Vaginal Epithelium Transiently Harbours HIV-1 Facilitating Transmission.

Vaginal transmission accounts for majority of newly acquired HIV infections worldwide. Initial events that transpire post-viral binding to vaginal epithelium leading to productive infection in the female reproductive tract are not well elucidated. Here, we examined the interaction of HIV-1 with vaginal epithelial cells (VEC) using Vk2/E6E7, an established cell line exhibiting an HIV-binding receptor phenotype (CD4-CCR5-CD206+) similar to primary cells. We observed rapid viral sequestration, as a metabolically active process that was dose-dependent. Sequestered virus demonstrated monophasic decay after 6 hours with a half-life of 22.435 hours, though residual virus was detectable 48 hours' post-exposure. Viral uptake was not followed by successful reverse transcription and thus productive infection in VEC unlike activated PBMCs. Intraepithelial virus was infectious as evidenced by infection in trans of PHA-p stimulated PBMCs on co-culture. Trans-infection efficiency, however, deteriorated with time, concordant with viral retention kinetics, as peak levels of sequestered virus coincided with maximum viral output of co-cultivated PBMCs. Further, blocking lymphocyte receptor function-associated antigen 1 (LFA-1) expressed on PBMCs significantly inhibited trans-infection suggesting that cell-to-cell spread of HIV from epithelium to target cells was LFA-1 mediated. In addition to stimulated PBMCs, we also demonstrated infection in trans of FACS sorted CD4+ T lymphocyte subsets expressing co-receptors CCR5 and CXCR4. These included, for the first time, potentially gut homing CD4+ T cell subsets co-expressing integrin α4ß7 and CCR5. Our study thus delineates a hitherto unexplored role for the vaginal epithelium as a transient viral reservoir enabling infection of susceptible cell types.

Immunogenicity of virus-like Semliki Forest virus replicon particles expressing Indian HIV-1C gag, env and polRT genes.

Development of a vaccine targeting human immunodeficiency virus-1 subtype C (HIV-1C) is an important public health priority in regions with a high prevalence of the clade C virus. The present study demonstrates the immunogenicity of recombinant Semliki Forest virus (SFV)-based virus-like replicon particles (VRPs) expressing Indian HIV-1C env/gag/polRT genes. Immunization of mice with recombinant VRPs in a homologous prime-boost protocol, either individually or in combination, elicited significant antigen-specific IFN-γ T cell responses as detected by the ELISPOT assay. Additionally, Gag-specific TNF-α secreting CD8+ and CD4+ T cells and Env-specific IL-2 secreting T cells were also elicited by mice immunized with Gag and Env constructs, respectively, as estimated by intracellular cytokine staining assay. Moreover, an HIV Pol-specific TNF-α response was elicited in mice immunized with a combination of the three VRP constructs. Furthermore, HIV-1C Gag and Env-specific binding antibodies were elicited as verified by gp120 ELISA and p24 Gag ELISA, respectively. The immunogenicity of VRPs was found to be higher as compared to that of RNA replicons and VRPs may therefore be promising preventive and therapeutic candidate vaccines for the control and management of HIV/AIDS.

Current status of a unique vaccine preventing pregnancy.

The ability of a vaccine linking beta hCG to a carrier to generate antibodies against hCG, its reversibility and safety was established by Phase I clinical trials conducted in India, Finland, Sweden, Chile and Brazil. Employing a hetero-species dimer (beta hCG-αoLH) linked to tetanus toxoid further improved the immunogenicity of the vaccine. Phase II clinical trials showed that anti-hCG titres above 50 ng/ml prevented pregnancy of sexually active fertile women without derangement of ovulation and menstrual regularity. On decline of antibodies, women conceived again to give birth to normal progeny. A genetically engineered vaccine consisting of beta hCG linked to B subunit of heat labile enterotoxin of E. coli has been made. It is expressed as DNA as well as protein. Priming with DNA followed by protein version of the vaccine generates very high titres against hCG in mice. Extensive toxicology studies in 2 species of rodents, and marmosets have shown complete safety of the vaccine. The vaccine is cleared for Clinical trials by the National Review committee on Genetic Manipulation and Drugs Controller General of India.

Immunogenicity of Semliki Forest virus based self-amplifying RNA expressing Indian HIV-1C genes in mice.

