Development and characterization of human fetal female reproductive tract organoids to understand Müllerian duct anomalies.

Müllerian ducts are paired tubular structures that give rise to most of the female reproductive organs. Any abnormalities in the development and differentiation of these ducts lead to anatomical defects in the female reproductive tract organs categorized as Müllerian duct anomalies. Due to the limited access to fetal tissues, little is understood of human reproductive tract development and the associated anomalies. Although organoids represent a powerful model to decipher human development and disease, such organoids from fetal reproductive organs are not available. Here, we developed organoids from human fetal fallopian tubes and uteri and compared them with their adult counterparts. Our results demonstrate that human fetal reproductive tract epithelia do not express some of the typical markers of adult reproductive tract epithelia. Furthermore, fetal organoids are grossly, histologically, and proteomically different from adult organoids. While external supplementation of WNT ligands or activators in culture medium is an absolute requirement for the adult reproductive tract organoids, fetal organoids are able to grow in WNT-deficient conditions. We also developed decellularized tissue scaffolds from adult human fallopian tubes and uteri. Transplantation of fetal organoids onto these scaffolds led to the regeneration of the adult fallopian tube and uterine epithelia. Importantly, suppression of Wnt signaling, which is altered in patients with Müllerian duct anomalies, inhibits the regenerative ability of human fetal organoids and causes severe anatomical defects in the mouse reproductive tract. Thus, our fetal organoids represent an important platform to study the underlying basis of human female reproductive tract development and diseases.

An evo-devo perspective of the female reproductive tract.

The vertebrate female reproductive tract has undergone considerable diversification over evolution, having become physiologically adapted to different reproductive strategies. This review considers the female reproductive tract from the perspective of evolutionary developmental biology (evo-devo). Very little is known about how the evolution of this organ system has been driven at the molecular level. In most vertebrates, the female reproductive tract develops from paired embryonic tubes, the Müllerian ducts. We propose that formation of the Müllerian duct is a conserved process that has involved co-option of genes and molecular pathways involved in tubulogenesis in the adjacent mesonephric kidney and Wolffian duct. Downstream of this conservation, genetic regulatory divergence has occurred, generating diversity in duct structure. Plasticity of the Hox gene code and wnt signaling, in particular, may underlie morphological variation of the uterus in mammals, and evolution of the vagina. This developmental plasticity in Hox and Wnt activity may also apply to other vertebrates, generating the morphological diversity of female reproductive tracts evident today.

Natural Herbal Estrogen-Mimetics (Phytoestrogens) Promote the Differentiation of Fallopian Tube Epithelium into Multi-Ciliated Cells via Estrogen Receptor Beta.

Phytoestrogens are herbal polyphenolic compounds that exert various estrogen-like effects in animals and can be taken in easily from a foodstuff in daily life. The fallopian tube lumen, where transportation of the oocyte occurs, is lined with secretory cells and multi-ciliated epithelial cells. Recently, we showed that estrogen induces multi-ciliogenesis in the porcine fallopian tube epithelial cells (FTECs) through the activation of the estrogen receptor beta (ERß) pathway and simultaneous inhibition of the Notch pathway. Thus, ingested phytoestrogens may induce FTEC ciliogenesis and thereby affect the fecundity. To address this issue, we added isoflavones (genistein, daidzein, or glycitin) and coumestan (coumestrol) to primary culture FTECs under air-liquid interface conditions and assessed the effects of each compound. All phytoestrogens except glycitin induced multi-ciliated cell differentiation, which followed Notch signal downregulation. On the contrary, the differentiation of secretory cells decreased slightly. Furthermore, genistein and daidzein had a slight effect on the proportion of proliferating cells exhibited by Ki67 expression. Ciliated-cell differentiation is inhibited by the ERß antagonist, PHTPP. Thus, this study suggests that phytoestrogens can improve the fallopian tube epithelial sheet homeostasis by facilitating the genesis of multi-ciliated cells and this effect depends on the ERß-mediated pathway.

Mechanical and signaling mechanisms that guide pre-implantation embryo movement.

