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John C Herr - One of the best experts on this subject based on the ideXlab platform.
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Update on Sperm Antigen-based contraceptive vaccines
Immunology and Allergy Clinics of North America, 2002Co-Authors: John C HerrAbstract:No contraceptive vaccine has reached the market for human use, including vaccines based on Antigens derived from Sperm, eggs, reproductive hormones, or the early conceptus. To catalog all the contraceptive targets that have been proposed or to discuss Sperm vaccinogens in detail is beyond the scope of this article. A brief history of Sperm-Antigen immunocontraception is presented, the rationale for proceeding with a Sperm vaccine is summarized, several prominent Sperm immunogens are noted, and the challenges of creating a safe and effective Sperm-based vaccine for women are discussed. Strategies in proteomics and genomics that promise to accelerate the pace of contraceptive vaccine target discovery are emphasized. Particular attention is directed to clinical issues that are related to the eventual applicability of a contraceptive vaccine and to questions that may serve as departure points that stimulate further research. There is skepticism about whether vaccination with Sperm Antigens remains a viable contraceptive strategy after the emergence of combinatorial chemistry, drug modeling, and small molecule inhibitors. These trends in pharmaceutical science undoubtedly will lead to contraceptive drug candidates as a wealth of new proteins, associated specifically with reproductive tissues, are mined from the human genome to provide targets for rational drug design. It is questionable whether immunocontraceptive strategies should be pursued when combinatorial chemistry and small molecule inhibitors seem so promising in contraceptive development. This author is convinced that the rationale for immunocontraception remains strong. The search for contraceptive drug targets and contraceptive immunogens share several common features. Proteome-based strategies for identifying protein targets for contraceptive vaccine develop
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Anti-Sperm antibodies from infertile patients and their cognate Sperm Antigens: a review. Identity between SAGA-1, the H6-3C4 Antigen, and CD52.
American journal of reproductive immunology (New York N.Y. : 1989), 2000Co-Authors: Alan B. Diekman, Kenneth L Klotz, Norton Elizabeth, V A Westbrook, S Naaby-hansen, John C HerrAbstract:PROBLEM: The correlation of anti-Sperm antibodies (ASA) with some instances of unexplained infertility implicates a role for these antibodies in blocking fertilization. Improved diagnosis and treatment of immunologic infertility, as well as a more complete understanding of the mechanism behind this phenomenon, are dependent on the identification and characterization of relevant Sperm Antigens. METHOD OF STUDY: In this article, we review literature on methods employed to identify Sperm Antigens using anti-Sperm polyclonal and monoclonal antibodies from infertile patients and vasectomized men. Particular focus is given to approaches using human and mouse monoclonal antibodies to define the SAGA-1 human Sperm Antigen. RESULTS: ASA present in sera and genital tract secretions from infertile patients and vasectomized men have been employed in a variety of methods to identify Sperm Antigens. In an alternate approach, a monoclonal antibody (mAb), H6-3C4, was immortalized from the lymphocytes of an infertile woman who exhibited Sperm-immobilizing titers. Subsequently, the Sperm-agglutinating, murine S19 mAb was shown to react with the H6-3C4 cognate Antigen. The H6-3C4/S19 cognate Antigen, designated Sperm Agglutination Antigen-1 (SAGA-1), was characterized as a polymorphic, highly acidic, GPI-anchored glycoprotein on the surface of human Spermatozoa. Purification with the S19 mAb followed by microsequencing demonstrated that the SAGA-1 core peptide is identical to CD52, a glycoprotein on the surface of human lymphocytes. Immunoblot analysis demonstrated that these two glycoproteins differed in carbohydrate composition. Thus, Sperm SAGA-1 and lymphocyte CD52 represent glycoforms, glycoproteins with the same core peptide but with different carbohydrate structures. CONCLUSIONS: Autoimmunity to the SAGA-1 and/or CD52 glycoforms may lead to infertility. Structural and immunologic differences between these glycoproteins may be important factors in the etiology of immunologic infertility and other autoimmune disorders.
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oviductal antibody response to a defined recombinant Sperm Antigen in macaques
Biology of Reproduction, 1997Co-Authors: Barbara E Kurth, Clifford Weston, Prabhakara P Reddi, Donald Bryant, Renuka Bhattacharya, Charles J Flickinger, John C HerrAbstract:Macaque oviductal fluids were assayed for specific antibodies to the intra-acrosomal Sperm protein SP-10 after immunizations with recombinant macaque SP-10 (re-mqSP-10), a candidate contraceptive vaccinogen. Access ports, consisting of a subcutaneous collecting reservoir and a catheter to cannulate the oviduct, were implanted into monkeys for repeated aspiration of oviductal fluid. Monkeys were inoculated i.m. once a month with an emulsion consisting of 2 mg re-mqSP-10 in a vehicle of squalene and mannin monooleate. Oviductal fluids and serum were collected during the periovulatory period for six menstrual cycles, and IgG and IgA Antigen-specific antibodies in preimmune and immune fluids were compared by ELISA. Both relative and absolute concentrations of SP-10-specific immunoglobulins (Ig) were determined. Oviductal fluids from immunized animals showed significant increases in anti-SP-10 IgG at cycle 2 and at all subsequent intervals. Anti-SP-10 IgA significantly increased in oviductal fluid at cycles 4, 5, and 6. Serum anti-SP-10 IgG increased at cycle 2 and remained significantly elevated through cycle 6, while serum anti-SP-10 IgA was higher than in preimmune samples at cycle 4. Serum antibodies generated to the recombinant SP-10 recognized SP-10 extracted from macaque Sperm on Western blots. Immunocytochemical staining of macaque and human Sperm showed acrosomal immunofluorescence with both immune oviductal fluids and serum using both anti-lgG and anti-lgA secondary antibodies. This study demonstrates for the first time 1) IgG and IgA antibodies to a defined recombinant Sperm-specific Antigen in primate oviductal fluids after systemic immunization and 2) the recognition by primate oviductal fluid IgG and IgA of the endogenous contraceptive target on both human and macaque Sperm.
