) produced a CDT titer at undiluted supernatants and 3 (2.6%) produced...

  4. Polyclonal Antibody Therapies for Clostridium difficile Infection

    Directory of Open Access Journals (Sweden)

    Michael R. Simon

    2014-10-01

    Full Text Available Clostridium difficile infection has emerged as a growing worldwide health problem. The colitis of Clostridium difficile infection results from the synergistic action of C. difficile secreted toxins A and B upon the colon mucosa. A human monoclonal IgG anti-toxin has demonstrated the ability in combination therapy to reduce mortality in C. difficile challenged hamsters. This antibody is currently in a clinical trial for the treatment of human Clostridium difficile infection. More than one group of investigators has considered using polyclonal bovine colostral antibodies to toxins A and B as an oral passive immunization. A significant proportion of the healthy human population possesses polyclonal antibodies to the Clostridium difficile toxins. We have demonstrated that polyclonal IgA derived from the pooled plasma of healthy donors possesses specificity to toxins A and B and can neutralize these toxins in a cell-based assay. This suggests that secretory IgA prepared from such pooled plasma IgA may be able to be used as an oral treatment for Clostridium difficile infection.

  5. Molecular Characterization of the Vacuolating Autotransporter Toxin in Uropathogenic Escherichia coli.

    Science.gov (United States)

    Nichols, Katie B; Totsika, Makrina; Moriel, Danilo G; Lo, Alvin W; Yang, Ji; Wurpel, Daniël J; Rossiter, Amanda E; Strugnell, Richard A; Henderson, Ian R; Ulett, Glen C; Beatson, Scott A; Schembri, Mark A

    2016-05-15

    The vacuolating autotransporter toxin (Vat) contributes to uropathogenic Escherichia coli (UPEC) fitness during systemic infection. Here, we characterized Vat and investigated its regulation in UPEC. We assessed the prevalence of vat in a collection of 45 UPEC urosepsis strains and showed that it was present in 31 (68%) of the isolates. The isolates containing the vat gene corresponded to three major E. coli sequence types (ST12, ST73, and ST95), and these strains secreted the Vat protein. Further analysis of the vat genomic locus identified a conserved gene located directly downstream of vat that encodes a putative MarR-like transcriptional regulator; we termed this gene vatX The vat-vatX genes were present in the UPEC reference strain CFT073, and reverse transcriptase PCR (RT-PCR) revealed that the two genes are cotranscribed. Overexpression of vatX in CFT073 led to a 3-fold increase in vat gene transcription. The vat promoter region contained three putative nucleation sites for the global transcriptional regulator histone-like nucleoid structuring protein (H-NS); thus, the hns gene was mutated in CFT073 (to generate CFT073 hns). Western blot analysis using a Vat-specific antibody revealed a significant increase in Vat expression in CFT073 hns compared to that in wild-type CFT073. Direct H-NS binding to the vat promoter region was demonstrated using purified H-NS in combination with electrophoresis mobility shift assays. Finally, Vat-specific antibodies were detected in plasma samples from urosepsis patients infected by vat-containing UPEC strains, demonstrating that Vat is expressed during infection. Overall, this study has demonstrated that Vat is a highly prevalent and tightly regulated immunogenic serine protease autotransporter protein of Enterobacteriaceae (SPATE) secreted by UPEC during infection. Uropathogenic Escherichia coli (UPEC) is the major cause of hospital- and community-acquired urinary tract infections. The vacuolating autotransporter toxin (Vat

  6. Using titer and titer normalized to confluence are complementary strategies for obtaining Chinese hamster ovary cell lines with high volumetric productivity of etanercept

    DEFF Research Database (Denmark)

    Pristovšek, Nuša; Hansen, Henning Gram; Sergeeva, Daria

    2018-01-01

    The selection of clonally-derived Chinese hamster ovary (CHO) cell lines with the highest production rate of recombinant glycoproteins remains a big challenge during early stages of cell line development. Different strategies using either product titer or product titer normalized to cell number...

  7. High-throughput immuno-profiling of mamba (Dendroaspis) venom toxin epitopes using high-density peptide microarrays

    DEFF Research Database (Denmark)

    Engmark, Mikael; Andersen, Mikael Rørdam; Laustsen, Andreas Hougaard

    2016-01-01

    Snakebite envenoming is a serious condition requiring medical attention and administration of antivenom. Current antivenoms are antibody preparations obtained from the plasma of animals immunised with whole venom(s) and contain antibodies against snake venom toxins, but also against other antigens....... In order to better understand the molecular interactions between antivenom antibodies and epitopes on snake venom toxins, a high-throughput immuno-profiling study on all manually curated toxins from Dendroaspis species and selected African Naja species was performed based on custom-made high...

  8. 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.

  9. High frequency of positive anti-thyroid peroxidase antibodies (ATPO) in adult subjects without known thyroid disease, Santiago de Chile

    International Nuclear Information System (INIS)

    Lanas, Alejandra; Letelier, Carolina; Caamano, Edgardo; Massardo, Teresa; Gonzalez, Patricio; Araya, Veronica

    2010-01-01

    Background: Anti-thyroid peroxidase antibodies have a pathogenic role in Hashimoto thyroiditis. Between 10 and 19% of individuals without thyroid disease, have positive titers of these antibodies. Aim: To study the frequency of positive titers of anti-thyroid peroxidase antibodies in healthy individuals. Material and Methods: A blood sample, to measure anti-thyroid peroxidase antibodies and thyroid stimulating hormone (TSH) by chemiluminescence assay, was obtained from 67 women and 62 men aged 45 ± 14 years, without a personal or familiar history of thyroid diseases and normal thyroid palpation. The cutoff point of the manufacturer to consider positive a titer of anti-thyroid peroxidase antibodies was set at 35 IU/ml. Results: Twenty-eight women and 28 men had positive antibody titers (43% of the sample). Subjects in the upper tercile of anti-thyroid peroxidase antibody titers had a higher TSH than those in the second tercile, although within normal limits (1.73 ± 0.74 and 1.37 ± 0.59 mlU/L, respectively p = 0.02) Conclusions: Forty three percent of the studied subjects without personal or familial history of thyroid diseases had positive titers of anti-thyroid peroxidase antibodies. Further prospective studies should evaluate whether this observation discloses an increase in thyroid autoimmune disease in a population with increased iodine intake

  10. Respons Antibodi Sekunder Terhadap Penyakit Tetelo pada Ayam Petelur Pascavaksinasi Ulangan dengan Vaksin Tetelo Aktif (NEWCASTLE DISEASESECONDARY ANTIBODY RESPONSE AFTER REVACCINATION IN LAYER WITH THE ACTIVE ND VACCINE

    Directory of Open Access Journals (Sweden)

    Andika Budi Kurnianto

    2016-11-01

    Full Text Available Revaccination is required in order to preventNewcastle Disease (ND reccurence inlayers chickens. Oneof vaccine for ND revaccination is freeze-died ND active vaccine containing e” 106,5EID50. Revaccinationisdone to trigger a faster secondary antibody responses in layers and can achieve protective antibody titersagainst ND that can be monitored by a hemagglutinationinhibition (HI. The aim of this study was todetermine the ND secondary antibody responses in layers after revaccination with ND active vaccine.Antibody titer of 20 layers chickens of 20 week old were determined before revaccinations (week 0 andafter revaccinations (week 1 until week 9. The first vaccination was conducted using ND-IB (NewcastleDisease-Infectious Bronchitis at the age of 2 days through eye drops and subcutaneous injection at the ageof 5 days using a dose of 1 ampoule.Vaccination is repeated at the age of 20 weeks at a dose of 1 ½ ampoule through drinking water. Blood samples were collected on the wing vein (venous cutane ulnar and left for 5-10 minutes at room temperature.Sera were then collected and stored at -20oC until use. HI antibody titerwas determined by micro titeration system. The HI mean titers were analyzed by Duncan test. The studyresults showed that antibody titer before revaccination was3,47 HI log 2 and the HI titers after revaccinationwere 4,02; 5,22; 6,52; 7,85; 8,4; 8,6; 7,7; 5,92; dan 3,87 HI log 2 respectivelly at weeks 1, 2, 3, 4, 5, 6, 7, 8, and9.The NDV revaccination with ND active vaccine significantly (P <0.01 increased in antibody titer inlayers starting from week 1 to week 6, but decreased following week 7 to week-9. It can be concluded thatrevaccinantion with ND active vaccine increases the antibody titers in layer chickens.

  11. Distribution of anti-Toxoplasma gondii antibodies among Orang Asli (aborigines) in Peninsular Malaysia.

    Science.gov (United States)

    Hakim, S L; Radzan, T; Nazma, M

    1994-09-01

    The distribution of anti-toxoplasma antibodies among the aborigines in Malaysia and its association with other soil transmitted infections and eosinophilia were studied. A total of 415 serum samples were collected and tested by IFA test. Overall prevalence was 10.6%, lower than previously reported. The antibody titers showed a unimodal distribution peaking at 1:8 dilution. There was a higher proportion of high antibody titer (> 1:128) in the adult compared to the children with no significant difference in prevalence rate by sex. The pattern of infection does not differ from other soil transmitted infections and there was no association between raised Toxoplasma antibodies with eosinophilia.

  12. Serum Titers of Acute Phase Proteins and Immunoglobulin Classes ...

    African Journals Online (AJOL)

    There were no significant correlation between duration of smoking, nicotine inhaled, and tar inhaled with any of the humoral factors. Conclusion: This study detected abnormalities in certain aspects of humoral immune responses in Nigerian smokers and this could lead to development of auto-antibodies and cardiovascular ...

  13. Monoclonal antibodies for treating cancer

    International Nuclear Information System (INIS)

    Dillman, R.O.

    1989-01-01

    The purpose of this study is to assess the current status of in-vivo use of monoclonal antibodies for treating cancer. Publications appearing between 1980 and 1988 were identified by computer searches using MEDLINE and CANCERLIT, by reviewing the table of contents of recently published journals, and by searching bibliographies of identified books and articles. More than 700 articles, including peer-reviewed articles and book chapters, were identified and selected for analysis. The literature was reviewed and 235 articles were selected as relevant and representative of the current issues and future applications for in-vivo monoclonal antibodies for cancer therapy and of the toxicity and efficacy which has been associated with clinical trials. Approaches include using antibody alone (interacting with complement or effector cells or binding directly with certain cell receptors) and immunoconjugates (antibody coupled to radioisotopes, drugs, toxins, or other biologicals). Most experience has been with murine antibodies. Trials of antibody alone and radiolabeled antibodies have confirmed the feasibility of this approach and the in-vivo trafficking of antibodies to tumor cells. However, tumor cell heterogeneity, lack of cytotoxicity, and the development of human antimouse antibodies have limited clinical efficacy. Although the immunoconjugates are very promising, heterogeneity and the antimouse immune response have hampered this approach as has the additional challenge of chemically or genetically coupling antibody to cytotoxic agents. As a therapeutic modality, monoclonal antibodies are still promising but their general use will be delayed for several years. New approaches using human antibodies and reducing the human antiglobulin response should facilitate treatment. 235 references

  14. Intracellular Targeting of CEA Results in Th1-Type Antibody Responses Following Intradermal Genetic Vaccination by a Needle-Free Jet Injection Device

    Directory of Open Access Journals (Sweden)

    Susanne Johansson

    2007-01-01

    Full Text Available The route and method of immunization, as well as the cellular localization of the antigen, can influence the generation of an immune response. In general, intramuscular immunization results in Th1 responses, whereas intradermal delivery of DNA by gene gun immunization often results in more Th2 responses. Here we investigate how altering the cellular localization of the tumor antigen CEA (carcinoembryonic antigen affects the quality and amplitude of DNA vaccine-induced antibody responses in mice following intradermal delivery of DNA by a needle-free jet injection device (Biojector. CEA was expressed either in a membrane-bound form (wild-type CEA or in two truncated forms (CEA6 and CEA66 with cytoplasmic localization, where CEA66 was fused to a promiscuous T-helper epitope from tetanus toxin. Repeated intradermal immunization of BALB/c mice with DNA encoding wild-type CEA produced high antibody titers of a mixed IgG1/IgG2a ratio. In contrast, utilizing the DNA construct that resulted in intracellular targeting of CEA led to a reduced capacity to induce CEA-specific antibodies, but instead induced a Th1-biased immune response.

  15. Rubella antibodies in Australian immunoglobulin products.

    Science.gov (United States)

    Young, Megan K; Bertolini, Joseph; Kotharu, Pushpa; Maher, Darryl; Cripps, Allan W

    2017-08-03

    Rubella antibodies are not routinely measured in immunoglobulin products and there is a lack of information on the titer in Australian products. To facilitate future studies of the effectiveness of passive immunisation for preventing rubella and congenital rubella syndrome, this study measured the concentration of rubella-specific antibodies in Australian intramuscular (IM) and intravenous (IV) human immunoglobulin products suitable for post-exposure prophylaxis using a chemiluminescent immunoassay. The GMT ± GSD for the IM product was 19 ± 1.2 IU/mg (2980 ± 1.2 IU/mL). The GMT ± GSD for the IV product was 12 ± 1.5 IU/mg (729 ± 1.5 IU/mL). At present, Australian guidelines recommend offering non-immune pregnant women exposed to rubella 20 mL of intramuscular immunoglobulin within 72 hours of exposure. This equates to 42,160 IU of rubella antibodies if the lowest titer obtained for the Australian IM product is considered. The same dose would be delivered by 176 mL of the Australian IV product at the lowest measured rubella-specific antibody titer.

  16. RESISTANCE OF GUINEA PIGS IMMUNIZED WITH BOTULINUM TOXOIDS TO AEROGENIC CHALLENGE WITH TOXIN

    Science.gov (United States)

    guinea pigs with botulinum toxoids afforded a high level of protection to challenge with botulinum toxins by the respiratory route. Resistance to challenge by this route was similar to resistance afforded to challenge by the parenteral and oral routes. The high survival percentages obtained in these studies made it impossible to establish any relationship between serum antitoxin titer and resistance to challenge. This report presents results of some studies to determine resistance afforded actively immunized guinea pigs to challenge with botulinum

  17. Antiradiation Vaccine: Immunological neutralization of Radiation Toxins at Acute Radiation Syndromes.

    Science.gov (United States)

    Popov, Dmitri; Maliev, Slava

    Introduction: Current medical management of the Acute Radiation Syndromes (ARS) does not include immune prophylaxis based on the Antiradiation Vaccine. Existing principles for the treatment of acute radiation syndromes are based on the replacement and supportive therapy. Haemotopoietic cell transplantation is recomended as an important method of treatment of a Haemopoietic form of the ARS. Though in the different hospitals and institutions, 31 pa-tients with a haemopoietic form have previously undergone transplantation with stem cells, in all cases(100%) the transplantants were rejected. Lethality rate was 87%.(N.Daniak et al. 2005). A large amount of biological substances or antigens isolated from bacterias (flagellin and derivates), plants, different types of venom (honeybees, scorpions, snakes) have been studied. This biological active substances can produce a nonspecific stimulation of immune system of mammals and protect against of mild doses of irradiation. But their radioprotection efficacy against high doses of radiation were not sufficient. Relative radioprotection characteristics or adaptive properties of antioxidants were expressed only at mild doses of radiation. However antioxidants demonstrated a very low protective efficacy at high doses of radiation. Some ex-periments demonstrated even a harmful effect of antioxidants administered to animals that had severe forms of the ARS. Only Specific Radiation Toxins roused a specific antigenic stim-ulation of antibody synthesis. An active immunization by non-toxic doses of radiation toxins includes a complex of radiation toxins that we call the Specific Radiation Determinant (SRD). Immunization must be provided not less than 24 days before irradiation and it is effective up to three years and more. Active immunization by radiation toxins significantly reduces the mortality rate (100%) and improves survival rate up to 60% compare with the 0% sur-vival rate among the irradiated animals in control groups

  18. Radioimmunoassay for Zearalenone and Zearalanol in Human Serum: Production, Properties, and Use of Porcine Antibodies

    OpenAIRE

    Thouvenot, Daniel; Morfin, Robert F.

    1983-01-01

    To produce antigens susceptible to raise antibodies for resorcylic acid lactones, the 6′-carboxymethyloxime derivatives of zearalenone and zearalanone were bound to bovine serum albumin. Pigs could be immunized by using these antigens, the best titer in antibodies being obtained with the zearalenone antigen. The porcine antibodies were specific for the resorcylic acid lactones of structural resemblance with zearalenone. This specificity made the antibodies usable for a radioimmunoassay of zea...

  19. Long term impact of high titer Edmonston-Zagreb measles vaccine on T lymphocyte subsets

    DEFF Research Database (Denmark)

    Lisse, I M; Aaby, P; Knudsen, K

    1994-01-01

    Several trials of high titer measles vaccine (> 10(4.7) plaque-forming unit) have found female recipients of Edmonston-Zagreb (EZ) vaccine to have lower survival than female recipients of standard measles vaccine. Two trials with medium and high titer EZ vaccine from the age of 4 months were...... unlikely to explain the reduced survival which has been associated with high titer EZ measles vaccination. In the 2 years after the investigation of T cell subsets, there was no increased mortality for recipients of EZ vaccine. Hence it is unlikely that high titer vaccine has an persistent adverse effect...

  20. Botulinum Toxin for Rhinitis.

    Science.gov (United States)

    Ozcan, Cengiz; Ismi, Onur

    2016-08-01

    Rhinitis is a common clinical entity. Besides nasal obstruction, itching, and sneezing, one of the most important symptoms of rhinitis is nasal hypersecretion produced by nasal glands and exudate from the nasal vascular bed. Allergic rhinitis is an IgE-mediated inflammatory reaction of nasal mucosa after exposure to environmental allergens. Idiopathic rhinitis describes rhinitis symptoms that occur after non-allergic, noninfectious irritants. Specific allergen avoidance, topical nasal decongestants, nasal corticosteroids, immunotherapy, and sinonasal surgery are the main treatment options. Because the current treatment modalities are not enough for reducing rhinorrhea in some patients, novel treatment options are required to solve this problem. Botulinum toxin is an exotoxin generated by Clostridium botulinum. It disturbs the signal transmission at the neuromuscular and neuroglandular junction by inhibiting the acetylcholine release from the presynaptic nerve terminal. It has been widely used in neuromuscular, hypersecretory, and autonomic nerve system disorders. There have been a lot of published articles concerning the effect of this toxin on rhinitis symptoms. Based on the results of these reports, intranasal botulinum toxin A administration appears to be a safe and effective treatment method for decreasing rhinitis symptoms in rhinitis patients with a long-lasting effect. Botulinum toxin type A will be a good treatment option for the chronic rhinitis patients who are resistant to other treatment methods.

  1. Effectiveness of the high dose/refuge strategy for managing pest resistance to Bacillus thuringiensis (Bt) plants expressing one or two toxins.

    Science.gov (United States)

    Gryspeirt, Aiko; Grégoire, Jean-Claude

    2012-10-01

    To delay resistance development to Bacillus thuringiensis (Bt) plants expressing their own insecticide, the application of the Insect Resistance Management strategy called "High Dose/Refuge Strategy" (HD/R) is recommended by the US Environmental Protection Agency (US EPA). This strategy was developed for Bt plants expressing one toxin. Presently, however, new Bt plants that simultaneously express two toxins are on the market. We used a mathematical model to evaluate the efficiency of the HD/R strategy for both these Bt toxins. As the current two-toxin Bt plants do not express two new Cry toxins but reuse one toxin already in use with a one-toxin plant, we estimated the spread of resistance when the resistance alleles are not rare. This study assesses: (i) whether the two toxins have to be present in high concentration, and (ii) the impact of the relative size of the refuge zone on the evolution of resistance and population density. We concluded that for Bt plants expressing one toxin, a high concentration is an essential condition for resistance management. For the pyramided Bt plants, one toxin could be expressed at a low titer if the two toxins are used for the first time, and a small refuge zone is acceptable.

  2. Absence of hemolytic disease of fetus and newborn despite maternal high-titer IgG anti-Ku.

    Science.gov (United States)

    Kakaiya, R M; Whaley, A; Howard-Menk, C; Rami, J; Papari, M; Campbell-Lee, S; Malecki, Z

    2010-01-01

    Anti-Ku seen in K(o) (Kell-null) individuals has previously been shown to cause severe hemolytic transfusion reactions. Maternal anti-Ku can cause none or moderate to severe hemolytic disease of the fetus and newborn (HDFN). In two of four previously described HDFN cases, intrauterine transfusions were required because of severe anemia. We report a case in which maternal anti-Ku did not cause HDFN. Standard serologic methods were used for RBC antibody screening and identification, adsorption and elution of RBC antibodies, and antigen typing. A gravida 3, para 3 (G3P3) woman was first evaluated in 2006 and was found to have an IgG RBC antibody that reacted against all panel RBCs in the anti-human globulin phase. A panel of RBCs treated with DTT did not react with the antibody. The antibody failed to react with one example of K(o) RBCs. The patient’s RBCs typed negative for the following Kell blood group antigens: KEL1, KEL2, KEL3, KEL4, KEL6, KEL7, KEL11, KEL13, and KEL18. These results established the presence of anti-Ku in maternal serum. The newborn was group A, D+ and required phototherapy for hyperbilirubinemia, but did not require transfusion. The woman was seen again in January 2010 during the third trimester (G4P3). At this time, anti-Ku titer was 256. She delivered a healthy group O, D+ baby boy at 37 weeks' gestation. Cord RBCs were 4+ for IgG by DAT. An eluate reacted with all RBCs tested, but did not react when tested against a panel of DTT-treated RBCs. K(o) phenotype is rare to begin with, and the maternal anti-Ku formation may require more than one pregnancy. Therefore, cases that can be evaluated for anti-Ku–related HDFN are rare. Our case contributes to serologic and clinical aspects of such rare cases.

  3. Functionally fused antibodies--a novel adjuvant fusion system

    DEFF Research Database (Denmark)

    Larsen, Martin; Jensen, Kim Bak; Christensen, Peter Astrup

    2008-01-01

    Antibodies capable of recognizing key molecular targets isolated e.g. by phage display technology have been used in the pursuit of new and improved therapies for prevalent human diseases. These approaches often take advantage of non-immunogenic antibody fragments to achieve specific toxin-, radio...

  4. Carbohydrate inhibitors of cholera toxin.

    Science.gov (United States)

    Kumar, Vajinder; Turnbull, W Bruce

    2018-01-01

    Cholera is a diarrheal disease caused by a protein toxin released by Vibrio cholera in the host's intestine. The toxin enters intestinal epithelial cells after binding to specific carbohydrates on the cell surface. Over recent years, considerable effort has been invested in developing inhibitors of toxin adhesion that mimic the carbohydrate ligand, with particular emphasis on exploiting the multivalency of the toxin to enhance activity. In this review we introduce the structural features of the toxin that have guided the design of diverse inhibitors and summarise recent developments in the field.

  5. Cholera toxin B subunit-binding and ganglioside GM1 immuno-expression are not necessarily correlated in human salivary glands

    DEFF Research Database (Denmark)

    Kirkeby, Svend

    2014-01-01

    OBJECTIVE: To determine and compare the presence and in situ localization of the glycosphingolipid ganglioside GM1 in human salivary glands using the biomarkers for GM1: cholera toxin and antibodies against GM1. MATERIALS AND METHODS: Immunohistochemical analyses were performed on sections of adult...... human submandibular, parotid and palatinal glands using cholera toxin sub-unit B and two polyclonal antibodies against ganglioside GM1 as biomarkers. RESULTS: Immunofluorescence microscopy showed that the toxin and antibodies were co-localized in some acini but not in others. The cholera toxin mainly...... reacted with the cell membranes of the mucous acini in the submandibular gland, while incubation with the antibody against GM1 gave rise to a staining of the cytoplasm. The cytoplasm in some secretory acinar cells in the parotid gland was stained by the cholera toxin, whereas only small spots...

  6. Anti-heat shock protein 27 titers and oxidative stress levels are elevated in patients with valvular heart disease.

    Science.gov (United States)

    Rahsepar, Amir Ali; Mirzaee, Asadollah; Moodi, Fatemeh; Moohebati, Mohsen; Tavallaie, Shima; Eshraghi, Ali; Alavi, Maryam-Sadat; Zarrabi, Laya; Pourghadamyari, Hossein; Paydar, Roghayeh; Khojasteh, Roshanak; Mousavi, Somayeh; Kia, Nadia; Amini, Maral; Ghayour-Mobarhan, Majid; Ferns, Gordon A A

    2012-11-01

    We studied the immune responses to heat shock protein (Hsp)-27 and pro-oxidant-antioxidant balance (PAB) values in patients with valvular heart disease, but free of angiographically evident coronary artery disease (CAD). Patients who were candidates for valvuloplasty surgery and 30 healthy matched controls were recruited. The anti-Hsp-27 antibody titers were 0.35 ± 0.04 absorbency units (AU) in the valvuloplasty group, being significantly higher than for the controls (0.11 ± 0.02 AU; P .05). Based on the echocardiographic findings, the patients had no evident heart failure, but the high levels of anti-Hsp-27 and PAB values in patients with valvular heart disease may indicate that these variables can be used as markers of heart failure. However, a longitudinal study is required to confirm this hypothesis.

  7. Autoproteolytic Activation of Bacterial Toxins

    Directory of Open Access Journals (Sweden)

    Aimee Shen

    2010-05-01

    Full Text Available Protease domains within toxins typically act as the primary effector domain within target cells. By contrast, the primary function of the cysteine protease domain (CPD in Multifunctional Autoprocessing RTX-like (MARTX and Clostridium sp. glucosylating toxin families is to proteolytically cleave the toxin and release its cognate effector domains. The CPD becomes activated upon binding to the eukaryotic-specific small molecule, inositol hexakisphosphate (InsP6, which is found abundantly in the eukaryotic cytosol. This property allows the CPD to spatially and temporally regulate toxin activation, making it a prime candidate for developing anti-toxin therapeutics. In this review, we summarize recent findings related to defining the regulation of toxin function by the CPD and the development of inhibitors to prevent CPD-mediated activation of bacterial toxins.

  8. Pertussis Antibody Transfer to Preterm Neonates After Second- Versus Third-Trimester Maternal Immunization.

    Science.gov (United States)

    Eberhardt, Christiane S; Blanchard-Rohner, Geraldine; Lemaître, Barbara; Combescure, Christophe; Othenin-Girard, Véronique; Chilin, Antonina; Petre, Jean; Martinez de Tejada, Begoña; Siegrist, Claire-Anne

    2017-04-15

    Preterm infants are most vulnerable to pertussis. Whether they might benefit from maternal immunization is unknown. Extending our previous results in term neonates, this observational study demonstrates that second- rather than third-trimester maternal vaccination results in higher birth anti-pertussis toxin titers in preterm neonates. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

  9. Pertussis Antibody Transfer to Preterm Neonates After Second- Versus Third-Trimester Maternal Immunization

    OpenAIRE

    Eberhardt, Christiane S.; Blanchard-Rohner, Geraldine; Lema?tre, Barbara; Combescure, Christophe; Othenin-Girard, V?ronique; Chilin, Antonina; Petre, Jean; Martinez de Tejada, Bego?a; Siegrist, Claire-Anne

    2017-01-01

    Abstract Preterm infants are most vulnerable to pertussis. Whether they might benefit from maternal immunization is unknown. Extending our previous results in term neonates, this observational study demonstrates that second- rather than third-trimester maternal vaccination results in higher birth anti?pertussis toxin titers in preterm neonates.

  10. Antistreptolysin O titer in health and disease: levels and significance

    Directory of Open Access Journals (Sweden)

    Alyaa Amal Kotby

    2012-02-01

    Full Text Available Over diagnosis of acute rheumatic fever (ARF based on a raised antistreptolysin O titer (ASOT is not uncommon in endemic areas. In this study, 660 children (aged 9.2 ±1.7 years were recruited consecutively and classified as: G1 (control group, n=200 healthy children, G2 (n=20 with ARF 1st attack, G3 (n=40 with recurrent ARF, G4 (n=100 with rheumatic heart disease (RHD on long acting penicillin (LAP, G5 (n=100 with acute follicular tonsillitis, and G6 (n=200 healthy children with history of repeated follicular tonsillitis more than three times a year. Serum ASOT was measured by latex agglutination. Upper limit of normal (ULN ASOT (80th percentile was 400 IU in G1, 200 IU in G4, and 1600 IU in G6. Significantly high levels were seen in ARF 1st attack when compared to groups 1 and 5 (P<0.001 and P<0.05, respectively. ASOT was significantly high in children over ten years of age, during winter and in those with acute rheumatic carditis. ASOT showed significant direct correlation with the number of attacks of tonsillitis (P<0.05. Egyptian children have high ULN ASOT reaching 400 IU. This has to be taken into consideration when interpreting its values in suspected ARF. A rise in ASOT is less prominent in recurrent ARF compared to 1st attack, and acute and recurrent tonsillitis. Basal levels of ASOT increase with age but the pattern of increase during infection is not age dependent

  11. 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 ...

  12. Durability of immunity by hepatitis B vaccine in Japanese health care workers depends on primary response titers and durations.