How a mammalian embryo determines and arrives at its attachment site has been studied for decades, but our understanding of this process is far from complete. Using confocal imaging and image analysis, we evaluate embryo location along the longitudinal oviductal-cervical axis of murine uteri. Our analysis reveals three distinct pre-implantation phases: embryo entry, unidirectional movement of embryo clusters and bidirectional scattering and spacing of embryos. We show that unidirectional clustered movement is facilitated by a mechanical stimulus of the embryo and is regulated by adrenergic uterine smooth muscle contractions. Embryo scattering, on the other hand, depends on embryo-uterine communication reliant on the LPAR3 signaling pathway and is independent of adrenergic muscle contractions. Finally, we demonstrate that uterine implantation sites in mice are neither random nor predetermined but are guided by the number of embryos entering the uterine lumen. These studies have implications for understanding how embryo-uterine communication is key to determining an optimal implantation site necessary for the success of a pregnancy.

Fallopian Tube Basal Stem Cells Reproducing the Epithelial Sheets In Vitro-Stem Cell of Fallopian Epithelium.

The fallopian tube (FT) is an important reproductive organ in females. The luminal epithelium of the FT is composed of highly polarized secretory and ciliated cells. Recently, accumulating lines of evidence have suggested that the origin of high-grade serous ovarian carcinoma (HGSC) is fallopian tube epithelial cells (FTECs). Due to the lack of a high-fidelity model for FTECs in vitro, homeostasis, differentiation, as well as the transformation of FTECs are still enigmatic. In this study, we optimized the culture condition for the stable expansion of basal stem cells, as well as inducing differentiation of basal cells into polarized secretory and ciliated cells in the air-liquid interface (ALI) condition suitable for long-term culture. This storable culture method of FTECs provides a versatile platform for studying differentiation mechanisms, intercellular communication, and transformation to HGSC, as well as the physiological function of the FT in vitro.

Improving effects of Epimedium flavonoids on the selected reproductive features in layer hens after forced molting.

In the present study, for the purpose of investigating the effects of the total flavonoids of Epimedium (TFE) in regard to preventing the development of atrophied oviducts and follicles induced by forced molting, 300-day-old Hy-Line Brown layer hens were divided into 3 study groups as follows: the control (CON) group was the normal group, without forced molting and TFE treatments; the TFE1 group was treated by adding a 1‰ TFE treatment after forced molting; and the TFE0 group was not treated by TFE after forced molting. During this study's experimental process, the egg production rates were recorded each day. In addition, the hens were randomly chosen to be weighed every 4 D and also randomly selected to be sacrificed every 7 D. Then, sample tissues of albumen-secreting part and uterus from the fallopian tube of the layer hens were collected for PCR and hematoxylin-eosin staining tests. The results showed that the body weights, number of follicles, and weights and sizes of the fallopian tube for the TFE1 and TFE0 groups were significantly reduced when compared with those of the control group on the 15th D of the experiment. Furthermore, at the end of study, it was found that the egg production rates, weights of the fallopian tube, and ovarian follicles of TFE1 had recovered to normal levels. At the same time, the serum estrogen and the expressions of the progesterone receptor and estrogen receptor mRNA in fallopian tube were higher than those observed for the TFE0 group. The results of this study provided valuable evidence that TFE could improve the development of atrophied oviducts and increase the egg laying rates, thereby making it a potential multicomponent natural drug for egg production in the future.

Overexpression of ICAM-1 Predicts Poor Survival in High-Grade Serous Ovarian Carcinoma: A Study Based on TCGA and GEO Databases and Tissue Microarray.