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purification and characterization of a Sperm Antigen recognized by hsa 5 monoclonal antibody
Journal of Reproductive Immunology, 1995Co-Authors: Tatsuhiro Yoshiki, John C Herr, Chiyu Gregory LeeAbstract:Among the monoclonal antibodies generated against acrosome-reacted human Sperm, HSA-5 was shown to react with a Sperm Antigen localized predominantly to the equatorial region of the acrosome of human Sperm and to the head and tail of mouse Sperm. This antibody reacted with the methanol-fixed Sperm, but not with fresh live Sperm. When purified by immunoaffinity column, a major protein band with a molecular mass of approximately 100 kDa on SDS gel was isolated from fresh human Sperm extract. The immunospecificity of isolated human Sperm protein to this monoclonal antibody was verified by enzyme-linked immunosorbent assay and Western blot analysis. This Antigen, designated as HSA-5, was susceptible to proteolytic degradation and revealed multiple immunoreactive bands in Western blot analyses of some preparations. Mouse Sperm homogenates showed a similar polymorphic pattern to that of human samples. The tissue specificity of this Antigen was examined immunohistochemically using various mouse and human tissues. HSA-5 did not cross-react with any other tissues except for Sperm in adult testes and epididymis. This antibody also showed no binding activity to testicular tissue sections from mice of 13 and 21 days of age. The results of our study suggest that the Sperm Antigen recognized by HSA-5 monoclonal antibody is a differentiation Antigen, which is expressed postmeiotically in testicular Sperm but not in any somatic tissues.
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epitope analysis of a Sperm acrosomal Antigen defined by hsa 5 monoclonal antibody
Journal of Reproductive Immunology, 1995Co-Authors: Chiyu Gregory Lee, Tatsuhiro Yoshiki, John C Herr, Leo Chui, Patricia Mcchesney, Eung Soo Hwang, Engshang HuangAbstract:Among the monoclonal antibodies recommended by the WHO Sperm Antigen Workshop for immunocontraceptive vaccine development, HSA-5 showed a high degree of Sperm specificity and significantly inhibited in vitro fertilization in both humans and mice. Using a Western blot assay, HSA-5 was found to recognize a Sperm Antigen designated as HSAg-5 (human) or MSAg-5 (mouse) which ranged in molecular weight from 18 to 100 kDa. This monoclonal antibody was used as the probe for the immunoscreening of mouse testis cDNA libraries constructed in the lambda gt-11 expression vector. One of the positive cDNA clones was shown to have a cDNA insert of approximately 1 kb and to encode a recombinant fusion protein containing 77 amino acid residues in the C-terminal region of MSAg-5. This 1 kb cDNA insert was engineered in a pGEX vector to express a recombinant glutathione S-transferase fusion protein (GST-5). Using an enzyme-linked immunosorbent assay (ELISA) and Western blot analysis, both anti-GST-5 sera and the monoclonal antibody were shown to react with GST-5. The Northern blot of a mouse testis RNA preparation revealed that the isolated cDNA probe hybridized with a 4.0 kb mRNA. Several oligopeptides were synthesized based on the predicted C-terminal hydrophilic regions of the recombinant fusion protein. Using ELISA and a dot blot assay, peptide regions containing the immunogenic epitopes recognized by HSA-5 monoclonal antibody were identified.
Shohei Koide - One of the best experts on this subject based on the ideXlab platform.
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Identification of the Sperm Antigen interacting with antibodies in serum from an infertile woman.
Andrologia, 2009Co-Authors: Tatsuji Haneji, Shohei KoideAbstract:Serum (IS) obtained from an infertile woman induced head-to-head agglutination of human Sperm. The immunoglobulin G (IgG) fraction of the IS was prepared by ammonium sulfate fractionation and DEAE cellulose chromatography. The IgG localized to the post-acrosomal region of the Sperm, determined by indirect immunofluorescence and interacted with a human Sperm protein with an estimated Mr of 80 kDa, determined by immunoblotting. The identity of the interacting Sperm Antigen was verified by isolating the 80 kDa Sperm protein by affinity chromatography. The present results suggest that the anti-80 kDa antibodies may be responsible for the infertility.