    Directory of Open Access Journals (Sweden)

    Nori Yoshioka

    Full Text Available Health care workers (HCWs are frequently exposed to hepatitis B virus (HBV infection. The efficacy and safety of immunization with the hepatitis B (HB vaccine are well recognized, but the durability of immunity and need for booster doses in those with secondary vaccine response failure remains controversial.This was a retrospective cohort study performed at Osaka University Hospital, Japan. We examined antibodies against HB surface antigen (anti-HBs titers annually after immunization for previously non-immunized HCWs. Primary responders were categorized by their sero-positive durations as short responders (those whose anti-HBs titers declined to negative range within 3 years, and long responders (those who retained positive anti-HBs levels for 3 years and more. We re-immunized short responders with either single or 3-dose boosters, the long responders with a single booster when their titers dropped below protective levels, and examined their sero-protection rates over time thereafter.From 2001 to 2012, data of 264 HCWs with a median age of 25.3 were collected. The rate of anti-HBs positivity after primary vaccination were 93.0% after three doses (n = 229, 54.5% after two doses (n = 11, and 4.2% after a single dose (n = 24. Of 213 primary responders, the anti-HBs levels of 95 participants (44.6% fell below the protective levels, including 46 short responders and 49 long responders. HCWs with higher initial anti-HBs titers after primary vaccination had significantly longer durations of sero-positivity. For short responders, 3-dose booster vaccination induced a longer duration of anti-HBs positivity compared to a single-dose booster, whereas for long responders, a single-dose booster alone could induce prolonged anti-HBs positivity.Our preliminary data suggested that it may be useful to differentiate HB vaccine responders based on their primary response durations to maintain protective levels of anti-HBs efficiently. A randomized, prospective

  13. Monoclonal antibodies directed to E1 glycoprotein of rubella virus

    International Nuclear Information System (INIS)

    Umino, Y.; Sato, A.; Katow, S.; Matsuno, T.; Sugiura, A.

    1985-01-01

    We have prepared four monoclonal antibodies to rubella virus E1 glycoprotein. Three nonoverlapping antigenic sites were delineated on E1 protein by competitive binding assays. Antibodies binding to one site were characterized by high hemagglutination inhibition (HI) titer but poor neutralizing activity. The addition of antiglobulin conferred neutralizing activity. Antibodies directed to two other antigenic sites had modest hemolysis inhibition but little or no HI and neutralizing activities. The addition of antiglobulin markedly augmented HI activity but had little effect on neutralizing activity. Epitopes defined by three antibodies were conserved among four rubella virus strains examined. (Author)

  14. Low titer lentiviral transgenesis in rodents with simian immundeficiency virus vector.

    Science.gov (United States)

    Bender, Balázs; Hoffmann, Orsolya Ivett; Negre, Didier; Kvell, Krisztián; Bősze, Zsuzsanna; Hiripi, László

    2013-09-01

    Efficient production of transgenic animals using low-titer lentiviral constructs remains challenging. Here we demonstrate that microinjection of simian immundeficiency virus-derived lentiviral constructs can produce transgenic mice and rats with high efficiency even when using low-titer virus preparations.

  15. Occurrence of anti-Neospora caninum and anti-Toxoplasma gondii antibodies in horses in the Pantanal of Mato Grosso, Brazil

    Directory of Open Access Journals (Sweden)

    Luciane Maria Laskoski

    2015-04-01

    Full Text Available This study aimed to evaluate the occurrence of anti-Neospora caninum and anti-Toxoplasma gondii antibodies in horses from Pantanal, in Mato Grosso state. Two hundred blood samples were collected from horses in Pantanal of Mato Grosso, Brazil. The samples were analyzed by IFAT for the detection of anti-Neospora caninum and anti-Toxoplasma gondii antibodies. Antibodies to N. caninum were found in 30 (15% of 200 horses in titers of 50 (25 horses, 100 (two horses, 200 (two horses, and 400 (one horse. Antibodies to T. gondii were found in five (2.5% of 200 horses in titers of 50 (three horses, 200 (one horse, and 400 (one horse. One animal showed antibody titers for both coccidian (titers of 200 for N. caninum e 400 for T. gondii. The pantaneiros horses were exposed to Neospora spp. and T. gondii.

  16. Long term impact of high titer Edmonston-Zagreb measles vaccine on T lymphocyte subsets

    DEFF Research Database (Denmark)

    Lisse, I M; Aaby, P; Knudsen, K

    1994-01-01

    conducted in Guinea-Bissau. To test for possible long term impact on the immune system, an investigation of T cell subsets was conducted among all children still residing in the community at 3 to 5 years of age. No differences were found between recipients of medium titer vaccine and controls. In the second......Several trials of high titer measles vaccine (> 10(4.7) plaque-forming unit) have found female recipients of Edmonston-Zagreb (EZ) vaccine to have lower survival than female recipients of standard measles vaccine. Two trials with medium and high titer EZ vaccine from the age of 4 months were...... unlikely to explain the reduced survival which has been associated with high titer EZ measles vaccination. In the 2 years after the investigation of T cell subsets, there was no increased mortality for recipients of EZ vaccine. Hence it is unlikely that high titer vaccine has an persistent adverse effect...

  17. A stable reagent system for screening and identifying red blood cell irregular antibodies: application to commercial antibodies.

    Science.gov (United States)

    Million, L; Pellerin, C; Marchand-Arvier, M; Vigneron, C

    1998-01-01

    Development of a new solid-phase system for screening and identifying irregular red cell antibodies. Red blood cell membranes were prepared by a semi-automated procedure in which the hemolysate solution was passed through a hollow-fiber system. The membranes were fixed to the solid phase (microtiter plates) by centrifugation and incubated with 8% fat-free milk. Antibodies added to the microtiter plate were detected by anti-human antibodies adsorbed onto yellow latex particles. The system had good sensitivity (titer antibodies that are important in transfusion.

  18. Improved quantification of a commercial enzyme-linked immunosorbent assay kit for measuring anti-MDA5 antibody.

    Science.gov (United States)

    Gono, Takahisa; Okazaki, Yuka; Murakami, Akihiro; Kuwana, Masataka

    2018-04-09

    To compare the quantitative performance for measuring anti-MDA5 antibody titer of two enzyme-linked immunosorbent assay (ELISA) systems: an in-house ELISA and the commercial MESACUP TM anti-MDA5 test. Anti-MDA5 antibody titer was measured in sera from 70 patients with dermatomyositis using an in-house ELISA and the MESACUP TM anti-MDA5 test side-by-side. For the commercial ELISA kit, serum samples diluted 1:101 were used according to the manufacturer's protocol, but serial dilutions of sera were also examined to identify the optimal serum dilution for quantification. The anti-MDA5 antibody titers measured by the in-house and commercial ELISAs were positively correlated with each other (r = 0.53, p = .0001), but the antibody titer measured by the commercial ELISA was less sensitive to change after medical treatment, and 37 (80%) of 46 anti-MDA5-positive sera had antibody titer exceeding the quantification range specified by the manufacturer (≥150 index). Experiments using diluted serum samples revealed that diluting the sera 1:5050 improved the quantitative performance of the MESACUP TM anti-MDA5 test, including a better correlation with the in-house ELISA results and an increased sensitivity to change. We improved the ability of the commercial ELISA kit to quantify anti-MDA5 antibody titer by altering its protocol.

  19. Western blot can distinguish natural and acquired antibodies to Mycoplasma agassizii in the desert tortoise (Gopherus agassizii).

    Science.gov (United States)

    Hunter, Kenneth W; Dupré, Sally A; Sharp, Tiffanny; Sandmeier, Franziska C; Tracy, C Richard

    2008-12-01

    Mycoplasma agassizi has been identified as a cause of upper respiratory tract disease (URTD) in the threatened Mojave population of the desert tortoise (Gopherus agassizii), and anti-M. agassizii antibodies have been found by ELISA in as many as 15% of these animals across their geographic range. Here we report that a cohort of 16 egg-reared desert tortoises never exposed to M. agassizii had ELISA antibody titers to this organism that overlapped with titers obtained from some M. agassizii-infected tortoises. These natural antibodies were predominantly of the IgM class. Western blots of plasma from these non-infected tortoises produced a characteristic banding pattern against M. agassizii antigens. A group of 38 wild-caught desert tortoises was tested by ELISA, and although some of these tortoises had antibody titers significantly higher than the non-infected tortoises, there was considerable overlap at the lower titer levels. However, Western blot analysis revealed distinct banding patterns that could readily distinguish between the non-infected tortoises and tortoises with acquired antibodies, regardless of ELISA antibody titers. We conclude that desert tortoises have natural antibodies to M. agassizii that can compromise the determination of infection status by ELISA. However, the Western blot technique can distinguish between natural and acquired antibody patterns and can be used to confirm the diagnosis of M. agassizii infections in the desert tortoise.

  20. Role of antibodies in protection elicited by active vaccination with genetically inactivated alpha hemolysin in a mouse model of staphylococcus aureus skin and soft tissue infections.

    Science.gov (United States)

    Mocca, Christopher P; Brady, Rebecca A; Burns, Drusilla L

    2014-05-01

    Due to the emergence of highly virulent community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections, S. aureus has become a major threat to public health. A majority of CA-MRSA skin and soft tissue infections in the United States are caused by S. aureus USA300 strains that are known to produce high levels of alpha hemolysin (Hla). Therefore, vaccines that contain inactivated forms of this toxin are currently being developed. In this study, we sought to determine the immune mechanisms of protection for this antigen using a vaccine composed of a genetically inactivated form of Hla (HlaH35L). Using a murine model of skin and soft tissue infections (SSTI), we found that BALB/c mice were protected by vaccination with HlaH35L; however, Jh mice, which are deficient in mature B lymphocytes and lack IgM and IgG in their serum, were not protected. Passive immunization with anti-HlaH35L antibodies conferred protection against bacterial colonization. Moreover, we found a positive correlation between the total antibody concentration induced by active vaccination and reduced bacterial levels. Animals that developed detectable neutralizing antibody titers after active vaccination were significantly protected from infection. These data demonstrate that antibodies to Hla represent the major mechanism of protection afforded by active vaccination with inactivated Hla in this murine model of SSTI, and in this disease model, antibody levels correlate with protection. These results provide important information for the future development and evaluation of S. aureus vaccines.

  1. Anticarbohydrate Antibody Repertoires in Patients Transplanted with Fetal Pig Islets Revealed by Glycan Arrays

    DEFF Research Database (Denmark)

    Blixt, Klas Ola; Kumagai-Braesch, A.; Tibell, A.

    2009-01-01

    Ten patients with type I diabetes were transplanted with porcine fetal islet-like cell clusters (ICC) between 1990 and 1993. A significant rise in the anti-a-Gal antibody titers was seen posttransplant, but also non-a-Gal-specific antibodies were detected in some patients. We have reanalyzed...

  2. Erosive arthritis and anti-cyclic citrullinated peptide antibodies in systemic sclerosis

    Directory of Open Access Journals (Sweden)

    A Abdessemed

    2017-01-01

    Conclusion: Erosive arthritis is not rare in SSc, and it might be a marker of severe disease. Anti-CCP antibodies can be present in patients with SSc, and high titers of anti-CCP antibodies may be indicative of SSc-RA overlap syndrome.

  3. Newcastle disease virus and antibody levels in matched sera ...

    African Journals Online (AJOL)

    Haemagglutination inhibition assay was performed for all sera and egg yolk samples. Protective serum antibody titres of ≥3 (log2) were recorded in 5.3% of the naturally exposed, indigenous village hens. Antibody titers to Newcastle disease virus in the yolks were higher than in their sera (230.08 ± 40.05; 1.56 ± 0.74 for ...

  4. [Detection and analysis of anti-Rh blood group antibodies].

    Science.gov (United States)

    Wu, Yuan-jun; Wu, Yong; Chen, Bao-chan; Liu, Yan

    2008-06-01

    To study the prevalence and distribution of anti-Rh blood group antibodies in Chinese population and its clinical significance. Irregular antibodies were screened and identified by Microcolum Gel Coomb's test. For those identified as positive anti-Rh samples, monoclonal antibodies (anti-D, -C, -c, -E and -e) were used to identify the specific antigen and confirm the accuracy of the irregular antibody tests. The titers, Ig-types and 37 Degrees Celsius-reactivity were tested to confirm its clinical significance. For evaluation of the origin of irregular antibodies, histories of pregnancy and transfusion were reviewed. For the newborns who had positive antibodies, their mothers were tested simultaneously to confirm the origin of the antibodies. 47 out of 54 000 (0.087%) patients were identified as positive with Rh blood group antibodies.Of them, 27 cases had history of pregnancy, 13 had transfusion and 1 had the histories of both. 6 newborns had antibodies derived form their mothers. The specificity of the antibody was as follows: 29 with anti-E (61.70%), 8 with anti-D (17.02%), anti-cE 5(10.64%), 4 with anti-c (8.51%) and 1 with anti-C (2.13%). All the 47 Rh blood group antibodies were IgG or IgG+IgM, and were reactive to red blood cells with corresponding antigens at 37 Degrees Celsius, with a highest titer of 1:4 096. The prevalence of Rh antibodies is lower in Chinese population as compared with that in White population.Of all the antibodies, anti-E is most frequently identified and anti-D was declining. Alloimmunization by pregnancy and transfusion is the major cause of Rh antibody production. Rh blood group antibodies derived from mothers are the major cause of Non-ABO-HDN.

  5. Arrangement of the Clostridium baratii F7 toxin gene cluster with identification of a σ factor that recognizes the botulinum toxin gene cluster promoters.

    Science.gov (United States)

    Dover, Nir; Barash, Jason R; Burke, Julianne N; Hill, Karen K; Detter, John C; Arnon, Stephen S

    2014-01-01

    Botulinum neurotoxin (BoNT) is the most poisonous substances known and its eight toxin types (A to H) are distinguished by the inability of polyclonal antibodies that neutralize one toxin type to neutralize any of the other seven toxin types. Infant botulism, an intestinal toxemia orphan disease, is the most common form of human botulism in the United States. It results from swallowed spores of Clostridium botulinum (or rarely, neurotoxigenic Clostridium butyricum or Clostridium baratii) that germinate and temporarily colonize the lumen of the large intestine, where, as vegetative cells, they produce botulinum toxin. Botulinum neurotoxin is encoded by the bont gene that is part of a toxin gene cluster that includes several accessory genes. We sequenced for the first time the complete botulinum neurotoxin gene cluster of nonproteolytic C. baratii type F7. Like the type E and the nonproteolytic type F6 botulinum toxin gene clusters, the C. baratii type F7 had an orfX toxin gene cluster that lacked the regulatory botR gene which is found in proteolytic C. botulinum strains and codes for an alternative σ factor. In the absence of botR, we identified a putative alternative regulatory gene located upstream of the C. baratii type F7 toxin gene cluster. This putative regulatory gene codes for a predicted σ factor that contains DNA-binding-domain homologues to the DNA-binding domains both of BotR and of other members of the TcdR-related group 5 of the σ70 family that are involved in the regulation of toxin gene expression in clostridia. We showed that this TcdR-related protein in association with RNA polymerase core enzyme specifically binds to the C. baratii type F7 botulinum toxin gene cluster promoters. This TcdR-related protein may therefore be involved in regulating the expression of the genes of the botulinum toxin gene cluster in neurotoxigenic C. baratii.

  6. Effect of increased CRM₁₉₇ carrier protein dose on meningococcal C bactericidal antibody response.

    Science.gov (United States)

    Lee, Lucia H; Blake, Milan S

    2012-04-01

    New multivalent CRM(197)-based conjugate vaccines are available for childhood immunization. Clinical studies were reviewed to assess meningococcal group C (MenC) antibody responses following MenC-CRM(197) coadministration with CRM(197)-based pneumococcal or Haemophilus influenzae type b conjugate vaccines. Infants receiving a total CRM(197) carrier protein dose of ∼50 μg and concomitant diphtheria-tetanus-acellular pertussis (DTaP)-containing vaccine tended to have lower MenC geometric mean antibody titers and continued to have low titers after the toddler dose. Nevertheless, at least 95% of children in the reported studies achieved a MenC serum bactericidal antibody (SBA) titer of ≥ 1:8 after the last infant or toddler dose. SBA was measured using an assay with a baby rabbit or human complement source. Additional studies are needed to assess long-term antibody persistence and MenC CRM(197) conjugate vaccine immunogenicity using alternative dosing schedules.

  7. A comparative study of the neutralisation test and the indirect fluorescent antibody technique for the detection of antibodies to the virus of Aujeszky in pig sera.

    Science.gov (United States)

    Wirahadiredja, R M; Rondhuis, P R

    1976-10-15

    A microneutralisation test and an indirect fluorescent antibody technique for the detection of antibodies to Aujeszky-virus in pig sera are described. All the sera were tested with both techniques and the results were compared. Serum dilutions of less than 1:32 which produced a positive reaction in the indirect FAT were considered nonspecific. Bij contrast, all neutralising antibody titers of less than 1:8 gave nonspecific reactions in the indirect FAT.

  8. New haptens and antibodies for ractopamine.

    Science.gov (United States)

    Wang, Zhanhui; Liu, Meixuan; Shi, Weimin; Li, Chenglong; Zhang, Suxia; Shen, Jianzhong

    2015-09-15

    In this work, three unreported immunizing haptens of ractopamine (RAC) were synthesized and used to produce highly sensitive and specific polyclonal antibody. The spacer arms of haptens for coupling to protein carrier were located on different position of RAC with different length. High affinity polyclonal antibodies were obtained and characterized in terms of titer and sensitivity by using enzyme-linked immunosorbent assay (ELISA). The best antibody employed in a heterologous competitive ELISA exhibited an IC50 value as low as 0.12ngmL(-1) and could not recognize other 10 β-agonists including clenbuterol and salbutamol. The heterologous competitive ELISA was preliminary applied to swine urine and the results showed the new antibody was sufficiently sensitive and specific, and potentially used for the detection of RAC at trace level in real samples. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Intranasal coadministration of Cholera toxin with amoeba lysates modulates the secretion of IgA and IgG antibodies, production of cytokines and expression of pIgR in the nasal cavity of mice in the model of Naegleria fowleri meningoencephalitis.

    Science.gov (United States)

    Carrasco-Yepez, Maricela; Campos-Rodriguez, Rafael; Lopez-Reyes, Israel; Bonilla-Lemus, Patricia; Rodriguez-Cortes, Antonio Yahve; Contis-Montes de Oca, Arturo; Jarillo-Luna, Adriana; Miliar-Garcia, Angel; Rojas-Hernandez, Saul

    2014-11-01

    The nasal mucosa is the first contact with antigens to induce IgA response. The role of this site has rarely been studied. We have shown than intranasal administration with Naegleria fowleri lysates plus Cholera toxin (CT) increased the protection (survival up to 100%) against N. fowleri infection in mice and apparently antibodies IgA and IgG together with polymorphonuclear (PMN) cells avoid the attachment of N. fowleri to apical side of the nasal epithelium. We also observed that nasal immunization resulted in the induction of antigen-specific IgG subclasses (IgG1 and IgG2a) in nasal washes at days 3 and 9 after the challenge and IgA and IgG in the nasal cavity, compared to healthy and infected mice. We found that immunization with both treatments, N. fowleri lysates plus CT or CT alone, increased the expression of the genes for alpha chain, its receptor (pIgR), and it also increased the expression of the corresponding proteins evidenced by the ∼65 and ∼74kDa bands, respectively. Since the production of pIgR, IgA and IgG antibodies, is up-regulated by some factors, we analyzed the expression of genes for IL-10, IL-6, IFN-γ, TNF-α and IL-1β by using RT-PCR of nasal passages. Immunization resulted in an increased expression of IL-10, IL-6, and IFN-γ cytokines. We also aimed to examine the possible influences of immunization and challenge on the production of inflammatory cytokines (TNF-α and IL-1β). We observed that the stimulus of immunization inhibits the production of TNF-α compared to the infected group where the infection without immunization causes an increase in it. Thus, it is possible that the coexistence of selected cytokines produced by our immunization model may provide a highly effective immunological environment for the production of IgA, IgG and pIgR as well as a strong activation of the PMN in mucosal effector tissue such as nasal passages. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. THE PASSAGE AND DURATION OF ANTIBODIES TO WEST NILE VIRUS IN HUMBOLDT PENGUINS (SPHENISCUS HUMBOLDTI).

    Science.gov (United States)

    Cushing, Andrew C; Dubovi, Edward; Erb, Hollis N; Georoff, Timothy A; Abou-Madi, Noha

    2017-03-01

    West Nile virus (genus Flavivirus) outbreaks and mortality events have been documented in both wild and captive avian species, including penguins. Serologic response to vaccination in avian species has varied and appears to be largely species dependent; however, Humboldt penguins ( Spheniscus humboldti ) previously showed excellent rates of seroconversion. The goal of this study was to determine virus neutralization titers of 17 Humboldt penguin hens and their subsequent eggs, chicks, or both following vaccination with a killed West Nile vaccine. Chicks were also vaccinated at 56, 70, and 84 days old. Titers were measured from 10-346 days prior to lay as well as serially in seven chicks. Data collected showed positive rank correlation between maternal titers and yolk titers (ρ = 0.90, P penguin chicks based on a time-dependent decline in maternal antibody titers. Cell-mediated immunity and experimental challenge following vaccination have not yet been investigated in this species.

  11. Antiprothrombin Antibodies

    Directory of Open Access Journals (Sweden)

    Polona Žigon

    2015-05-01

    Full Text Available In patients with the antiphospholipid syndrome (APS, the presence of a group of pathogenic autoantibodies called antiphospholipid antibodies causes thrombosis and pregnancy complications. The most frequent antigenic target of antiphospholipid antibodies are phospholipid bound β2-glycoprotein 1 (β2GPI and prothrombin. The international classification criteria for APS connect the occurrence of thrombosis and/or obstetric complications together with the persistence of lupus anticoagulant, anti-cardiolipin antibodies (aCL and antibodies against β2GPI (anti-β2GPI into APS. Current trends for the diagnostic evaluation of APS patients propose determination of multiple antiphospholipid antibodies, among them also anti-prothrombin antibodies, to gain a common score which estimates the risk for thrombosis in APS patients. Antiprothrombin antibodies are common in APS patients and are sometimes the only antiphospholipid antibodies being elevated. Methods for their determination differ and have not yet been standardized. Many novel studies confirmed method using phosphatidylserine/prothrombin (aPS/PT ELISA as an antigen on solid phase encompass higher diagnostic accuracy compared to method using prothrombin alone (aPT ELISA. Our research group developed an in-house aPS/PT ELISA with increased analytical sensitivity which enables the determination of all clinically relevant antiprothrombin antibodies. aPS/PT exhibited the highest percentage of lupus anticoagulant activity compared to aCL and anti-β2GPI. aPS/PT antibodies measured with the in-house method associated with venous thrombosis and presented the strongest independent risk factor for the presence of obstetric complications among all tested antiphospholipid antibodies

  12. Antibody response to equine coronavirus in horses inoculated with a bovine coronavirus vaccine.

    Science.gov (United States)

    Nemoto, Manabu; Kanno, Toru; Bannai, Hiroshi; Tsujimura, Koji; Yamanaka, Takashi; Kokado, Hiroshi

    2017-11-17

    A vaccine for equine coronavirus (ECoV) is so far unavailable. Bovine coronavirus (BCoV) is antigenically related to ECoV; it is therefore possible that BCoV vaccine will induce antibodies against ECoV in horses. This study investigated antibody response to ECoV in horses inoculated with BCoV vaccine. Virus neutralization tests showed that antibody titers against ECoV increased in all six horses tested at 14 days post inoculation, although the antibody titers were lower against ECoV than against BCoV. This study showed that BCoV vaccine provides horses with antibodies against ECoV to some extent. It is unclear whether antibodies provided by BCoV vaccine are effective against ECoV, and therefore ECoV challenge studies are needed to evaluate efficacy of the vaccine in the future.

  13. Magnetic Bead Based Immunoassay for Autonomous Detection of Toxins

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Y; Hara, C A; Knize, M G; Hwang, M H; Venkatesteswaran, K S; Wheeler, E K; Bell, P M; Renzi, R F; Fruetel, J A; Bailey, C G

    2008-05-01

    As a step towards toward the development of a rapid, reliable analyzer for bioagents in the environment, we are developing an automated system for the simultaneous detection of a group of select agents and toxins. To detect toxins, we modified and automated an antibody-based approach previously developed for manual medical diagnostics that uses fluorescent eTag{trademark} reporter molecules and is suitable for highly multiplexed assays. Detection is based on two antibodies binding simultaneously to a single antigen, one of which is labeled with biotin while the other is conjugated to a fluorescent eTag{trademark} through a cleavable linkage. Aqueous samples are incubated with the mixture of antibodies along with streptavidin-coated magnetic beads coupled to a photo-activatable porphyrin complex. In the presence of antigen, a molecular complex is formed where the cleavable linkage is held in proximity to the photoactivable group. Upon excitation at 680 nm, free radicals are generated, which diffuse and cleave the linkage, releasing the eTags{trademark}. Released eTags{trademark} are analyzed using capillary gel electrophoresis with laser-induced fluorescence detection. Limits of detection for ovalbumin and botulinum toxoid individually were 4 ng/mL (or 80 pg) and 16 ng/mL (or 320 pg), respectively, using the manual assay. In addition, we demonstrated the use of pairs of antibodies from different sources in a single assay to decrease the rate of false positives. Automation of the assay was demonstrated on a flow-through format with higher LODs of 125 ng/mL (or 2.5 ng) each of a mixture of ovalbumin and botulinum toxoid. This versatile assay can be easily modified with the appropriate antibodies to detect a wide range of toxins and other proteins.

  14. Inclusion Fluorescent-Antibody Test as a Screening Assay for Detection of Antibodies to Chlamydia pneumoniae

    OpenAIRE

    Tapia, Olga; Slepenkin, Anatoly; Sevrioukov, Evgueni; Hamor, Kathi; de la Maza, Luis M.; Peterson, Ellena M.

    2002-01-01

    A study was conducted to determine the ability of the inclusion immunofluorescence assay (inclusion IFA) to act as a screening test to detect samples with antibodies to Chlamydia pneumoniae; microimmunofluorescence (MIF) was used as the “gold standard.” In addition, the inclusion IFA was compared using HEp-2 cells infected with either C. pneumoniae CM-1 or Chlamydia trachomatis serovar E. A total of 331 serum samples representing a range of MIF titers were evaluated. The sensitivities of the ...

  15. [Screening analysis of irregular antibodies from random donor population in Shaoguan area].

    Science.gov (United States)

    Zhu, Jian-Ying; Lan, Jiong-Cai; Luo, Hong-Qing

    2007-06-01

    The study was purposed to analyze the frequency and distribution of irregular antibodies in Shaoguan area. Screening 15 033 random donor antibodies in Shaoguan area by screening cells, polybrene and antiglobulin tests. The results indicated that the irregular antibodies were found in 42 samples. The frequency of irregular antibodies in female was higher than that in male (P antibodies such as anti-D, anti-E, and anti-Ec C were common (47.6%). 2 samples of Le antibodies were failed to be found by polybrene test. 2 samples of irregular antibodies with titer 2 were undiscovered by screening test of 10 pooled samples. In conclusion, because of irregular antibodies resulting in hemolytic transfusion reaction, the investigation of frequency and distribution of irregular antibodies is very important for safe transfusion. Antibody screening must be done for female donors, and especially for massive plasma transfusion of patients with severe and dangerous illness and infants so as to ensure safety.

  16. Lymphocyte receptors for pertussis toxin

    Energy Technology Data Exchange (ETDEWEB)

    Clark, C.G.; Armstrong, G.D. (Univ. of Alberta, Edmonton (Canada))

    1990-12-01

    We have investigated human T-lymphocyte receptors for pertussis toxin by affinity isolation and photoaffinity labeling procedures. T lymphocytes were obtained from peripheral human blood, surface iodinated, and solubilized in Triton X-100. The iodinated mixture was then passed through pertussis toxin-agarose, and the fractions were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Autoradiography of the fixed, dried gels revealed several bands in the pertussis toxin-bound fraction that were not observed in fractions obtained from histone or fetuin-agarose. Further investigations employed a photoaffinity labeling reagent, sulfosuccinimidyl 2-(p-azido-salicylamido)-1,3'-dithiopropionate, to identify pertussis toxin receptors in freshly isolated peripheral blood monocytic cells, T lymphocytes, and Jurkat cells. In all three cell systems, the pertussis toxin affinity probe specifically labeled a single protein species with an apparent molecular weight of 70,000 that was not observed when the procedure was performed in the presence of excess unmodified pertussis toxin. A protein comparable in molecular weight to the one detected by the photoaffinity labeling technique was also observed among the species that bound to pertussis toxin-agarose. The results suggest that pertussis toxin may bind to a 70,000-Da receptor in human T lymphocytes.

  17. Chemo-enzymatic production of O-glycopeptides for the detection of serum glycopeptide antibodies

    DEFF Research Database (Denmark)

    Nøstdal, Alexander; Wandall, Hans H

    2013-01-01

    Protein microarray is a highly sensitive tool for antibody detection in serum. Monitoring of patients' antibody titers to specific antigens is increasingly employed in the diagnosis of several conditions, ranging from infectious diseases, allergies, autoimmune diseases, and cancer. In this protocol...... we present a detailed method for enzymatic generation of disease-specific O-glycopeptides and how to monitor the antibody response to these in serum using microarray technology....

  18. Passive transfer of Anti-Dirofilaria immitis hemagglutinating antibody from the mother dog to its offspring

    OpenAIRE

    Hayasaki, Mineo

    1982-01-01

    Twenty mother dogs, and their 19. fetuses and 57 newborn puppies were examined by the indirect hemagglutination (IHA) test for the transfer of anti-Dirofilaria immitis antibody from mothers to their offspring. The antibody was shown to be passively transferred via colostrum to the puppies and to persist in the puppies for approximately two months. On the other hand, no antibody was detected in the fetuses even when their mothers had high titers. The time-course studies indicated that, on the ...

