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S B Moodbidri

Publications and source records attributed to S B Moodbidri.

At least 19 recordsLinked to original sources

Overexpression of monkey oviductal protein: purification and characterization of recombinant protein and its antibodies.

The secretory cells lining the lumen of the mammalian oviduct synthesize and secrete high molecular weight glycoprotein (OGP). Molecular cDNA cloning of most of the mammalian OGP has been accomplished. The nucleotide and deduced amino acid sequences show a remarkable homology across species and also to chitinase protein. Even though OGP has been shown to interact with gametes and the early embryo, the protein's direct function has not yet been established. A prerequisite for such studies is the availability of well-characterized protein in bulk. We used recombinant DNA technology to obtain OGP (rOGP). An authentic partial cDNA clone encoding bonnet monkey (Macaca radiata) OGP (accession number AF132 215) was recloned into expression vector pET20b. Overexpression of the protein could be demonstrated after induction with isopropylthio-beta-galactopyranoside. Recombinant protein was purified by gel filtration of Escherichia coli lysate through Sephadex G75. The protein migrated with a molecular weight of approximately 14 kDa on SDS-PAGE. The molecular weight as assessed by matrix-assisted laser adsorption time-of-flight was 14 439 daltons. With Western blot procedures the protein could be immunostained with antibodies to human OGP, baboon OGP, and antipeptide antibodies generated against a well-conserved region of mammalian OGP. The monospecificity of rabbit antibodies generated against rOGP was established by its ability to immunostain human OGP (100-110 kDa) isolated from hydrosalpinx by Western blot analysis, and the antibody immunostained epithelial cells that secrete OGP in human fallopian tubes. OGP binding sites on the head and tail region of monkey sperm could be demonstrated by using antibody against rOGP.

Amino Acid Sequence↗

Characterization of 80 kDa human sperm antigen responsible for immunoinfertility.

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.

Amino Acid Sequence↗

Regulation of follicular maturation by human ovarian follicular fluid peptide.

Follicular development, ovulation and luteal function are controlled by gonadotrophins. However, recent evidence indicates that local factors are also responsible for the regulation of folliculogenesis. In addition to their endocrine action on pituitary gonadotrophins, inhibin, activin and follistatin also have a paracrine role in follicular maturation. An ovarian follicular fluid peptide (OFFP) has been identified from sheep and humans. Purification of OFFP has been achieved by ultrafiltration and gel chromatography with further purification by fast performance liquid chromatography and reversed phase-high pressure liquid chromatography. OFFP is a small (< 5 kDa) peptide that competes with FSH in binding to granulosa cells in vitro and inhibits progesterone secretion from granulosa cells in culture. Immunohistochemical localization revealed the presence of OFFP mainly in granulosa cells of ovarian follicles. Furthermore, the peptide caused apoptosis in granulosa cells and induced follicular atresia. OFFP may act indirectly on oocytes via its effect on granulosa cells. The peptide from ovarian follicular fluid appears to have an important autocrine or paracrine role in the regulation of folliculogenesis.

Animals↗

Interference with ovulation and luteal function by human ovarian follicular fluid peptide in bonnet monkeys, Macaca radiata.

Partially purified human ovarian follicular fluid peptide (hGF2) was administered during follicular phase in 5 bonnet monkeys. In control as well as hGF2-injected animals, ovulation was synchronized by treatment with FSH, Pergonal and hCG. All the 5 control bonnet monkeys showed plasma estradiol peak followed by increased progesterone levels. In 4 out of 5 hGF2-injected animals, plasma progesterone levels were drastically reduced. Plasma estradiol levels were decreased only in 3 animals in which amenorrhea was observed. These data reveal that hGF2 injection disrupted ovarian function in bonnet monkeys.

Animals↗

An enzyme-linked immunosorbent assay for the detection of human seminal plasma inhibin.

A simple and sensitive enzyme-linked immunosorbent assay (ELISA) is described for the measurement of inhibin in urine and seminal plasma. Standards used cover a range from 50 ng to 0.05 ng/0.1 ml with a detection limit of 0.098 ng/0.1 ml. Coefficients of variation for intra-assay precision and for inter-assay precision were obtained and compared favourably with RIA. Given the ease of application, this technique is an useful alternative to existing radioimmuno-assays for this peptide.