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Studies with Synthetic Peptides of 80 kDa Human Sperm Antigen (80 kDa HSA).
American journal of reproductive immunology (New York N.Y. : 1989), 2004Co-Authors: Vandana Vernekar, Atmaram H. Bandivdekar, Vijaya P. Raghavan, Masaharu Kamada, Shohei KoideAbstract:Problem: The 80 kDa human Sperm Antigen (HSA) is a Sperm-specific and conserved Antigen, capable of inducing immunological infertility. Partial N-terminal amino acid sequences of 80 kDa HSA (Peptide NT) and its peptides obtained by digestion with endoproteinase Lys-C (peptides 1–4) and endoproteinase Glu-C (peptides 5–6) did not show any sequence homology with reported known proteins deposited in the Gen-Bank. These sequenced peptides were synthesized and conjugated to key hole limpet haemocyanin (KLH) and evaluated for its antifertility effects. The present communication describes the characterization of these peptides and their antibodies. Method of study: Peptides NT, 1, 2, 3 and 4 were synthesized and conjugated to KLH. Antibodies to KLH conjugated peptides were raised in rabbits by active immunization and the antibody titer was determined by enzyme-linked immunosorbent assay (ELISA) using Sperm extract coated wells. The binding specificity of the synthetic peptides or purified 80 kDa HSA to their antibodies was assessed in the presence of various doses of respective synthetic peptides or 80 kDa HSA. The binding specificity was further confirmed by Western blot analysis. Antipeptide antibodies were also checked for Sperm agglutinating activity, in-vitro. Results: Active immunization of rabbits elicited significant antibody titers against the synthetic peptides, except for peptide 3. Antipeptide antibodies specifically recognized the native protein in an ELISA and induced in-vitro agglutination of human, rat and monkey Sperm. In addition, Western blot analysis showed that these antipeptide antibodies specifically bind to the 80 kDa HSA band of the Sperm extract. Conclusion: Synthetic peptides of 80 kDa HSA are immunogenic and antibodies raised against these peptides recognize the native protein detected by ELISA, Western blot analysis. In addition, they possess Sperm agglutinating activity. These findings suggest that they are promising candidates in the development of immunocontraceptives.
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Characterization of 80 kDa human Sperm Antigen responsible for immunoinfertility.
American journal of reproductive immunology (New York N.Y. : 1989), 2001Co-Authors: Atmaram H. Bandivdekar, Vandana Vernekar, S. B. Moodbidri, Shohei KoideAbstract:PROBLEM: An 80 kDa human Sperm Antigen (80 kDa HSA) has been identified by western blot technique using serum of an immunoinfertile woman as a probe. The 80 kDa HSA has been subsequently purified from Sperm extract and investigated for antifertility effects. METHOD OF STUDY: The purified 80 kDa HSA was used to immunize adult male and female rats. Rabbit anti 80 kDa HSA antibodies were used for immunofluorescent and immunohistochemical staining to demonstrate the presence of 80 kDa HSA on the Sperm and to investigate its tissue distribution. The N-terminal sequence of native 80 kDa HSA and the peptides obtained by its endoproteinase Lys-C was determined. RESULTS: Active immunization of male and female rats with 80 kDa HSA caused infertility in all the immunized animals. Immunofluorescent staining showed its localization on the head region of the human and rat Spermatozoa. While immunohistochemical studies showed its localization in the testes and epididymis but not in other somatic tissues. Partial amino-acid sequence analysis showed no sequence homology with any of the known protein in the database. CONCLUSIONS: 80 kDa HSA is a promising candidate Antigen for immunocontraception as it is characterized and found to cause infertility upon active immunization, specific to Spermatozoa and is conserved.
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PARTIAL AMINO ACID SEQUENCING OF 80-kDa HUMAN Sperm Antigen (80-kDa HSA)
Archives of andrology, 2001Co-Authors: Atmaram H. Bandivdekar, Shohei Koide, Vandana Vernekar, D. Mruk, C. Y. Cheng, S. B. MoodbidriAbstract:An 80-kDa human Sperm Antigen (80-kDa HSA) has been identified as a Sperm protein responsible for inducing immunoinfertility. Immunization with the purified protein induced infertility in male and female rats. Immunohistochemical and immunofluorescent studies have demonstrated that the Antigen is specific to Spermatozoa. The present study describes the partial amino acid sequencing of 80-kDa HSA. The homogeneous protein was electrophoretically transferred onto a PVDF membrane and the excised band of 80-kDa HSA was used to determine the partial N-terminal amino acid sequence. The protein was then subjected to enzymatic digestion with endoproteinase Lys-C and endoproteinase Glu-C. The partial amino acid sequence of the major peptides thus obtained was determined. The digestion with endoproteinase Lys-C generated 4 major peptides, two of which showed partial sequence homology with lactoferrin. Endoproteinase Glu-C digestion produced 3 major peptides. The sequences of the 2 peptides were determined for which ...
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Specific cytotoxicity of antibody to YAL-198, a Sperm Antigen peptide, to murine zygote.