  19. Correlation between ovarian growth, vitellogenin titer, and yolk polypeptide pattern in the haemolymph of Calliphora vicina

    DEFF Research Database (Denmark)

    Sørensen, Ilona Kryspin; Jensen, P. V.

    1982-01-01

    During the first egg maturation cycle ofCalliphora vicina changes in the vitellogenin titer and yolk polypeptide pattern of the haemolymph are correlated with the intensity of follicular growth, and the rate of yolk deposition.......During the first egg maturation cycle ofCalliphora vicina changes in the vitellogenin titer and yolk polypeptide pattern of the haemolymph are correlated with the intensity of follicular growth, and the rate of yolk deposition....

  20. A Rationally Designed TNF-α Epitope-Scaffold Immunogen Induces Sustained Antibody Response and Alleviates Collagen-Induced Arthritis in Mice.

    Directory of Open Access Journals (Sweden)

    Li Zhang

    Full Text Available The TNF-α biological inhibitors have significantly improved the clinical outcomes of many autoimmune diseases, in particular rheumatoid arthritis. However, the practical uses are limited due to high costs and the risk of anti-drug antibody responses. Attempts to develop anti-TNF-α vaccines have generated encouraging data in animal models, however, data from clinical trials have not met expectations. In present study, we designed a TNF-α epitope-scaffold immunogen DTNF7 using the transmembrane domain of diphtheria toxin, named DTT as a scaffold. Molecular dynamics simulation shows that the grafted TNF-α epitope is entirely surface-exposed and presented in a native-like conformation while the rigid helical structure of DTT is minimally perturbed, thereby rendering the immunogen highly stable. Immunization of mice with alum formulated DTNF7 induced humoral responses against native TNF-α, and the antibody titer was sustained for more than 6 months, which supports a role of the universal CD4 T cell epitopes of DTT in breaking self-immune tolerance. In a mouse model of rheumatoid arthritis, DTNF7-alum vaccination markedly delayed the onset of collagen-induced arthritis, and reduced incidence as well as clinical score. DTT is presumed safe as an epitope carrier because a catalytic inactive mutant of diphtheria toxin, CRM197 has good clinical safety records as an active vaccine component. Taken all together, we show that DTT-based epitope vaccine is a promising strategy for prevention and treatment of autoimmune diseases.

  1. Anthrax lethal toxin (LeTx) neutralization by PA domain specific antisera.

    Science.gov (United States)

    Verma, Monika; Suryanarayana, Nagendra; Tuteja, Urmil; Thavachelvam, Kulanthaivel; Rao, M K; Bhargava, Rakesh; Shukla, Sangeeta

    2017-12-01

    Anthrax associated causalities in humans and animals are implicated mainly due to the action of two exotoxins that are secreted by the bacterium Bacillus antharcis during the infection. These exotoxins comprise of three protein components namely protective antigen (PA), lethal factor (LF) and edema factor (EF). The protective antigen is the common toxin component required to form both lethal toxin (LeTx) and edema toxin (EdTx). The LeTx is formed, when PA combines with LF and EdTx is formed when PA combines with EF. Therapeutic interventions aiming to neutralize these key effectors of anthrax pathology would therefore, provide an effective means to counter the toxicity imposed by the anthrax toxins on the host. The present work describes the lethal toxin neutralization potential of polyclonal antisera developed against the individual domains of the protective antigen component of the anthrax toxin. The individual domains were produced as recombinant proteins in E. coli and validated with peptide mass fingerprinting by MALDI-TOF analysis and corresponding mice polyclonal antisera by western blotting. Each domain specific antibody titre and isotype was ascertained by ELISA. The isotyping revealed the predominance of IgG1 isotype. The toxin neutralizing potential of these domain specific antisera were evaluated by in-vitro cell viability MTT assay, employing J774.1 mouse macrophage cell line against LeTx (0.25 μg ml -1 PA and 0.125 μg ml -1 LF concentrations). Among the four domain specific antisera, the antiserum against PA domain IV could neutralize LeTx with high efficiency. No significant neutralization of LeTx was observed with other domain specific antibodies. Results indicate that antibodies to r-PA domain IV could be explored further as therapeutic anti toxin molecule along with appropriate antibiotic regimens against anthrax. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Evaluating the synergistic neutralizing effect of anti-botulinum oligoclonal antibody preparations.

    Science.gov (United States)

    Diamant, Eran; Lachmi, Bat-El; Keren, Adi; Barnea, Ada; Marcus, Hadar; Cohen, Shoshana; David, Alon Ben; Zichel, Ran

    2014-01-01

    Botulinum neurotoxins (BoNT) are considered some of the most lethal known substances. There are seven botulinum serotypes, of which types A, B and E cause most human botulism cases. Anti-botulinum polyclonal antibodies (PAbs) are currently used for both detection and treatment of the disease. However, significant improvements in immunoassay specificity and treatment safety may be made using monoclonal antibodies (MAbs). In this study, we present an approach for the simultaneous generation of highly specific and neutralizing MAbs against botulinum serotypes A, B, and E in a single process. The approach relies on immunization of mice with a trivalent mixture of recombinant C-terminal fragment (Hc) of each of the three neurotoxins, followed by a parallel differential robotic hybridoma screening. This strategy enabled the cloning of seven to nine MAbs against each serotype. The majority of the MAbs possessed higher anti-botulinum ELISA titers than anti-botulinum PAbs and had up to five orders of magnitude greater specificity. When tested for their potency in mice, neutralizing MAbs were obtained for all three serotypes and protected against toxin doses of 10 MsLD50-500 MsLD50. A strong synergistic effect of up to 400-fold enhancement in the neutralizing activity was observed when serotype-specific MAbs were combined. Furthermore, the highly protective oligoclonal combinations were as potent as a horse-derived PAb pharmaceutical preparation. Interestingly, MAbs that failed to demonstrate individual neutralizing activity were observed to make a significant contribution to the synergistic effect in the oligoclonal preparation. Together, the trivalent immunization strategy and differential screening approach enabled us to generate highly specific MAbs against each of the A, B, and E BoNTs. These new MAbs may possess diagnostic and therapeutic potential.

  3. Evaluating the synergistic neutralizing effect of anti-botulinum oligoclonal antibody preparations.

    Directory of Open Access Journals (Sweden)

    Eran Diamant

    Full Text Available Botulinum neurotoxins (BoNT are considered some of the most lethal known substances. There are seven botulinum serotypes, of which types A, B and E cause most human botulism cases. Anti-botulinum polyclonal antibodies (PAbs are currently used for both detection and treatment of the disease. However, significant improvements in immunoassay specificity and treatment safety may be made using monoclonal antibodies (MAbs. In this study, we present an approach for the simultaneous generation of highly specific and neutralizing MAbs against botulinum serotypes A, B, and E in a single process. The approach relies on immunization of mice with a trivalent mixture of recombinant C-terminal fragment (Hc of each of the three neurotoxins, followed by a parallel differential robotic hybridoma screening. This strategy enabled the cloning of seven to nine MAbs against each serotype. The majority of the MAbs possessed higher anti-botulinum ELISA titers than anti-botulinum PAbs and had up to five orders of magnitude greater specificity. When tested for their potency in mice, neutralizing MAbs were obtained for all three serotypes and protected against toxin doses of 10 MsLD50-500 MsLD50. A strong synergistic effect of up to 400-fold enhancement in the neutralizing activity was observed when serotype-specific MAbs were combined. Furthermore, the highly protective oligoclonal combinations were as potent as a horse-derived PAb pharmaceutical preparation. Interestingly, MAbs that failed to demonstrate individual neutralizing activity were observed to make a significant contribution to the synergistic effect in the oligoclonal preparation. Together, the trivalent immunization strategy and differential screening approach enabled us to generate highly specific MAbs against each of the A, B, and E BoNTs. These new MAbs may possess diagnostic and therapeutic potential.

  4. Antibody-Conjugated Nanoparticles for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    Manuel Arruebo

    2009-01-01

    Full Text Available Nanoscience and Nanotechnology have found their way into the fields of Biotechnology and Medicine. Nanoparticles by themselves offer specific physicochemical properties that they do not exhibit in bulk form, where materials show constant physical properties regardless of size. Antibodies are nanosize biological products that are part of the specific immune system. In addition to their own properties as pathogens or toxin neutralizers, as well as in the recruitment of immune elements (complement, improving phagocytosis, cytotoxicity antibody dependent by natural killer cells, etc., they could carry several elements (toxins, drugs, fluorochroms, or even nanoparticles, etc. and be used in several diagnostic procedures, or even in therapy to destroy a specific target. The conjugation of antibodies to nanoparticles can generate a product that combines the properties of both. For example, they can combine the small size of nanoparticles and their special thermal, imaging, drug carrier, or magnetic characteristics with the abilities of antibodies, such as specific and selective recognition. The hybrid product will show versatility and specificity. In this review, we analyse both antibodies and nanoparticles, focusing especially on the recent developments for antibody-conjugated nanoparticles, offering the researcher an overview of the different applications and possibilities of these hybrid carriers.

  5. Binding of ATP by pertussis toxin and isolated toxin subunits

    International Nuclear Information System (INIS)

    Hausman, S.Z.; Manclark, C.R.; Burns, D.L.

    1990-01-01

    The binding of ATP to pertussis toxin and its components, the A subunit and B oligomer, was investigated. Whereas, radiolabeled ATP bound to the B oligomer and pertussis toxin, no binding to the A subunit was observed. The binding of [ 3 H]ATP to pertussis toxin and the B oligomer was inhibited by nucleotides. The relative effectiveness of the nucleotides was shown to be ATP > GTP > CTP > TTP for pertussis toxin and ATP > GTP > TTP > CTP for the B oligomer. Phosphate ions inhibited the binding of [ 3 H]ATP to pertussis toxin in a competitive manner; however, the presence of phosphate ions was essential for binding of ATP to the B oligomer. The toxin substrate, NAD, did not affect the binding of [ 3 H]ATP to pertussis toxin, although the glycoprotein fetuin significantly decreased binding. These results suggest that the binding site for ATP is located on the B oligomer and is distinct from the enzymatically active site but may be located near the eukaryotic receptor binding site

  6. Binding of ATP by pertussis toxin and isolated toxin subunits

    Energy Technology Data Exchange (ETDEWEB)

    Hausman, S.Z.; Manclark, C.R.; Burns, D.L. (Center for Biologics Evaluation and Research, Bethesda, MD (USA))

    1990-07-03

    The binding of ATP to pertussis toxin and its components, the A subunit and B oligomer, was investigated. Whereas, radiolabeled ATP bound to the B oligomer and pertussis toxin, no binding to the A subunit was observed. The binding of ({sup 3}H)ATP to pertussis toxin and the B oligomer was inhibited by nucleotides. The relative effectiveness of the nucleotides was shown to be ATP > GTP > CTP > TTP for pertussis toxin and ATP > GTP > TTP > CTP for the B oligomer. Phosphate ions inhibited the binding of ({sup 3}H)ATP to pertussis toxin in a competitive manner; however, the presence of phosphate ions was essential for binding of ATP to the B oligomer. The toxin substrate, NAD, did not affect the binding of ({sup 3}H)ATP to pertussis toxin, although the glycoprotein fetuin significantly decreased binding. These results suggest that the binding site for ATP is located on the B oligomer and is distinct from the enzymatically active site but may be located near the eukaryotic receptor binding site.

  7. Isolation and partial characterization of gypsy moth BTR-270, an anionic brush border membrane glycoconjugate that binds Bacillus thuringiensis Cry1A toxins with high affinity

    Science.gov (United States)

    Algimantas P. Valaitis; Jeremy L. Jenkins; Mi Kyong Lee; Donald H. Dean; Karen J. Garner

    2001-01-01

    BTR-270, a gypsy moth (Lymantria dispar) brush border membrane molecule that binds Bacillus thuringiensis (Bt) Cry1A toxins with high affinity, was purified by preparative gel electrophoresis. Rabbit antibodies specific for the Bt toxin-binding molecule were raised. Attempts to label BTR-270 by protein-directed techniques were...

  8. Antibody response of sandhill and whooping cranes to an eastern equine encephalitis virus vaccine

    Science.gov (United States)

    Clark, G.G.; Dein, F.J.; Crabbs, C.L.; Carpenter, J.W.; Watts, D.M.

    1987-01-01

    As a possible strategy to protect whooping cranes (Grus americana) from fatal eastern equine encephalitis (EEE) viral infection, studies were conducted to determine the immune response of this species and sandhill cranes (Grus canadensis) to a formalin-inactivated EEE viral vaccine. Viral-specific neutralizing antibody was elicited in both species after intramuscular (IM) vaccination. Subcutaneous and intravenous routes of vaccination failed to elicit detectable antibody in sandhill cranes. Among the IM vaccinated cranes, the immune response was characterized by nondetectable or low antibody titers that waned rapidly following primary exposure to the vaccine. However, one or more booster doses consistently elicited detectable antibody and/or increased antibody titers in the whooping cranes. In contrast, cranes with pre-existing EEE viral antibody, apparently induced by natural infection, exhibited a rapid increase and sustained high-antibody titers. Even though EEE virus vaccine induced neutralizing antibody and produced no adverse side effects, further studies will be required to determine the protective efficacy of the antibody.

  9. Diagnostic utility of egg yolk for the detection of avian metapneumovirus antibodies in laying hens.

    Science.gov (United States)

    Choi, Kang-Seuk; Lee, Eun-Kyoung; Jeon, Woo-Jin; Park, Mi-Ja; Yoo, Yae-Na; Kwon, Jun-Hun

    2010-12-01

    Surveillance and diagnosis of avian metapneumovirus (AMPV) infection typically involve measurement of serum antibodies. In the current study, eggs instead of serum samples were used for the detection of AMPV antibodies in egg-laying chicken hens by enzyme-linked immunosorbent assay (ELISA). AMPV-free commercial layer hens were experimentally challenged with AMPV strain SC1509 through intravenous or oculonasal administration. Antibody levels were determined by ELISA. AMPV antibodies were detected in egg yolks from challenged hens by 7 days postinoculation (dpi), with the peak titer at 16 dpi. Antibody levels in eggs laid at 28 dpi correlated well (r = 0.93) with sera taken 28 dpi from the same hens. In a field trial of the yolk ELISA, six broiler breeder farms were surveyed, and all tested positive for AMPV antibodies in hen eggs, although positivity varied from farm to farm. Abnormal discolored eggs collected from outbreak farms had significantly higher titers of AMPV yolk antibodies than normal eggs from the same farm, unlike clinically healthy farms, where normal and abnormal eggs had similar antibody titers. These results indicate that diagnosis of AMPV infection by yolk ELISA to detect anti-AMPV antibodies may be a suitable alternative to serologic testing.

  10. An update on antibody-based immunotherapies for Clostridium difficile infection

    Directory of Open Access Journals (Sweden)

    Hussack G

    2016-08-01

    Full Text Available Greg Hussack,1 Jamshid Tanha1–3 1Human Health Therapeutics Portfolio, National Research Council Canada, Ottawa, 2School of Environmental Sciences, University of Guelph, Guelph, 3Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada Abstract: Clostridium difficile continues to be one of the most prevalent hospital-acquired bacterial infections in the developed world, despite the recent introduction of a novel and effective antibiotic agent (fidaxomicin. Alternative approaches under investigation to combat the anaerobic Gram-positive bacteria include fecal transplantation therapy, vaccines, and antibody-based immunotherapies. In this review, we catalog the recent advances in antibody-based approaches under development and in the clinic for the treatment of C. difficile infection. By and large, inhibitory antibodies that recognize the primary C. difficile virulence factors, toxin A and toxin B, are the most popular passive immunotherapies under investigation. We provide a detailed summary of the toxin epitopes recognized by various antitoxin antibodies and discuss general trends on toxin inhibition efficacy. In addition, antibodies to other C. difficile targets, such as surface-layer proteins, binary toxin, motility factors, and adherence and colonization factors, are introduced in this review. Keywords: antibody, Clostridium difficile, immunotherapy, toxin

  11. Pathogenesis and mechanisms of antibody-mediated hemolysis.

    Science.gov (United States)

    Flegel, Willy A

    2015-07-01

    The clinical consequences of antibodies to red blood cells (RBCs) have been studied for a century. Most clinically relevant antibodies can be detected by sensitive in vitro assays. Several mechanisms of antibody-mediated hemolysis are well understood. Such hemolysis after transfusion is reliably avoided in a donor-recipient pair, if one individual is negative for the cognate antigen to which the other has the antibody. Mechanisms of antibody-mediated hemolysis were reviewed based on a presentation at the Strategies to Address Hemolytic Complications of Immune Globulin Infusions Workshop addressing intravenous immunoglobulin (IVIG) and ABO antibodies. The presented topics included the rates of intravascular and extravascular hemolysis; immunoglobulin (Ig)M and IgG isoagglutinins; auto- and alloantibodies; antibody specificity; A, B, A,B, and A1 antigens; A1 versus A2 phenotypes; monocytes-macrophages, other immune cells, and complement; monocyte monolayer assay; antibody-dependent cell-mediated cytotoxicity; and transfusion reactions due to ABO and other antibodies. Several clinically relevant questions remained unresolved, and diagnostic tools were lacking to routinely and reliably predict the clinical consequences of RBC antibodies. Most hemolytic transfusion reactions associated with IVIG were due to ABO antibodies. Reducing the titers of such antibodies in IVIG may lower the frequency of this kind of adverse event. The only way to stop these events is to have no anti-A or anti-B in the IVIG products. © 2015 AABB.

  12. Genetic relations between natural antibodies binding keyhole limpet hemocyanin and production traits in a purebred layer chicken line.

    Science.gov (United States)

    van der Klein, S A S; Berghof, T V L; Arts, J A J; Parmentier, H K; van der Poel, J J; Bovenhuis, H

    2015-05-01

    Natural antibodies (NAb) are an important component of the first line of immune defense. Selective breeding for enhanced NAb levels in chickens may improve general disease resistance. It is unknown what the consequences of selection for NAb will be on the productive performance of laying hens. In this paper we describe the genetic relations between NAb titers binding keyhole limpet hemocyanin at 19 wk age and production traits in a white purebred leghorn chicken line observed in several time periods. A linear animal model was used to estimate (co)variance components, heritabilities, and correlations. Negative genetic correlations were found between egg weight and NAb titers, and between egg breaking strength and NAb titers. Positive genetic correlations were found between the feed conversion ratio (consumed feed/egg mass produced) and NAb titers, and egg production and NAb titers. Negative phenotypic correlations were found between body weight and NAb titers, between egg weight and NAb titers, and between egg breaking strength and NAb titers. Positive phenotypic correlations were found between egg production and NAb titers, and feed conversion ratio and NAb titers. In general, phenotypic correlations were more often significant, but less pronounced than genetic correlations. Other production traits were not found to be significant related to NAb titers. These findings suggest that there is a genetic tradeoff between levels of immunity and some production traits, although the underlying mechanism(s) remain(s) unclear. The results suggest possible consequences for production efficiency as a result of selective breeding for improved general disease resistance by natural antibodies. © 2015 Poultry Science Association Inc.

  13. Prevalence of antibodies to four human coronaviruses is lower in nasal secretions than in serum.

    Science.gov (United States)

    Gorse, Geoffrey J; Patel, Gira B; Vitale, Joseph N; O'Connor, Theresa Z

    2010-12-01

    Little is known about the prevalence of mucosal antibodies induced by infection with human coronaviruses (HCoV), including HCoV-229E and -OC43 and recently described strains (HCoV-NL63 and -HKU1). By enzyme-linked immunosorbent assay, we measured anti-HCoV IgG antibodies in serum and IgA antibodies in nasal wash specimens collected at seven U.S. sites from 105 adults aged 50 years and older (mean age, 67 ± 9 years) with chronic obstructive pulmonary disease. Most patients (95 [90%]) had at least one more chronic disease. More patients had serum antibody to each HCoV strain (104 [99%] had antibody to HCoV-229E, 105 [100%] had antibody to HCoV-OC43, 103 [98%] had antibody to HCoV-NL63, and 96 [91%] had antibody to HCoV-HKU1) than had antibody to each HCoV strain in nasal wash specimens (12 [11%] had antibody to HCoV-229E, 22 [22%] had antibody to HCoV-OC43, 8 [8%] had antibody to HCoV-NL63, and 31 [31%] had antibody to HCoV-HKU1), respectively (P antibodies in nasal wash specimens and the geometric mean IgA antibody titers were statistically higher for HCoV-OC43 and -HKU1 than for HCoV-229E and -NL63. A higher proportion of patients with heart disease than not had IgA antibodies to HCoV-NL63 (6 [16%] versus 2 [3%]; P = 0.014). Correlations were highest for serum antibody titers between group I strains (HCoV-229E and -NL63 [r = 0.443; P antibodies to these HCoV strains in serum were more likely to be detected than IgA antibodies to these HCoV strains in nasal wash specimens.

  14. Demonstration of carbohydrate-specific immunoglobulin G4 antibodies in sera of patients receiving grass pollen immunotherapy

    NARCIS (Netherlands)

    van Ree, R.; Aalberse, R. C.

    1995-01-01

    From a group of 92 patients receiving grass pollen immunotherapy, and selected on grounds of high IgG4 titers against Lol p I, sera were tested for IgG4 antibodies against the glycosylated grass pollen allergen Lol p XI. In 72 of 92 cases IgG4 antibodies were demonstrated. The N-glycan of Lol p XI

  15. The antibody response in the bovine mammary gland is influenced by the adjuvant and the site of subcutaneous vaccination

    NARCIS (Netherlands)

    Boerhout, Eveline M.; Koets, Ad P.; Mols-Vorstermans, Tanja G.T.; Nuijten, Piet J.M.; Hoeijmakers, Mathieu J.H.; Rutten, Victor P.M.G.; Bijlsma, Jetta J.E.

    2018-01-01

    Intramammary infections in cattle resulting in mastitis have detrimental effects on cows' well-being, lifespan and milk production. In the host defense against S. aureus mastitis antibodies are thought to play an important role. To explore potential ways to increase antibody titers in the bovine

  16. Food toxin detection with atomic force microscope

    Science.gov (United States)

    Externally introduced toxins or internal spoilage correlated pathogens and their metabolites are all potential sources of food toxins. To prevent and protect unsafe food, many food toxin detection techniques have been developed to detect various toxins for quality control. Although several routine m...

  17. A High-Throughput, Precipitating Colorimetric Sandwich ELISA Microarray for Shiga Toxins

    Directory of Open Access Journals (Sweden)

    Andrew Gehring

    2014-06-01

    Full Text Available Shiga toxins 1 and 2 (Stx1 and Stx2 from Shiga toxin-producing E. coli (STEC bacteria were simultaneously detected with a newly developed, high-throughput antibody microarray platform. The proteinaceous toxins were immobilized and sandwiched between biorecognition elements (monoclonal antibodies and pooled horseradish peroxidase (HRP-conjugated monoclonal antibodies. Following the reaction of HRP with the precipitating chromogenic substrate (metal enhanced 3,3-diaminobenzidine tetrahydrochloride or DAB, the formation of a colored product was quantitatively measured with an inexpensive flatbed page scanner. The colorimetric ELISA microarray was demonstrated to detect Stx1 and Stx2 at levels as low as ~4.5 ng/mL within ~2 h of total assay time with a narrow linear dynamic range of ~1–2 orders of magnitude and saturation levels well above background. Stx1 and/or Stx2 produced by various strains of STEC were also detected following the treatment of cultured cells with mitomycin C (a toxin-inducing antibiotic and/or B-PER (a cell-disrupting, protein extraction reagent. Semi-quantitative detection of Shiga toxins was demonstrated to be sporadic among various STEC strains following incubation with mitomycin C; however, further reaction with B-PER generally resulted in the detection of or increased detection of Stx1, relative to Stx2, produced by STECs inoculated into either axenic broth culture or culture broth containing ground beef.

  18. Human Monoclonal Antibodies as a Countermeasure Against Botulinum Toxins

    Science.gov (United States)

    2012-11-30

    eukaryotic scaffolds for production of trivalent neutralizing constructs. In both prokaryotic methods (in-line Fv and triabodies), reactivity against...BoNTs could be observed, but either the affinities or percentage of correctly folded material negated their further study. In eukaryotic (293F) cells ...proposal that linking IgG/M heavy and light chains in eukaryotic cells would ensure correct pairing for BoNT reactivity, we wished to 0 24 48 72 96 0

  19. Development of an ELISA microarray assay for the sensitive and simultaneous detection of ten biodefense toxins.

    Energy Technology Data Exchange (ETDEWEB)

    Jenko, Kathryn; Zhang, Yanfeng; Kostenko, Yulia; Fan, Yongfeng; Garcia-Rodriguez, Consuelo; Lou, Jianlong; Marks, James D.; Varnum, Susan M.

    2014-10-21

    Plant and microbial toxins are considered bioterrorism threat agents because of their extreme toxicity and/or ease of availability. Additionally, some of these toxins are increasingly responsible for accidental food poisonings. The current study utilized an ELISA-based protein antibody microarray for the multiplexed detection of ten biothreat toxins, botulinum neurotoxins (BoNT) A, B, C, D, E, F, ricin, shiga toxins 1 and 2 (Stx), and staphylococcus enterotoxin B (SEB), in buffer and complex biological matrices. The multiplexed assay displayed a sensitivity of 1.3 pg/mL (BoNT/A, BoNT/B, SEB, Stx-1 and Stx-2), 3.3 pg/mL (BoNT/C, BoNT/E, BoNT/F) and 8.2 pg/mL (BoNT/D, ricin). All assays demonstrated high accuracy (75-120 percent recovery) and reproducibility (most coefficients of variation < 20%). Quantification curves for the ten toxins were also evaluated in clinical samples (serum, plasma, nasal fluid, saliva, stool, and urine) and environmental samples (apple juice, milk and baby food) with overall minimal matrix effects. The multiplex assays were highly specific, with little crossreactivity observed between the selected toxin antibodies. The results demonstrate a multiplex microarray that improves current immunoassay sensitivity for biological warfare agents in buffer, clinical, and environmental samples.

  20. Antibodies against Hepatitis A and Hepatitis B Virus in Intravenous Immunoglobulin Products.

    Science.gov (United States)

    Lee, Soyoung; Kim, Han Wool; Kim, Kyung Hyo

    2016-12-01

    The worldwide seroprevalence of hepatitis A virus (HAV) and hepatitis B virus (HBV) has changed over the last two decades, indicating a declining incidence of HAV and HBV infections. Therefore, vaccinations against HAV and HBV are recommended for unimmunized people before traveling to an endemic area. Unfortunately, primary antibody deficiency (PAD) patients can only obtain humoral immunity through intravenous immunoglobulin G (IVIG) replacement and not from vaccination because of a defect in antibody production. However, few studies have analyzed the titers of antibodies against HAV or HBV in IVIG products. In this study, the titers of anti-HAV and anti-HBs antibodies were measured in nineteen lots of IVIG products from five manufacturers from three countries (A, B from Korea; C, D from Japan; and E from the USA), and trough titers in plasma were estimated. Concentrations of anti-HAV antibody ranged from 1,888-8,927 mIU/mL and estimated trough titers exceeded the minimal protective value in all evaluated IVIG products. Concentrations of anti-HBs antibody ranged from 438-965 mIU/mL in products A and B and were 157, 123, and 1,945 mIU/mL in products C, D, and E, respectively. Estimated trough titers in products A, B, and E exceeded the minimal protective value but those in products C and D did not reach this threshold. These data demonstrated that available IVIG products generally provide sufficient antibodies against HAV and HBV to protect patients with PAD, although the trough concentrations of anti-HBs antibody in two IVIG products did not reach the minimum protective value.

  1. Occurrence of antibodies to Toxoplasma gondii in rheas (Rhea americana and ostriches (Struthio camelus from farms of different Brazilian regions

    Directory of Open Access Journals (Sweden)

    Amanda Brentano Almeida

    Full Text Available This study aimed to verify the occurrence of antibodies againstToxoplasma gondii in rheas (Rhea americana and ostriches (Struthio camelus commercially breeding in Brazil. Blood samples from 20 rheas and 46 ostriches (young and adults were serologically tested using a technique known as modified agglutination test (MAT at an initial titration of 1:16 for ostriches and 1:25 for rheas. Antibodies against T. gondii were found in 50% (10/20 of the rheas, with titers ranging from 1:25 to 1:6,400. The incidence of antibodies against T. gondii in ostriches was 17.4% (8/46 with titers ranging from 1:16 to 1:256. Birds showing titers higher than 1:200 forT. gondii were mainly the young ones. Therefore, rheas and ostriches may be parasitized by T. gondii, showing high levels of antibodies against this parasite.