Development of recombinant vaccines is considered as a promising approach to prevent transmission and eradication of HIV/AIDS. Candidate vaccines tested so far have shown poor to modest efficacy. Self-amplifying RNAs of positive strand alphaviruses are reported to be promising vectors for development of recombinant vaccines. This study describes the construction, in vitro expression and in vivo immunogenicity of recombinant RNA vaccines developed by individually cloning gag, env and polRT genes of primary HIV-1C Indian isolates using Semliki Forest virus (SFV) vector. HIV-1C specific T cell responses were detected in mice immunized with rSFV2gen/gag RNA by IFN-γ ELISPOT assay. Furthermore, using flow cytometry based intracellular cytokine staining (ICCS) assay HIV-1C specific IL-2 responses were detected in immunized mice that were mediated by both CD4(+) and CD8(+) T cells. Mice immunized with rSFV2gen/env RNA elicited HIV-1C Env-specific antibodies as detected by gp120 ELISA. The Env, Gag and Pol (RT) RNA constructs in combination elicited better HIV-1C Env-specific humoral responses compared to mice immunized with Env RNA alone. In conclusion, rSFV2gen RNA constructs encoding HIV-1C antigens elicited clear cell mediated and humoral immune responses in mice, thus demonstrating the potential of self-amplifying rSFV2gen RNA as a promising candidate for anti-HIV vaccine development.

Advances in development of a contraceptive vaccine against human chorionic gonadotropin.

INTRODUCTION: There is continuing need for contraceptives. According to World Health Organization, 210 million pregnancies occur each year, out of which some 80 million are unintended. A vaccine offering privacy and periodic intake would be an attractive proposition. AREAS COVERED: The article is a brief review of three vaccines developed against human chorionic gonadotropin (hCG) with progressively better attributes. Clinical trials have proven in more than one country the complete safety and reversibility of the anti-hCG vaccine(s) in women. Vaccination does not entail any disturbance in levels of reproductive tract hormones of the woman or any disturbance in menstrual regularity and bleeding profiles. Phase II clinical trials show the effective prevention of pregnancy in sexually active women of proven fertility. A recombinant vaccine amenable to industrial production has been developed; it induces substantially higher antibody titers in mice of four different genetic strains than those required to prevent pregnancy in women. Rigorous toxicology studies have been completed on this vaccine in rodents and marmosets. EXPERT OPINION: This unique vaccine, requiring periodic intake and demonstrating no impairment of ovulation, hormonal profiles and menstrual regularity, is on the verge of final clinical trials under the aegis of the Indian Council of Medical Research and should be a valuable addition to the available contraceptives.

Evaluation of a lactogenic activity of an aqueous extract of Cyperus rotundus Linn.

ETHNOPHARMACOLOGICAL RELEVANCE: In Ayurveda, the rhizome of Cyperus rotundus Linn has been reported for wide spectrum of biological activities including lactational therapy for increasing milk quantity. However, not a single report is available on validation of its herbal galactagogue potentiality in literature. Thus, the present study is aimed to assess the lactogenic property of aqueous extract of Cyperus rotundus (CRE). MATERIALS AND METHODS: The effect of aqueous extract of Cyperus rotundus rhizome was evaluated by measuring weight of the pups during suckling period. Quantitatively, total protein and carbohydrate contents of mammary tissue and serum prolactin and cortisol level were calculated. Histopathological analysis of mammary gland, pituitary gland, heart, liver, spleen, kidney, and ovary tissues was carried out. Acute toxicity of CRE against rat was assessed by the Hippocratic test and biochemical profile of blood serum. RESULTS: Oral administration of 300 and 600mg of CRE induced about 23% and 40% more milk in experimental group of animals as compared to the control group of animals. Weight gain by pups and mother rats of treated groups were significantly higher following administration of CRE as compared to that of control group. Moreover protein and carbohydrate content of mammary gland tissue were also significantly more than control group of animals. The CRE was found to stimulate the synthesis of prolactin significantly. In addition, the mammary gland tissues of experimental group showed obvious lobulo-alveolar development with milk secretion. Administration of CRE did not cause any signs or symptoms of toxicity which implied that Cyperus rotundus is toxicologically safe. CONCLUSION: This study demonstrates that the aqueous extract of Cyperus rotundus can stimulate milk production in the female rats which may be consequently effective in increasing the lactation of human too.

Foeniculum vulgare Mill: a review of its botany, phytochemistry, pharmacology, contemporary application, and toxicology.