Archives of andrology, 2001Co-Authors: Masaharu Kamada, Masaya Takikawa, Masahiko Maegawa, Satoshi Yamamoto, S. Yamano, Minoru Irahara, T. Aono, Shiroh Futaki, Yasukazu Ohmoto, Shohei KoideAbstract:Active immunization with the peptide segments rSMP-230 and YAL-198, corresponding to the hydrophilic extracellular domain of two human Sperm Antigens (rSMP-B and YWK-II, respectively), reduced fertility in female rats by different mechanisms. The anti-rSMP-230 antibody interferes with human and murine fertilization, and the anti-YAL-198 antibody blocks the development of mouse embryos. The authors examined in vitro at which stage the antibodies to rSMP-230 and YAL-198 were cytotoxic to murine embryos up to morula/blastocyst stage. Anti-rSMP-230 antibody was not cytotoxic to any stages. On the other hand, the anti-YAL-198 antibody arrested the growth of embryos at the 2-cell stage but not at more advanced developmental stages. When the anti-YAL-198 antibody was used, spotty staining was observed only on the surfaces of embryos that had arrested at the 2-cell stage. Unstained embryos, however, continued to develop normally. In contrast, the anti-rSMP-230 antibody stained murine Sperm but failed to stain murine ova and embryos. The present results suggest that the human Sperm components rSMP-B and YWK-II play important roles in Sperm-egg interaction and early development of the embryo, respectively.
Atmaram H. Bandivdekar - One of the best experts on this subject based on the ideXlab platform.
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Studies on the expression of 80-kDa human Sperm Antigen in rat testis and epididymis.
The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society, 2007Co-Authors: Bharati Gangaram Khobarekar, Vandana Vernekar, Esakki Prabagaran, Vijaya P. Raghavan, Atmaram H. BandivdekarAbstract:The 80-kDa human Sperm Antigen (HSA) has demonstrated to be a promising candidate for development of an antifertility vaccine because it is a Sperm-specific, conserved, and immunogenic protein. The present study demonstrates the androgen-regulated expression of 80-kDa HSA in testis and epididymis of rat by immunohistochemistry (IHC), using its specific antibodies. Developmental expression of 80-kDa HSA was investigated on days 10, 20, 40, 60, and 90 of age in the testis and epididymis by IHC, and relative staining intensity was estimated by image analysis using BIOVIS software. On days 10 and 20, no significant staining was observed in the testis and epididymis, whereas it gradually increased from day 40 onwards. The highest staining was seen on day 90 in both testis and epididymis. Gradual increase in expression of 80-kDa HSA after day 40 suggests that it is possibly regulated by androgen. To study the androgen-regulated expression of 80-kDa, adult male rats were treated with 75 mg/kg body weight of ethy...
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Antifertility effect of passive administration of antibodies to 80kDa human Sperm Antigen and its synthetic peptides in male and female rats
American journal of reproductive immunology (New York N.Y. : 1989), 2005Co-Authors: Atmaram H. Bandivdekar, Vandana Vernekar, Masaharu Kamada, Vijaya P. RaghavanAbstract:Problem A human Sperm Antigen of molecular size of about 80kDa (80kDa HSA) has been reported to be Sperm-specific, conserved and responsible for inducing immunological infertility. The partial N-terminal amino acid sequence of 80kDa HSA (peptide NT) and its peptides obtained by enzymatic digestion with endoproteinase Lys-C (peptides 1–4) and with endoproteinase Glu-C (peptides 5 and 6) did not show sequence homology with any of the proteins of the GenBank. The peptides NT, 1, 2, 3 and 4 were synthesized, conjugated to keyhole limpet hemocyanin and used as an immunogen to raise the antibodies in rabbits. Peptide 3 did not elicit significant antibody titer while peptides NT, 1, 2 and 4 elicited significant antibody titer and immunobiologically mimicked the native protein. Method of study Effects of passive administration of two injections each of 200 μL of antibodies or 10 and 40 μg purified immunoglobulins to 80kDa HSA, peptides NT, 1, 2 and 4 on fertility in male and female rats were investigated. Results Passive administration of antibodies to 80kDa HSA and its peptides NT, 1, 2 and 4 resulted in agglutination of epididymal Spermatozoa with loss of motility but had no effect on Sperm count or weights of the reproductive organs. These animals failed to impregnate normal female rats. Passive administration of these antibodies to female rats also resulted in infertility. The presence of antibodies was detected by enzyme-linked immunosorbent assay in uterine secretions of animals treated with antipeptide antibody. The presence of agglutinated Spermatozoa was observed in the post-coital vaginal smears of these animals. The immunized females were found to be ovulating normally and the number of corpora lutea were unaltered. Of the four antipeptide antibodies studied, antibodies to peptides NT and 1 were most effective in inhibiting fertility both in male as well as female rats. Hence, the antifertility studies were further confirmed by passive administration of 10 and 40 μg of purified immunoglobulins of antibodies to NT and 1, which resulted in a dose-dependent inhibition of fertility in male and female rats. Conclusions The study demonstrated that the synthetic peptides of 80kDa HSA immunobiologically mimicked the native protein and impaired fertility following passive administration of antipeptide antibodies and hence, suggested the suitability of synthetic peptides of 80kDa HSA as candidates for development of antifertility vaccine.