  2. Oral lichen planus with antibodies to desmogleins 1 and 3.

    Science.gov (United States)

    Kinjyo, Chihiro; Kaneko, Takahide; Korekawa, Ayumi; Rokunohe, Akiko; Aizu, Takayuki; Matsuzaki, Yasushi; Nakano, Hajime; Sawamura, Daisuke

    2015-01-01

    Lichen planus (LP) is a chronic inflammatory disorder involving the skin or mucous membranes. Previous studies have demonstrated that some LP patients showed positive enzyme-linked immunosorbent assay (ELISA) for desmoglein (DSG) antibodies. We report a case with intractable painful oral lesions. ELISA indices for DSG1 and 3 antibodies were increased by 49 and 36, respectively. Histopathological analysis revealed irregular acanthosis and band-like infiltration of lymphocytes at the dermal-epidermal interface. Direct immunofluorescence revealed negative deposits of immunoglobulin G and C3 in intracellular spaces of the epidermis. Indirect immunofluorescence of normal skin also did not detect any antibodies. Consequently, we made a final diagnosis of oral LP. The previous two LP cases with positive ELISA for DSG antibodies and our case manifested the erosive form, the most advanced oral LP. Therefore, it is a possibility that severe damage of keratinocytes may induce generation of DSG antibodies. However, negative results of immunofluorescence and no relation between disease severity and titers of antibodies make the possibility unlikely. We should measure titers of DSG antibodies in LP patients and accumulate data to establish a valid conclusion. © 2014 Japanese Dermatological Association.

  3. Cambridge Healthtech Institute's 4th Annual Recombinant Antibodies Conference.

    Science.gov (United States)

    Casey, Joanne L; Coley, Andrew M

    2003-08-01

    The 4th Annual Recombinant Antibodies Conference was immediately following the 5th Annual 'Molecular Display: The Chemistry Set for Proteins and Small Molecules' conference, both held in Cambridge, MA and organised by Cambridge Healthtech Institute. The former conference focused on development of new approaches for recombinant antibody development, with particular emphasis on improved methods for selection and optimisation allowing rapid validation and development of human antibodies for the clinic. There were many impressive presentations describing emerging technologies such as new antibody-like scaffolds, covalent P2 antibody display, de-immunisation of antibodies and measuring affinities of as many as 400 clones simultaneously using proteomic microarray platforms. The conference also highlighted the latest applications of library technologies for proteomics and target discovery, and the generation of therapeutic molecules as antibodies alone or as drug, toxin or radionuclide conjugates.

  4. A flow cytometric protocol for titering recombinant adenoviral vectors containing the green fluorescent protein.

    Science.gov (United States)

    Hitt, D C; Booth, J L; Dandapani, V; Pennington, L R; Gimble, J M; Metcalf, J

    2000-03-01

    As the use of adenoviral vectors in gene therapy protocols increases, there is a corresponding need for rapid, accurate, and reproducible titer methods. Multiple methods currently exist for determining titers of recombinant adenoviral vector, including optical absorbance, electron microscopy, fluorescent focus assay, and the "gold standard" plaque assay. This paper introduces a novel flow cytometric method for direct titer determination that relies on the expression of the green fluorescent protein (GFP), a tracking marker incorporated into several adenoviral vectors. This approach was compared to the plaque assay using 10(-4)- to 10(-6)-fold dilutions of a cesium-chloride-purified, GFP expressing adenovirus (AdEasy + GFP + GAL). The two approaches yielded similar titers: 3.25 +/- 1.85 x 10(9) PFU/mL versus 3.46 +/- 0.76 x 10(9) green fluorescent units/(gfu/mL). The flow cytometric method is complete within 24 h in contrast to the 7 x 10 days required by the plaque assay. These results indicate that the GFU/mL is an alternative functional titer method for fluorescent-tagged adenoviral vectors.

  5. Toxins: State of Journal Report, 2016

    Directory of Open Access Journals (Sweden)

    Vernon L. Tesh

    2015-12-01

    Full Text Available In the “Message from the Editor-in-Chief” posted on the Toxins website (see www.mdpi.com/journal/toxins/toxins-flyer.pdf, we wrote: “The editorial board and staff of Toxins are dedicated to providing a timely, peer-reviewed outlet for exciting, innovative primary research articles and concise, informative reviews from investigators in the myriad of disciplines contributing to our knowledge on toxins. [...

  6. Evaluation of Vaccine-induced Antibody Responses: Impact of New Technologies

    Science.gov (United States)

    Zaccaro, Daniel J.; Wagener, Diane K.; Whisnant, Carol C.; Staats, Herman F.

    2013-01-01

    Host response to vaccination has historically been evaluated based on a change in antibody titer that compares the post-vaccination titer to the pre-vaccination titer. A four-fold or greater increase in antigen-specific antibody has been interpreted to indicate an increase in antibody production in response to vaccination. New technologies, such as the bead-based assays, provide investigators and clinicians with precise antibody levels (reported as concentration per mL) in ranges below and above those previously available through standard assays such as ELISA. Evaluations of bead assay data to determine host response to vaccination using fold change and absolute change, witha general linear models used to calculate adjusted statistics, present very different pictures of the antibody response when pre-vaccination antibody levels are low. Absolute changes in bead assay values, although not a standard computation, appears to more accurately reflect the host response to vaccination for those individuals with extremely low pre-vaccination antibody levels. Conversely, for these same individuals, fold change may be very high while post-vaccination antibodies do not achieve seroprotective levels. Absolute change provides an alternate method to characterize host response to vaccination, especially when pre-vaccination levels are very low, and may be useful in studies designed to determine associations between host genotypes and response to vaccination. PMID:23583812

  7. Novel techniques for volume management and toxin removal in end-stage renal disease

    NARCIS (Netherlands)

    Brummelhuis, W.J.

    2010-01-01

    This first part of this thesis, ’Removing substances’, describes a novel immunoadsorption technique that uses variable domains of heavy chain llama antibodies (VHH) to remove a toxic agent, Toxic Shock Syndrome Toxin-1 (TSST-1) from the circulation. This study was designed as a proof-of-principle

  8. Coeliac disease - clinical presentation and diagnosis by anti tissue transglutaminase antibodies titre in children

    International Nuclear Information System (INIS)

    Hussain, S.; Sabir, M.U.D.; Afzal, M.; Asghar, I.

    2014-01-01

    Objective: To study the spectrum of clinical presentation of coeliac disease and the role of IgA anti-tissue transglutaminase antibodies titer in the diagnosis and effect of gluten-free diet on such titers in children. Methods: The prospective study was conducted in the paediatric department of Combined Military Hospital, Kharian from Sep 2011 to Sep 2012. Children of 1-12 years of age presenting with chronic diarrhoea, malnutrition and failure to thrive were included regardless of gender, socioeconomic status, ethnicity and geographical distribution. Anti-tissue transglutaminase antibodies titers were done on enrolment. Patients with levels more than 30u/ml were enrolled. They were advised strict gluten-free diet for six months. These titers were repeated after six months to document the effect of gluten-free diet on these titers. Paediatric endoscopy and duodenal biopsy facilities were not available at the study site, so the response was monitored through titers. Data was analysed using SPSS-20. Results: Out of 61 patients with IgA levels more than 10 u/ml, 52 (85.24%) were found to have a positive (>30u/ml) anti-tissue transglutaminase antibodies titers with a mean value of 42.67+-7.60 U/ml. These 52 patients were then put on a trial of gluten-free diet for six months after which significant reduction in titer was noticed, with a mean value of 13.25+-2.59 U/ml. This reduction in titer was associated with marked clinical improvement and regression of symptoms. Frequency of different clinical features in descending order revealed that chronic diarrhoea, abdominal distension, iron deficiency anaemia, failure to thrive, pallor and rickets were present in 38 (73.1%), 30 (57.7%), 29 (55.8%), 29 (53.8%), 28 (53.8%) patients respectively. Conclusion: Chronic diarrhoea, failure to thrive, pallor, abdominal distention and iron deficiency anaemia were common modes of presentation. The antibodies were strongly positive in most of the cases. All children showed significant

  9. Bio Warfare and Terrorism: Toxins and Other Mid-Spectrum Agents

    National Research Council Canada - National Science Library

    Madsen, James M

    2005-01-01

    ... counterparts are still by definition toxins. Related terms include phycotoxins (toxins from algae), mycotoxins (fungal toxins), phytotoxins (plant toxins), and venoms (toxins from animals, especially vertebrates...

  10. Application of the polymerase chain reaction in determination of recombinant retrovirus titers as fifty percent endpoints

    DEFF Research Database (Denmark)

    Husemoen, L L; Gram, G J; Hansen, J E

    2000-01-01

    -based protocols that would significantly simplify and shorten this procedure. Using PCR and primers specific for the Neoregion of the MLV-derived vector LeGSN, we determined 1. the proviral integration in target cells, and 2. the viral nucleic acid (RNA or DNA) content of the vector stock. Results were compared......, determination of virus titer involves the testing of culture medium from individual packaging cell lines for the ability to transfer drug resistance to susceptible cells - a process that can easily take up to 14 days. It is generally agreed that this method is cumbersome. We sought to develop PCR...... with those using the conventional method. We found that these specific PCR-based procedures were indeed useful for rapid determination of viral titers as well as for quick screening for high-titer vector-producing cell clones and successful transduction of target cells....

  11. High-titer production of monomeric hydroxyvalerates from levulinic acid in Pseudomonas putida.

    Science.gov (United States)

    Martin, Collin H; Prather, Kristala L Jones

    2009-01-01

    Hydroxyacids represent an important class of compounds that see application in the production of polyesters, biodegradable plastics and antibiotics, and that serve as useful chiral synthetic building blocks for other fine chemicals and pharmaceuticals. An economical, high-titer method for the production of 4-hydroxyvalerate (4HV) and 3-hydroxyvalerate (3HV) from the inexpensive and renewable carbon source levulinic acid was developed. These hydroxyvalerates were produced by periodically feeding levulinate to Pseudomonas putida KT2440 expressing a recombinant thioesterase II (tesB) gene from Escherichia coli K12. The titer of 4HV in shake flask culture reached 13.9+/-1.2 g L(-1) from P. putida tesB(+) cultured at 32 degrees C in LB medium periodically supplemented with glucose and levulinate. The highest 3HV titer obtained was 5.3+/-0.1 g L(-1) in M9 minimal medium supplemented with glucose and levulinate.

  12. Quantitative Mass Spectrometry for Bacterial Protein Toxins — A Sensitive, Specific, High-Throughput Tool for Detection and Diagnosis

    Directory of Open Access Journals (Sweden)

    Suzanne Kalb

    2011-03-01

    Full Text Available Matrix-assisted laser-desorption time-of-flight (MALDI-TOF mass spectrometry (MS is a valuable high-throughput tool for peptide analysis. Liquid chromatography electrospray ionization (LC-ESI tandem-MS provides sensitive and specific quantification of small molecules and peptides. The high analytic power of MS coupled with high-specificity substrates is ideally suited for detection and quantification of bacterial enzymatic activities. As specific examples of the MS applications in disease diagnosis and select agent detection, we describe recent advances in the analyses of two high profile protein toxin groups, the Bacillus anthracis toxins and the Clostridium botulinum neurotoxins. The two binary toxins produced by B. anthracis consist of protective antigen (PA which combines with lethal factor (LF and edema factor (EF, forming lethal toxin and edema toxin respectively. LF is a zinc-dependent endoprotease which hydrolyzes specific proteins involved in inflammation and immunity. EF is an adenylyl cyclase which converts ATP to cyclic-AMP. Toxin-specific enzyme activity for a strategically designed substrate, amplifies reaction products which are detected by MALDI-TOF-MS and LC-ESI-MS/MS. Pre-concentration/purification with toxin specific monoclonal antibodies provides additional specificity. These combined technologies have achieved high specificity, ultrasensitive detection and quantification of the anthrax toxins. We also describe potential applications to diseases of high public health impact, including Clostridium difficile glucosylating toxins and the Bordetella pertussis adenylyl cyclase.

  13. Detection of Shiga Toxins by Lateral Flow Assay

    Directory of Open Access Journals (Sweden)

    Kathryn H. Ching

    2015-04-01

    Full Text Available Shiga toxin-producing Escherichia coli (STEC produce shiga toxins (Stxs that can cause human disease and death. The contamination of food products with STEC represents a food safety problem that necessitates rapid and effective detection strategies to mitigate risk. In this manuscript, we report the development of a colorimetric lateral flow assay (LFA for the rapid detection of Stxs in <10 min using a pair of monoclonal antibodies that bind epitopes common to Stx1 and six Stx2 variants. This LFA provides a rapid and sensitive test for the detection of Stxs directly from STEC culture supernatants or at risk food samples with a 0.1 ng/mL limit of detection (LOD for Stx2a. This Stx LFA is applicable for use in the rapid evaluation of Stx production from cultured E. coli strains or as a tool to augment current methods as part of food safety testing.

  14. Drug-induced Hypersensitivity Syndrome Associated with a Marked Increase in Anti-paramyxovirus Antibody Titers in a Scleroderma Patient

    Directory of Open Access Journals (Sweden)

    Taio Naniwa

    2007-01-01

    Discussion: These findings suggest that paramyxovirus infection had contributed to the development of DIHS in this patient and that there is a need to seek evidence of other viral infections in some cases of DIHS, especially those without herpes virus reactivation/infection.

  15. Single immunization with a suboptimal antigen dose encapsulated into polyanhydride microparticles promotes high titer and avid antibody responses

    Science.gov (United States)

    Microparticle adjuvants based on biodegradable polyanhydrides were used to provide controlled delivery of a model antigen, ovalbumin (Ova), to mice. Ova was encapsulated into two different polyanhydride microparticle formulations to evaluate the influence of polymer chemistry on the nature and magn...

  16. Antibody titers against swine influenza subtypes determined by the hemagglutination inhibition test are highly dependent on the strain

    DEFF Research Database (Denmark)

    Trebbien, Ramona; Nielsen, Jens; Bøtner, Anette

    In Denmark there are three circulating strains of swine influenza H1N1, H1N2 and H3N2. The H1N2 is different from the H1N2 subtypes circulating in other European countries. The Danish subtype is a reassortment between the two Danish circulating swine influenza subtypes H1N1 and H3N2. From...

  17. Increased serum anti-mycobacterial antibody titers in rheumatoid arthritis patients: Is there any specific antigenic target?

    International Nuclear Information System (INIS)

    Cetin, Emel S.; Aksoy, Ali M

    2007-01-01

    Objective was to investigate the presence of immunoreactivity against mycobacterial antigens in the sera of patients with rheumatoid arthritis (Ra) and to detect the target of the immune reaction. This study was carried out on 60 patients with RA, and 25 patients with no joint diseases in the laboratory of Clinical Microbiology Department of Ankara University Medical Faculty, Ankara, Turkey between July 2003 to January 2004. Secreted and cellular antigens of Mycobacterium tuberculosis (M. tuberculosis) H37Rv and Mycobacterium bovis (M. bovis) were isolated and purified by high performance liquid chromatography to antigenic fractions. The immunoreactivity of patient and control sera against these antigens were determined by enzyme-linked immunosorbent assay (ELISA). Immunoreactivity against mycobacterial antigens in RA patients were significantly higher than controls. Significant difference between patients and controls has been determined with M. bovis Bacillus Calmette Guerin (BCG) culture fluid and sonicate antigens, but not with M. tuberculosis H37Rv. This suggests that the antigen triggering immune response in patients with RA may belong to or mainly expressed on M. bovis BCG. The ELISA results showed significant difference between RA patients and controls with all antigenic fractions. Presence of increased immunoreactivity against mycobacterial antigens in the sera of patients with RA was detected. When statistical analysis was considered, we cannot put forward any antigenic fraction alone as the one responsible for the increased reactivity. (author)

  18. OBJECTIVE QUANTITATION OF SERUM ANTIBODY-TITERS AGAINST ENTEROBACTERIACEAE USING INDIRECT IMMUNOFLUORESCENCE, READ BY VIDEOCAMERA AND IMAGE-PROCESSING SYSTEM

    NARCIS (Netherlands)

    APPERLOORENKEMA, HZ; WILKINSON, MHF; OENEMA, DG; VANDERWAAIJ, D

    1991-01-01

    A new way of measuring indirect immunofluorescence (IIF) of microscopic bacterial slide preparations by videocamera and an image processing system is presented. This method is compared with the conventional method of reading the slides by eye. The advantages of this new approach are objective

  19. Decreased vaccine antibody titers following exposure to multiple metals and metalloids in e-waste-exposed preschool children

    NARCIS (Netherlands)

    Lin, Xinjiang; Xu, Xijin; Zeng, Xiang; Xu, Long; Zeng, Zhijun; Huo, Xia

    We explored acquired immunity resulting from vaccination in 3 to 7-year-old children, chronically exposed to multiple heavy metals and metalloids, in an e-waste recycling area (Guiyu, China). Child blood levels of ten heavy metals and metalloids, including lead (Pb), arsenic (As), mercury (Hg),

  20. Evidence that active protection following oral immunization of mice with live rotavirus is not dependent on neutralizing antibody.

    Science.gov (United States)

    Ward, R L; McNeal, M M; Sheridan, J F

    1992-05-01

    Studies were performed to determine whether active immunity against murine rotavirus (EDIM) infection of mice correlated with titers of neutralizing antibody to the challenge virus. Neonatal mice administered either murine or heterologous rotaviruses all developed diarrhea and high titers of serum rotavirus IgG. However, only mice given EDIM, the murine EB, or simian SA11-FEM strains were protected against EDIM infection when challenged 60 days later. Other serotype 3 strains (RRV, SA11-SEM), as well as strains belonging to serotypes 5 and 6 (OSU, NCDV, WC3), were not protective. Serum neutralizing antibody titers to EDIM were almost undetectable after rotavirus infection with any strain and could not, therefore, be correlated with protection. Likewise, intestinal neutralizing antibody titers were extremely low 21 days after EDIM infection, and by 60 days after inoculation, EDIM-infected mice had no greater intestinal neutralizing antibody titers than uninoculated controls. Mice inoculated with SA11-FEM as neonates had much higher serum rotavirus IgG responses than mice inoculated as adults, and only those infected with this virus as neonates were protected. Thus, although immunity to EDIM did not correlate with the presence of neutralizing antibody to EDIM, it did correlate with the overall magnitude of the immune response after inoculation with SA11-FEM.

  1. Durability of Vaccine-Induced Immunity Against Tetanus and Diphtheria Toxins: A Cross-sectional Analysis

    Science.gov (United States)

    Hammarlund, Erika; Thomas, Archana; Poore, Elizabeth A.; Amanna, Ian J.; Rynko, Abby E.; Mori, Motomi; Chen, Zunqiu; Slifka, Mark K.

    2016-01-01

    Background. Many adult immunization schedules recommend that tetanus and diphtheria vaccination be performed every 10 years. In light of current epidemiological trends of disease incidence and rates of vaccine-associated adverse events, the 10-year revaccination schedule has come into question. Methods. We performed cross-sectional analysis of serum antibody titers in 546 adult subjects stratified by age or sex. All serological results were converted to international units after calibration with international serum standards. Results. Approximately 97% of the population was seropositive to tetanus and diphtheria as defined by a protective serum antibody titer of ≥0.01 IU/mL. Mean antibody titers were 3.6 and 0.35 IU/mL against tetanus and diphtheria, respectively. Antibody responses to tetanus declined with an estimated half-life of 14 years (95% confidence interval, 11–17 years), whereas antibody responses to diphtheria were more long-lived and declined with an estimated half-life of 27 years (18–51 years). Mathematical models combining antibody magnitude and duration predict that 95% of the population will remain protected against tetanus and diphtheria for ≥30 years without requiring further booster vaccination. Conclusions. These studies demonstrate that durable levels of protective antitoxin immunity exist in the majority of vaccinated individuals. Together, this suggests that it may no longer be necessary to administer booster vaccinations every 10 years and that the current adult vaccination schedule for tetanus and diphtheria should be revisited. PMID:27060790

  2. Characterization of Am IT, an anti-insect β-toxin isolated from the venom of scorpion Androctonus mauretanicus.

    Science.gov (United States)

    Oukkache, Naoual; ElJaoudi, Rachid; Chgoury, Fatima; Rocha, Marisa Teixeira; Sabatier, Jean-Marc

    2015-06-25

    In the present study, a 'novel' toxin, called Am IT from the venom of scorpion Androctonus mauretanicus is isolated and characterized. A detailed analysis of the action of Am IT on insect axonal sodium currents is reported. Am IT was purified through gel filtration followed by C18 reversed-phase HPLC. Toxicity of Am IT in vivo was assessed on male German cockroach (Blattella germanica) larvae and C57/BL6 mice. Cross-reactivity of Am IT with two β-toxins was evidenced using (125)I-iodinated toxin-based radioimmunoassays with synaptosomal preparations from rat brain. The complete amino acid sequence of Am IT was finally determined by Edman sequencing. Am IT was observed to compete with AaH IT4 purified from the venom of scorpion Androctonus australis in binding assays. It was recognized by an antibody raised against a β-type toxin, which indicated some structural similarity with β-toxins (or related toxin family). The 'novel' toxin exhibited dual activity since it competed with anti-mammal toxins in binding assays as well as showed contracting activity to insect. The toxin competed with radio-labeled β-toxin Css IV by binding to Na(+) channels of rat brain synaptosomes. Analysis of toxin amino acid sequences showed that Am IT shares high structural identity (92%) with AaH IT4. In conclusion, Am IT not only reveals an anti-insect compound properties secreted by 'Old World' scorpions, paralyzing insect larvae by binding to Na(+) channels on larvae's nerve-cell membranes, but also exerts toxic activity in mice, which is similar to anti-mammal toxins from 'New World' scorpions (North and South Americas). Therefore, Am IT appears to be structurally and functionally similar to AaH IT4.

  3. Serum antibodies to periodontal bacteria as diagnostic markers of periodontitis.

    Science.gov (United States)

    Dye, Bruce A; Herrera-Abreu, Miriam; Lerche-Sehm, Julia; Vlachojannis, Christian; Pikdoken, Levent; Pretzl, Bernadette; Schwartz, Aaron; Papapanou, Panos N

    2009-04-01

    Assessment of periodontal conditions in epidemiologic studies usually requires a clinical examination, which is resource-intensive. We investigated the ability of serum immunoglobulin G (IgG) antibodies to periodontal bacteria to reflect clinical periodontal status. We used checkerboard immunoblotting to assess serum IgG levels to 19 species, including established/putative periodontal pathogens and non-pathogenic bacteria, in 5,747 dentate adults aged > or = 40 years who participated in the third National Health and Nutrition Examination Survey between 1988 and 1994. Three earlier described alternative definitions of periodontitis were used, based on specific combinations of probing depth and attachment level values. Optimized elevated titer thresholds and corresponding sensitivities and specificities were calculated for each definition. Titers significantly associated with periodontitis were identified in univariable and multivariable logistic regression models. Parsimonious models were subsequently developed using age, gender, race/ethnicity, education, smoking, and diagnosed diabetes. In unadjusted models, high titers to Porphyromonas gingivalis were most strongly associated with periodontitis across all definitions (odds ratio, 2.07 to 2.74; P periodontitis, whereas high Eubacterium nodatum titers were associated with periodontal health in two of three definitions. Receiver operating characteristic curves for the parsimonious multivariable models showed that the area under the curve ranged between 0.72 and 0.78. Serum IgG titers to selected periodontal species, combined with demographic and behavioral characteristics, resulted in a moderately accurate classification of periodontal status in epidemiologic studies. The external validity of these findings must be examined further.

  4. Age affects quantity but not quality of antibody responses after vaccination with an inactivated flavivirus vaccine against tick-borne encephalitis.

    Directory of Open Access Journals (Sweden)

    Karin Stiasny

    Full Text Available The impairment of immune functions in the elderly (immunosenescence results in post-vaccination antibody titers that are significantly lower than in young individuals. It is, however, a controversial question whether also the quality of antibodies declines with age. In this study, we have therefore investigated the age-dependence of functional characteristics of antibody responses induced by vaccination with an inactivated flavivirus vaccine against tick-borne encephalitis (TBE. For this purpose, we quantified TBE virus-specific IgG and neutralizing antibody titers in post-vaccination sera from groups of young and elderly healthy adults and determined antibody avidities and NT/ELISA titer ratios (functional activity. In contrast to the quantitative impairment of antibody production in the elderly, we found no age-related differences in the avidity and functional activity of antibodies induced by vaccination, which also appeared to be independent of the age at primary immunization. There was no correlation between antibody avidity and NT/ELISA ratios suggesting that additional factors affect the quality of polyclonal responses, independent of age. Our work indicates that healthy elderly people are able to produce antibodies in response to vaccination with similar avidity and functional activity as young individuals, albeit at lower titers.

  5. Catalytic Antibodies

    Indian Academy of Sciences (India)

    The ability of the highly evolved machinery of immune system to produce structurally and functionally complex ... to Pauling, if the structure of the antigen binding site of antibodies were to be produced in a random ..... where the immune system of the body is destructive, as in autoimmune disorders or after organ transplant.

  6. Catalytic Antibodies

    Indian Academy of Sciences (India)

    While chemistry provides the framework for understanding the structure and function of biomolecules, the immune sys- tem provides a highly evolved natural process to generate one class of complex biomolecules – the antibodies. A combination of the two could be exploited to generate new classes of molecules with novel ...

  7. Antiphospholipid antibodies in Brazilian hepatitis C virus carriers

    Directory of Open Access Journals (Sweden)

    A.M. Atta

    2008-06-01

    Full Text Available Hepatitis C, a worldwide viral infection, is an important health problem in Brazil. The virus causes chronic infection, provoking B lymphocyte dysfunction, as represented by cryoglobulinemia, non-organ-specific autoantibody production, and non-Hodgkin's lymphoma. The aim of this research was to screen for the presence of antiphospholipid autoantibodies in 109 Brazilian hepatitis C virus carriers without clinical history of antiphospholipid syndrome. Forty healthy individuals were used as the control group. IgA, IgG, and IgM antibodies against cardiolipin and β2-glycoprotein I were measured with an enzyme-linked immunosorbent assay, using a cut-off point of either 20 UPL or 20 SBU. While 24 (22.0% hepatitis C carriers had moderate titers of IgM anticardiolipin antibodies (median, 22.5 MPL; 95%CI: 21.5-25.4 MPL, only three carriers (<3% had IgG anticardiolipin antibodies (median, 23 GPL; 95%CI: 20.5-25.5 GPL. Furthermore, IgA anticardiolipin antibodies were not detected in these individuals. Male gender and IgM anticardiolipin seropositivity were associated in the hepatitis C group (P = 0.0004. IgA anti-β2-glycoprotein-I antibodies were detected in 29 of 109 (27.0% hepatitis C carriers (median, 41 SAU; 95%CI: 52.7-103.9 SAU. Twenty patients (18.0% had IgM anti-β2-glycoprotein I antibodies (median, 27.6 SMU; 95%CI: 23.3-70.3 SMU, while two patients had IgG antibodies against this protein (titers, 33 and 78 SGU. Antiphospholipid antibodies were detected in only one healthy individual, who was seropositive for IgM anticardiolipin. We concluded that Brazilian individuals chronically infected with hepatitis C virus present a significant production of antiphospholipid antibodies, mainly IgA anti-β2-glycoprotein I antibodies, which are not associated with clinical manifestations of antiphospholipid syndrome.

  8. Presence of Autoimmune Antibody in Chikungunya Infection

    Directory of Open Access Journals (Sweden)

    Wirach Maek-a-nantawat

    2009-01-01

    Full Text Available Chikungunya infection has recently re-emerged as an important arthropod-borne disease in Thailand. Recently, Southern Thailand was identified as a potentially endemic area for the chikungunya virus. Here, we report a case of severe musculoskeletal complication, presenting with muscle weakness and swelling of the limbs. During the investigation to exclude autoimmune muscular inflammation, high titers of antinuclear antibody were detected. This is the report of autoimmunity detection associated with an arbovirus infection. The symptoms can mimic autoimmune polymyositis disease, and the condition requires close monitoring before deciding to embark upon prolonged specific treatment with immunomodulators.

  9. The IgM Response to Modified LDL in Experimental Atherosclerosis Hypochlorite-modified LDL IgM Antibodies versus Classical Natural T15 IgM Antibodies

    NARCIS (Netherlands)

    van Leeuwen, Marcella; Damoiseaux, Jan; Duijvestijn, Adriaan; Heeringa, Peter; Gijbels, Marion; de Winther, Menno; Tervaert, Jan Willem Cohen; Shoenfeld, Y; Gershwin, ME

    2009-01-01

    Introduction: It is hypothesized that IgM antibodies to oxidized LDL are anti-atherogenic. Myeloperoxidase from plaque-infiltrating neutrophils catalyzes the production of hypochlorite (HOCl), which oxidizes LDL. Here we study the IgM response to HOCl-modified LDL in comparison to titers of T15

  10. Phage-Mediated Competitive Chemiluminescent Immunoassay for Detecting Cry1Ab Toxin by Using an Anti-Idiotypic Camel Nanobody.

    Science.gov (United States)

    Qiu, Yulou; Li, Pan; Dong, Sa; Zhang, Xiaoshuai; Yang, Qianru; Wang, Yulong; Ge, Jing; Hammock, Bruce D; Zhang, Cunzheng; Liu, Xianjin

    2018-01-31

    Cry toxins have been widely used in genetically modified organisms for pest control, raising public concern regarding their effects on the natural environment and food safety. In this work, a phage-mediated competitive chemiluminescent immunoassay (c-CLIA) was developed for determination of Cry1Ab toxin using anti-idiotypic camel nanobodies. By extracting RNA from camels' peripheral blood lymphocytes, a naive phage-displayed nanobody library was established. Using anti-Cry1Ab toxin monoclonal antibodies (mAbs) against the library for anti-idiotypic antibody screening, four anti-idiotypic nanobodies were selected and confirmed to be specific for anti-Cry1Ab mAb binding. Thereafter, a c-CLIA was developed for detection of Cry1Ab toxin based on anti-idiotypic camel nanobodies and employed for sample testing. The results revealed a half-inhibition concentration of developed assay to be 42.68 ± 2.54 ng/mL, in the linear range of 10.49-307.1 ng/mL. The established method is highly specific for Cry1Ab recognition, with negligible cross-reactivity for other Cry toxins. For spiked cereal samples, the recoveries of Cry1Ab toxin ranged from 77.4% to 127%, with coefficient of variation of less than 9%. This study demonstrated that the competitive format based on phage-displayed anti-idiotypic nanobodies can provide an alternative strategy for Cry toxin detection.