Foeniculum vulgare Mill commonly called fennel has been used in traditional medicine for a wide range of ailments related to digestive, endocrine, reproductive, and respiratory systems. Additionally, it is also used as a galactagogue agent for lactating mothers. The review aims to gather the fragmented information available in the literature regarding morphology, ethnomedicinal applications, phytochemistry, pharmacology, and toxicology of Foeniculum vulgare. It also compiles available scientific evidence for the ethnobotanical claims and to identify gaps required to be filled by future research. Findings based on their traditional uses and scientific evaluation indicates that Foeniculum vulgare remains to be the most widely used herbal plant. It has been used for more than forty types of disorders. Phytochemical studies have shown the presence of numerous valuable compounds, such as volatile compounds, flavonoids, phenolic compounds, fatty acids, and amino acids. Compiled data indicate their efficacy in several in vitro and in vivo pharmacological properties such as antimicrobial, antiviral, anti-inflammatory, antimutagenic, antinociceptive, antipyretic, antispasmodic, antithrombotic, apoptotic, cardiovascular, chemomodulatory, antitumor, hepatoprotective, hypoglycemic, hypolipidemic, and memory enhancing property. Foeniculum vulgare has emerged as a good source of traditional medicine and it provides a noteworthy basis in pharmaceutical biology for the development/formulation of new drugs and future clinical uses.

Traditional uses, phytochemistry and pharmacology of Ficus carica: a review.

CONTEXT: Ficus carica Linn (Moraceae) has been used in traditional medicine for a wide range of ailments related to digestive, endocrine, reproductive, and respiratory systems. Additionally, it is also used in gastrointestinal tract and urinary tract infection. OBJECTIVE: This review gathers the fragmented information available in the literature regarding morphology, ethnomedicinal applications, phytochemistry, pharmacology, and toxicology of Ficus carica. It also explores the therapeutic potential of Ficus carica in the field of ethnophytopharmacology. MATERIALS AND METHODS: All the available information on Ficus carica was compiled from electronic databases such as Academic Journals, Ethnobotany, Google Scholar, PubMed, Science Direct, Web of Science, and library search. RESULTS: Worldwide ethnomedical uses of Ficus carica have been recorded which have been used traditionally for more than 40 types of disorders. Phytochemical research has led to the isolation of primary as well as secondary metabolites, plant pigment, and enzymes (protease, oxidase, and amylase). Fresh plant materials, crude extracts, and isolated components of Ficus carica have shown a wide spectrum of biological (pharmacological) activities. CONCLUSION: Ficus carica has emerged as a good source of traditional medicine for the treatment of various ailments such as anemia, cancer, diabetes, leprosy, liver diseases, paralysis, skin diseases, and ulcers. It is a promising candidate in pharmaceutical biology for the development/formulation of new drugs and future clinical uses.

Echography of the cervix and uterus during the proliferative and secretory phases of the menstrual cycle in bonnet monkeys (Macaca radiata).

We undertook the present study to investigate the echographic characteristics of the uterus and cervix of female bonnet monkeys ( Macaca radiata ) during the proliferative and secretory phases of the menstrual cycle. The cervix was tortuous in shape and measured 2.74 ± 0.30 cm (mean ± SD) in width by 3.10 ± 0.32 cm in length. The cervical lumen contained 2 or 3 colliculi, which projected from the cervical canal. The echogenicity of cervix varied during proliferative and secretory phases. The uterus was pyriform in shape (2.46 ± 0.28 cm × 1.45 ± 0.19 cm) and consisted of serosa, myometrium, and endometrium. The endometrium generated a triple-line pattern; the outer and central lines were hyperechogenic, whereas the inner line was hypoechogenic. The endometrium was significantly thicker during the secretory phase (0.69 ± 0.12 cm) than during the proliferative phase (0.43 ± 0.15 cm). Knowledge of the echogenic changes in the female reproductive organs of bonnet monkeys during a regular menstrual cycle may facilitate understanding of other physiologic and pathophysiologic changes.

HIV gp120 induced gene expression signatures in vaginal epithelial cells.

Gp120 is the envelope protein of HIV which binds to CD4 independent proteins on vaginal epithelial cells. HIV-gp120 has been reported to modulate gene expression in several cell types. How this interaction may alter the physiologic vaginal milieu during the earliest stages of vaginal transmission of HIV, is currently unknown. Vaginal epithelial cells were treated with HIV-gp120, and a global snapshot of changes in gene expression profiles, were unraveled by microarray analysis. The differentially expressed genes were involved in diverse cellular functions. Genes of immunomodulatory processes and induction of proteases were highly enriched. We propose that the induction of inflammation and proteases may act in concert to weaken the vaginal epithelium, making it more permeable to viral entry. Identification of the gene signatures involved in vaginal-HIV dialogue would aid in understanding the environ induced by HIV itself, as the virus invades and gains entry into its host.