Enzyme-Linked Immunosorbent Assay↗

Seminal inhibin--prospects for immunocontraception.

Passive immunization of adult rats, hamsters and marmosets with rabbit anti-seminal inhibin resulted in complete or partial block of fertility. The antiserum treatment presumably neutralized endogenous inhibin resulting in an unopposed rise in circulating FSH. This probably led to a refractoriness of the testes to FSH resulting in complete spermatogenic arrest. Nevertheless, there was no change in the mating behaviour of the animals. The antibodies also affected the epididymal spermatozoa by causing large scale agglutination.

Animals↗

Antifertility effects in rats actively immunized with 80 kDa human semen glycoprotein.

A 80 kDa human sperm antigen has been identified using the serum of an infertile woman having circulating antisperm antibodies. The antigen was then purified to homogeneity by gel permeation chromatography using HPLC (protein PAK-125 column) system and on FPLC (superose-12 column) system. The antigen was found to be a glycoprotein. The antigen was mainly localized in the postacrosomal region of the human sperm, while it was localized in the head region of the rat sperm as demonstrated by immunofluorescent staining. The presence of this antigen was also demonstrated in the human prostate and endometrium and in the rat testis; epididymis and the prostate by immunocytochemical staining. The purified protein upon active immunization in female rats caused infertility in 100 percent animals. While in male rats it caused infertility in 90 percent animals. On morphometric analysis of testicular tissue it was observed that there was no significant change in spermatogonia and spermatocytes, but significant decrease in spermatids and sperm number as well as daily sperm production in the immunized male rats. The epididymal spermatozoa were markedly reduced in number and were largely found to be agglutinated. The results suggest that 80 kDa human sperm antigen appears to be a suitable candidate for immunocontraception both in male and female.

Animals↗

Localization and detection of ovarian follicular fluid protein in follicles of human ovaries.

Human ovarian follicular fluid protein has been partially purified and the active fraction designated as hGF2. Using specific polyclonal antiserum to hGF2, it was observed to be localized immunohistochemically in the granulosa cells of medium but not large follicles of human ovary. The hGF2 levels were estimated by ELISA in serum and follicular fluid of 10 gonadotropin-stimulated women recruited for IVF-ET programme. The results revealed a 3-fold increase in the concentration of hGF2 in follicular fluid compared to that in serum of these patients. These data indicate that the protein is secreted by granulosa cells and plays an important role in the regulation of follicular maturation and ovulation.

Chorionic Gonadotropin↗

Suppression of antral formation in the ovarian follicles of marmosets by human ovarian follicular fluid protein.

Ovarian follicular fluid peptide (OFFP) has earlier been shown to inhibit maturation of large follicles and ovulation in mice. An active fraction hGF2, obtained following partial purification from human ovarian follicular fluid, was injected at a dose of 20 micrograms to 4-month-old immature marmosets, every alternate day for 2 months. The animal were autopsied at 4 and 6 months of age. Ovarian morphology indicated the appearance of large follicles at 6 months of age in the control group. In contrast, in hGF2 treated marmosets development up to preantral follicles could be seen at 6 months. Furthermore, only in 1 out of the 3 treated marmosets, presence of large preantral follicles was observed and in the remaining 4 animals only primary and secondary follicles were noted. These results reveal that OFFP suppresses follicular development and antrum formation in marmosets.

Animals↗

Shortening of luteal phase in common marmosets by sheep ovarian follicular fluid peptide.

A low molecular weight peptide has been partially purified from sheep follicular fluid. It inhibited FSH binding to granulosa cells from ovarian follicles of common marmosets (Callithrix jacchus). When injected into cycling marmosets during the follicular phase, it reduced the area under the curve (AUC) of circulating progesterone. The peptide also shortened the luteal phase in all marmosets during the treatment cycle compared to the pretreatment control cycle. These results indicate that the ovarian follicular fluid peptide inhibited FSH binding to granulosa cells thereby probably resulting in decreased progesterone secretion (AUC) from these cells and subsequently inducing luteal insufficiency.