  11. Antibodies to Pseudogymnoascus destructans are not sufficient for protection against white-nose syndrome

    Science.gov (United States)

    Johnson, Joseph S; Reeder, DeeAnn M; Lilley, Thomas M; Czirják, Gábor Á; Voigt, Christian C; McMichael, James W; Meierhofer, Melissa B; Seery, Christopher W; Lumadue, Shayne S; Altmann, Alexander J; Toro, Michael O; Field, Kenneth A

    2015-01-01

    White-nose syndrome (WNS) is a fungal disease caused by Pseudogymnoascus destructans (Pd) that affects bats during hibernation. Although millions of bats have died from WNS in North America, mass mortality has not been observed among European bats infected by the fungus, leading to the suggestion that bats in Europe are immune. We tested the hypothesis that an antibody-mediated immune response can provide protection against WNS by quantifying antibodies reactive to Pd in blood samples from seven species of free-ranging bats in North America and two free-ranging species in Europe. We also quantified antibodies in blood samples from little brown myotis (Myotis lucifugus) that were part of a captive colony that we injected with live Pd spores mixed with adjuvant, as well as individuals surviving a captive Pd infection trial. Seroprevalence of antibodies against Pd, as well as antibody titers, was greater among little brown myotis than among four other species of cave-hibernating bats in North America, including species with markedly lower WNS mortality rates. Among little brown myotis, the greatest titers occurred in populations occupying regions with longer histories of WNS, where bats lacked secondary symptoms of WNS. We detected antibodies cross-reactive with Pd among little brown myotis naïve to the fungus. We observed high titers among captive little brown myotis injected with Pd. We did not detect antibodies against Pd in Pd-infected European bats during winter, and titers during the active season were lower than among little brown myotis. These results show that antibody-mediated immunity cannot explain survival of European bats infected with Pd and that little brown myotis respond differently to Pd than species with higher WNS survival rates. Although it appears that some species of bats in North America may be developing resistance to WNS, an antibody-mediated immune response does not provide an explanation for these remnant populations. PMID:26078857

  12. Aphid performance changes with plant defense mediated by Cucumber mosaic virus titer.

    Science.gov (United States)

    Shi, Xiaobin; Gao, Yang; Yan, Shuo; Tang, Xin; Zhou, Xuguo; Zhang, Deyong; Liu, Yong

    2016-04-22

    Cucumber mosaic virus (CMV) causes appreciable losses in vegetables, ornamentals and agricultural crops. The green peach aphid, Myzus persicae Sulzer (Aphididae) is one of the most efficient vectors for CMV. The transmission ecology of aphid-vectored CMV has been well investigated. However, the detailed description of the dynamic change in the plant-CMV-aphid interaction associated with plant defense and virus epidemics is not well known. In this report, we investigated the relationship of virus titer with plant defense of salicylic acid (SA) and jasmonic acid (JA) during the different infection time and their interaction with aphids in CMV-infected tobacco plants. Our results showed that aphid performance changed with virus titer and plant defense on CMV-inoculated plants. At first, plant defense was low and aphid number increased gradually. The plant defense of SA signaling pathway was induced when virus titer was at a high level, and aphid performance was correspondingly reduced. Additionally, the winged aphids were increased. Our results showed that aphid performance was reduced due to the induced plant defense mediated by Cucumber mosaic virus titer. Additionally, some wingless aphids became to winged aphids. In this way CMV could be transmitted with the migration of winged aphids. We should take measures to prevent aphids in the early stage of their occurrence in the field to prevent virus outbreak.

  13. Application of the polymerase chain reaction in determination of recombinant retrovirus titers as fifty percent endpoints

    DEFF Research Database (Denmark)

    Husemoen, L L; Gram, G J; Hansen, J E

    2000-01-01

    Retroviral vectors constitute the most efficient system to deliver and integrate foreign genes into mammalian cells. One of the most laborious routine assays in the application of retroviral-mediated gene transfer is the determination of viral titers of vector producer cell lines. Traditionally, ...

  14. Toxoplasmosis Titers and past Suicide Attempts Among Older Adolescents Initiating SSRI Treatment.

    Science.gov (United States)

    Coryell, William; Yolken, Robert; Butcher, Brandon; Burns, Trudy; Dindo, Lilian; Schlechte, Janet; Calarge, Chadi

    2016-01-01

    Latent infection with toxoplasmosis is a prevalent condition that has been linked in animal studies to high-risk behaviors, and in humans, to suicide and suicide attempts. This analysis investigated a relationship between suicide attempt history and toxoplasmosis titers in a group of older adolescents who had recently begun treatment with an SSRI. Of 108 participants, 17 (15.7 %) had a lifetime history of at least one suicide attempt. All were given structured and unstructured diagnostic interviews and provided blood samples. Two individuals (11.9%) with a past suicide attempt, and two (2.1%) without this history, had toxoplasmosis titers ≥ 10 IU/ml (p = 0.166). Those with a past suicide attempt had mean toxoplasmosis titers that were significantly different (p = 0.018) from those of patients who lacked this history. An ROC analysis suggested a lower optimal threshold for distinguishing patients with and without suicide attempts (3.6 IU/ml) than that customarily used to identify seropositivity. Toxoplasmosis titers may quantify a proneness to suicidal behavior in younger individuals being treated with antidepressants.

  15. Mechanism of reduction in titers from lentivirus vectors carrying large inserts in the 3'LTR.

    Science.gov (United States)

    Urbinati, Fabrizia; Arumugam, Paritha; Higashimoto, Tomoyasu; Perumbeti, Anil; Mitts, Kyle; Xia, Ping; Malik, Punam

    2009-09-01

    Self-inactivating (SIN) lentiviruses flanked by the 1.2-kb chicken hypersensitive site-4 (cHS4) insulator element provide consistent, improved expression of transgenes, but have significantly lower titers. The mechanism by which this occurs is unknown. Lengthening the lentiviral (LV) vector transgene cassette by an additional 1.2 kb by an internal cassette caused no further reduction in titers. However, when cHS4 sequences or inert DNA spacers of increasing size were placed in the 3'-long terminal repeat (LTR), infectious titers decreased proportional to the length of the insert. The stage of vector life cycle affected by vectors carrying the large cHS4 3'LTR insert was compared to a control vector: there was no increase in read-through transcription with insertion of the 1.2-kb cHS4 in the 3'LTR. Equal amount of full-length viral mRNA was produced in packaging cells and viral assembly/packaging was unaffected, resulting in comparable amounts of intact vector particles produced by either vectors. However, LV vectors carrying cHS4 in the 3'LTR were inefficiently processed following target-cell entry, with reduced reverse transcription and integration efficiency, and hence lower transduction titers. Therefore, vectors with large insertions in the 3'LTR are transcribed and packaged efficiently, but the LTR insert hinders viral-RNA (vRNA) processing and transduction of target cells. These studies have important implications in design of integrating vectors.

  16. Serological study for antibodies to toxoplasma gondii in Jakarta, Indonesia.

    Science.gov (United States)

    Gandahusada, S

    1978-09-01

    A total of 280 sera from medical students, laboratory personnel from the University of Indonesia and other persons living in Jakarta were tested for antibodies to Toxoplasma gondii by the indirect hemagglutination test. Antibody titers equal to or greater than 1:256 were considered positive and were detected in 35 or 12.5% of the persons tested. The sero-positivity rates were not significant between 178 males (13.5%) and 102 females (10.8%) but were significantly different between persons of Indonesian ancestry (14.3%) and those of Chinese ancestry (2.3%). No correlation could be found between ownership of domestic cats and eating habits and positive titers.

  17. Technical note: Protozoa-specific antibodies raised in sheep plasma bind to their target protozoa in the rumen.

    Science.gov (United States)

    Williams, Y J; Rea, S M; Popovski, S; Skillman, L C; Wright, A-D G

    2014-12-01

    Binding of IgG antibodies to Entodinium spp. in the rumen of sheep (Ovis aries) was investigated by adding IgG, purified from plasma, directly into the rumen. Plasma IgG was sourced from sheep that had or had not been immunized with a vaccine containing whole fixed Entodinium spp. cells. Ruminal fluid was sampled approximately 2 h after each antibody dosing. Binding of protozoa by a specific antibody was detected using an indirect fluorescent antibody test. An antibody titer in the ruminal fluid was determined by ELISA, and the concentration of ruminal fluid ammonia-N and ruminal pH were also determined. Entodinium spp. and total protozoa from IgG-infused sheep were enumerated by microscopic counts. Two-hourly additions of IgG maintained a low antibody titer in the rumen for 12 h and the binding of the antibody to the rumen protozoa was demonstrated. Increased ammonia-N concentrations and altered ruminal fluid pH patterns indicated that additional fermentation of protein was occurring in the rumen after addition of IgG. No reduction in numbers of Entodinium spp. was observed (P>0.05). Although binding of antibodies to protozoa has been demonstrated in the rumen, it is unclear how much cell death occurred. On the balance of probability, it would appear that the antibody was degraded or partially degraded, and the impact of this on protozoal populations and the measurement of a specific titer is also unclear.

  18. Specificity of antibodies from human sera for Naegleria species.

    OpenAIRE

    Marciano-Cabral, F; Cline, M L; Bradley, S G

    1987-01-01

    Serum samples from adult humans in North Carolina and Pennsylvania were assayed for antibodies against four Naegleria species: N. australiensis, N. fowleri, N. gruberi, and N. lovaniensis. Agglutinating activities of serum samples from North Carolina subjects were higher for N. fowleri than were those from Pennsylvania subjects. The distributions of agglutination titers of human serum samples for N. australiensis, N. gruberi, and N. lovaniensis were heterogeneous. The agglutination capabiliti...

  19. Mycofix ameliorative effect on Newcastle disease antibody production in broiler chickens during aflatoxicosis

    Directory of Open Access Journals (Sweden)

    M. T. Gargees

    2008-01-01

    Full Text Available Three experiments were conducted to elucidate the alleviation effects of Mycofix plus 3.0 on Newcastle antibody formation during aflatoxicosis in broiler chickens. Three levels of Mycofix (0.05%, 0.15%, and 0.25% and aflatoxin (2.5ppm, 3.5ppm, and 5ppm were used. Chickens were vaccinated at 8 and 18 days of age. Enzyme-linked immunosorbent assay and Haemagglutination inhibition tests were employed for determination Newcastle antibody titers at 28 days. The results showed that, Mycofix , and only at its high level of addition (0.25% was effective in ameliorating the negative effect of aflatoxin at the rates 2.5ppm and 3.5 ppm levels of inclusion on antibody production but not at the high level of 5ppm on antibody production, comparing with titers in control groups.

  20. Hemolytic anemia caused by chemicals and toxins

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/000590.htm Hemolytic anemia caused by chemicals and toxins To use the sharing features on this page, please enable JavaScript. Hemolytic anemia caused by chemicals and toxins is a lack ...

  1. (AJST) DETECTION AND QUANTIFICATION OF TOXINS IN ...

    African Journals Online (AJOL)

    -, hepato- and neuro-toxins ..... risk assessment of cyanobacterial toxins. In: Hester,. R.E. and Harrison, R.M. (Eds.) Agricultural chemicals and the environment. Issues in Environmental. Science and Technology 5. The Royal Society of.

  2. Toxin synergism in snake venoms

    DEFF Research Database (Denmark)

    Laustsen, Andreas Hougaard

    2016-01-01

    Synergism between venom toxins exists for a range of snake species. Synergism can be derived from both intermolecular interactions and supramolecular interactions between venom components, and can be the result of toxins targeting the same protein, biochemical pathway or physiological process. Few...... simple systematic tools and methods for determining the presence of synergism exist, but include co-administration of venom components and assessment of Accumulated Toxicity Scores. A better understanding of how to investigate synergism in snake venoms may help unravel strategies for developing novel...

  3. Rapid Detection of Escherichia coli O157 and Shiga Toxins by Lateral Flow Immunoassays

    Directory of Open Access Journals (Sweden)

    Jinliang Wang

    2016-03-01

    Full Text Available Shiga toxin-producing Escherichia coli O157:H7 (STEC cause food-borne illness that may be fatal. STEC strains enumerate two types of potent Shiga toxins (Stx1 and Stx2 that are responsible for causing diseases. It is important to detect the E. coli O157 and Shiga toxins in food to prevent outbreak of diseases. We describe the development of two multi-analyte antibody-based lateral flow immunoassays (LFIA; one for the detection of Stx1 and Stx2 and one for the detection of E. coli O157 that may be used simultaneously to detect pathogenic E. coli O157:H7. The LFIA strips were developed by conjugating nano colloidal gold particles with monoclonal antibodies against Stx1 and Stx2 and anti-lipid A antibodies to capture Shiga toxins and O157 antigen, respectively. Our results indicate that the LFIA for Stx is highly specific and detected Stx1 and Stx2 within three hours of induction of STEC with ciprofloxacin at 37 °C. The limit of detection for E. coli O157 LFIA was found to be 105 CFU/mL in ground beef spiked with the pathogen. The LFIAs are rapid, accurate and easy to use and do not require sophisticated equipment or trained personnel. Following the assay, colored bands on the membrane develop for end-point detection. The LFIAs may be used for screening STEC in food and the environment.

  4. Rapid Detection of Escherichia coli O157 and Shiga Toxins by Lateral Flow Immunoassays.

    Science.gov (United States)

    Wang, Jinliang; Katani, Robab; Li, Lingling; Hegde, Narasimha; Roberts, Elisabeth L; Kapur, Vivek; DebRoy, Chitrita

    2016-03-25

    Shiga toxin-producing Escherichia coli O157:H7 (STEC) cause food-borne illness that may be fatal. STEC strains enumerate two types of potent Shiga toxins (Stx1 and Stx2) that are responsible for causing diseases. It is important to detect the E. coli O157 and Shiga toxins in food to prevent outbreak of diseases. We describe the development of two multi-analyte antibody-based lateral flow immunoassays (LFIA); one for the detection of Stx1 and Stx2 and one for the detection of E. coli O157 that may be used simultaneously to detect pathogenic E. coli O157:H7. The LFIA strips were developed by conjugating nano colloidal gold particles with monoclonal antibodies against Stx1 and Stx2 and anti-lipid A antibodies to capture Shiga toxins and O157 antigen, respectively. Our results indicate that the LFIA for Stx is highly specific and detected Stx1 and Stx2 within three hours of induction of STEC with ciprofloxacin at 37 °C. The limit of detection for E. coli O157 LFIA was found to be 10⁵ CFU/mL in ground beef spiked with the pathogen. The LFIAs are rapid, accurate and easy to use and do not require sophisticated equipment or trained personnel. Following the assay, colored bands on the membrane develop for end-point detection. The LFIAs may be used for screening STEC in food and the environment.

  5. [Analysis of Correlation between IgG Titer of Pregnant Women and Neonatal Hemolytic Complications of Different Blood Groups].

    Science.gov (United States)

    Ye, Hai-Hui; Huang, Hong-Hai; Wang, Xiao-Lin; Pi, You-Jun

    2017-10-01

    To study the relationship between IgG titer of pregnant women and hemolytic disease of newborn(HDN) with different blood groups. Four hundred pregnant women, including pregnant women with type O blood, were selected from May 2014 to January 2015 in our hospital for inspection and a couple of different blood groups, the IgG titer of pregnant women were detected in the inspection process. According to neonatal HDN, newborns were divided into 2 groups: HDN group(85 cases) and non-HDN group(315 cases). The incidence of postpartum neonatal hemolytic disease was tracked and the correlation of IgG titers with HDN were systematically analyzed. In the production and inspection process, the IgG titer in pregnant women was divided into groups. the comparison of HDN incidence rate in 4 groups of IgG titer >64 and IgG titer group showed that the prevalence of ABO hemolytic disease of newborn were 96.9%, 79.6%, 63, 7% and 28.8%, there was a certain correlation of pregnant women IgG titers with ABO hemolytic disease of the newborn, that is, with the increase of IgG titer, the incidence of hemolytic disease of newborns increased in certain degree (r=0.8832), the risk in 4 groups of neonatal HDN was higher than that in IgG titer 64 HDN group. There is a certain corelation between prevalence of ABO-HDN and IgG titer of pregnant women. For these pregnant women, the control of the pregnant women IgG titer has a positive clinical significance to reduce the incidence of hemolytic disease of the newborn.

  6. Inhibition of cholera toxin and other AB toxins by polyphenolic compounds

    Science.gov (United States)

    All AB-type protein toxins have intracellular targets despite an initial extracellular location. These toxins use different methods to reach the cytosol and have different effects on the target cell. Broad-spectrum inhibitors against AB toxins are therefore hard to develop because the toxins use dif...

  7. Toxin yet not toxic: Botulinum toxin in dentistry

    Directory of Open Access Journals (Sweden)

    Archana M.S.

    2016-04-01

    Full Text Available Paracelsus contrasted poisons from nonpoisons, stating that “All things are poisons, and there is nothing that is harmless; the dose alone decides that something is a poison”. Living organisms, such as plants, animals, and microorganisms, constitute a huge source of pharmaceutically useful medicines and toxins. Depending on their source, toxins can be categorized as phytotoxins, mycotoxins, or zootoxins, which include venoms and bacterial toxins. Any toxin can be harmful or beneficial. Within the last 100 years, the perception of botulinum neurotoxin (BTX has evolved from that of a poison to a versatile clinical agent with various uses. BTX plays a key role in the management of many orofacial and dental disorders. Its indications are rapidly expanding, with ongoing trials for further applications. However, despite its clinical use, what BTX specifically does in each condition is still not clear. The main aim of this review is to describe some of the unclear aspects of this potentially useful agent, with a focus on the current research in dentistry.

  8. Elisa evaluation of the levels of antibodies against Infectious Bronchitis Virus in laying hens using egg yolk as substrate

    Directory of Open Access Journals (Sweden)

    RH Rauber

    2004-06-01

    Full Text Available The present work was carried out to compare Infectious Bronchitis Virus (IBV antibody titers in serum and egg yolk samples from laying hens. Sixty paired blood and egg samples were collected from laying hens of two farms. Serum samples were frozen, while egg yolk samples were diluted (1:500 before freezing. Serum and yolk samples were tested for the presence of IBV antibodies by indirect ELISA (commercial kit and titers were compared by a correlation test (alpha=0.05. There was a high correlation (r=0.62 between the two kinds of samples, which means that titers of IBV antibodies in the egg yolk and in serum samples are quite the same. Considering that blood collection causes deep stress that leads to economic losses, and since eggs are collected daily on the farm, results reported here are of importance to poultry production.

  9. Influence of long-term treatment with tetracycline and niacinamide on antibody production in dogs with discoid lupus erythematosus.

    Science.gov (United States)

    Mueller, Ralf S; Fieseler, Kathryn V; Bettenay, Sonya V; Rosychuk, Rodney A W

    2002-04-01

    To evaluate the effect of long-term treatment with tetracycline and niacinamide on antibody production in dogs by measuring postvaccinal serum concentrations of antibodies against canine parvovirus and canine distemper virus. 10 dogs receiving long-term treatment with tetracycline and niacinamide (treatment group) and 10 healthy dogs (control group). The treatment group included 9 dogs with discoid lupus erythematosus and 1 dog with pemphigus foliaceus on long-term treatment (> 12 months) with tetracycline and niacinamide. The control group included 10 healthy dogs with no clinical signs of disease and no administered medications for the past 3 months. Blood samples were obtained from all dogs by jugular venipuncture. Serum antibody titers against canine parvovirus and canine distemper virus antigens were measured, using hemaglutination inhibition and serum neutralization, respectively, and compared between groups. A significant difference in antibody titers between treatment- and control-group dogs was not found. All dogs had protective antibody titers against canine distemper virus, and 8 of 10 dogs from each group had protective titers against canine parvovirus infection. These results provide evidence that long-term treatment with tetracycline and niacinamide does not interfere with routine vaccinations and thus does not seem to influence antibody production in dogs.

  10. Tetanus Neurotoxin Neutralizing Antibodies Screened from a Human Immune scFv Antibody Phage Display Library

    Directory of Open Access Journals (Sweden)

    Han Wang

    2016-09-01

    Full Text Available Tetanus neurotoxin (TeNT produced by Clostridium tetani is one of the most poisonous protein substances. Neutralizing antibodies against TeNT can effectively prevent and cure toxicosis. Using purified Hc fragments of TeNT (TeNT-Hc as an antigen, three specific neutralizing antibody clones recognizing different epitopes were selected from a human immune scFv antibody phage display library. The three antibodies (2-7G, 2-2D, and S-4-7H can effectively inhibit the binding between TeNT-Hc and differentiated PC-12 cells in vitro. Moreover, 2-7G inhibited TeNT-Hc binding to the receptor via carbohydrate-binding sites of the W pocket while 2-2D and S-4-7H inhibited binding of the R pocket. Although no single mAb completely protected mice from the toxin, they could both prolong survival when challenged with 20 LD50s (50% of the lethal dose of TeNT. When used together, the mAbs completely neutralized 1000 LD50s/mg Ab, indicating their high neutralizing potency in vivo. Antibodies recognizing different carbohydrate-binding pockets could have higher synergistic toxin neutralization activities than those that recognize the same pockets. These results could lead to further production of neutralizing antibody drugs against TeNT and indicate that using TeNT-Hc as an antigen for screening human antibodies for TeNT intoxication therapy from human immune antibody library was convenient and effective.

  11. Increased TRAb and/or low anti-TPO titers at diagnosis of graves' disease are associated with an increased risk of developing ophthalmopathy after onset.

    Science.gov (United States)

    Lantz, M; Planck, T; Asman, P; Hallengren, B

    2014-02-01

    Patients with low thyroid peroxidase antibodies (anti-TPO) and increased TSH-receptor antibodies (TRAb) at diagnosis of Graves' disease (GD) have been suggested to have an increased risk to develop Graves' ophthalmopathy (GO). The aim was to evaluate if GO development can be predicted.This is an observational study with registration of possible GD and GO risk factors.399 patients with GD were registered 2003-2008 in Malmö, Sweden and out of these 310 were retrospectively followed up to 6 years. The main outcome measures were anti-TPO titer, TRAb titer, smoking habits, radioiodine treatment and GO development.TRAb was assessed with a third generation assay at GD diagnosis in 231 patients. The proportion of patients with GO increased above the median 6.3 IU/L both at diagnosis of GD (p=0.001) and at follow-up (p=0.0001).The distribution of GO patients anti-TPO above or below 20 kIU/L at diagnosis of GD was similar between groups (p=0.239). However at follow-up anti-TPOTPO>20 kIU/L (p=0.018).87% of patients who developed GO after GD diagnosis had TRAb above 6.3 IU/L and/or anti-TPO below 20 kIU/L. The proportion of GO was doubled in GD patients treated with radioiodine but could not explain the described findingsAnti-TPO6.3 IE/L at the time of GD diagnosis were associated with an increased risk to develop GO after diagnosis of GD. © J. A. Barth Verlag in Georg Thieme Verlag KG Stuttgart · New York.

  12. Age Dependence and Isotype Specificity of Influenza Virus Hemagglutinin Stalk-Reactive Antibodies in Humans.

    Science.gov (United States)

    Nachbagauer, Raffael; Choi, Angela; Izikson, Ruvim; Cox, Manon M; Palese, Peter; Krammer, Florian

    2016-01-19

    Influenza remains a major global health burden. Seasonal vaccines offer protection but can be rendered less effective when the virus undergoes extensive antigenic drift. Antibodies that target the highly conserved hemagglutinin stalk can protect against drifted viruses, and vaccine constructs designed to induce such antibodies form the basis for a universal influenza virus vaccine approach. In this study, we analyzed baseline and postvaccination serum samples of children (6 to 59 months), adults (18 to 49 years), and elderly individuals (≥65 years) who participated in clinical trials with a recombinant hemagglutinin-based vaccine. We found that baseline IgG and IgA antibodies against the H1 stalk domain correlated with the ages of patients. Children generally had very low baseline titers and did not respond well to the vaccine in terms of making stalk-specific antibodies. Adults showed the highest induction of stalk-specific antibodies, but the elderly had the highest absolute antibody titers against the stalk. Importantly, the stalk antibodies measured by enzyme-linked immunosorbent assay (ELISA) showed neutralizing activity in neutralization assays and protected mice in a passive-transfer model in a stalk titer-dependent manner. Finally, we found similar patterns of stalk-specific antibodies directed against the H3 and influenza B virus hemagglutinins, albeit at lower levels than those measured against the H1 stalk. The relatively high levels of stalk-specific antibodies in the elderly patients may explain the previously reported low influenza virus infection rates in this age group. (This study has been registered at ClinicalTrials.gov under registration no. NCT00336453, NCT00539981, and NCT00395174.) The present study provides evidence that titers of broadly neutralizing hemagglutinin stalk-reactive antibodies increase with age, possibly due to repeated exposure to divergent influenza viruses. These relatively high levels of antistalk titers may be

  13. Mutagenic Deimmunization of Diphtheria Toxin for Use in Biologic Drug Development

    Directory of Open Access Journals (Sweden)

    Joerg U. Schmohl

    2015-10-01

    Full Text Available Background: Targeted toxins require multiple treatments and therefore must be deimmunized. We report a method of protein deimmunization based on the point mutation of highly hydrophilic R, K, D, E, and Q amino acids on the molecular surface of truncated diphtheria-toxin (DT390. Methods: Based on their surface position derived from an X-ray-crystallographic model, residues were chosen for point mutation that were located in prominent positions on the molecular surface and away from the catalytic site. Mice were immunized with a targeted toxin containing either a mutated DT390 containing seven critical point mutations or the non-mutated parental toxin form. Results: Serum analysis revealed a significant 90% reduction in anti-toxin antibodies in mice immunized with the mutant, but not the parental drug form despite multiple immunizations. The experiment was repeated in a second strain of mice with a different MHC-haplotype to address whether point mutation removed T or B cell epitopes. Findings were identical indicating that B cell epitopes were eliminated from DT. The mutant drug form lost only minimal activity in vitro as well as in vivo. Conclusion: These findings indicate that this method may be effective for deimmunizing of other proteins and that discovery of a deimmunized form of DT may lead to the development of more effective targeted toxin.

  14. Development of Polyclonal Antibody against Clenbuterol for Immunoassay Application

    Directory of Open Access Journals (Sweden)

    Nurul Ain A. Talib

    2018-03-01

    Full Text Available Development of an immunoassay for clenbuterol (CLB detection required an anti-CLB antibody as an important bioreceptor. In this study, we report our work on production and purification of a rabbit-derived polyclonal anti-CLB antibody. The antibody was then purified by nProtein A Sepharose affinity column and the antibody purity was confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE analysis. The activities of purified antibody were evaluated based on high antibody titer determined from enzyme-linked immunosorbent assay (ELISA. The sensitivity and selectivity of this antibody was evaluated and exhibits negligible cross-reactivity to antibiotics other than β-agonist families. Evaluation of the antibody as bioreceptor in immunoassay was performed using direct competitive ELISA and exhibited linear calibration plot (R2 = 0.9484. The antibody was used to detect the content of CLB in spiked milk samples and the recovery of more than 92% indicating significant performance as bioreceptor for the development of a rapid and simple immunoassay.

  15. Case study on human α1-antitrypsin: Recombinant protein titers obtained by commercial ELISA kits are inaccurate

    DEFF Research Database (Denmark)

    Hansen, Henning Gram; Kildegaard, Helene Faustrup; Min Lee, Gyun

    2016-01-01

    Accurate titer determination of recombinant proteins is crucial for evaluating protein production cell lines and processes. Even though enzyme-linked immunosorbent assay (ELISA) is the most widely used assay for determining protein titer, little is known about the accuracy of commercially availab...

  16. Thyroid failure in the elderly: microsomal antibodies as discriminant for therapy

    Energy Technology Data Exchange (ETDEWEB)

    Rosenthal, M.J.; Hunt, W.C.; Garry, P.J.; Goodwin, J.S.

    1987-07-10

    Thyrotropin (thyroid-stimulating hormone (TSH)) levels were elevated above 4.0 mU/L (..mu..U/mL) in serum samples from 13.2% of 258 healthy elderly subjects. To investigate the natural history of progressive thyroid failure, serial thyroid functions were measured using radioimmunoassay for four years in 26 of these subjects with elevated TSH levels. In one third of these subjects, biochemical thyroid failure developed within the course of the study. All subjects with initial TSH levels above 20 mU/L (..mu..U/mL), and 80% of those with high-titer thyroid antimicrosomal antibodies (regardless of initial TSH level), became overtly hypothyroid. Compared with subjects with high-titer antibody, those with antibody titer less than 1:1600 had lower TSH and higher thyroxine levels, and thyroid failure developed in none during the study. These results suggest that among older patients with isolated elevations of the TSH level, only those with markedly elevated TSH levels or high-titer antimicrosomal antibodies should be prophylactically treated with levothyroxine sodium replacement.