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Studies with Synthetic Peptides of 80 kDa Human Sperm Antigen (80 kDa HSA).
American journal of reproductive immunology (New York N.Y. : 1989), 2004Co-Authors: Vandana Vernekar, Atmaram H. Bandivdekar, Vijaya P. Raghavan, Masaharu Kamada, Shohei KoideAbstract:Problem: The 80 kDa human Sperm Antigen (HSA) is a Sperm-specific and conserved Antigen, capable of inducing immunological infertility. Partial N-terminal amino acid sequences of 80 kDa HSA (Peptide NT) and its peptides obtained by digestion with endoproteinase Lys-C (peptides 1–4) and endoproteinase Glu-C (peptides 5–6) did not show any sequence homology with reported known proteins deposited in the Gen-Bank. These sequenced peptides were synthesized and conjugated to key hole limpet haemocyanin (KLH) and evaluated for its antifertility effects. The present communication describes the characterization of these peptides and their antibodies. Method of study: Peptides NT, 1, 2, 3 and 4 were synthesized and conjugated to KLH. Antibodies to KLH conjugated peptides were raised in rabbits by active immunization and the antibody titer was determined by enzyme-linked immunosorbent assay (ELISA) using Sperm extract coated wells. The binding specificity of the synthetic peptides or purified 80 kDa HSA to their antibodies was assessed in the presence of various doses of respective synthetic peptides or 80 kDa HSA. The binding specificity was further confirmed by Western blot analysis. Antipeptide antibodies were also checked for Sperm agglutinating activity, in-vitro. Results: Active immunization of rabbits elicited significant antibody titers against the synthetic peptides, except for peptide 3. Antipeptide antibodies specifically recognized the native protein in an ELISA and induced in-vitro agglutination of human, rat and monkey Sperm. In addition, Western blot analysis showed that these antipeptide antibodies specifically bind to the 80 kDa HSA band of the Sperm extract. Conclusion: Synthetic peptides of 80 kDa HSA are immunogenic and antibodies raised against these peptides recognize the native protein detected by ELISA, Western blot analysis. In addition, they possess Sperm agglutinating activity. These findings suggest that they are promising candidates in the development of immunocontraceptives.
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Characterization of 80 kDa human Sperm Antigen responsible for immunoinfertility.
American journal of reproductive immunology (New York N.Y. : 1989), 2001Co-Authors: Atmaram H. Bandivdekar, Vandana Vernekar, S. B. Moodbidri, Shohei KoideAbstract:PROBLEM: An 80 kDa human Sperm Antigen (80 kDa HSA) has been identified by western blot technique using serum of an immunoinfertile woman as a probe. The 80 kDa HSA has been subsequently purified from Sperm extract and investigated for antifertility effects. METHOD OF STUDY: The purified 80 kDa HSA was used to immunize adult male and female rats. Rabbit anti 80 kDa HSA antibodies were used for immunofluorescent and immunohistochemical staining to demonstrate the presence of 80 kDa HSA on the Sperm and to investigate its tissue distribution. The N-terminal sequence of native 80 kDa HSA and the peptides obtained by its endoproteinase Lys-C was determined. RESULTS: Active immunization of male and female rats with 80 kDa HSA caused infertility in all the immunized animals. Immunofluorescent staining showed its localization on the head region of the human and rat Spermatozoa. While immunohistochemical studies showed its localization in the testes and epididymis but not in other somatic tissues. Partial amino-acid sequence analysis showed no sequence homology with any of the known protein in the database. CONCLUSIONS: 80 kDa HSA is a promising candidate Antigen for immunocontraception as it is characterized and found to cause infertility upon active immunization, specific to Spermatozoa and is conserved.
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PARTIAL AMINO ACID SEQUENCING OF 80-kDa HUMAN Sperm Antigen (80-kDa HSA)
Archives of andrology, 2001Co-Authors: Atmaram H. Bandivdekar, Shohei Koide, Vandana Vernekar, D. Mruk, C. Y. Cheng, S. B. MoodbidriAbstract:An 80-kDa human Sperm Antigen (80-kDa HSA) has been identified as a Sperm protein responsible for inducing immunoinfertility. Immunization with the purified protein induced infertility in male and female rats. Immunohistochemical and immunofluorescent studies have demonstrated that the Antigen is specific to Spermatozoa. The present study describes the partial amino acid sequencing of 80-kDa HSA. The homogeneous protein was electrophoretically transferred onto a PVDF membrane and the excised band of 80-kDa HSA was used to determine the partial N-terminal amino acid sequence. The protein was then subjected to enzymatic digestion with endoproteinase Lys-C and endoproteinase Glu-C. The partial amino acid sequence of the major peptides thus obtained was determined. The digestion with endoproteinase Lys-C generated 4 major peptides, two of which showed partial sequence homology with lactoferrin. Endoproteinase Glu-C digestion produced 3 major peptides. The sequences of the 2 peptides were determined for which ...
Vandana Vernekar - One of the best experts on this subject based on the ideXlab platform.