Association of human mannose receptor in sexual transmission of human immunodeficiency virus in serodiscordant couples.

HIV binds specifically to the human mannose receptor (hMR) on vaginal epithelial cells that are devoid of a conventional CD4 receptor. HIV binding to hMR on vaginal epithelial cells induces the production of matrix metalloproteinase 9 (MMP9) leading to degradation of the extracellular matrix, which may increase the risk of HIV entry into vaginal epithelial cells and further transmission into distal cells. Immunofluorescent localization of hMR on vaginal epithelial cells of seronegative females from the general population included the control group (n=52) and seronegative females from serodiscordant couples. There was PCR amplification of DNA from peripheral blood mononuclear cells (PBMCs) of the serodiscordant females for the CCR5 gene flanking the CCR5-Δ32 region; PCR amplification and sequencing of the C2-V3 region of HIV variants in PBMCs and sperm of the infected male partners of the serodiscordant couples; and the presence of hMR on 0-11% of the vaginal epithelial cells of seronegative females (n=39) from serodiscordant couples and 90-95% that of a control group of females (n=52). Nine of these serodiscordant females did not show a CCR5-Δ32 deletion. The translated amino acid sequence of the C2-V3 region of the env gene of HIV-1C in PBMCs (n=9) and sperm (n=5) of the male partners showed the presence of distinct variants and the variation in PBMCs and sperm of serodiscordant males was almost similar to that of infected males from concordant couples. The presence of hMR in a smaller number of vaginal epithelial cells of serodiscordant females prevented binding and HIV entry into these cells and therefore prevented sexual transmission of HIV.

HIV gp120 binds to mannose receptor on vaginal epithelial cells and induces production of matrix metalloproteinases.

BACKGROUND: During sexual transmission of HIV in women, the virus breaches the multi-layered CD4 negative stratified squamous epithelial barrier of the vagina, to infect the sub-epithelial CD4 positive immune cells. However the mechanisms by which HIV gains entry into the sub-epithelial zone is hitherto unknown. We have previously reported human mannose receptor (hMR) as a CD4 independent receptor playing a role in HIV transmission on human spermatozoa. The current study was undertaken to investigate the expression of hMR in vaginal epithelial cells, its HIV gp120 binding potential, affinity constants and the induction of matrix metalloproteinases (MMPs) downstream of HIV gp120 binding to hMR. PRINCIPAL FINDINGS: Human vaginal epithelial cells and the immortalized vaginal epithelial cell line Vk2/E6E7 were used in this study. hMR mRNA and protein were expressed in vaginal epithelial cells and cell line, with a molecular weight of 155 kDa. HIV gp120 bound to vaginal proteins with high affinity, (Kd = 1.2±0.2 nM for vaginal cells, 1.4±0.2 nM for cell line) and the hMR antagonist mannan dose dependently inhibited this binding. Both HIV gp120 binding and hMR exhibited identical patterns of localization in the epithelial cells by immunofluorescence. HIV gp120 bound to immunopurified hMR and affinity constants were 2.9±0.4 nM and 3.2±0.6 nM for vaginal cells and Vk2/E6E7 cell line respectively. HIV gp120 induced an increase in MMP-9 mRNA expression and activity by zymography, which could be inhibited by an anti-hMR antibody. CONCLUSION: hMR expressed by vaginal epithelial cells has high affinity for HIV gp120 and this binding induces production of MMPs. We propose that the induction of MMPs in response to HIV gp120 may lead to degradation of tight junction proteins and the extracellular matrix proteins in the vaginal epithelium and basement membrane, leading to weakening of the epithelial barrier; thereby facilitating transport of HIV across the vaginal epithelium.

Possible transmission of HIV Infection due to human bite.