  17. Antibody response in cattle after vaccination with inactivated and attenuated rabies vaccines

    Directory of Open Access Journals (Sweden)

    RODRIGUES da SILVA Andréa de Cássia

    2000-01-01

    Full Text Available Despite the absence of current official reports showing the number of cattle infected by rabies, it is estimated that nearly 30,000 bovines are lost each year in Brazil. In order to minimize the important economic losses, control of the disease is achieved by eliminating bat colonies and by herd vaccination. In this study, we compare the antibody response in cattle elicited by vaccination with an attenuated ERA vaccine (AEvac and an inactivated-adjuvanted PV (IPVvac vaccine. The antibody titers were appraised by cell-culture neutralization test and ELISA, and the percentage of seropositivity was ascertained for a period of 180 days. IPVvac elicited complete seropositivity rates from day 30 to day 150, and even on day 180, 87% of the sera showed virus-neutralizing antibody titers (VNA higher than 0.5IU/ml. There were no significant differences between the VNA titers and seropositivity rates obtained with IPVvac in the two methods tested. AEvac, however, elicited significantly lower titers than those observed in the group receiving inactivated vaccine. In addition, the profiles of antirabies IgG antibodies, evaluated by ELISA, and VNA, appraised by cell-culture neutralization test, were slightly different, when both vaccines were compared.

  18. Clinical relevance of different IgG and IgM serum antibody responses to Borrelia burgdorferi after antibiotic therapy for erythema migrans: long-term follow-up study of 113 patients.

    Science.gov (United States)

    Glatz, Martin; Golestani, Marjaneh; Kerl, Helmut; Müllegger, Robert R

    2006-07-01

    To investigate the kinetics of anti-Borrelia burgdorferi antibodies for a minimum of 1 year after antibiotic therapy in patients with erythema migrans (EM) and to correlate antibody titer kinetics with clinical variables. Retrospective study of serial anti-B burgdorferi antibodies in correlation to clinical variables. University-based hospital. One hundred thirteen patients with EM. Pretreatment and a median of 4 consecutive posttreatment serum samples from median follow-up of more than 400 days were simultaneously investigated for anti-B burgdorferi IgG and IgM antibodies. Semiquantitative titers were plotted to identify different groups of antibody kinetics. Individual patients were then stratified to those groups according to their antibody development. A statistical comparison of clinical and therapy-related characteristics among the serologic groups was performed. Anti-B burgdorferi IgG and IgM antibody titers developed in 3 distinct courses: persistent positivity across follow-up (IgG: 12 patients, 11%; IgM: 14, 12%), persistent negativity (IgG: 63, 56%; IgM: 47, 42%), and decrease of a positive pretreatment titer to a negative titer approximately 5 months after therapy (IgG: 34, 30%; IgM: 49, 43%). Statistics revealed significant correlations only between persistent positive IgG titers and long disease duration or large EM lesions before therapy. Long duration or large size of EM before therapy correlates with persistence of a positive anti- B burgdorferi IgG antibody titer after therapy. Serologic profiles do not depend on the type or duration of therapy or the clinical course thereafter. Thus, antibody testing in the follow-up of patients with EM is inappropriate for the assessment of therapeutic response.

  19. Shigella Sonnei and Shiga Toxin

    Centers for Disease Control (CDC) Podcasts

    2016-07-28

    Katherine Lamba, an infectious disease epidemiologist with the California Department of Public Health, discusses Shiga Toxin producing Shigella sonnei.  Created: 7/28/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 7/28/2016.

  20. Risk Assessment of Shellfish Toxins

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    Rex Munday

    2013-11-01

    Full Text Available Complex secondary metabolites, some of which are highly toxic to mammals, are produced by many marine organisms. Some of these organisms are important food sources for marine animals and, when ingested, the toxins that they produce may be absorbed and stored in the tissues of the predators, which then become toxic to animals higher up the food chain. This is a particular problem with shellfish, and many cases of poisoning are reported in shellfish consumers each year. At present, there is no practicable means of preventing uptake of the toxins by shellfish or of removing them after harvesting. Assessment of the risk posed by such toxins is therefore required in order to determine levels that are unlikely to cause adverse effects in humans and to permit the establishment of regulatory limits in shellfish for human consumption. In the present review, the basic principles of risk assessment are described, and the progress made toward robust risk assessment of seafood toxins is discussed. While good progress has been made, it is clear that further toxicological studies are required before this goal is fully achieved.

  1. Different Assay Conditions for Detecting the Production and Release of Heat-Labile and Heat-Stable Toxins in Enterotoxigenic Escherichia coli Isolates

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    Letícia B. Rocha

    2013-12-01

    Full Text Available Enterotoxigenic Escherichia coli (ETEC produce heat-labile (LT and/or heat-stable enterotoxins (ST. Despite that, the mechanism of action of both toxins are well known, there is great controversy in the literature concerning the in vitro production and release of LT and, for ST, no major concerns have been discussed. Furthermore, the majority of published papers describe the use of only one or a few ETEC isolates to define the production and release of these toxins, which hinders the detection of ETEC by phenotypic approaches. Thus, the present study was undertaken to obtain a better understanding of ST and LT toxin production and release under laboratory conditions. Accordingly, a collection of 90 LT-, ST-, and ST/LT-producing ETEC isolates was used to determine a protocol for toxin production and release aimed at ETEC detection. For this, we used previously raised anti-LT antibodies and the anti-ST monoclonal and polyclonal antibodies described herein. The presence of bile salts and the use of certain antibiotics improved ETEC toxin production/release. Triton X-100, as chemical treatment, proved to be an alternative method for toxin release. Consequently, a common protocol that can increase the production and release of LT and ST toxins could facilitate and enhance the sensitivity of diagnostic tests for ETEC using the raised and described antibodies in the present work.

  2. Identification and validation of a linear protective neutralizing epitope in the β-pore domain of alpha toxin.

    Science.gov (United States)

    Oscherwitz, Jon; Cease, Kemp B

    2015-01-01

    The plethora of virulence factors associated with Staphylococcus aureus make this bacterium an attractive candidate for a molecularly-designed epitope-focused vaccine. This approach, which necessitates the identification of neutralizing epitopes for incorporation into a vaccine construct, is being evaluated for pathogens where conventional approaches have failed to elicit protective humoral responses, like HIV-1 and malaria, but may also hold promise for pathogens like S. aureus, where the elicitation of humoral immunity against multiple virulence factors may be required for development of an effective vaccine. Among the virulence factors employed by S. aureus, animal model and epidemiological data suggest that alpha toxin, a multimeric β-pore forming toxin like protective antigen from Bacillus anthracis, is particularly critical, yet no candidate neutralizing epitopes have been delineated in alpha toxin to date. We have previously shown that a linear determinant in the 2β2-2β3 loop of the pore forming domain of B. anthracis protective antigen is a linear neutralizing epitope. Antibody against this site is highly potent for neutralizing anthrax lethal toxin in vitro and for protection of rabbits in vivo from virulent B. anthracis. We hypothesized that sequences in the β-pore of S. aureus alpha toxin that share structural and functional homology to β-pore sequences in protective antigen would contain a similarly critical neutralizing epitope. Using an in vivo mapping strategy employing peptide immunogens, an optimized in vitro toxin neutralization assay, and an in vivo dermonecrosis model, we have now confirmed the presence of this epitope in alpha toxin, termed the pore neutralizing determinant. Antibody specific for this determinant neutralizes alpha toxin in vitro, and is highly effective for mitigating dermonecrosis and bacterial growth in a mouse model of S. aureus USA300 skin infection. The delineation of this linear neutralizing determinant in alpha

  3. Identification and validation of a linear protective neutralizing epitope in the β-pore domain of alpha toxin.

    Directory of Open Access Journals (Sweden)

    Jon Oscherwitz

    Full Text Available The plethora of virulence factors associated with Staphylococcus aureus make this bacterium an attractive candidate for a molecularly-designed epitope-focused vaccine. This approach, which necessitates the identification of neutralizing epitopes for incorporation into a vaccine construct, is being evaluated for pathogens where conventional approaches have failed to elicit protective humoral responses, like HIV-1 and malaria, but may also hold promise for pathogens like S. aureus, where the elicitation of humoral immunity against multiple virulence factors may be required for development of an effective vaccine. Among the virulence factors employed by S. aureus, animal model and epidemiological data suggest that alpha toxin, a multimeric β-pore forming toxin like protective antigen from Bacillus anthracis, is particularly critical, yet no candidate neutralizing epitopes have been delineated in alpha toxin to date. We have previously shown that a linear determinant in the 2β2-2β3 loop of the pore forming domain of B. anthracis protective antigen is a linear neutralizing epitope. Antibody against this site is highly potent for neutralizing anthrax lethal toxin in vitro and for protection of rabbits in vivo from virulent B. anthracis. We hypothesized that sequences in the β-pore of S. aureus alpha toxin that share structural and functional homology to β-pore sequences in protective antigen would contain a similarly critical neutralizing epitope. Using an in vivo mapping strategy employing peptide immunogens, an optimized in vitro toxin neutralization assay, and an in vivo dermonecrosis model, we have now confirmed the presence of this epitope in alpha toxin, termed the pore neutralizing determinant. Antibody specific for this determinant neutralizes alpha toxin in vitro, and is highly effective for mitigating dermonecrosis and bacterial growth in a mouse model of S. aureus USA300 skin infection. The delineation of this linear neutralizing

  4. Neutralizing antibody response in the patients with hand, foot and mouth disease to enterovirus 71 and its clinical implications

    Directory of Open Access Journals (Sweden)

    Zhu Liye

    2011-06-01

    Full Text Available Abstract Enterovirus 71 (EV71 has emerged as a significant pathogen causing large outbreaks in China for the past 3 years. Developing an EV71 vaccine is urgently needed to stop the spread of the disease; however, the adaptive immune response of humans to EV71 infection remains unclear. We examined the neutralizing antibody titers in HFMD patients and compared them to those of asymptomatic healthy children and young adults. We found that 80% of HFMD patients became positive for neutralizing antibodies against EV71 (GMT = 24.3 one day after the onset of illness. The antibody titers in the patients peaked two days (GMT = 79.5 after the illness appeared and were comparable to the level of adults (GMT = 45.2. Noticeably, the antibody response was not correlated with disease severity, suggesting that cellular immune response, besides neutralizing antibodies, could play critical role in controlling the outcome of EV71 infection in humans.

  5. O perfil da antiestreptolisina O no diagnóstico da febre reumática aguda Antistreptolysin O titer profile in acute rheumatic fever diagnosis

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    Claudia Saad Magalhães Machado

    2001-04-01

    Full Text Available OBJETIVO: estabelecer o perfil dos títulos de ASO, mediante o diagnóstico diferencial da FRA com outras afecções que também cursam com níveis elevados de ASO. MÉTODOS: foram estudados 78 casos de FRA na apresentação e seguimento, 22 de coréia isolada, 45 de infecções orofaringeanas recorrentes (IOR e 23 de artrites idiopáticas juvenis (AIJ, com início ou reativação recente. A determinação seqüencial de ASO (UI/ml foi realizada por ensaio nefelométrico automatizado (Behring®-Germany nos períodos de 0-7 dias, 1-2 semanas, 2-4 semanas, 1-2 meses, 2-4 meses, 4-6 meses, 6-12 meses, 1-2 anos, 2-3 anos, 3-4 anos e 4-5 anos após o diagnóstico. RESULTADOS: os títulos de ASO na fase aguda da FRA apresentaram elevação significante até o intervalo de 2- 4 meses (p 960 UI/ml. CONCLUSÃO: esta reavaliação do perfil da ASO indicou uma resposta exuberante na fase aguda da febre reumática indicou ainda que os seus níveis séricos podem diferenciá-la de outras afecções que também cursam com níveis elevados de ASO, como as infecções orofaringeanas recorrentes ou as artrites idiopáticas juvenis em atividade.OBJECTIVE: to determine ASO titer profile by establishing ARF differential diagnoses of other diseases with high levels of ASO antibodies. METHODS: we investigated 78 patients with ARF at onset and follow-up, 22 with isolated chorea at onset, 45 with recurrent oropharyngeal tonsillitis, and 23 with recent flare of juvenile idiopathic arthritis. We tested ASO with automated particle-enhanced immunonephelometric assay (Behring®-Germany. The ASO (IU/ml titers were assessed at the following time intervals: 0-7 days, 1-2 weeks, 2-4 weeks, 1-2 months, 2-4 months, 4-6 months, 6-12 months, 1-2 years, 2-3 years, 3-4 years, and 4-5 years after onset of ARF. RESULTS: ASO titers in patients diagnosed with ARF had a significant increase up to the 2-4-month time interval (P < 0.0001. Baseline levels were observed afterwards in patients

  6. Inactivation of allergens and toxins.

    Science.gov (United States)

    Morandini, Piero

    2010-11-30

    Plants are replete with thousands of proteins and small molecules, many of which are species-specific, poisonous or dangerous. Over time humans have learned to avoid dangerous plants or inactivate many toxic components in food plants, but there is still room for ameliorating food crops (and plants in general) in terms of their allergens and toxins content, especially in their edible parts. Inactivation at the genetic rather than physical or chemical level has many advantages and classical genetic approaches have resulted in significant reduction of toxin content. The capacity, offered by genetic engineering, of turning off (inactivating) specific genes has opened up the possibility of altering the plant content in a far more precise manner than previously available. Different levels of intervention (genes coding for toxins/allergens or for enzymes, transporters or regulators involved in their metabolism) are possible and there are several tools for inactivating genes, both direct (using chemical and physical mutagens, insertion of transposons and other genetic elements) and indirect (antisense RNA, RNA interference, microRNA, eventually leading to gene silencing). Each level/strategy has specific advantages and disadvantages (speed, costs, selectivity, stability, reversibility, frequency of desired genotype and regulatory regime). Paradigmatic examples from classical and transgenic approaches are discussed to emphasize the need to revise the present regulatory process. Reducing the content of natural toxins is a trade-off process: the lesser the content of natural toxins, the higher the susceptibility of a plant to pests and therefore the stronger the need to protect plants. As a consequence, more specific pesticides like Bt are needed to substitute for general pesticides. Copyright © 2010 Elsevier B.V. All rights reserved.

  7. Antimeasles antibodies in children submitted to different vaccination schedules

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    Solange Artimos de Oliveira

    1993-06-01

    Full Text Available ln order to study the measles antibody behavior of three vaccination schedules, 684 children were divided into 4 Groups: Group A (341 vaccinated children under the age of one; Group B (101 children at the age of one; Group C (74 children under the age of one and one at the age of one; Group D (163 unvaccinated children with a history of measles in the past - Group control. Children of Group A presented lower rates and 25.9% of the age group under two did not show any measles antibodies. In Group B, all the children presented antibodies. In Group C onby 4.0% did not. In all age groups, the geometric mean HI antibody titers of Group A were lower than the valuesfound in the other groups. The age at vaccination was the factor of greater influence on the results of this study.

  8. Transplantation of ABO A2 kidneys into O recipients: do IgM anti-A1 titers matter?

    Science.gov (United States)

    Tierney, Joshua; Shaffer, David

    2015-04-01

    The ABO blood subgroup A2 expresses lower levels of A antigen on the cell surface and is less immunogenic toward anti-A immunoglobulin present in blood type O or B recipients. Previous studies have shown successful kidney transplantation from A2 donors into O or B recipients with low pre-transplant anti-A titers. Previous studies suggest good results with recipient IgG titers A1 IgM titers on early outcomes following A2 to O or B kidney transplantation. We performed a single center, retrospective review of all A2 to O living donor kidney transplants. All recipients had pre-transplant anti-A IgG titers <1:8. IgM titers were measured in all recipients and were reported but not used to determine eligibility for transplant. From 2001 to 2013, we performed seven consecutive A2 to O living donor kidney transplants. Early allograft dysfunction, acute rejection or thrombotic microangiopathy, occurred in four patients and were associated with high IgM titers despite low IgG titers. Our data show a high incidence of early acute rejection or thrombotic microangiopathy in A2 to O kidney transplants with high recipient anti-A IgM titers despite low IgG titers. Steps to lower anti-IgM pre-transplant may reduce the risk of early allograft dysfunction in A2 to O or B kidney transplants. Attention should be paid to IgM titers in establishing individual center selection criteria for A2 to B kidney transplants under the new UNOS kidney allocation system. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Kinetic and HPV infection effects on cross-type neutralizing antibody and avidity responses induced by Cervarix®

    Science.gov (United States)

    Kemp, Troy J.; Safaeian, Mahboobeh; Hildesheim, Allan; Pan, Yuanji; Penrose, Kerri J.; Porras, Carolina; Schiller, John T.; Lowy, Douglas R.; Herrero, Rolando; Pinto, Ligia A.

    2012-01-01

    Background We previously demonstrated that Cervarix® elicits antibody responses against vaccine-related types for which clinical efficacy was demonstrated (HPV-31 and -45). Here, we evaluated the kinetics of neutralization titers and avidity of Cervarix®-induced antibodies up to 36 months of follow-up in unexposed and HPV infected women. Methods A subset of women who participated in the Cost Rica HPV-16/18 Vaccine Trial had pre- and post-vaccination sera tested for antibody responses to HPV-16, -18, -31, -45, and -58 using a pseudovirion-based neutralization assay, and HPV-16 antibody avidity using an HPV-16 L1 VLP (virus-like particle)-based ELISA developed in our laboratory. Results In uninfected women, neutralizing antibody titers did not reach significance until after the 3rd dose for HPV-31 (month 12, p=0.009) and HPV-45 (month 12, p=0.003), but then persisted up to month 36 (HPV-31, p=0.01; HPV-45, p=0.002). Individuals infected with HPV-16 or HPV-31 at enrollment developed a significantly higher median antibody response to the corresponding HPV type after one dose, but there was not a difference between median titers after three doses compared to the HPV negative group. Median HPV-16 antibody avidity and titer increased over time up to month 12; however, the HPV-16 avidity did not correlate well with HPV-16 neutralizing antibody titers at each time point examined, except for month 6. The median avidity levels were higher in HPV-16 infected women at month 1 (p=0.04) and lower in HPV-16 infected women at month 12 (p=0.006) compared to the HPV negative women. Conclusions The persistence of cross-neutralization titers at month 36 suggests cross-reactive antibody responses are likely to persist long-term and are not influenced by infection status at enrollment. However, the weak correlation between avidity and neutralization titers emphasizes the need for examining avidity in efficacy studies to determine if high avidity antibodies play a critical role in

  10. Randomized Trials Comparing Inactivated Vaccine after Medium- or High-titer Measles Vaccine with Standard Titer Measles Vaccine after Inactivated Vaccine

    DEFF Research Database (Denmark)

    Aaby, Peter; Ravn, Henrik; Benn, Christine S.

    2016-01-01

    Background: Observational studies have suggested that girls have higher mortality if their most recent immunization is an inactivated vaccine rather than a live vaccine. We therefore reanalyzed 5 randomized trials of early measles vaccine (MV) in which it was possible to compare an inactivated......) compared with a standard titer MV (after inactivated vaccine). Girls had a MRR of 1.89 (1.27-2.80), whereas there was no effect for boys, the sex-differential effect being significant (P = 0.02). Excluding measles cases did not alter these conclusions, the MRR after inactivated vaccines (after MTMV or HTMV......) being 1.40 (1.06-1.86) higher overall and 1.92 (1.29-2.86) for girls. Control for variations in national immunization schedules for other vaccines did not modify these results. Conclusions: After 9 months of age, all children had been immunized against measles, and mortality in girls was higher when...

  11. Mechanism of Shiga Toxin Clustering on Membranes

    DEFF Research Database (Denmark)

    Pezeshkian, Weria; Gao, Haifei; Arumugam, Senthil

    2017-01-01

    The bacterial Shiga toxin interacts with its cellular receptor, the glycosphingolipid globotriaosylceramide (Gb3 or CD77), as a first step to entering target cells. Previous studies have shown that toxin molecules cluster on the plasma membrane, despite the apparent lack of direct interactions...... toxin molecules. By contrast, in coarse-grained computer simulations, a correlation was found between clustering and toxin nanoparticle-driven suppression of membrane fluctuations, and experimentally we observed that clustering required the toxin molecules to be tightly bound to the membrane surface....... The most likely interpretation of these findings is that a membrane fluctuation-induced force generates an effective attraction between toxin molecules. Such force would be of similar strength to the electrostatic force at separations around 1 nm, remain strong at distances up to the size of toxin...

  12. Ovaries and regulation of juvenile hormone titer in Acheta domesticus L. (Orthoptera).

    Science.gov (United States)

    Renucci, M; Strambi, C; Strambi, A; Augier, R; Charpin, P

    1990-04-01

    A study was performed on females Acheta domesticus to examine the effects of various experimental conditions on the ovarian physiology. Using a radioimmunoassay to determine juvenile hormone (JH) titers as well as in vitro JH biosynthesis, we observed that retention of mature follicles in egg-retaining females, i.e., virgins or mated females not provided an egg-laying substrate, inhibits JH production and consequently oocyte development. Mating in intact as well as ovariectomized females does not affect corpora allata activity. It is only when mating is associated with egg laying that JH biosynthesis and hemolymph titers increased and oocyte development and fecundity are stimulated. Despite lower JH biosynthesis, ovariectomized females present enlarged corpora allata and the levels of JH observed in their hemolymph were intermediate between those of intact egg-laying and virgin females. In intact females, the hemolymph JH titers as well as the JH esterase activities were related to ovarian development. JH esterase activity was very high in ovariectomized animals. Several factors involved in ovarian development of A. domesticus are discussed.

  13. Autoimmune thyroiditis in antinuclear antibody positive children without rheumatologic disease

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    Arkachaisri Thaschawee

    2010-05-01

    Full Text Available Abstract Background Children are commonly referred to a pediatric rheumatology center for the laboratory finding of an Anti-nuclear antibody (ANA of undetermined significance. Previous studies regarding adult rheumatology patients have supported an association between ANA and anti-thyroid antibodies, with the prevalence of thyroid antibodies being significantly higher in patients referred to a rheumatology center for an ANA without evidence of connective tissue disease compared to the general population. The purpose of the present study was to determine the frequency of thyroid antibodies in children referred to a pediatric rheumatology center for a positive ANA without evidence of a connective tissue disease. Methods A retrospective chart review was performed on children who were referred to our pediatric rheumatology center between August 2003 and March 2007 for positive ANA with concurrent thyroid antibody and thyroid function tests performed who did not fulfill criteria for a specific connective tissue disease. Laboratory and clinical features were recorded and analyzed. Mean and standard deviation were used to describe continuous data. Chi-square or Fisher's exact tests were used to compare proportions between variables. Results One-hundred and four ANA-positive patients with concurrent thyroid studies were evaluated (88% female, 93% Caucasian, mean age 11.9 ± 4.0 years. Half of patients had an ANA titer ≥ 1:320. The ANA pattern was speckled in 60% of the patients. Thyroid antibodies were detected in 30% of the patients. Anti-Thyroglobulin (ATG was detected in 29% and Anti-thyroid peroxidase (ATPO in 21% of the patients; of these children, 14% had hypothyroidism. ANA pattern and titer were not associated with anti-thyroid antibody positivity. Conclusion Thyroid antibodies associated with chronic lymphocytic thyroiditis, ATG and ATPO, were detected significantly higher in ANA-positive children without a rheumatologic condition (30% as

  14. Effect of oral administration of Propionibacterium acnes on growth performance, DTH response and anti-OVA titers in goat kids

    Directory of Open Access Journals (Sweden)

    Luis Miguel Ferrer

    2013-01-01

    Full Text Available Immunostimulants are susbstances that stimuli the response of effector cells to activate the immune response such as antigen uptake, cytokine release or antibody response. These substances can increase resistence to infection by different types of microorganisms, reducing dependence of antibiotics used in livestock animals. Recent reports have demonstrated the positive effect of Propionibacterium acnes (P. acnes to control animal diseases. In this study, we evaluated the effect of the non-specific immunostimulant P. acnes on immunological functions and growth performance in goat kids. Twenty five goat kids served as control group (A and another 25 animals received P. acnes being the experimental group (B. Kids were challenged with ovalbumin (OVA to assess humoral immunity. To assess in vivo cell immunity, delayed type hypersensitivity (DTH test with phytohemagglutinin (PHA was used, clinical signs and body weight were recorded each week until 9 weeks of age when the experiment ended. Blood samples were obtained to analyze serum proteins fractions and anti-OVA specific antibodies. No clinical signs of disease and no differences (p>0.05 on body weight between groups were recorded (7.32±0.81 kg in group A, 7.13±0.65 kg in group B. Goat kids from group B had more total protein (59.8±5g/l and albumin levels (32.8±3.3g/l than goat kids from group A (56.6±5.7 g/l, 29.6±3.9 g/l respectively (p<0.05. DTH response in goat kids from group B on day 42 was higher (p<0.05 than group A. At day 63, goat kids from group receiving P. acnes had higher percentage (85.4 of anti-OVA IgM titers (p<0.05 than control group (57.7. In conclusion, the results showed that oral administration of P. acnes to goat kids improved some aspects of the immune system of the animals and it could be used to control goat diseases.

  15. Bispecific antibodies and their use in applied research

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    Harshit Verma

    Full Text Available Bispecific antibodies (BsAb can, by virtue of combining two binding specificities, improve the selectivity and efficacy of antibody-based treatment of human disease. Antibodies with two distinct binding specificities have great potential for a wide range of clinical applications as targeting agents for in vitro and in vivo immunodiagnosis, therapy and for improving immunoassays. They have shown great promise for targeting cytotoxic effector cells, delivering radionuclides, toxins or cytotoxic drugs to specific targets, particularly tumour cells. The development of BsAb research goes through three main stages: chemical cross linking of murine-derived monoclonal antibody, hybrid hybridomas and engineered BsAb. This article is providing the potential applications of bispecific antibodies. [Vet World 2012; 5(12.000: 775-780

  16. High-Throughput Tools for Characterization of Antibody Epitopes

    DEFF Research Database (Denmark)

    Christiansen, Anders

    binders. In this study, phage display screenings were used to identify peptides that could inhibit a major toxin in cobra snake venom, α-cobratoxin. Peptide inhibitors were successfully identified. Importantly, HTS enabled the identification of toxin inhibitors that were not discovered by traditional...... phage display. Phage display coupled with HTS was again used in Chapter 3 in an attempt to map the epitopes of a therapeutic target injected into animals. The animals were immunized with a therapeutic target and the expectation was that they develop antibodies, which can be used in therapy. While...

  17. Design of a titering assay for lentiviral vectors utilizing direct extraction of DNA from transduced cells in microtiter plates

    Directory of Open Access Journals (Sweden)

    Michele E Murphy

    2016-01-01

    Full Text Available Using lentiviral vector products in clinical applications requires an accurate method for measuring transduction titer. For vectors lacking a marker gene, quantitative polymerase chain reaction is used to evaluate the number of vector DNA copies in transduced target cells, from which a transduction titer is calculated. Immune Design previously described an integration-deficient lentiviral vector pseudotyped with a modified Sindbis virus envelope for use in cancer immunotherapy (VP02, of the ZVex platform. Standard protocols for titering integration-competent lentiviral vectors employ commercial spin columns to purify vector DNA from transduced cells, but such columns are not optimized for isolation of extrachromosomal (nonintegrated DNA. Here, we describe a 96-well transduction titer assay in which DNA extraction is performed in situ in the transduction plate, yielding quantitative recovery of extrachromosomal DNA. Vector titers measured by this method were higher than when commercial spin columns were used for DNA isolation. Evaluation of the method's specificity, linear range, and precision demonstrate that it is suitable for use as a lot release assay to support clinical trials with VP02. Finally, the method is compatible with titering both integrating and nonintegrating lentiviral vectors, suggesting that it may be used to evaluate the transduction titer for any lentiviral vector.

  18. Uniform Orientation of Biotinylated Nanobody as an Affinity Binder for Detection of Bacillus thuringiensis (Bt) Cry1Ac Toxin

    Science.gov (United States)

    Li, Min; Zhu, Min; Zhang, Cunzheng; Liu, Xianjin; Wan, Yakun

    2014-01-01

    Nanobodies are the smallest natural fragments with useful properties such as high affinity, distinct paratope and high stability, which make them an ideal tool for detecting target antigens. In this study, we generated and characterized nanobodies against the Cry1Ac toxin and applied them in a biotin-streptavidin based double antibodies (nanobodies) sandwich-ELISA (DAS-ELISA) assay. After immunizing a camel with soluble Cry1Ac toxin, a phage displayed library was constructed to generate Nbs against the Cry1Ac toxin. Through successive rounds of affinity bio-panning, four nanobodies with greatest diversity in CDR3 sequences were obtained. After affinity determination and conjugating to HRP, two nanobodies with high affinity which can recognize different epitopes of the same antigen (Cry1Ac) were selected as capture antibody (Nb61) and detection antibody (Nb44). The capture antibody (Nb61) was biotinylated in vivo for directional immobilization on wells coated with streptavidin matrix. Both results of specificity analysis and thermal stability determination add support for reliability of the following DAS-ELISA with a minimum detection limit of 0.005 μg·mL−1 and a working range 0.010–1.0 μg·mL−1. The linear curve displayed an acceptable correlation coefficient of 0.9976. These results indicated promising applications of nanobodies for detection of Cry1Ac toxin with biotin-streptavidin based DAS-ELISA system. PMID:25474492

  19. Uniform Orientation of Biotinylated Nanobody as an Affinity Binder for Detection of Bacillus thuringiensis (Bt Cry1Ac Toxin

    Directory of Open Access Journals (Sweden)

    Min Li

    2014-12-01

    Full Text Available Nanobodies are the smallest natural fragments with useful properties such as high affinity, distinct paratope and high stability, which make them an ideal tool for detecting target antigens. In this study, we generated and characterized nanobodies against the Cry1Ac toxin and applied them in a biotin-streptavidin based double antibodies (nanobodies sandwich-ELISA (DAS-ELISA assay. After immunizing a camel with soluble Cry1Ac toxin, a phage displayed library was constructed to generate Nbs against the Cry1Ac toxin. Through successive rounds of affinity bio-panning, four nanobodies with greatest diversity in CDR3 sequences were obtained. After affinity determination and conjugating to HRP, two nanobodies with high affinity which can recognize different epitopes of the same antigen (Cry1Ac were selected as capture antibody (Nb61 and detection antibody (Nb44. The capture antibody (Nb61 was biotinylated in vivo for directional immobilization on wells coated with streptavidin matrix. Both results of specificity analysis and thermal stability determination add support for reliability of the following DAS-ELISA with a minimum detection limit of 0.005 μg·mL−1 and a working range 0.010–1.0 μg·mL−1. The linear curve displayed an acceptable correlation coefficient of 0.9976. These results indicated promising applications of nanobodies for detection of Cry1Ac toxin with biotin-streptavidin based DAS-ELISA system.