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evaluation of the potential of synthetic peptides of 80 kda human Sperm Antigen 80 kdahsa for the development of contraceptive vaccine for male
Vaccine, 2008Co-Authors: Bharati Gangaram Khobarekar, Vandana Vernekar, Vijaya P. Raghavan, Masaharu Kamada, Masahiko Maegawa, A H BandivdekarAbstract:80 kDaHSA has been demonstrated to be responsible for inducing immunoinfertility. Synthetic peptides NT, 1, 2 and 4 of 80 kDaHSA are immunogenic and immunobiologically mimic the native protein. Peptides 1 and NT being highly immunogenic their potential for contraceptive vaccine development was evaluated. Active immunization of male rabbits with peptide-1 and -NT induced reversible infertility in 100% and 60% of animals, respectively and subsequently active immunization of non-human primate model, male marmosets with peptide-1 induced reversible infertility in six out of seven high antibody titer animals. The present study suggests the potential of peptide-1 of 80 kDaHSA for the development of contraceptive vaccine.
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Studies on the expression of 80-kDa human Sperm Antigen in rat testis and epididymis.
The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society, 2007Co-Authors: Bharati Gangaram Khobarekar, Vandana Vernekar, Esakki Prabagaran, Vijaya P. Raghavan, Atmaram H. BandivdekarAbstract:The 80-kDa human Sperm Antigen (HSA) has demonstrated to be a promising candidate for development of an antifertility vaccine because it is a Sperm-specific, conserved, and immunogenic protein. The present study demonstrates the androgen-regulated expression of 80-kDa HSA in testis and epididymis of rat by immunohistochemistry (IHC), using its specific antibodies. Developmental expression of 80-kDa HSA was investigated on days 10, 20, 40, 60, and 90 of age in the testis and epididymis by IHC, and relative staining intensity was estimated by image analysis using BIOVIS software. On days 10 and 20, no significant staining was observed in the testis and epididymis, whereas it gradually increased from day 40 onwards. The highest staining was seen on day 90 in both testis and epididymis. Gradual increase in expression of 80-kDa HSA after day 40 suggests that it is possibly regulated by androgen. To study the androgen-regulated expression of 80-kDa, adult male rats were treated with 75 mg/kg body weight of ethy...
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Antifertility effect of passive administration of antibodies to 80kDa human Sperm Antigen and its synthetic peptides in male and female rats
American journal of reproductive immunology (New York N.Y. : 1989), 2005Co-Authors: Atmaram H. Bandivdekar, Vandana Vernekar, Masaharu Kamada, Vijaya P. RaghavanAbstract:Problem A human Sperm Antigen of molecular size of about 80kDa (80kDa HSA) has been reported to be Sperm-specific, conserved and responsible for inducing immunological infertility. The partial N-terminal amino acid sequence of 80kDa HSA (peptide NT) and its peptides obtained by enzymatic digestion with endoproteinase Lys-C (peptides 1–4) and with endoproteinase Glu-C (peptides 5 and 6) did not show sequence homology with any of the proteins of the GenBank. The peptides NT, 1, 2, 3 and 4 were synthesized, conjugated to keyhole limpet hemocyanin and used as an immunogen to raise the antibodies in rabbits. Peptide 3 did not elicit significant antibody titer while peptides NT, 1, 2 and 4 elicited significant antibody titer and immunobiologically mimicked the native protein. Method of study Effects of passive administration of two injections each of 200 μL of antibodies or 10 and 40 μg purified immunoglobulins to 80kDa HSA, peptides NT, 1, 2 and 4 on fertility in male and female rats were investigated. Results Passive administration of antibodies to 80kDa HSA and its peptides NT, 1, 2 and 4 resulted in agglutination of epididymal Spermatozoa with loss of motility but had no effect on Sperm count or weights of the reproductive organs. These animals failed to impregnate normal female rats. Passive administration of these antibodies to female rats also resulted in infertility. The presence of antibodies was detected by enzyme-linked immunosorbent assay in uterine secretions of animals treated with antipeptide antibody. The presence of agglutinated Spermatozoa was observed in the post-coital vaginal smears of these animals. The immunized females were found to be ovulating normally and the number of corpora lutea were unaltered. Of the four antipeptide antibodies studied, antibodies to peptides NT and 1 were most effective in inhibiting fertility both in male as well as female rats. Hence, the antifertility studies were further confirmed by passive administration of 10 and 40 μg of purified immunoglobulins of antibodies to NT and 1, which resulted in a dose-dependent inhibition of fertility in male and female rats. Conclusions The study demonstrated that the synthetic peptides of 80kDa HSA immunobiologically mimicked the native protein and impaired fertility following passive administration of antipeptide antibodies and hence, suggested the suitability of synthetic peptides of 80kDa HSA as candidates for development of antifertility vaccine.
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Studies with Synthetic Peptides of 80 kDa Human Sperm Antigen (80 kDa HSA).