Intercellular cell adhesion molecule-1 (ICAM-1), an important adhesion molecule in the immunoglobulin superfamily, is expressed on many cell types. Recent studies have identified ICAM-1 as a potential oncogene that promotes the development of epithelial ovarian cancer (EOC); it was also found to be associated with poor survival. However, the clinical significance of its expression in high-grade serous ovarian carcinoma (HGSOC) is unclear. Thus, this study aimed to investigate the significance of ICAM-1 expression in HGSOC. Data on ICAM1 expression and mutations in serous ovarian carcinoma (SOC) were obtained from the Cancer Genome Atlas (TCGA), and ICAM1 mRNA expression data in HGSOC were obtained from the Gene Expression Omnibus (GEO) database. ICAM-1 expression was evaluated by immunohistochemistry in HGSOC and normal fallopian tube tissues microarray. In TCGA data, amplification/mutation of ICAM1 was identified in 12% of serous ovarian carcinoma samples, and overexpression of ICAM1 mRNA predicted reduced overall survival in SOC. From TCGA and GEO data, SOC patients with ICAM1 mRNA overexpression treated with chemotherapeutic drugs that contained taxol or taxol and platin together had significantly reduced progression-free survival. According to GEO data, ICAM1 mRNA expression was found significantly higher in HGSOC than in control samples. In our study, ICAM-1 overexpression was observed in 63.1% (65/103) of HGSOCs. As a prognostic biomarker, overexpression of ICAM-1 predicted reduced recurrence-free and overall survival and is an independent risk factor for poor prognosis. These findings suggest that overexpression of ICAM-I is an independent indicator of poor prognosis for HGSOC and that it can serve as an effective clinical prognostic biomarker for this disease.

Profiling of proteins secreted in the bovine oviduct reveals diverse functions of this luminal microenvironment.

The oviductal microenvironment is a site for key events that involve gamete maturation, fertilization and early embryo development. Secretions into the oviductal lumen by either the lining epithelium or by transudation of plasma constituents are known to contain elements conducive for reproductive success. Although previous studies have identified some of these factors involved in reproduction, knowledge of secreted proteins in the oviductal fluid remains rudimentary with limited definition of function even in extensively studied species like cattle. In this study, we used a shotgun proteomics approach followed by bioinformatics sequence prediction to identify secreted proteins present in the bovine oviductal fluid (ex vivo) and secretions from the bovine oviductal epithelial cells (in vitro). From a total of 2087 proteins identified, 266 proteins could be classified as secreted, 109 (41%) of which were common for both in vivo and in vitro conditions. Pathway analysis indicated different classes of proteins that included growth factors, metabolic regulators, immune modulators, enzymes, and extracellular matrix components. Functional analysis revealed mechanisms in the oviductal lumen linked to immune homeostasis, gamete maturation, fertilization and early embryo development. These results point to several novel components that work together with known elements mediating functional homeostasis, and highlight the diversity of machinery associated with oviductal physiology and early events in cattle fertility.

Effects of birthweight on reproductive system development and onset of puberty in gilts.

The aim of the present study was to investigate the effects of birthweight on bodyweight development, development of the genital tract, onset of puberty and their associations with insulin-like growth factor (IGF) 1 and leptin concentrations. Pairs of littermate gilts from 51 litters were selected: one piglet with the highest birthweight (HW; 1.5±0.2kg) and the other with the lowest birthweight (LW; 1.0±0.2kg). Gilt pairs were killed at either fixed ages (80.8±1.2 days; AG; 16 pairs), fixed bodyweight (35.2±1.4kg; WG; 16 pairs) or after first oestrus (EG; 19 pairs). In the AG group, HW gilts were 5.6kg heavier at the time of death than LW gilts. In the WG group, LW gilts were 5.9 days older at the time of death (P<0.05). There were no significant differences in the number or size of total antral follicles or in the follicle population among birthweight classes. Age at puberty was similar between the HW and LW gilts, but bodyweight at time of death was greater for HW gilts (P<0.05). Birthweight did not affect the development of the genital tract, ovulation rate or hormone plasma concentrations. These results suggest that birthweight does not affect the development of the genital tract before puberty and puberty onset.

Global analysis of differential gene expression related to long-term sperm storage in oviduct of Chinese Soft-Shelled Turtle Pelodiscus sinensis.