Animals↗

Luteal deficiency caused by human ovarian follicular fluid peptide in post-partum marmosets, Callithrix jacchus.

A peptide purified from human ovarian follicular fluid (hOFFP) was administered during the follicular phase of post-partum marmosets. Four of the five animals treated with hOFFP, ovulated as evidenced by the presence of ovarian stigmata at the time of laparotomy. However, only 2 of these animals became pregnant, one had a normal delivery while the other aborted. A shortening of the luteal phase was observed in the other three animals and all animals conceived in subsequent cycles. The results indicated that treatment with the ovarian follicular fluid peptide resulted in impairment of fertility as a result of luteal insufficiency.

Animals↗

Localization of inhibin in testes of human, bonnet monkey, dog and rat by immunoperoxidase technique.

Immunocytochemical study on the localization of inhibin in the testes of human, bonnet monkey, dog and rat was carried out using indirect immunoperoxidase technique, in order to investigate the cell types involved in inhibin production/storage. A positive reaction was observed in the testes of human, monkey and dog while it was negative in rat testis using specific antiserum to human testicular inhibin generated against homogeneous preparation of human testicular inhibin in our laboratory. Inhibin was found to be localized in Sertoli cells, spermatogonia and primary spermatocytes of human, monkey and dog testes. A weak positive reaction was observed in spermatids of human testis only. Interestingly, Leydig cells of human, monkey and dog testes showed positive reaction indicating presence of inhibin in these cells also.

Animals↗

Does inhibin have intrinsic prolactin suppressing activity?

Evidence to demonstrate suppressive effect of inhibin on prolactin has been presented. The inhibin preparations derived from human testicular tissue, human seminal plasma and porcine follicular fluid were tested and all the three preparations were found to exhibit prolactin suppressing activity.

Animals↗

Localization of inhibin in human testes by immunoperoxidase technique.

Immunohistological studies on the localization of inhibin in human testes were carried out to investigate the cell types involved in inhibin synthesis/storage. The paraffin embedded testicular tissues were stained by an indirect immunoperoxidase technique. Specific antiserum to human testicular inhibin generated against the homogenous preparation of human testicular inhibin at our laboratory was used as the first antibody. Inhibin was found to be localized in Sertoli cells, spermatogonia, and primary spermatocytes. A weak positive reaction was also observed in spermatids. Interestingly, Leydig cells showed positive reaction indicating presence of inhibin in these cells too.

Humans↗

Inhibition of delta 5-3 beta hydroxysteroid dehydrogenase activity in pre-implantation mouse embryos and their implantation by sheep ovarian follicular fluid peptide.

The activity of delta 5-3 beta hydroxysteroid dehydrogenase (delta 5-3 beta HSD) in pre-implantation mouse embryos was inhibited following their prior incubation with partially purified sheep ovarian follicular fluid peptide (OFFP). OFFP, 5 microliter, injected into the uterine lumen of day 4 pregnant mice impaired the ensuing implantation of embryos. Our observations suggest that OFFP may inhibit steroid metabolizing activity in pre-implantation embryos and thereby interfere with the process of implantation.

3-Hydroxysteroid Dehydrogenases↗

Effect of inhibin on testosterone metabolism by rat ventral prostate in vitro.

Conversion of radiolabeled testosterone to 5 alpha-dihydrotestosterone (5 alpha-DHT) was determined in the rat ventral prostate in vitro, and the effect of inhibin on this conversion was demonstrated. The data revealed that the reduction of testosterone to 5 alpha-DHT was inhibited in a dose-related manner in the presence of inhibin as compared with the basal reduction. The percentage of testosterone reduced per 10-mg tissue also showed a similar trend. The ratio of radioactive counts for DHT and testosterone was also minimum at the highest dose of inhibin used. Inhibin can thus modulate the conversion of testosterone to 5 alpha-DHT in the rat ventral prostate, and therefore can autocrine-paracrine function can be attributed to the prostate.

5-alpha Reductase Inhibitors↗