American journal of reproductive immunology (New York N.Y. : 1989), 2004Co-Authors: Vandana Vernekar, Atmaram H. Bandivdekar, Vijaya P. Raghavan, Masaharu Kamada, Shohei KoideAbstract:Problem: The 80 kDa human Sperm Antigen (HSA) is a Sperm-specific and conserved Antigen, capable of inducing immunological infertility. Partial N-terminal amino acid sequences of 80 kDa HSA (Peptide NT) and its peptides obtained by digestion with endoproteinase Lys-C (peptides 1–4) and endoproteinase Glu-C (peptides 5–6) did not show any sequence homology with reported known proteins deposited in the Gen-Bank. These sequenced peptides were synthesized and conjugated to key hole limpet haemocyanin (KLH) and evaluated for its antifertility effects. The present communication describes the characterization of these peptides and their antibodies. Method of study: Peptides NT, 1, 2, 3 and 4 were synthesized and conjugated to KLH. Antibodies to KLH conjugated peptides were raised in rabbits by active immunization and the antibody titer was determined by enzyme-linked immunosorbent assay (ELISA) using Sperm extract coated wells. The binding specificity of the synthetic peptides or purified 80 kDa HSA to their antibodies was assessed in the presence of various doses of respective synthetic peptides or 80 kDa HSA. The binding specificity was further confirmed by Western blot analysis. Antipeptide antibodies were also checked for Sperm agglutinating activity, in-vitro. Results: Active immunization of rabbits elicited significant antibody titers against the synthetic peptides, except for peptide 3. Antipeptide antibodies specifically recognized the native protein in an ELISA and induced in-vitro agglutination of human, rat and monkey Sperm. In addition, Western blot analysis showed that these antipeptide antibodies specifically bind to the 80 kDa HSA band of the Sperm extract. Conclusion: Synthetic peptides of 80 kDa HSA are immunogenic and antibodies raised against these peptides recognize the native protein detected by ELISA, Western blot analysis. In addition, they possess Sperm agglutinating activity. These findings suggest that they are promising candidates in the development of immunocontraceptives.
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Characterization of 80 kDa human Sperm Antigen responsible for immunoinfertility.
American journal of reproductive immunology (New York N.Y. : 1989), 2001Co-Authors: Atmaram H. Bandivdekar, Vandana Vernekar, S. B. Moodbidri, Shohei KoideAbstract:PROBLEM: An 80 kDa human Sperm Antigen (80 kDa HSA) has been identified by western blot technique using serum of an immunoinfertile woman as a probe. The 80 kDa HSA has been subsequently purified from Sperm extract and investigated for antifertility effects. METHOD OF STUDY: The purified 80 kDa HSA was used to immunize adult male and female rats. Rabbit anti 80 kDa HSA antibodies were used for immunofluorescent and immunohistochemical staining to demonstrate the presence of 80 kDa HSA on the Sperm and to investigate its tissue distribution. The N-terminal sequence of native 80 kDa HSA and the peptides obtained by its endoproteinase Lys-C was determined. RESULTS: Active immunization of male and female rats with 80 kDa HSA caused infertility in all the immunized animals. Immunofluorescent staining showed its localization on the head region of the human and rat Spermatozoa. While immunohistochemical studies showed its localization in the testes and epididymis but not in other somatic tissues. Partial amino-acid sequence analysis showed no sequence homology with any of the known protein in the database. CONCLUSIONS: 80 kDa HSA is a promising candidate Antigen for immunocontraception as it is characterized and found to cause infertility upon active immunization, specific to Spermatozoa and is conserved.
Vijaya P. Raghavan - One of the best experts on this subject based on the ideXlab platform.
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evaluation of the potential of synthetic peptides of 80 kda human Sperm Antigen 80 kdahsa for the development of contraceptive vaccine for male
Vaccine, 2008Co-Authors: Bharati Gangaram Khobarekar, Vandana Vernekar, Vijaya P. Raghavan, Masaharu Kamada, Masahiko Maegawa, A H BandivdekarAbstract:80 kDaHSA has been demonstrated to be responsible for inducing immunoinfertility. Synthetic peptides NT, 1, 2 and 4 of 80 kDaHSA are immunogenic and immunobiologically mimic the native protein. Peptides 1 and NT being highly immunogenic their potential for contraceptive vaccine development was evaluated. Active immunization of male rabbits with peptide-1 and -NT induced reversible infertility in 100% and 60% of animals, respectively and subsequently active immunization of non-human primate model, male marmosets with peptide-1 induced reversible infertility in six out of seven high antibody titer animals. The present study suggests the potential of peptide-1 of 80 kDaHSA for the development of contraceptive vaccine.
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Studies on the expression of 80-kDa human Sperm Antigen in rat testis and epididymis.
The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society, 2007Co-Authors: Bharati Gangaram Khobarekar, Vandana Vernekar, Esakki Prabagaran, Vijaya P. Raghavan, Atmaram H. BandivdekarAbstract:The 80-kDa human Sperm Antigen (HSA) has demonstrated to be a promising candidate for development of an antifertility vaccine because it is a Sperm-specific, conserved, and immunogenic protein. The present study demonstrates the androgen-regulated expression of 80-kDa HSA in testis and epididymis of rat by immunohistochemistry (IHC), using its specific antibodies. Developmental expression of 80-kDa HSA was investigated on days 10, 20, 40, 60, and 90 of age in the testis and epididymis by IHC, and relative staining intensity was estimated by image analysis using BIOVIS software. On days 10 and 20, no significant staining was observed in the testis and epididymis, whereas it gradually increased from day 40 onwards. The highest staining was seen on day 90 in both testis and epididymis. Gradual increase in expression of 80-kDa HSA after day 40 suggests that it is possibly regulated by androgen. To study the androgen-regulated expression of 80-kDa, adult male rats were treated with 75 mg/kg body weight of ethy...