The potential risk of HIV-1 infection following human bite although epidemiologically insignificant, but it is biologically possible. There are anecdotal reports of HIV transmission by human bites particularly if saliva is mixed with blood. The oral tissues support HIV replication and may serve as a previously unrecognized HIV reservoir. The HIV infected individuals have more viruses in blood than saliva, possibly due to the potent HIV-inhibitory properties of saliva. The case presented here is of a primary HIV infections following a human bite where in the saliva was not blood stained but it got smeared on a raw nail bed of a recipient. The blood and saliva of the source and blood of the recipient showed a detectable viral load with 91% sequence homology of C2-V3 region of HIV gp120 between the two individuals. The recipient did not receive PEP [post exposure prophylaxis] as his family physician was unaware of salivary transmission. The family physician should have taken PEP decision after proper evaluation of the severe and bleeding bite. Hence it is necessary to treat the HIV infected human bites with post exposure prophylaxis.

Characterization of human immunodeficiency virus (HIV1C) variants in peripheral blood mononuclear cells and spermatozoa.

The presence of distinct viral variants in different cells and secretions of the same person influences the transmission of HIV as well as the response to the host defense and to therapy. Sperm-associated virus is also a risk factor for sexual transmission of HIV. Characterization of the C2-V3 region of HIV1C env gene by the Heteroduplex Mobility Assay (HMA) and sequencing demonstrated the presence of distinct variants in the peripheral blood mononuclear cells (PBMCs) and the sperm of the same individual (n = 6). The translated amino acid sequences of HIV variants in the PBMCs of all the study participants (n = 12) and spermatozoa of the six participants characterized showed the presence of distinct variants with different numbers of N-linked glycosylation (NLG) sites. Infectivity of PBMCs of these persons by co-culture with PBMCs from healthy individuals as detected by the p24 levels in the culture supernatant did not show a correlation with the blood plasma viral load. Interestingly, the infectivity of the sperm samples from four of the five individuals showed positive correlation with the viral load in seminal plasma. The study suggests the presence of distinct viral variants in the sperm and PBMCs of the same person with differential infectivity, and the NLG sites may be associated with the affinity of HIV to receptor/co-receptor usages as well as affinity toward neutralizing antibodies which may influence the risk of sperm associated virus in sexual transmission of HIV and transmit the virus further to distal cells.

CD4 independent binding of HIV gp120 to mannose receptor on human spermatozoa.

OBJECTIVE: To characterize the CD4-independent HIV-binding protein of 160 kDa on human spermatozoa. METHODS: The N-terminal amino acid sequence of the 160 kDa protein and its peptide obtained by tryptic digestion were determined. Polymerase chain reaction amplification of human testicular cDNA was performed using degenerate primers corresponding to peptide sequences of the 160 kDa protein. Localization of 160 kDa protein on sperm was performed using fluorescently labeled gp120, followed by inhibition experiments using antagonists to determine the specificity. RESULTS: The partial cDNA sequence of the 160 kDa protein demonstrated 99% identity with human macrophage mannose receptor. Sequence of testicular mannose receptor was obtained and exhibited 99% identity with that of macrophage mannose receptor. Furthermore, mannose receptor protein from sperm extract was found to have a molecular weight of 160 kDa, congruent with that of 160 kDa HIV-binding protein. gp120 binding and mannose receptor expression were localized to the equatorial segment in 10% of ejaculated sperm, which increased after capacitation. Mannan at molar excess concentrations completely inhibited gp120 binding to sperm. CONCLUSIONS: The 160 kDa, CD4-independent HIV-binding sperm protein has been identified as the human mannose receptor protein. The role of mannose receptor in HIV transmission and association with risk of sexual transmission merit further investigation.

Postnatal expression and androgen regulation of HOXBES2 homeoprotein in rat epididymis.

The multifunctional and androgen-regulated epididymis is known to provide a conducive microenvironment for the maturation and storage of mature spermatozoa. HOXB2 homeodomain-containing epididymis-specific sperm protein (HOXBES2), a molecule first reported by our group, exhibits cell- and region-specific expression. It was found in the cytoplasm of the principal epithelial cells with maximum in the distal segments of the rat epididymis. The present study was undertaken to determine whether HOXBES2 expression is regulated by androgens and postnatal epididymal development. Toward this, the epididymis was disallowed access to circulating androgens either by chemical or biologic castration. In bilaterally orchidectomized animals, the levels of immunoreactive HOXBES2 declined to <5 % of those seen in sham-operated animals. Exogenous dihydrotestosterone (DHT) supplementation (250 microg/kg body weight) for 7 days restored the expression levels to >or= 90 % of that observed in intact animals. Ethylene dimethane sulfonate (EDS) administration completely abolished HOXBES2 expression in the epididymis, and supplementation with DHT or DHT + estradiol for 10 days re-established HOXBES2 expression to near normalcy. However, in the estradiol alone-supplemented EDS-treated group, HOXBES2 remained undetected. The unaltered HOXBES2 expression following efferent duct ligation suggested that HOXBES2 is not critically dependent on testicular factors. During postnatal development, protein expression in the epididymis begins to appear from day 40 and 50 and increased from day 60 onward, coinciding with the mature levels of circulating androgens and the well-differentiated epididymis. Thus, the data obtained from this study suggests that HOXBES2 expression could be regulated by androgens, and its expression level is closely associated with the postnatal development of the epididymis.

