Identification and immunohistochemical localization of a haptoglobin-like protein in the tissues and fluids of the bovine (Bos taurus) ovary and oviduct

The objective of this study was to establish the identity of a 40 kDa bovine oviductal fluid protein as a haptoglobin-like protein and to evaluate the association of the haptoglobin-like protein with ovarian and oviductal tissues and fluids. An oviductal fluid protein band corresponding to a molecular mass of 40 kDa was excised and electroeluted from SDS-PAGE gels. Sequence analysis revealed an N-terminal region sharing 81% identity with the beta-subunit of bovine haptoglobin. The 40 kDa oviductal fluid protein crossreacted on immunoblots with antiserum against rabbit endometrial haptoglobin and with an anti-human haptoglobin polyclonal antibody. Two-dimensional PAGE revealed four protein variants ranging in pI from 7.7 to 8.6, which appeared identical, with respect to molecular weight, number of isoforms and pI, to bovine haptoglobin in acute phase serum. The haptoglobin-like protein was localized using immunohistochemistry to the lumina of blood vessels and to the extracellular matrix of ovarian and oviductal tissues. Immunostaining for the haptoglobin-like protein was also detected in the oviductal lumen, in the mucosa of the ampullary oviduct but not the isthmic oviduct, and in intermittent ampullary epithelial cells. Within the ovary, the haptoglobin-like protein was localized to the avascular granulosa cells and follicular fluid of antral follicles, but not in the theca cells or in preantral follicles of any developmental stage. It was concluded that the haptoglobin-like protein is a normal constituent of bovine ovarian and oviductal tissues and fluids, and it was hypothesized that the haptoglobin-like protein contributes to ovarian follicular development and oviductal function.

Müllerian tumor (atypical polypoid adenomyoma) with sex-cord differentiation arising from the oviduct in an adolescent cynomolgus monkey (Macaca fascicularis)

In a 6.5-year-old cynomolgus monkey (Macaca fascicularis), a tumor mass was macroscopically located near the right ovary, connected to the oviduct, and completely separated from the uterus. The mass was an elongated spherical shape with a smooth surface and milky-white color. It was approximately 3.5 cm across its major axis, and the sagittal section was composed of cystic walls and a multi-lobular luminal nodule. Light-microscopically, the polypoid mass consisted of admixtures of neoplastic mesenchymal and epithelial elements. Lipid-rich foamy cells scattered within the tumor mass formed nest-like/aggregated populations. Immunohistochemically, mesenchymal tumor cells stained diffusely positive for vimentin, desmin, and alpha (alpha)-smooth muscle actin, demonstrating a smooth muscle origin. Mesenchymal tumor cells contained mitotic figures, and tumor elements including mesenchymal, epithelial, and lipid-rich foamy cells stained strongly positive for proliferating cell nuclear antigen (PCNA). Moreover, lipid-rich foamy cells elicited positive reactions for testosterone, suggesting sex-cord element differentiation. Electron-microscopically, actin filaments, basement membranes, and electron-dense cytoplasmic bodies were noted in the spindle cells, and invaginated nuclei were observed in adenomatous cells. In contrast, foamy cells contained numerous lipid vacuoles in the cytoplasm. From these findings, the tumor was diagnosed as an atypical polypoid adenomyoma (benign mixed müllerian tumor) with sex-cord differentiation arising from the oviduct. This tumor was considered to be an exceedingly rare finding in the adolescent cynomolgus monkey.

Location and intensity of IL-8 and TGF-beta2 mRNA production in the fimbrial compartment of fallopian tubes and IL-10 in the endometrium in patients with pyoinflammatory adnexal diseases

The location and level of IL-8 and TGF-beta2 expression in the fimbrial compartment of fallopian tubes and IL-10 expression in the endometrium of women with pyoinflammatory adnexal diseases were studied by in situ hybridization. These diseases are associated with considerable changes in the levels of local production of these cytokines. Inflammatory infiltration and epithelial cells were most active producers of IL-9 and TGF-beta2 in the fimbrial compartment of fallopian tubes, while in the endometrium IL-10 gene was expressed at a high level primarily in the glandular epithelial cells.