  20. Exfoliative Toxins of Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Michal Bukowski

    2010-05-01

    Full Text Available Staphylococcus aureus is an important pathogen of humans and livestock. It causes a diverse array of diseases, ranging from relatively harmless localized skin infections to life-threatening systemic conditions. Among multiple virulence factors, staphylococci secrete several exotoxins directly associated with particular disease symptoms. These include toxic shock syndrome toxin 1 (TSST-1, enterotoxins, and exfoliative toxins (ETs. The latter are particularly interesting as the sole agents responsible for staphylococcal scalded skin syndrome (SSSS, a disease predominantly affecting infants and characterized by the loss of superficial skin layers, dehydration, and secondary infections. The molecular basis of the clinical symptoms of SSSS is well understood. ETs are serine proteases with high substrate specificity, which selectively recognize and hydrolyze desmosomal proteins in the skin. The fascinating road leading to the discovery of ETs as the agents responsible for SSSS and the characterization of the molecular mechanism of their action, including recent advances in the field, are reviewed in this article.

  1. Shiga Toxin Therapeutics: Beyond Neutralization

    Directory of Open Access Journals (Sweden)

    Gregory Hall

    2017-09-01

    Full Text Available Ribotoxic Shiga toxins are the primary cause of hemolytic uremic syndrome (HUS in patients infected with Shiga toxin-producing enterohemorrhagic Escherichia coli (STEC, a pathogen class responsible for epidemic outbreaks of gastrointestinal disease around the globe. HUS is a leading cause of pediatric renal failure in otherwise healthy children, resulting in a mortality rate of 10% and a chronic morbidity rate near 25%. There are currently no available therapeutics to prevent or treat HUS in STEC patients despite decades of work elucidating the mechanisms of Shiga toxicity in sensitive cells. The preclinical development of toxin-targeted HUS therapies has been hindered by the sporadic, geographically dispersed nature of STEC outbreaks with HUS cases and the limited financial incentive for the commercial development of therapies for an acute disease with an inconsistent patient population. The following review considers potential therapeutic targeting of the downstream cellular impacts of Shiga toxicity, which include the unfolded protein response (UPR and the ribotoxic stress response (RSR. Outcomes of the UPR and RSR are relevant to other diseases with large global incidence and prevalence rates, thus reducing barriers to the development of commercial drugs that could improve STEC and HUS patient outcomes.

  2. Biodetoxification of toxins generated from lignocellulose pretreatment using a newly isolated fungus, Amorphotheca resinae ZN1, and the consequent ethanol fermentation

    Directory of Open Access Journals (Sweden)

    Wang Wei

    2010-11-01

    Full Text Available Abstract Background Degradation of the toxic compounds generated in the harsh pretreatment of lignocellulose is an inevitable step in reducing the toxin level for conducting practical enzymatic hydrolysis and ethanol fermentation processes. Various detoxification methods have been tried and many negative outcomes were found using these methods, such as the massive freshwater usage and wastewater generation, loss of the fine lignocellulose particles and fermentative sugars and incomplete removal of inhibitors. An alternate method, biodetoxification, which degrades the toxins as part of their normal metabolism, was considered a promising option for the removal of toxins without causing the above problems. Results A kerosene fungus strain, Amorphotheca resinae ZN1, was isolated from the microbial community growing on the pretreated corn stover material. The degradation of the toxins as well as the lignocelluloses-derived sugars was characterized in different ways, and the results show that A. resinae ZN1 utilized each of these toxins and sugars as the sole carbon sources efficiently and grew quickly on the toxins. It was found that the solid-state culture of A. resinae ZN1 on various pretreated lignocellulose feedstocks such as corn stover, wheat straw, rice straw, cotton stalk and rape straw degraded all kinds of toxins quickly and efficiently. The consequent simultaneous saccharification and ethanol fermentation was performed at the 30% (wt/wt solid loading of the detoxified lignocellulosic feedstocks without a sterilization step, and the ethanol titer in the fermentation broth reached above 40 g/L using food crop residues as feedstocks. Conclusions The advantages of the present biodetoxification by A. resinae ZN1 over the known detoxification methods include zero energy input, zero wastewater generation, complete toxin degradation, processing on solid pretreated material, no need for sterilization and a wide lignocellulose feedstock spectrum

  3. Alloimmunization due to red cell antibodies in Rhesus positive Omani Pregnant Women: Maternal and Perinatal outcome

    Directory of Open Access Journals (Sweden)

    Tamima Al-Dughaishi

    2015-01-01

    Full Text Available Objective: This study is aimed to determine the prevalence of alloimmunization due to antibodies to red blood cell (RBC antigens (other than rhesus [Rh] antigen and report the maternal, perinatal, and neonatal outcomes. Materials and Methods: A retrospective review of medical records of all patients with minor RBCs antibodies alloimmunization who were followed and delivered at Sultan Qaboos University Hospital, Oman from June 2011 to June 2013. Maternal characteristics, antibody type, antibody titer in addition to perinatal and neonatal outcomes were reviewed. Results: There were 1160 patients with Rh positive status in the study. The most common ABO blood group was O, followed by A, B, and AB. We found 33 out of 1160 Rh positive women alloimmunized with minor RBCs antibodies that gave a prevalence of minor RBCs alloimmunization of 2.7%. The most frequent antibody was anti-E 38%, followed by anti-c 17% and anti-kell 17%. 6 of these 33 patients were identified to have significant antibody titer, and two cases showed evidence of fetal anemia. Only one case required an intrauterine blood transfusion. The most common neonatal complication was jaundice in 53%, followed by respiratory distress syndrome in 28%. Two cases complicated by neonatal anemia required a postnatal blood transfusion. Conclusion: Alloimmunization with anti-E, anti-c, and anti-kell were the most common antibodies among the study group. Minor RBCs alloimmunization was an important cause of neonatal morbidity.

  4. Studies in the Use of Magnetic Microspheres for Immunoaffinity Extraction of Paralytic Shellfish Poisoning Toxins from Shellfish

    Directory of Open Access Journals (Sweden)

    Christopher Elliott

    2011-01-01

    Full Text Available Paralytic shellfish poisoning (PSP is a potentially fatal human health condition caused by the consumption of shellfish containing high levels of PSP toxins. Toxin extraction from shellfish and from algal cultures for use as standards and analysis by alternative analytical monitoring methods to the mouse bioassay is extensive and laborious. This study investigated whether a selected MAb antibody could be coupled to a novel form of magnetic microsphere (hollow glass magnetic microspheres, brand name Ferrospheres-N and whether these coated microspheres could be utilized in the extraction of low concentrations of the PSP toxin, STX, from potential extraction buffers and spiked mussel extracts. The feasibility of utilizing a mass of 25 mg of Ferrospheres-N, as a simple extraction procedure for STX from spiked sodium acetate buffer, spiked PBS buffer and spiked mussel extracts was determined. The effects of a range of toxin concentrations (20–300 ng/mL, incubation times and temperature on the capability of the immuno-capture of the STX from the spiked mussel extracts were investigated. Finally, the coated microspheres were tested to determine their efficiency at extracting PSP toxins from naturally contaminated mussel samples. Toxin recovery after each experiment was determined by HPLC analysis. This study on using a highly novel immunoaffinity based extraction procedure, using STX as a model, has indicated that it could be a convenient alternative to conventional extraction procedures used in toxin purification prior to sample analysis.

  5. Mechanistic insights into the neutralization of cytotoxic abrin by the monoclonal antibody D6F10.

    Directory of Open Access Journals (Sweden)

    Shradha Bagaria

    Full Text Available Abrin, an A/B toxin obtained from the Abrus precatorius plant is extremely toxic and a potential bio-warfare agent. Till date there is no antidote or vaccine available against this toxin. The only known neutralizing monoclonal antibody against abrin, namely D6F10, has been shown to rescue the toxicity of abrin in cells as well as in mice. The present study focuses on mapping the epitopic region to understand the mechanism of neutralization of abrin by the antibody D6F10. Truncation and mutational analysis of abrin A chain revealed that the amino acids 74-123 of abrin A chain contain the core epitope and the residues Thr112, Gly114 and Arg118 are crucial for binding of the antibody. In silico analysis of the position of the mapped epitope indicated that it is present close to the active site cleft of abrin A chain. Thus, binding of the antibody near the active site blocks the enzymatic activity of abrin A chain, thereby rescuing inhibition of protein synthesis by the toxin in vitro. At 1∶10 molar concentration of abrin:antibody, the antibody D6F10 rescued cells from abrin-mediated inhibition of protein synthesis but did not prevent cell attachment of abrin. Further, internalization of the antibody bound to abrin was observed in cells by confocal microscopy. This is a novel finding which suggests that the antibody might function intracellularly and possibly explains the rescue of abrin's toxicity by the antibody in whole cells and animals. To our knowledge, this study is the first report on a neutralizing epitope for abrin and provides mechanistic insights into the poorly understood mode of action of anti-A chain antibodies against several toxins including ricin.

  6. Age Dependence and Isotype Specificity of Influenza Virus Hemagglutinin Stalk-Reactive Antibodies in Humans

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    Raffael Nachbagauer

    2016-01-01

    Full Text Available Influenza remains a major global health burden. Seasonal vaccines offer protection but can be rendered less effective when the virus undergoes extensive antigenic drift. Antibodies that target the highly conserved hemagglutinin stalk can protect against drifted viruses, and vaccine constructs designed to induce such antibodies form the basis for a universal influenza virus vaccine approach. In this study, we analyzed baseline and postvaccination serum samples of children (6 to 59 months, adults (18 to 49 years, and elderly individuals (≥65 years who participated in clinical trials with a recombinant hemagglutinin-based vaccine. We found that baseline IgG and IgA antibodies against the H1 stalk domain correlated with the ages of patients. Children generally had very low baseline titers and did not respond well to the vaccine in terms of making stalk-specific antibodies. Adults showed the highest induction of stalk-specific antibodies, but the elderly had the highest absolute antibody titers against the stalk. Importantly, the stalk antibodies measured by enzyme-linked immunosorbent assay (ELISA showed neutralizing activity in neutralization assays and protected mice in a passive-transfer model in a stalk titer-dependent manner. Finally, we found similar patterns of stalk-specific antibodies directed against the H3 and influenza B virus hemagglutinins, albeit at lower levels than those measured against the H1 stalk. The relatively high levels of stalk-specific antibodies in the elderly patients may explain the previously reported low influenza virus infection rates in this age group. (This study has been registered at ClinicalTrials.gov under registration no. NCT00336453, NCT00539981, and NCT00395174.

  7. Clinical utility of seropositive voltage-gated potassium channel–complex antibody

    Science.gov (United States)

    Jammoul, Adham; Shayya, Luay; Mente, Karin; Li, Jianbo; Rae-Grant, Alexander

    2016-01-01

    Abstract Background: Antibodies against voltage-gated potassium channel (VGKC)–complex are implicated in the pathogenesis of acquired neuromyotonia, limbic encephalitis, faciobrachial dystonic seizure, and Morvan syndrome. Outside these entities, the clinical value of VGKC-complex antibodies remains unclear. Methods: We conducted a single-center review of patients positive for VGKC-complex antibodies over an 8-year period. Results: Among 114 patients positive for VGKC-complex antibody, 11 (9.6%) carrying the diagnosis of limbic encephalitis (n = 9) or neuromyotonia (n = 2) constituted the classic group, and the remaining 103 cases of various neurologic and non-neurologic disorders comprised the nonclassic group. The median titer for the classic group was higher than the nonclassic group (p 0.25 nM) VGKC-complex antibody levels (p < 0.0001). A total of 75.0% of the patients in the high-level group had definite or probable autoimmune basis, while nonautoimmune disorders were seen in 75.6% of patients from the low-level group (p < 0.0001). A total of 26.3% of patients were found with active or remote solid organ or hematologic malignancy, but no antibody titer difference was observed among subgroups of absent, active, or remote malignancy. Compared to age-matched US national census, rates of active cancer in our cohort were higher in patients older than 45 years. Conclusions: High VGKC-complex antibody titers are more likely found in patients with classically associated syndromes and other autoimmune conditions. Low-level VGKC-complex antibodies can be detected in nonspecific and mostly nonautoimmune disorders. The presence of VGKC-complex antibody, rather than its level, may serve as a marker of malignancy. PMID:27847683

  8. Prevalence of antibodies to Toxoplasma gondii in females buffaloes in Ninavah province, Iraq

    Directory of Open Access Journals (Sweden)

    O. M. Al-Iraqi

    2008-01-01

    Full Text Available The aim of this study was to investigate the prevalence of antibodies to Toxoplasma gondii in the females of the local breed buffaloes. A 400 sera samples were collected from 49 herds from different nine geographical area in Ninavah province by using latex agglutination and modified latex agglutination tests. The results shows that the total prevalence rate of the antibodies was 30%, and this percentage was differ according to the region. The highest percentage appeared in Badosh and Qnetra at 52.3%, 51.2% respectively, while the lowest was in Hawiaslan 4.3%. The antibodies titer most appear was 80 in percentage 30.5%, while the titer 640 was lowest in percentage 1.7%. Also recorded that numbers of the active cases was highest in percentage 81.4% compared with inactive cases was lowest in percentage 18.6%, also noted that the seropositive samples decreased with age.

  9. 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.)

  10. Production and characterization of a monoclonal antibody to chicken type I collagen.

    Science.gov (United States)

    Linsenmayer, T F; Hendrix, M J; Little, C D

    1979-01-01

    We have shown that lymphocyte-myeloma cell hybridization can be used to produce large amounts of extremely high-titer specific antibodies against type I collagen, a macromolecule normally of low immunogenicity. In a passive hemagglutination assay the antibody had a high titer against chicken type I collagen but showed no activity against chicken type II or rat type I collagen. By using a two-step fluorescence histochemical procedure on sections of embryonic chicken tibia, strong fluorescence was observed in the perichondrium and surrounding connective tissue (known to contain type I collagen) but not over the cartilage (characterized by type II collagen). When used in conjunction with Staphylococcus aureus as a solid phase immunoadsorbant, the antibody was shown to bind to labeled collagen synthesized in vitro by embryonic chicken calvaria. Images PMID:291035

  11. Production and purification of polyclonal antibody against melatonin hormone

    Directory of Open Access Journals (Sweden)

    Fooladsaz K

    1999-09-01

    Full Text Available Nowadays immunochemical techniques have played a very important and valuable role in quantitative and qualitative assays of liquid compounds of the body. Producing antibody against immunogenes is the first step to make immunochemical kits. In this study production and purification of polyclonal antibody against melatonin has been considered. This hormone which has several important functions in physiological conditions such as migraine, cirrhosis, mammary gland cancer and other diseases, is the most important pineal gland secretion. This gland is a circumventricular organ of brain and according to histological and anatomical studies, it is a high secretory organ, that secretes active biological substances like melatonin, oxytocin, serotonin and ect. In this study, melatonin has been considered as hapten and has become an immunogen by being linked to the bovine serum Albumin. Then, by the immunization of three white New Zeland rabbits that had the booster injections in regular intervals, the antibody titer was detected to be 1/2000, by using checkboard curves, and with the use of melatonin linked to penicillinase as a labeled antigen, the titer was detected 1/200. Finally an antibody with high purification rate has been obtained, which can be used in immunochemical assays like RIA, ELISA, and EIA.

  12. Higher Throughput Quantification of Neutralizing Antibody to Herpes Simplex Viruses.

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    Tamara P Blevins

    Full Text Available We report a rapid, higher throughput method for measuring neutralizing antibody to herpes simplex virus (HSV in human sera. Clinical isolates and sera from the Herpevac Trial for Women were used in a colorimetric assay in which infection of tissue culture (lack of neutralization was indicated by substrate metabolism by beta-galactosidase induced in the ELVIS cell line. The neutralization assay was optimized by addition of guinea pig complement, which particularly enhanced neutralizing antibody titers to HSV-2. Higher neutralizing antibody titers were also achieved using virus particles isolated from the supernatant of infected cells rather than lysate of infected cells as the source of virus. The effect of assay incubation time and incubation time with substrate were also optimized. We found that incubating with substrate until a standard optical density of 1.0 was reached permitted a better comparison among virus isolates, and achieved reliable measurement of neutralizing antibody activity. Interestingly, in contrast to results in the absence of complement, addition of complement allowed sera from HSV-2 gD-vaccinated subjects to neutralize HSV-1 and HSV-2 clinical and laboratory isolates with equal potency.

  13. Higher Throughput Quantification of Neutralizing Antibody to Herpes Simplex Viruses.

    Science.gov (United States)

    Blevins, Tamara P; Mitchell, Michelle C; Korom, Maria; Wang, Hong; Yu, Yinyi; Morrison, Lynda A; Belshe, Robert B

    2015-01-01

    We report a rapid, higher throughput method for measuring neutralizing antibody to herpes simplex virus (HSV) in human sera. Clinical isolates and sera from the Herpevac Trial for Women were used in a colorimetric assay in which infection of tissue culture (lack of neutralization) was indicated by substrate metabolism by beta-galactosidase induced in the ELVIS cell line. The neutralization assay was optimized by addition of guinea pig complement, which particularly enhanced neutralizing antibody titers to HSV-2. Higher neutralizing antibody titers were also achieved using virus particles isolated from the supernatant of infected cells rather than lysate of infected cells as the source of virus. The effect of assay incubation time and incubation time with substrate were also optimized. We found that incubating with substrate until a standard optical density of 1.0 was reached permitted a better comparison among virus isolates, and achieved reliable measurement of neutralizing antibody activity. Interestingly, in contrast to results in the absence of complement, addition of complement allowed sera from HSV-2 gD-vaccinated subjects to neutralize HSV-1 and HSV-2 clinical and laboratory isolates with equal potency.

  14. Prediction and Reduction of the Aggregation of Monoclonal Antibodies.

    Science.gov (United States)

    van der Kant, Rob; Karow-Zwick, Anne R; Van Durme, Joost; Blech, Michaela; Gallardo, Rodrigo; Seeliger, Daniel; Aßfalg, Kerstin; Baatsen, Pieter; Compernolle, Griet; Gils, Ann; Studts, Joey M; Schulz, Patrick; Garidel, Patrick; Schymkowitz, Joost; Rousseau, Frederic

    2017-04-21

    Protein aggregation remains a major area of focus in the production of monoclonal antibodies. Improving the intrinsic properties of antibodies can improve manufacturability, attrition rates, safety, formulation, titers, immunogenicity, and solubility. Here, we explore the potential of predicting and reducing the aggregation propensity of monoclonal antibodies, based on the identification of aggregation-prone regions and their contribution to the thermodynamic stability of the protein. Although aggregation-prone regions are thought to occur in the antigen binding region to drive hydrophobic binding with antigen, we were able to rationally design variants that display a marked decrease in aggregation propensity while retaining antigen binding through the introduction of artificial aggregation gatekeeper residues. The reduction in aggregation propensity was accompanied by an increase in expression titer, showing that reducing protein aggregation is beneficial throughout the development process. The data presented show that this approach can significantly reduce liabilities in novel therapeutic antibodies and proteins, leading to a more efficient path to clinical studies. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. 18F-FDG PET/CT findings preceded elevation of serum proteinase 3 antineutrophil cytoplasmic antibodies in Wegener granulomatosis.

    Science.gov (United States)

    Ito, Kimiteru; Minamimoto, Ryogo; Yamashita, Hiroyuki; Morooka, Miyako; Okasaki, Momoko; Mimori, Akio; Kubota, Kazuo

    2014-01-01

    A 67-year-old woman underwent F-FDG PET/CT after developing a fever of unknown origin. PET/CT revealed intensive FDG uptake at the nasal and lung lesions. On the laboratory data, serum myeloperoxidase antineutrophil cytoplasmic antibodies (ANCA) titer was elevated, although serum directed against proteinase 3 (PR3) ANCA titer was within normal limits. One month after treatment, follow-up PET/CT revealed decreased FDG uptake at the lesions. One year later, serum PR3-ANCA titer elevated, which finally led to a diagnosis of Wegener granulomatosis (WG). WG lesions may be detected earlier by FDG PET/CT than by serum PR3-ANCA titers.

  16. Anti-Ro52 antibody level is an important marker of fetal congenital heart block risk in anti-Ro/SSA antibody positive pregnancy.

    Science.gov (United States)

    Miyasato-Isoda, Mai; Waguri, Masako; Yamada, Yuko; Miyano, Akira; Wada, Yoshinao

    2017-09-21

    The aims of this study are to determine the incidence of congenital heart block (CHB) in the Japanese population and identify maternal factors predicting fetal CHB in anti-Ro/SSA antibody positive pregnancy. A retrospective study was performed using 52,147 clinical records of pregnancies followed in a single center. For 183 anti-Ro/SSA antibody-positive women, anti-Ro52 and Ro60 antibodies were measured, and the odds of CHB in relation to maternal clinical features were calculated by multivariate analysis. The receiver-operating characteristic (ROC) curves for predicting CHB were constructed for the titers of anti-Ro/SSA, anti-Ro52 and anti-Ro60 antibodies. Fetal CHB occurred in two pregnancies among those without known risks such as positive anti-Ro/SSA antibody or previous CHB-affected pregnancy, suggesting an incidence similar to that in Caucasian populations. As for the anti-Ro/SSA antibody positive pregnancies, the titers of anti-Ro/SSA, anti-Ro52 and anti-Ro60 antibodies were independent risk factors for fetal CHB and the use of corticosteroids before 18 gestational weeks was an independent protective factor. The area under the ROC was 0.84, 0.73 and 0.74 for anti-Ro52, anti-Ro60 and anti-Ro/SSA antibodies, respectively. CHB occurred in two among approximately 50,000 pregnancies without known risks such as positive anti-Ro/SSA antibody or previous delivery of CHB-affected babies. Measurement of anti-Ro52 antibody levels may be helpful in extracting a risk group of delivering CHB infants in the anti-Ro/SSA antibody positive pregnancy.

  17. Toxin production in Dinophysis and the fate of these toxins in marine mussels

    DEFF Research Database (Denmark)

    Nielsen, Lasse Tor

    Diarrhetic shellfish poisoning (DSP) poses a considerable threat to food safety and to the economy of shellfish fishers and farmers in many parts of the world. Thousands of DSP intoxications have been reported, and bivalve harvesting can sometimes be closed down several months in a row. The toxins....... acuta. I grew the two species in laboratory cultures at different irradiances (7-130 μmol photons m-2 s-1) and with different food availability. The results showed that irradiance had no effects on toxin profiles, and only limited effects of the cellular toxin contents. Rather, toxin production rates...... followed growth rates, thus giving stable toxin contents. Food availability also did not change the toxin profiles of either species, but starvation did increase the cellular contents of each of the toxins present. The observation that toxin production continued for several weeks after the ciliate food...

  18. Aqueous Extracts of Hibiscus sabdariffa Calyces Decrease Hepatitis A Virus and Human Norovirus Surrogate Titers.

    Science.gov (United States)

    Joshi, Snehal S; Dice, Lezlee; D'Souza, Doris H

    2015-12-01

    Hibiscus sabdariffa extract is known to have antioxidant, anti-diabetic, and antimicrobial properties. However, their effects against foodborne viruses are currently unknown. The objective of this study was to determine the antiviral effects of aqueous extracts of H. sabdariffa against human norovirus surrogates (feline calicivirus (FCV-F9) and murine norovirus (MNV-1)) and hepatitis A virus (HAV) at 37 °C over 24 h. Individual viruses (~5 log PFU/ml) were incubated with 40 or 100 mg/ml of aqueous hibiscus extract (HE; pH 3.6), protocatechuic acid (PCA; 3 or 6 mg/ml, pH 3.6), ferulic acid (FA; 0.5 or 1 mg/ml; pH 4.0), malic acid (10 mM; pH 3.0), or phosphate buffered saline (pH 7.2 as control) at 37 °C over 24 h. Each treatment was replicated thrice and plaque assayed in duplicate. FCV-F9 titers were reduced to undetectable levels after 15 min with both 40 and 100 mg/ml HE. MNV-1 was reduced by 1.77 ± 0.10 and 1.88 ± 0.12 log PFU/ml after 6 h with 40 and 100 mg/ml HE, respectively, and to undetectable levels after 24 h by both concentrations. HAV was reduced to undetectable levels by both HE concentrations after 24 h. PCA at 3 mg/ml reduced FCV-F9 titers to undetectable levels after 6 h, MNV-1 by 0.53 ± 0.01 log PFU/ml after 6 h, and caused no significant change in HAV titers. FA reduced FCV-F9 to undetectable levels after 3 h and MNV-1 and HAV after 24 h. Transmission electron microscopy showed no conclusive results. The findings suggest that H. sabdariffa extracts have potential to prevent foodborne viral transmission.

  19. THE PERSISTENCE OF LEPTOSPIRAL AGGLUTININS TITERS IN HUMAN SERA DIAGNOSED BY THE MICROSCOPIC AGGLUTINATION TEST

    Directory of Open Access Journals (Sweden)

    Eliete C. ROMERO

    1998-05-01

    Full Text Available The persistence of agglutinins detected by MAT has created some problems to the interpretation of the results. The aim of this study was to examine the data of serology from 70 patients with serologically confirmed diagnosis of leptospirosis by during 3-13 months after being affected with leptospires in order to elucidate the interpretation of the persistence of agglutinins detected by MAT. Sixty-one patients sera (87.14% had titers equal or greater than 800. Of these, two individuals maintained titers of 800 thirteen months after the onset. This study showed that only one sample of sera with high titers is not reliable to determine the time at which infection occurred.Persistência de títulos de aglutininas anti-leptospiras em soros humanos diagnosticados pelo teste de aglutinação microscópica A persistência de aglutininas detectadas por MAT tem criado problemas na interpretação dos resultados. O objetivo deste trabalho foi examinar os resultados da sorologia de 70 pacientes com confirmação sorológica de leptospirose durante 3-13 meses após terem sido infectados para se poder elucidar a interpretação da persistência de aglutininas detectadas por MAT. Sessenta e um soros de pacientes (87,14% apresentaram títulos iguais, ou maiores, que 800. Destes, 2 indivíduos mantiveram títulos de 800 treze meses após terem sido infectados. Este estudo mostra que apenas uma amostra de soro, mesmo com alto título de aglutininas, não pode ser considerada para determinar a fase da doença.

  20. [Distribution of serum antibodies against human papillomavirus 16 and 18 among high-risk women to cervical cancer].

    Science.gov (United States)

    Fei, Mandong; Li, Jiayuan; Du, Jingchang; You, Jia; Zhang, Shaokai; He, Wei; Kang, Leni; Zhao, Fanghui; Qiao, Youlin; Si, Yuzhi; Fan, Xiaoping; Chen, Wen

    2014-05-01

    To explore the distribution of serum antibodies against human papillomavirus (HPV) 16/18 among women at high-risk for cervical cancer. All women when tested positive for anyone of the cervical cancer screening programs, from Xinmi county of Henan province in 2011, were recruited as the subjects of this study. Cervical exfoliated cells were collected, using cervical brush for HPV DNA testing, and 10 ml venous blood was drawn for HPV-16, 18 serum antibodies testing, by enzyme-linked immunosorbent assay. Among the 952 women under study, 230 cases (24.2%)showed HPV DNA positive, with positivity rates of HPV16 and 18 L1 virus-like particle (VLP)antibodies as 23.2% and 6.5%, respectively. The overall positivity rate of any type of HPV16, 18 VLP antibodies was 26.8% . Geometric means of HPV16, 18 VLP antibody titers were 79.1 (Yangshengtang Unit,YU/ml) and 125.0(YU/ml). Positivity rate of HPV16 antibody was significantly associated with age, viral load of HPV DNA, and cervical lesion severity (P antibodies than women who did not have HPV infection or emerging infection (P antibodies and titer of HPV16 antibody (P antibodies were correlated with age, viral load, cervical lesion and history of infection.Women with high viral load, high grade cervical lesion or history of infection would more likely to be seropositive.