Important evolutionary and ecological consequences arise from the ability of female turtles to store viable spermatozoa for an extended period. Although previous morphological studies have observed the localization of spermatozoa in Pelodiscus sinensis oviduct, no systematic study on the identification of genes that are involved in long-term sperm storage has been performed. In this study, the oviduct of P. sinensis at different phases (reproductive and hibernation seasons) was prepared for RNA-Seq and gene expression profiling. In total, 2,662 differentially expressed genes (DEGs) including 1,224 up- and 1,438 down-regulated genes were identified from two cDNA libraries. Functional enrichment analysis indicated that many genes were predominantly involved in the immune response, apoptosis pathway and regulation of autophagy. RT-qPCR, ELISA, western blot and IHC analyses showed that the expression profiles of mRNA and protein in selected DEGs were in consistent with results from RNA-Seq analysis. Remarkably, TUNEL analysis revealed the reduced number of apoptotic cells during sperm storage. IHC and TEM analyses found that autophagy occurred in the oviduct epithelial cells, where the spermatozoa were closely attached. The outcomes of this study provide fundamental insights into the complex sperm storage regulatory process and facilitate elucidating the mechanism of sperm storage in P. sinensis.

Mechanical Regulation of Three-Dimensional Epithelial Fold Pattern Formation in the Mouse Oviduct.

Epithelia exhibit various three-dimensional morphologies linked to organ function in animals. However, the mechanisms of three-dimensional morphogenesis remain elusive. The luminal epithelium of the mouse oviduct forms well-aligned straight folds along the longitudinal direction of the tubes. Disruption of the Celsr1 gene, a planar cell polarity-related gene, causes ectopically branched folds. Here, we evaluated the mechanical contributions of the epithelium to the fold pattern formation. In the mutant oviduct, the epithelium was more intricate along the longitudinal direction than in the wild-type, suggesting a higher ratio of the longitudinal length of the epithelial layer to that of the surrounding smooth muscle (SM) layer (L-Epi/SM ratio). Our mathematical modeling and computational simulations suggested that the L-Epi/SM ratio could explain the differences in fold branching between the two genotypes. Longitudinal epithelial tensions were increased in well-aligned folds compared with those in disorganized folds both in the simulations and in experimental estimations. Artificially increasing the epithelial tensions suppressed the branching in simulations, suggesting that the epithelial tensions can regulate fold patterning. The epithelial tensions could be explained by the combination of line tensions along the epithelial cell-cell boundaries with the polarized cell arrays observed in vivo. These results suggest that the fold pattern is associated with the polarized cell array through the longitudinal epithelial tension. Further simulations indicated that the L-Epi/SM ratio could contribute to fold pattern diversity, suggesting that the L-Epi/SM ratio is a critical parameter in the fold patterning in tubular organs.

Lgr5 marks stem/progenitor cells in ovary and tubal epithelia.

The ovary surface epithelium (OSE) undergoes ovulatory tear and remodelling throughout life. Resident stem cells drive such tissue homeostasis in many adult epithelia, but their existence in the ovary has not been definitively proven. Lgr5 marks stem cells in multiple epithelia. Here we use reporter mice and single-molecule fluorescent in situ hybridization to document candidate Lgr5(+) stem cells in the mouse ovary and associated structures. Lgr5 is broadly expressed during ovary organogenesis, but becomes limited to the OSE in neonate life. In adults, Lgr5 expression is predominantly restricted to proliferative regions of the OSE and mesovarian-fimbria junctional epithelia. Using in vivo lineage tracing, we identify embryonic and neonate Lgr5(+) populations as stem/progenitor cells contributing to the development of the OSE cell lineage, as well as epithelia of the mesovarian ligament and oviduct/fimbria. Adult Lgr5(+) populations maintain OSE homeostasis and ovulatory regenerative repair in vivo. Thus, Lgr5 marks stem/progenitor cells of the ovary and tubal epithelia.

In vitro maturation (IVM) of murine and human germinal vesicle (GV)-stage oocytes by coculture with immortalized human fallopian tube epithelial cells.