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Antifertility effect of passive administration of antibodies to 80kDa human Sperm Antigen and its synthetic peptides in male and female rats
American journal of reproductive immunology (New York N.Y. : 1989), 2005Co-Authors: Atmaram H. Bandivdekar, Vandana Vernekar, Masaharu Kamada, Vijaya P. RaghavanAbstract:Problem A human Sperm Antigen of molecular size of about 80kDa (80kDa HSA) has been reported to be Sperm-specific, conserved and responsible for inducing immunological infertility. The partial N-terminal amino acid sequence of 80kDa HSA (peptide NT) and its peptides obtained by enzymatic digestion with endoproteinase Lys-C (peptides 1–4) and with endoproteinase Glu-C (peptides 5 and 6) did not show sequence homology with any of the proteins of the GenBank. The peptides NT, 1, 2, 3 and 4 were synthesized, conjugated to keyhole limpet hemocyanin and used as an immunogen to raise the antibodies in rabbits. Peptide 3 did not elicit significant antibody titer while peptides NT, 1, 2 and 4 elicited significant antibody titer and immunobiologically mimicked the native protein. Method of study Effects of passive administration of two injections each of 200 μL of antibodies or 10 and 40 μg purified immunoglobulins to 80kDa HSA, peptides NT, 1, 2 and 4 on fertility in male and female rats were investigated. Results Passive administration of antibodies to 80kDa HSA and its peptides NT, 1, 2 and 4 resulted in agglutination of epididymal Spermatozoa with loss of motility but had no effect on Sperm count or weights of the reproductive organs. These animals failed to impregnate normal female rats. Passive administration of these antibodies to female rats also resulted in infertility. The presence of antibodies was detected by enzyme-linked immunosorbent assay in uterine secretions of animals treated with antipeptide antibody. The presence of agglutinated Spermatozoa was observed in the post-coital vaginal smears of these animals. The immunized females were found to be ovulating normally and the number of corpora lutea were unaltered. Of the four antipeptide antibodies studied, antibodies to peptides NT and 1 were most effective in inhibiting fertility both in male as well as female rats. Hence, the antifertility studies were further confirmed by passive administration of 10 and 40 μg of purified immunoglobulins of antibodies to NT and 1, which resulted in a dose-dependent inhibition of fertility in male and female rats. Conclusions The study demonstrated that the synthetic peptides of 80kDa HSA immunobiologically mimicked the native protein and impaired fertility following passive administration of antipeptide antibodies and hence, suggested the suitability of synthetic peptides of 80kDa HSA as candidates for development of antifertility vaccine.
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Studies with Synthetic Peptides of 80 kDa Human Sperm Antigen (80 kDa HSA).
American journal of reproductive immunology (New York N.Y. : 1989), 2004Co-Authors: Vandana Vernekar, Atmaram H. Bandivdekar, Vijaya P. Raghavan, Masaharu Kamada, Shohei KoideAbstract:Problem: The 80 kDa human Sperm Antigen (HSA) is a Sperm-specific and conserved Antigen, capable of inducing immunological infertility. Partial N-terminal amino acid sequences of 80 kDa HSA (Peptide NT) and its peptides obtained by digestion with endoproteinase Lys-C (peptides 1–4) and endoproteinase Glu-C (peptides 5–6) did not show any sequence homology with reported known proteins deposited in the Gen-Bank. These sequenced peptides were synthesized and conjugated to key hole limpet haemocyanin (KLH) and evaluated for its antifertility effects. The present communication describes the characterization of these peptides and their antibodies. Method of study: Peptides NT, 1, 2, 3 and 4 were synthesized and conjugated to KLH. Antibodies to KLH conjugated peptides were raised in rabbits by active immunization and the antibody titer was determined by enzyme-linked immunosorbent assay (ELISA) using Sperm extract coated wells. The binding specificity of the synthetic peptides or purified 80 kDa HSA to their antibodies was assessed in the presence of various doses of respective synthetic peptides or 80 kDa HSA. The binding specificity was further confirmed by Western blot analysis. Antipeptide antibodies were also checked for Sperm agglutinating activity, in-vitro. Results: Active immunization of rabbits elicited significant antibody titers against the synthetic peptides, except for peptide 3. Antipeptide antibodies specifically recognized the native protein in an ELISA and induced in-vitro agglutination of human, rat and monkey Sperm. In addition, Western blot analysis showed that these antipeptide antibodies specifically bind to the 80 kDa HSA band of the Sperm extract. Conclusion: Synthetic peptides of 80 kDa HSA are immunogenic and antibodies raised against these peptides recognize the native protein detected by ELISA, Western blot analysis. In addition, they possess Sperm agglutinating activity. These findings suggest that they are promising candidates in the development of immunocontraceptives.