  1. Computational Studies of Snake Venom Toxins

    OpenAIRE

    Paola G. Ojeda; David Ramírez; Jans Alzate-Morales; Julio Caballero; Quentin Kaas; Wendy González

    2017-01-01

    Most snake venom toxins are proteins, and participate to envenomation through a diverse array of bioactivities, such as bleeding, inflammation, and pain, cytotoxic, cardiotoxic or neurotoxic effects. The venom of a single snake species contains hundreds of toxins, and the venoms of the 725 species of venomous snakes represent a large pool of potentially bioactive proteins. Despite considerable discovery efforts, most of the snake venom toxins are still uncharacterized. Modern bioinformatics t...

  2. Generation of high-titer viral preparations by concentration using successive rounds of ultracentrifugation

    Directory of Open Access Journals (Sweden)

    Ichim Christine V

    2011-08-01

    Full Text Available Abstract Background Viral vectors provide a method of stably introducing exogenous DNA into cells that are not easily transfectable allowing for the ectopic expression or silencing of genes for therapeutic or experimental purposes. However, some cell types, in particular bone marrow cells, dendritic cells and neurons are difficult to transduce with viral vectors. Successful transduction of such cells requires preparation of highly concentrated viral stocks, which permit a high virus concentration and multiplicity of infection (MOI during transduction. Pseudotyping with the vesicular stomatitis virus G (VSV-G envelope protein is common practice for both lentiviral and retroviral vectors. The VSV-G glycoprotein adds physical stability to retroviral particles, allowing concentration of virus by high-speed ultracentrifugation. Here we describe a method report for concentration of virus from large volumes of culture supernatant by means of successive rounds of ultracentrifugation into the same ultracentrifuge tube. Method Stable retrovirus producer cell lines were generated and large volumes of virus-containing supernatant were produced. We then tested the transduction ability of virus following varying rounds of concentration by ultra-centrifugation. In a second series of experiments lentivirus-containing supernatant was produced by transient transfection of 297T/17 cells and again we tested the transduction ability of virus following multiple rounds of ultra-centrifugation. Results We report being able to centrifuge VSV-G coated retrovirus for as many as four rounds of ultracentrifugation while observing an additive increase in viral titer. Even after four rounds of ultracentrifugation we did not reach a plateau in viral titer relative to viral supernatant concentrated to indicate that we had reached the maximum tolerated centrifugation time, implying that it may be possible to centrifuge VSV-G coated retrovirus even further should it be necessary

  3. Augmenting the Efficacy of Immunotoxins and Other Targeted Protein Toxins by Endosomal Escape Enhancers

    Directory of Open Access Journals (Sweden)

    Hendrik Fuchs

    2016-07-01

    Full Text Available The toxic moiety of almost all protein-based targeted toxins must enter the cytosol of the target cell to mediate its fatal effect. Although more than 500 targeted toxins have been investigated in the past decades, no antibody-targeted protein toxin has been approved for tumor therapeutic applications by the authorities to date. Missing efficacy can be attributed in many cases to insufficient endosomal escape and therefore subsequent lysosomal degradation of the endocytosed toxins. To overcome this drawback, many strategies have been described to weaken the membrane integrity of endosomes. This comprises the use of lysosomotropic amines, carboxylic ionophores, calcium channel antagonists, various cell-penetrating peptides of viral, bacterial, plant, animal, human and synthetic origin, other organic molecules and light-induced techniques. Although the efficacy of the targeted toxins was typically augmented in cell culture hundred or thousand fold, in exceptional cases more than million fold, the combination of several substances harbors new problems including additional side effects, loss of target specificity, difficulties to determine the therapeutic window and cell type-dependent variations. This review critically scrutinizes the chances and challenges of endosomal escape enhancers and their potential role in future developments.

  4. Immunogenicity of phospholipase A2 toxins and their role in Streptococcus equi pathogenicity.

    Science.gov (United States)

    López-Álvarez, M R; Salze, M; Cenier, A; Robinson, C; Paillot, R; Waller, A S

    2017-05-01

    Streptococcus equi subsp. equi (S. equi) is the causative agent of strangles, one of the most frequently diagnosed infectious diseases of horses worldwide. Phospholipase A 2 toxins (PLA 2 ) cleave phospholipid molecules at position sn-2 contributing to the production of leukotrienes that are important inflammatory mediators. Two homologous phospholipases, SlaA and SlaB are encoded by the S. equi genome suggesting that PLA 2 toxins may contribute to its pathogenicity. Here we report the immunogenicity and role of PLA 2 toxins during natural and experimental infection of horses with S. equi. The levels of anti-PLA 2 specific antibodies in serum from horses naturally exposed to S. equi or without exposure were measured by indirect ELISA. Furthermore, the importance of PLA 2 was determined during experimental infection of Welsh Mountain ponies with a mutant strain of S. equi lacking slaA and slaB. Our results show that PLA 2 toxins are immunogenic, which supports their production during natural S. equi infection, but that these toxins are not essential for the development of strangles in a susceptible natural host. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Risk factors for inadequate antibody response to primary rabies vaccination in dogs under one year of age

    Science.gov (United States)

    Wallace, Ryan M.; Pees, Anna; Blanton, Jesse B.

    2017-01-01

    Ensuring the adequacy of response to rabies vaccination in dogs is important, particularly in the context of pet travel. Few studies have examined the factors associated with dogs’ failure to achieve an adequate antibody titer after vaccination (0.5 IU/ml). This study evaluated rabies antibody titers in dogs after primary vaccination. Dogs under one year of age whose serum was submitted to a reference laboratory for routine diagnostics, and which had no prior documented history of vaccination were enrolled (n = 8,011). Geometric mean titers (GMT) were calculated and univariate analysis was performed to assess factors associated with failure to achieve 0.5 IU/mL. Dogs vaccinated at >16 weeks of age had a significantly higher GMT compared to dogs vaccinated at a younger age (1.64 IU/ml, 1.57–1.72, ANOVA p vaccinated vaccinated 12–16 weeks (1.22 IU/ml and 1.21 IU/ml). The majority of dogs failed to reach an adequate titer within the first 3 days of primary vaccination; failure rates were also high if the interval from vaccination to titer check was greater than 90 days. Over 90% of dogs that failed primary vaccination were able to achieve adequate titers after booster vaccination. The ideal timing for blood draw is 8–30 days after primary vaccination. In the event of a failure, most dogs will achieve an adequate serologic response upon a repeat titer (in the absence of booster vaccination). Booster vaccination after failure provided the highest probability of an acceptable titer. PMID:28759602

  6. Risk factors for inadequate antibody response to primary rabies vaccination in dogs under one year of age.

    Science.gov (United States)

    Wallace, Ryan M; Pees, Anna; Blanton, Jesse B; Moore, Susan M

    2017-07-01

    Ensuring the adequacy of response to rabies vaccination in dogs is important, particularly in the context of pet travel. Few studies have examined the factors associated with dogs' failure to achieve an adequate antibody titer after vaccination (0.5 IU/ml). This study evaluated rabies antibody titers in dogs after primary vaccination. Dogs under one year of age whose serum was submitted to a reference laboratory for routine diagnostics, and which had no prior documented history of vaccination were enrolled (n = 8,011). Geometric mean titers (GMT) were calculated and univariate analysis was performed to assess factors associated with failure to achieve 0.5 IU/mL. Dogs vaccinated at >16 weeks of age had a significantly higher GMT compared to dogs vaccinated at a younger age (1.64 IU/ml, 1.57-1.72, ANOVA p dogs vaccinated dogs vaccinated 12-16 weeks (1.22 IU/ml and 1.21 IU/ml). The majority of dogs failed to reach an adequate titer within the first 3 days of primary vaccination; failure rates were also high if the interval from vaccination to titer check was greater than 90 days. Over 90% of dogs that failed primary vaccination were able to achieve adequate titers after booster vaccination. The ideal timing for blood draw is 8-30 days after primary vaccination. In the event of a failure, most dogs will achieve an adequate serologic response upon a repeat titer (in the absence of booster vaccination). Booster vaccination after failure provided the highest probability of an acceptable titer.

  7. Prevalence of Toxoplasma gondii antibodies in barren-ground caribou (Rangifer tarandus groenlandicus) from the Canadian Arctic.

    Science.gov (United States)

    Kutz, S J; Elkin, B T; Panayi, D; Dubey, J P

    2001-04-01

    Prevalence of antibodies to Toxoplasma gondii was determined in 147 barren-ground caribou (Rangifer tarandus groenlandicus) from 5 herds in the Northwest Territories and Nunavut, northern Canada, by the modified agglutination test (MAT). In the mainland herds (Bluenose, Bathurst, and Beverly), antibodies were found in 43 (37%) of 117 caribou, and MAT titers were 1:25 in 10, 1:50 in 24, and 1:500 in 9. In the island herds, only 1 (4.3%) of 23 animals sampled from the North Baffin Island herd was positive (titer = 1:25) and no antibodies were detected in 7 caribou from the Dolphin and Union herd. The high prevalence of antibodies to T. gondii in the mainland caribou herds indicates that caribou meat may contain viable T. gondii.

  8. Filamentous phage as an immunogenic carrier to elicit focused antibody responses against a synthetic peptide

    Science.gov (United States)

    van Houten, N.E.; Zwick, M.B.; Menendez, A.; Scott, J.K.

    2007-01-01

    Filamentous bacteriophage are widely used as immunogenic carriers for “phage-displayed” recombinant peptides. Here we report that they are an effective immunogenic carrier for synthetic peptides. The f1.K phage was engineered to have an additional Lys residue near the N-terminus of the major coat protein, pVIII, so as to enhance access to chemical cross-linking agents. The dimeric synthetic peptide, B2.1, was conjugated to f1.K (f1.K/B2.1) in high copy number and compared as an immunogen to B2.1 conjugated to ovalbumin (OVA/B2.1) and to phage-displayed, recombinant B2.1 peptide. All immunogens were administered without adjuvant. The serum antibody titers were measured against: the peptide, the carrier, and, if appropriate, the cross-linker. All immunogens elicited anti-peptide antibody titers, with those elicited by OVA/B2.1 exceeding those by f1.K/B2.1; both titers were greater than that elicited by recombinant B2.1 phage. Comparison of the anti-peptide and anti-carrier antibody responses showed that f1.K/B2.1 elicited a more focused anti-peptide antibody response than OVA/B2.1. The anti-peptide antibody response against f1.K/B2.1 was optimized for the injection route, dose and adjuvant. Dose and adjuvant did not have a significant effect on anti-peptide antibody titers, but a change in injection route from intraperitoneal (IP) to subcutaneous (SC) enhanced anti-peptide antibody titers after seven immunizations. The optimized anti-peptide antibody response exceeded the anti-carrier one by 21-fold, compared to 0.07-fold elicited by OVA/B2.1. This indicates that phage as a carrier can focus the antibody response against the peptide. The results are discussed with respect to the advantages of phage as an alternative to traditional carrier proteins for synthetic peptides, carbohydrates and haptens, and to further improvements in phage as immunogenic carriers. PMID:16488517

  9. Production of high-titer human influenza A virus with adherent and suspension MDCK cells cultured in a single-use hollow fiber bioreactor.

    Science.gov (United States)

    Tapia, Felipe; Vogel, Thomas; Genzel, Yvonne; Behrendt, Ilona; Hirschel, Mark; Gangemi, J David; Reichl, Udo

    2014-02-12

    Hollow fiber bioreactors (HFBRs) have been widely described as capable of supporting the production of highly concentrated monoclonal antibodies and recombinant proteins. Only recently HFBRs have been proposed as new single-use platforms for production of high-titer influenza A virus. These bioreactors contain multiple hollow fiber capillary tubes that separate the bioreactor in an intra- and an extra-capillary space. Cells are usually cultured in the extra-capillary space and can grow to a very high cell concentration. This work describes the evaluation of the single-use hollow fiber bioreactor PRIMER HF (Biovest International Inc., USA) for production of influenza A virus. The process was setup, characterized and optimized by running a total of 15 cultivations. The HFBRs were seeded with either adherent or suspension MDCK cells, and infected with influenza virus A/PR/8/34 (H1N1), and the pandemic strain A/Mexico/4108/2009 (H1N1). High HA titers and TCID₅₀ of up to 3.87 log₁₀(HA units/100 μL) and 1.8 × 10(10)virions/mL, respectively, were obtained for A/PR/8/34 influenza strain. Influenza virus was collected by performing multiple harvests of the extra-capillary space during a virus production time of up to 12 days. Cell-specific virus yields between 2,000 and 8,000 virions/cell were estimated for adherent MDCK cells, and between 11,000 and 19,000 virions/cell for suspension MDCK.SUS2 cells. These results do not only coincide with the cell-specific virus yields obtained with cultivations in stirred tank bioreactors and other high cell density systems, but also demonstrate that HFBRs are promising and competitive single-use platforms that can be considered for commercial production of influenza virus. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Exploration of immunoglobulin transcriptomes from mice immunized with three-finger toxins and phospholipases A2 from the Central American coral snake, Micrurus nigrocinctus

    Directory of Open Access Journals (Sweden)

    Andreas H. Laustsen

    2017-01-01

    Full Text Available Snakebite envenomings represent a neglected public health issue in many parts of the rural tropical world. Animal-derived antivenoms have existed for more than a hundred years and are effective in neutralizing snake venom toxins when timely administered. However, the low immunogenicity of many small but potent snake venom toxins represents a challenge for obtaining a balanced immune response against the medically relevant components of the venom. Here, we employ high-throughput sequencing of the immunoglobulin (Ig transcriptome of mice immunized with a three-finger toxin and a phospholipase A2 from the venom of the Central American coral snake, Micrurus nigrocinctus. Although exploratory in nature, our indicate results showed that only low frequencies of mRNA encoding IgG isotypes, the most relevant isotype for therapeutic purposes, were present in splenocytes of five mice immunized with 6 doses of the two types of toxins over 90 days. Furthermore, analysis of Ig heavy chain transcripts showed that no particular combination of variable (V and joining (J gene segments had been selected in the immunization process, as would be expected after a strong humoral immune response to a single antigen. Combined with the titration of toxin-specific antibodies in the sera of immunized mice, these data support the low immunogenicity of three-finger toxins and phospholipases A2found in M. nigrocinctusvenoms, and highlight the need for future studies analyzing the complexity of antibody responses to toxins at the molecular level.

  11. Investigating Antivenom Function and Cross-Reactivity – a Study of Antibodies and Their Targets

    DEFF Research Database (Denmark)

    Engmark, Mikael; De Masi, Federico; Andersen, Mikael Rørdam

    Venomous snakebites are regarded as one of the World’s most neglected tropical diseases/conditions with up to 2.5 million victims every year. The best-practice treatment is antivenom derived from the blood of large mammals (typically horses or sheep) immunized with venom of one or more snake...... species. The active toxin neutralizing components in antivenom are complex mixtures of antibodies (or fragments here of). The individual antibodies are adapted by the immune system of the production animal to bind specific to parts of each toxin used in the immunization procedure. In many cases antivenom...

  12. Unravelling the role of allo-antibodies and Transplant Injury

    Directory of Open Access Journals (Sweden)

    Yoshiko Matsuda

    2016-10-01

    Full Text Available Alloimmunity driving rejection in the context of solid organ transplantation can be grossly divided into mechanisms predominantly driven by either T cell-mediated rejection (TCMR or antibody-mediated rejection (ABMR, though the co-existence of both types of rejections can be seen in a variable number of sampled grafts. Acute TCMR can generally be well controlled by the establishment of effective immunosuppression 1, 2. Acute ABMR is a low frequency finding in the current era of blood group and HLA donor/recipient matching and the avoidance of engraftment in the context of high-titer, pre-formed donor specific antibodies. However, chronic ABMR remains a major complication resulting in the untimely loss of transplanted organs 3-10. The close relationship between donor-specific antibodies (DSAs and ABMR has been revealed by the highly sensitive detection of human leukocyte antigen (HLA antibodies 11-16. Injury to transplanted organs by activation of humoral immune reaction in the context of HLA identical transplants and the absence of donor specific antibodies (DSAs, strongly suggest the participation of non HLA (nHLA antibodies in ABMR (17-25. In this review, we discuss the genesis of ABMR in the context of HLA and nHLA antibodies and summarize strategies for ABMR management.

  13. Combined tetanus-diphtheria and pertussis vaccine during pregnancy: transfer of maternal pertussis antibodies to the newborn.

    Science.gov (United States)

    Vilajeliu, Alba; Goncé, Anna; López, Marta; Costa, Josep; Rocamora, Laura; Ríos, José; Teixidó, Irene; Bayas, José M

    2015-02-18

    Pertussis is currently an emerging public health concern in some countries with high vaccination coverage. It is expected that maternal pertussis immunization could provide newborn protection. We compared pertussis toxin antibody (anti-PT) levels in women during pregnancy (pre- and post-vaccination) with respect to levels in the newborn at delivery in women vaccinated during pregnancy. We also estimated anti-PT titers at primary infant vaccination. Observational study of pregnant women vaccinated with Tdap (≥20 weeks gestation) and their newborns between May 2012 and August 2013. Anti-PT levels were determined by ELISA in maternal (pre- and post-vaccination) and newborn blood. Pre-vaccination, post-vaccination maternal and newborn samples were available in 132 subjects. Mean maternal age was 34.2 (SD 4.3) years. Median weeks of gestation at vaccination were 27.2 (Q1-Q3 21.7-30.8). Anti-PT (≥10 IU/ml) levels were found in 37.1% of maternal pre-vaccination samples (geometric mean titer (GMT) 7.9 IU/ml (95% CI 6.8-9.2)), 90.2% of post-vaccination samples (GMT 31.1 IU/ml (95% CI 26.6-36.3)) and 94.7% of newborns (GMT 37.8 IU/ml (95% CI 32.3-44.1)). The Lin concordance index between post-vaccination maternal and newborn samples was 0.8 (95% CI 0.8-0.9). Transplacental transfer ratio was 146.6%. At two months of age, 66% of newborns had estimated anti-PT levels ≥10 IU/ml. There was a high correlation between anti-PT levels in mothers and newborns, with higher levels in newborns, which should be sufficient to provide protection against pertussis during the first months of life. Vaccination of pregnant women seems to be an immunogenic strategy to protect newborns until primary infant immunization. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. High-titer biosynthesis of hyaluronic acid by recombinant Corynebacterium glutamicum.

    Science.gov (United States)

    Cheng, Fangyu; Gong, Qianying; Yu, Huimin; Stephanopoulos, Gregory

    2016-03-01

    Hyaluronic acid (HA) plays important roles in human tissue system, thus it is highly desirable for various applications, such as in medical, clinic and cosmetic fields. The wild microbial producer of HA, streptococcus, was restricted by its potential pathogens, hence different recombinant hosts are being explored. In this work, we engineered Corynebacterium glutamicum, a GRAS (Generally Recognized as Safe) organism free of exotoxins and endotoxins to produce HA with high titer and satisfied Mw . The ssehasA gene encoding hyaluronan synthase (HasA) was artificially synthesized with codon preference of C. glutamicum. Other genes involved in the HA synthetic pathway were directly cloned from the C. glutamicum genome. The operon structures and constitutive or inducible promoters were particularly compared and the preferred environmental conditions were also optimized. Using glucose and corn syrup powder as carbon and nitrogen sources, batch cultures of the engineered C.glutamicum with operon ssehasA-hasB driven by Ptac promoter were performed in a 5 L fermentor. The maximal HA titer, productivity and yield reached 8.3 g/L, 0.24 g/L/h and 0.22 gHA/gGlucose, respectively; meanwhile the maximal Mw was 1.30 MDa. This work provides a safe and efficient novel producer of HA with huge industrial prospects. Copyright © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. A Novel Redoxin in the Thylakoid Membrane Regulates the Titer of Photosystem I.

    Science.gov (United States)

    Zhu, Yuehui; Liberton, Michelle; Pakrasi, Himadri B

    2016-09-02

    In photosynthetic organisms like cyanobacteria and plants, the main engines of oxygenic photosynthesis are the pigment-protein complexes photosystem I (PSI) and photosystem II (PSII) located in the thylakoid membrane. In the cyanobacterium Synechocystis sp. PCC 6803, the slr1796 gene encodes a single cysteine thioredoxin-like protein, orthologs of which are found in multiple cyanobacterial strains as well as chloroplasts of higher plants. Targeted inactivation of slr1796 in Synechocystis 6803 resulted in compromised photoautotrophic growth. The mutant displayed decreased chlorophyll a content. These changes correlated with a decrease in the PSI titer of the mutant cells, whereas the PSII content was unaffected. In the mutant, the transcript levels of genes for PSI structural and accessory proteins remained unaffected, whereas the levels of PSI structural proteins were severely diminished, indicating that Slr1796 acts at a posttranscriptional level. Biochemical analysis indicated that Slr1796 is an integral thylakoid membrane protein. We conclude that Slr1796 is a novel regulatory factor that modulates PSI titer. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. High titer ethanol and lignosulfonate production from SPORL pretreated poplar at pilot-scale

    Directory of Open Access Journals (Sweden)

    Junyong (J.Y. eZhu

    2015-04-01

    Full Text Available Poplar NE222 (Populus deltoides Bartr. ex Marsh × P. nigra L. wood chips were pretreated in a 390 L pilot-scale rotating wood-pulping digester using a dilute sulfite solution of approximately pH  1.8 at 160°C for 40 min for bioconversion to ethanol and lignosulfonate (LS. An estimated combined hydrolysis factor (CHF of 3.3 was used to scale the pretreatment temperature and time from laboratory bench scale experiments, which balanced sugar yield and inhibitor formation to facilitate high titer ethanol production through fermentation using S. cerevisiae YRH400 without detoxification. A terminal ethanol titer of 43.6 g L-1 with a yield of 247 L tonne wood-1 was achieved at total solids loading of 20%. The relatively low ethanol yield compared with yield from SPORL-pretreated softwoods was due to inefficient utilization of xylose. The LS from SPORL has a substantially higher phenolic group (Ph-OH content although it is less sulfonated and has a lower molecular weight than a purified commercial softwood LS, and therefore has potential for certain commercial markets and future novel applications through further processing.

  17. High Titer Ethanol and Lignosulfonate Production from SPORL Pretreated Poplar at Pilot Scale

    International Nuclear Information System (INIS)

    Zhou, Haifeng; Zhu, J. Y.; Gleisner, Roland; Qiu, Xueqing; Horn, Eric

    2015-01-01

    Poplar NE222 (Populus deltoides Bartr. ex Marsh × P. nigra L.) wood chips were pretreated in a 390 L pilot-scale rotating wood-pulping digester using a dilute sulfite solution of approximately pH 1.8 at 160°C for 40 min for bioconversion to ethanol and lignosulfonate (LS). An estimated combined hydrolysis factor (CHF) of 3.3 was used to scale the sulfite pretreatment temperature and time from laboratory bench scale experiments, which balanced sugar yield and inhibitor formation to facilitate high titer ethanol production through fermentation using S. cerevisiae YRH400 without detoxification. A terminal ethanol titer of 43.6 g L -1 with a yield of 247 L tonne wood -1 was achieved at total solids loading of 20%. The relatively low ethanol yield compared with yield from Sulfite pretreatment to overcome the recalcitrance of lignocelluloses (SPORL)-pretreated softwoods was due to inefficient utilization of xylose. The LS from SPORL has a substantially higher phenolic group (Ph-OH) content, though it was less sulfonated and had a lower molecular weight than a purified commercial softwood LS, and therefore has potential for certain commercial markets and future novel applications through further processing. The conversion efficiency achieved through process integration and simplification, demonstrated here, has significant importance to the entire supply chain of biofuel production from woody biomass.

  18. Circulating CXCR5+PD-1+ response predicts influenza vaccine antibody responses in young adults but not elderly adults

    OpenAIRE

    Herati, Ramin Sedaghat; Reuter, Morgan A.; Dolfi, Douglas V.; Mansfield, Kathleen D.; Aung, Htin; Badwan, Osama Z.; Kurupati, Raj K.; Kannan, Senthil; Ertl, Hildegund; Schmader, Kenneth E.; Betts, Michael R.; Canaday, David H.; Wherry, E. John

    2014-01-01

    Although influenza vaccination is recommended for all adults annually, the incidence of vaccine failure, defined as weak or absent increase in neutralizing antibody titers, is increased in the elderly compared to young adults. The T follicular helper subset of CD4 T cells (Tfh) provides B cell help in germinal centers and is necessary for class-switched antibody responses. Previous studies suggested a role for circulating T follicular helper cells (cTfh) following influenza vaccination in adu...

  19. High-throughput pseudovirion-based neutralization assay for analysis of natural and vaccine-induced antibodies against human papillomaviruses.

    Directory of Open Access Journals (Sweden)

    Peter Sehr

    Full Text Available A highly sensitive, automated, purely add-on, high-throughput pseudovirion-based neutralization assay (HT-PBNA with excellent repeatability and run-to-run reproducibility was developed for human papillomavirus types (HPV 16, 18, 31, 45, 52, 58 and bovine papillomavirus type 1. Preparation of 384 well assay plates with serially diluted sera and the actual cell-based assay are separated in time, therefore batches of up to one hundred assay plates can be processed sequentially. A mean coefficient of variation (CV of 13% was obtained for anti-HPV 16 and HPV 18 titers for a standard serum tested in a total of 58 repeats on individual plates in seven independent runs. Natural antibody response was analyzed in 35 sera from patients with HPV 16 DNA positive cervical intraepithelial neoplasia grade 2+ lesions. The new HT-PBNA is based on Gaussia luciferase with increased sensitivity compared to the previously described manual PBNA (manPBNA based on secreted alkaline phosphatase as reporter. Titers obtained with HT-PBNA were generally higher than titers obtained with the manPBNA. A good linear correlation (R(2 = 0.7 was found between HT-PBNA titers and anti-HPV 16 L1 antibody-levels determined by a Luminex bead-based GST-capture assay for these 35 sera and a Kappa-value of 0.72, with only 3 discordant sera in the low titer range. In addition to natural low titer antibody responses the high sensitivity of the HT-PBNA also allows detection of cross-neutralizing antibodies induced by commercial HPV L1-vaccines and experimental L2-vaccines. When analyzing the WHO international standards for HPV 16 and 18 we determined an analytical sensitivity of 0.864 and 1.105 mIU, respectively.

  20. Amino acid and glucose metabolism in fed-batch CHO cell culture affects antibody production and glycosylation

    DEFF Research Database (Denmark)

    Fan, Yuzhou; Jimenez Del Val, Ioscani; Müller, Christian

    2015-01-01

    Fed-batch Chinese hamster ovary (CHO) cell culture is the most commonly used process for IgG production in the biopharmaceutical industry. Amino acid and glucose consumption, cell growth, metabolism, antibody titer, and N-glycosylation patterns are always the major concerns during upstream process...

  1. Neutralizing Antibody Responses to Antigenically Drifted Influenza A(H3N2) Viruses among Children and Adolescents following 2014-2015 Inactivated and Live Attenuated Influenza Vaccination

    Science.gov (United States)

    Martin, Judith M.; Gross, F. Liaini; Jefferson, Stacie; Cole, Kelly Stefano; Archibald, Crystal Ann; Nowalk, Mary Patricia; Susick, Michael; Moehling, Krissy; Spencer, Sarah; Chung, Jessie R.; Flannery, Brendan; Zimmerman, Richard K.

    2016-01-01

    Human influenza A(H3N2) viruses that predominated during the moderately severe 2014-2015 influenza season differed antigenically from the vaccine component, resulting in reduced vaccine effectiveness (VE). To examine antibody responses to 2014-2015 inactivated influenza vaccine (IIV) and live-attenuated influenza vaccine (LAIV) among children and adolescents, we collected sera before and after vaccination from 150 children aged 3 to 17 years enrolled at health care facilities. Hemagglutination inhibition (HI) assays were used to assess the antibody responses to vaccine strains. We evaluated cross-reactive antibody responses against two representative A(H3N2) viruses that had antigenically drifted from the A(H3N2) vaccine component using microneutralization (MN) assays. Postvaccination antibody titers to drifted A(H3N2) viruses were higher following receipt of IIV (MN geometric mean titers [GMTs], 63 to 68; 38 to 45% achieved seroconversion) versus LAIV (MN GMT, 22; only 3 to 5% achieved seroconversion). In 9- to 17-year-olds, the highest MN titers were observed among IIV-vaccinated individuals who had received LAIV in the previous season. Among all IIV recipients aged 3 to 17 years, the strongest predictor of antibody responses to the drifted viruses was the prevaccination titers to the vaccine strain. The results of our study suggest that in an antigenically drifted influenza season, vaccination still induced cross-reactive antibody responses to drifted circulating A(H3N2) viruses, although higher antibody titers may be required for protection. Antibody responses to drifted A(H3N2) viruses following vaccination were influenced by multiple factors, including vaccine type and preexisting immunity from prior exposure. PMID:27558294

  2. Synthesis and biology of cyclic imine toxins, an emerging class of potent, globally distributed marine toxins.

    Science.gov (United States)

    Stivala, Craig E; Benoit, Evelyne; Aráoz, Rómulo; Servent, Denis; Novikov, Alexei; Molgó, Jordi; Zakarian, Armen

    2015-03-01

    From a small group of exotic compounds isolated only two decades ago, Cyclic Imine (CI) toxins have become a major class of marine toxins with global distribution. Their distinct chemical structure, biological mechanism of action, and intricate chemistry ensures that CI toxins will continue to be the subject of fascinating fundamental studies in the broad fields of chemistry, chemical biology, and toxicology. The worldwide occurrence of potent CI toxins in marine en