OBJECTIVE: To improve the maturation rate of murine and human germinal vesicle (GV) oocytes using human tubal epithelial cells (hTECs). DESIGN: Murine and human GV oocytes were randomized to human tubal fluid (HTF) media alone or cocultured with mouse embryonic fibroblasts (MEFs) or primary hTECs or immortalized hTECS (ihTECs) for various times. Rates of maturation to meiosis II (MII) were compared between groups. INTERVENTION(S): TECs were isolated from discarded salpingectomy specimens. One batch was immortalized with TERT and SV40 large T-antigen. GV oocytes (n = 710) were isolated from 8-week-old-mice at 40 hours after pregnant mare's serum gonadotropin stimulation. Discarded human GV oocytes (n = 62) were obtained from intracytoplasmic sperm injection cycle IVF center patients. Oocytes were cultured in HTF media alone or with MEFs, hTECs, or ihTECs. MAIN OUTCOME MEASURE(S): Maturation rates were assessed by standard morphological criteria and compared. RESULT(S): The maturation rate of murine GV oocytes to MII at 12 and 24 hours increased significantly in coculture with hTECS and ihTECS compared with MEF and HTF media alone. In addition, the development rate after IVF was significantly higher with hTECS and ihTECS than in MEF and HTF media alone. Maturation of human GV oocytes to MII at 24 and 48 hours was significantly higher in hTECS and ihTECS compared with HTF media alone. CONCLUSION(S): Coculture with either primary or immortalized TECs might improve oocyte quality and significantly raise in vitro maturation rates for GV oocytes.

Conditional deletion of beta-catenin mediated by Amhr2cre in mice causes female infertility.

Follicle-stimulating hormone (FSH) regulation of aromatase gene expression in vitro requires the transcriptional coactivator beta-catenin. To ascertain the physiological significance of beta-catenin in granulosa cells during folliculogenesis, mice homozygous for floxed alleles of beta-catenin were intercrossed with Amhr2cre mice. Conditional deletion of beta-catenin in 8-wk-old females occurred in derivatives of the Müllerian duct, granulosa cells and, surprisingly, in brain, pituitary, heart, liver, and tail. Female mice deficient for beta-catenin were infertile, despite reaching puberty and ovulating at the expected age, indications of apparently normal ovarian function. In contrast, their oviducts were grossly distended, with fewer but healthy oocytes. In addition, their uteri lacked implantation sites. Together, these two phenotypes could explain the complete loss of fertility. Nevertheless, although the ovary appeared normal, with serum estradiol concentrations in the normal range, there was marked animal-to-animal variation of mRNAs encoding beta-catenin and aromatase. Similarly, inhibin-alpha and luteinizing hormone receptor mRNAs varied considerably in whole ovaries, whereas pituitary Fshb mRNA was significantly reduced. Collectively, these features suggested cyclization recombination (CRE)-mediated recombination of beta-catenin may be unstable in proliferating granulosa cells, and therefore may mask the suspected steroidogenic requirement for beta-catenin. We tested this possibility by transducing primary cultures of granulosa cells from mice homozygous for floxed alleles of beta-catenin with a CRE-expressing adenovirus. Reduction of beta-catenin significantly compromised FSH stimulation of aromatase mRNA and subsequent production of estradiol. Collectively, these data suggest that FSH regulation of steroidogenesis requires beta-catenin, a role that remains hidden when tested through Amhr2cre-mediated recombination in vivo.

Essential roles of mesenchyme-derived beta-catenin in mouse Müllerian duct morphogenesis.

Members of the Wnt family of genes such as Wnt4, Wnt5a, and Wnt7a have been implicated in the formation and morphogenesis of the Müllerian duct into various parts of the female reproductive tract. These WNT ligands elicit their action via either the canonical WNT/beta-catenin or the non-canonical WNT/calcium pathway and could possibly function redundantly in Müllerian duct differentiation. By using the Müllerian duct-specific anti-Müllerian hormone receptor 2 cre (Amhr2-cre) mouse line, we established a conditional knockout model that removed beta-catenin specifically in the mesenchyme of the Müllerian duct. At birth, loss of beta-catenin in the Müllerian duct mesenchyme disrupted the normal coiling of the oviduct in the knockout embryo, resembling the phenotype of the Wnt7a knockout. The overall development of the female reproductive tract was stunted at birth with a decrease in proliferation in the mesenchyme and epithelium. We also discovered that Wnt5a and Wnt7a expression remained normal, excluding the possibility that the phenotypes resulted from a loss of these WNT ligands. We examined the expression of Frizzled (Fzd), the receptors for WNT, and found that Fzd1 is one receptor present in the Müllerian duct mesenchyme and could be the putative receptor for beta-catenin activation in the Müllerian duct. In summary, our findings suggest that mesenchymal beta-catenin is a downstream effector of Wnt7a that mediates the patterning of the oviduct and proper differentiation of the uterus.