Transmembrane and truncated (SEC) isoforms of MUC1 in the human endometrium and Fallopian tube

The cell surface mucin MUC1 is expressed by endometrial epithelial cells with increased abundance in the secretory phase of the menstrual cycle, when it is found both at the apical cell surface and in secretions. This suggests the presence of a maternal cell surface glycoprotein barrier to embryo implantation, arising from the anti-adhesive property of MUC1. In previous work, we demonstrated alternatively spliced MUC1 variant forms in tumour cells. The variant MUC1/SEC lacks the transmembrane and cytoplasmic sequences found in the full-length variant. We now show that MUC1/SEC mRNA is present in endometrial carcinoma cell lines, endometrial tissue and primary cultured endometrial epithelial cells. The protein can be detected using isoform-specific antibodies in uterine flushings, suggesting release from endometrium in vivo. However, on the basis of immunolocalisation studies, MUC1/SEC also remains associated with the apical epithelial surface both in tissue and in cultured cells. Transmembrane MUC1 and MUC1/SEC are both strikingly localised to the apical surface of tubal epithelium. Thus MUC1 may contribute to the anti-adhesive character of the tubal surface, inhibiting ectopic implantation. The mechanism by which this barrier is overcome in endometrium at implantation is the subject of ongoing investigation.

Immunohistochemical localization and expression of the hyaluronan receptor CD44 in the epithelium of the pig oviduct during oestrus

Hyaluronan is related to essential reproductive processes in pigs. Hyaluronan produced by cumulus cells builds, via specific cell surface receptors, an extracellular matrix responsible for cumulus cell cloud expansion during final oocyte maturation, a preparatory event for ovulation and fertilization. In addition, hyaluronan that has been localized in the pig oviduct both in the intraluminal fluid and on the surface of the lining epithelium of the preovulatory sperm reservoir, has proven beneficial during in vitro fertilization and embryo culture, thus indicating that it has a role in vivo. This study monitored the immunolocalization, protein determination and gene expression of the major cell surface hyaluronan receptor CD44 in the epithelial lining of the pig oviduct during selected stages of standing oestrus, in relation to spontaneous ovulation. The CD44 immunostaining in the lining epithelium was localized to the surface membrane and the supranuclear domain of mainly the secretory cells, particularly in the sperm reservoir of both treatment (inseminated) and control (non-inseminated) specimens. Up to four hyaluronan-binding protein (HABP) bands (60, 90, 100 and 200 kDa) were detected in the tubal epithelium, and the 200 kDa band was determined as CD44 by immunoblotting. The expression of CD44 mRNA was higher before than after ovulation (P < 0.05), most conspicuously in the uterotubal junction (UTJ). In addition, CD44 expression in the preovulatory UTJ and the ampullary-isthmic junction (AIJ) of control animals was higher than in those that were inseminated (P < 0.05 and P < 0.01 for UTJ and AIJ, respectively). The results demonstrate for the first time that the specific hyaluronan receptor CD44 is expressed by the oviduct epithelial cells during spontaneous oestrus, and is particularly abundant in the sperm reservoir before ovulation. Presence of spermatozoa in this segment seemed to downregulate the receptor. The variation in the expression of CD44 in relation to spontaneous ovulation and the presence of spermatozoa indicate that the hyaluronan CD44-signalling pathway may play a role in oviduct function during sperm storage and fertilization in pigs.

N-Acylethanolamines in human reproductive fluids

N-Acylethanolamines (NAEs) are an important family of lipid-signaling molecules. Arachidonylethanolamide (anandamide) (AEA), palmitoylethanolamide (PEA), and oleoylethanolamide (OEA) are co-produced from similar phospholipid precursors when neurons are stimulated. AEA is an endogenous agonist (endocannabinoid) for cannabinoid receptors. It binds with higher affinity to type CB1 than to type CB2 cannabinoid receptors. PEA does not bind to CB1, while the hypothesis that it reacts with putative CB2-like receptors has been questioned. OEA does not activate currently known cannabinoid receptors, but it mimics the effects of AEA and cannabinoids in reducing the fertilizing capacity of sea urchin sperm. OEA and PEA also act as entourage compounds by inhibiting the hydrolysis of AEA by fatty acid amide hydrolase. Cannabinoid receptors and/or AEA are present in mammalian reproductive organs including the testis, epididymis, prostate, ovary, uterus, sperm, preimplantation embryo and placenta, as well as prostatic and mammary carcinomas. We now report that analysis by high-performance liquid chromatography/mass spectrometry (HPLC/MS) shows the presence of AEA, PEA, and OEA in human seminal plasma, mid-cycle oviductal fluid, follicular fluid, amniotic fluid, milk, and fluids from malignant ovarian cysts. Previous studies showed that AEA-signaling via cannabinoid receptors regulates capacitation and fertilizing potential of human sperm, early embryonic development and blastocyst implantation into the uterine mucosa of rodents, as well as proliferation of human mammary and prostatic carcinomas. Current results imply that NAEs also may modulate follicular maturation and ovulation, normal and pathological ovarian function, placental and fetal physiology, lactation, infant physiology, and behavior. Collectively, these findings suggest that NAEs in human reproductive fluids may help regulate multiple physiological and pathological processes in the reproductive system, and imply that exogenous cannabinoids delivered by marijuana smoke might impact these processes. This study has potential medical and public policy ramifications because of the incidence of marijuana abuse by adolescents and adults in our society, previously documented reproductive effects of marijuana, and the ongoing debate about medicinal use of marijuana and cannabinoids.