Studies on the expression of 80-kDa human sperm antigen in rat testis and epididymis.

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 ethylene dimethane sulfonate (EDS), which selectively destroys Leydig cells and thus induces complete androgen withdrawal. It was observed that the staining intensity decreased following EDS treatment in rat testis as well as epididymis, and it was regained after supplementation with dihydrotestosterone. Increased expression during sexual maturation at the time of testosterone surge and its regulation by antiandrogen/androgen treatment suggest androgen-dependent expression of 80-kDa HSA in rat testis and epididymis.

Antifertility effect of passive administration of antibodies to 80 kDa human sperm antigen and its synthetic peptides in male and female rats.

PROBLEM: A human sperm antigen of molecular size of about 80 kDa (80 kDa HSA) has been reported to be sperm-specific, conserved and responsible for inducing immunological infertility. The partial N-terminal amino acid sequence of 80 kDa 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 microL of antibodies or 10 and 40 microg purified immunoglobulins to 80 kDa HSA, peptides NT, 1, 2 and 4 on fertility in male and female rats were investigated. RESULTS: Passive administration of antibodies to 80 kDa 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 microg 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 80 kDa HSA immunobiologically mimicked the native protein and impaired fertility following passive administration of antipeptide antibodies and hence, suggested the suitability of synthetic peptides of 80 kDa HSA as candidates for development of antifertility vaccine.

Extraction, purification, and development of an enzyme-linked immunosorbent assay for osteocalcin.

The present study describes the isolation and purification of osteocalcin (OC) from bovine bones and the development of an enzyme-linked immunosorbent assay (ELISA) for OC as a marker of bone formation, for assessing bone health. Bone proteins were extracted from about 90 g of bovine bone powder using 20% formic acid. The protein extract was fractionated by gel permeation chromatography on Sephadex G-50 column followed by fast protein liquid chromatography (FPLC) on a MONO-Q column. The immunoreactive active fraction was then purified by chromatofocusing, using FPLC on a MONO P column and a single homogeneous band of molecular size of about 5.8kDa, as judged by Tricine SDS-PAGE following silver staining of the gel, was obtained. It reacted specifically with its antibodies in an ELISA. About 678 microg of purified OC was yielded from about 90 g of bovine bones. The purified OC was subsequently used for the raising antisera, which was used in the development of an indirect ELISA. The developed ELISA has a sensitivity of 2.5-4.0 ng/mL and was used in estimating levels of OC in women of various age groups.

Identification of CD4-independent HIV receptors on spermatozoa.

PROBLEM: Human immunodeficiency virus (HIV) has been demonstrated to bind and enter into the spermatozoa facilitating the transmission into urogenital cells. However, spermatozoa has been reported to be devoid of the conventional CD4 receptors for HIV. This suggests that there exists an alternate modality of HIV entry into spermatozoa using receptors other than CD4. Present communication describes the identification of HIV receptors on the spermatozoa. METHOD OF STUDY: The sperm proteins were solubilized using Triton X-100 and subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by Western blot analysis, using cell-free HIV or gp120 envelope glycoprotein as a probe. HIV or gp120 bound protein band was then visualized by using alkaline phosphatase (AP) labeled anti-gp120 antibody as well as by using anti-gp120 antibody and subsequently by AP-labeled anti-rabbit gamma globulin. RESULTS: The results obtained demonstrate for the first time that cell-free HIV and gp120 protein bind specifically to 160 kDa sperm protein that could be the receptor for HIV entry into spermatozoa. CONCLUSION: A 160 kDa sperm protein could be the CD4-independent HIV receptor for HIV to bind and enter into the spermatozoa. Further characterization of this 160 kDa HIV receptor on sperm will provide an insight in understanding the mechanism and probable mode of intervention or prevention of HIV transmission at the initial stage of infection.