Emerging roles for PAX8 in ovarian cancer and endosalpingeal development.

OBJECTIVES: Epithelial ovarian carcinomas develop from ovarian surface epithelia that undergo complex differentiation to form distinguishable phenotypes resembling those of the epithelia of the female urogenital regions. While previous studies have implicated regulatory developmental homeobox (HOX) genes in this process, other factors responsible for this differentiation are largely unknown. Aberrant transcriptional expression of PAX8 has been reported in epithelial ovarian cancer, prompting us to initiate the molecular characterization of this master regulatory gene in ovarian cancer development. METHODS: Immunohistochemistry, immunoblotting and RT-PCR were used to investigate the presence of PAX8 and its protein products in epithelial ovarian cancer subtypes, normal ovarian surface epithelia, ovarian inclusion cysts and normal endosalpingeal epithelia. RESULTS: In this report, we confirm microarray results indicating that the transcription factor, PAX8, is highly expressed in epithelial ovarian cancer but absent from the precursor ovarian surface epithelia of healthy individuals. Furthermore, we report that PAX8 is localized to the nucleus of non-ciliated epithelia in simple ovarian epithelial inclusion cysts and in three epithelial ovarian cancer subtypes (serous, endometrioid and clear cell). We also determined that PAX8 is expressed in the non-ciliated, secretory cells of healthy fallopian tube mucosal linings but not in the adjacent ciliated epithelia. CONCLUSION: These findings support the hypothesis that PAX8 plays parallel roles in the development of epithelial ovarian cancer and in the developmental differentiation of coelomic epithelia into endosalpingeal epithelia.

Epithelial c-jun and c-fos are temporally and spatially regulated by estradiol during neonatal rat oviduct differentiation.

Expression of transcription factors binding to the activating protein-1 (AP-1) site is induced by estrogens in association with epithelial proliferation in the uterus, but, in the oviduct, the relationship between cell proliferation and differentiation and AP-1 transcription factors is not well understood. In the developing rat oviduct, we found that proliferation and differentiation of epithelial cells were region-dependently regulated by 17beta-estradiol (E2). To determine the role of AP-1 transcription factors in the development of rat oviduct, we performed immunohistochemistry for epithelial c-jun and c-fos proteins in E2-untreated and -treated newborn rats. E2 increased the expression of c-jun and c-fos during proliferation of undifferentiated epithelial cells, but diminished both proteins during accelerated differentiation of ciliated epithelial cells. A pure estrogen receptor (ER) antagonist, ICI 182,780, inhibited changes in their expression during both cell proliferation and differentiation. Importantly, no reduction of c-jun was noted in the epithelial cells of the foxj1-deficient oviduct, which lacks cilia development. This study shows that c-jun and c-fos are regulated during epithelial cell proliferation and differentiation in a region-specific manner. This provides critical information for understanding the molecular and cellular mechanisms of the development of the neonatal oviduct.

Morphometrical changes of the human uterine tubes according to aging and menstrual cycle.

Studies on the morphological changes in the human uterine tube according to aging and menstrual cycle so far have been limited to microscopic aspects such as cellular changes, mainly due to the inaccessibility of specimens. In this study, postmortem analysis using both macroscopic and microscopic methods was performed using 55 human uterine tubes. The numbers and the degrees of convolution, and the length of the uterine tube had a tendency to decrease according to the increase of age in women by fifties. Under the influence of menopause, the total areas of the tube, mucosal layer and lumen in the ampulla, and lumen in the isthmus and infundibulum were shown to decrease on cross section. However, in the isthmus and infundibulum, the cross sectional area of the tube and mucosal layer did not show statistically significant changes. In the women at reproductive stages, the cross sectional areas of the tube, mucosa and lumen showed variations among different individuals, which may be due to the influence of menstrual cycle rather than the increase of age. No venous engorgement of the tubes was observed at the early proliferative, the mid-secretory and the postmenopausal stage. By contrast, full engorgement was observed at the early secretory stage and the menstrual stage.

PDC-109 (BSP-A1/A2) promotes bull sperm binding to oviductal epithelium in vitro and may be involved in forming the oviductal sperm reservoir.

Sperm reservoirs have been found in the oviducts of several species of mammals. In cattle, the reservoir is formed by the binding of sperm to fucose-containing glycoconjugates on the surface of oviductal epithelial cells. A fucose-binding molecule was purified from sperm extracts and identified as PDC-109 (BSP-A1/A2), a protein that is secreted by the seminal vesicles and associates with the plasma membrane of sperm upon ejaculation. The objective of this study was to demonstrate that PDC-109 promotes bull sperm binding to oviductal epithelium. PDC-109 was purified from bovine seminal plasma, and polyclonal antibodies were produced in rabbits. The antibodies detected PDC-109 on ejaculated sperm by indirect immunofluorescence and Western blots of extracts, but PDC-109 was not detected on epididymal sperm. When added to epididymal sperm, purified PDC-109 was absorbed onto the plasma membrane overlying the acrosome, as demonstrated by indirect immunofluorescence and by labeling sperm directly with fluorescein-conjugated PDC-109. When added to explants of oviductal epithelium, significantly fewer epididymal sperm than ejaculated sperm became bound. Addition of PDC-109 to epididymal sperm increased epithelial binding to the level observed for ejaculated sperm. In addition, binding of ejaculated sperm to oviductal epithelium was inhibited by addition of excess soluble PDC-109. Ejaculated sperm lost the ability to bind to oviductal epithelium after heparin-induced capacitation, but treatment with PDC-109 restored binding. These results demonstrate that PDC-109 enables sperm to bind to oviductal epithelium and plays a major role in formation of the bovine oviductal sperm reservoir.

Developmental effects of perinatal exposure to bisphenol-A and diethylstilbestrol on reproductive organs in female mice.

Reproductive tract development is influenced by estrogen. The aim of this study was to determine the effects of an environmental estrogenic chemical bisphenol-A (BPA) on prenatal and postnatal development of female mouse reproductive organs. In the prenatal treatment group, BPA or the synthetic estrogen diethylstilbestrol (DES) were given by subcutaneous (s.c.) injections to pregnant mice during gestational days 10-18. Some offspring treated prenatally with 10 and 100 mg/kg bw BPA or 0.67 and 67 microg/kg bw DES were ovariectomized at 30 days and sacrificed at 40 days of age. Vaginal smears were examined in the remaining offspring, then these offspring were mated with normal males. Prenatal exposure to 10 mg/kg BPA reduced the number of mice with corpora lutea compared to sesame oil controls at 30 days, but more than 80% of mice from either prenatally exposed BPA group were fertile at 90 days. Mice exposed prenatally to maternal doses of 67 microg/kg DES were sterile and showed ovary-independent vaginal and uterine epithelial stratification; however, mice exposed prenatally to BPA did not show ovary-independent vaginal and uterine changes. The number of offspring and litter sex ratio from mice exposed prenatally to BPA (10 or 100 mg/kg) or 0.67 microg/kg DES were not different compared to controls. In postnatal treatment group, female mice were given s.c. injections of BPA (15 or 150 microg/pup) or DES (0.3 or 3 microg/pup) for 5 days from the day of birth, then some mice were ovariectomized at 30 days and examined at 40 and 90 days. In the remaining mice, vaginal smears were examined from 61 to 90 days and ovarian histology was evaluated at 90 days. Mice exposed postnatally to 150 microg BPA exhibited ovary-independent vaginal epithelial stratification. Postnatal DES (0.3 and 3 microg) treatment also induced ovary-independent vaginal stratification. Polyovular follicles having more than one oocyte in a follicle were induced by postnatal injections of BPA (150 microg) or DES (0.3 or 3 microg) at 30 days. These findings indicate for the first time that a large dose of BPA can induce ovary-independent vaginal epithelial changes when given postnatally but not prenatally.