Evidence for a potential role of estrogen in the penis: detection of estrogen receptor-alpha and -beta messenger ribonucleic acid and protein

Body tissues are traditionally classified as estrogen targets based on both the response to the hormone and the presence of estrogen receptors (ERs). We undertook the study on expression of ERalpha and ERbeta in the penis to identify compartments/cells responsive to estrogen, using immunohistochemistry, Western blotting, in situ hybridization, and RT-PCR analyses. Expressions of ERalpha and ERbeta in the rat penis were age dependent at both mRNA and protein levels, with the most intense signals being observed during the perinatal period and declining thereafter with age. Initial signals (fetal d 17) of ERalpha were localized to the mesenchyme and subepithelial stroma and later (postnatal d 2) to the corpus spongiosus, corpus cavernosus, and urethral epithelia. ERbeta was initially detected by postnatal d 2 and was localized diffusely in corpus spongiosus and cavernosus in immature rats. In the adult, both ERs were concentrated largely to the urethral epithelia and vascular and neuronal structures. The present study provides the first evidence for ER expression in the penis. Thus, our data add the penis to the list of estrogen-responsive tissues in males and provide a base and insight for future studies aimed at investigating a functional role of estrogen in the penis, especially in development.

Effects of BST on oviductal and uterine genes encoding components of the IGF system in lactating dairy cows

Lactating Holstein cows, averaging 80 d in milk, were used to examine effects of exogenous bovine somatotropin (bST) on oviductal and uterine genes encoding components of the insulin-like growth factor (IGF) system. About 12 h before expected ovulation in an Ovsynch protocol, cows were assigned randomly to receive bST (500 mg; n = 11) or serve as untreated controls (n = 10). Cows that ovulated (n = 9 bST, 8 control) were divided within treatment to be sacrificed on d 3 or 7 postovulation. Samples of oviductal and intercaruncular endometrial tissue from oviducts and uterine horns ipsilateral to the corpus luteum (CL) were collected and immediately frozen at -80 degrees C for subsequent mRNA analyses. Northern blots revealed mRNAs for IGF-II, IGF-binding protein-2 (IGFBP-2), and IGFBP-3 in all oviductal and endometrial tissues. Significant amounts of IGF-I and growth hormone receptor-1A (GHR-1A) mRNAs were detected in uteri but not in oviducts. The bST treatment had no effect on amount of IGF-I mRNA transcript in uterine endometrium. The mRNA encoding IGF-II was induced by bST in oviducts collected on both d 3 and 7 but was down-regulated in endometrium on d 7. Transcript of IGFBP-2 mRNA was greater in endometrial than oviductal tissues and did not differ between treatments. Both oviductal and endometrial IGFBP-3 mRNA concentrations increased between d 3 and 7 postovulation, with a tendency for greater endometrial IGFBP-3 mRNA in bST-treated cows on d 7. On d 7, concentrations of endometrial GHR-1A mRNA were 30% lower in bST-treated cows. Results indicate complex and tissue-specific regulation of the uterine IGF system components by exogenous bST. Some of those biological responses to bST may be important in early development of bovine embryos.

Production of activins by the human endosalpinx

Uterine tubes from 11 premenopausal and 6 postmenopausal women were collected and examined for the presence of inhibin, activin, and follistatin in the endosalpinx. Immunocytochemistry of tissue from both the isthmic and ampullary regions demonstrated clear staining for the beta(A)- and beta(B)-subunits that increased in intensity from the isthmus to the ampulla. Staining for follistatin showed a similar pattern, but no staining for the alpha-subunit was observed. Although staining for the beta(A)-subunit was seen in almost every epithelial cell, staining for the beta(B)-subunit was more variable. Western blotting showed a band with an apparent molecular mass of 28 kDa (corresponding to the activin dimer) and a band of approximately 60 kDa (corresponding to the pro-protein of activin). In situ hybridization confirmed the presence of mRNA for the beta(A)- and beta(B)-subunits in the endosalpinx. These results indicate that the endosalpinx is able to synthesize activin, not inhibin, suggesting that in premenopausal women they may have an important role in the biology of the developing embryo. The role in postmenopausal women is less certain, but could lead to the stimulation of FSH secretion by the pituitary gland or other autocrine/paracrine function within the uterine tube.

The expression of secretory leukocyte protease inhibitor (SLPI) in the fallopian tube: SLPI protects the acrosome reaction of sperm from inhibitory effects of elastase

BACKGROUND

Secretory leukocyte protease inhibitor (SLPI) is a protein found in various fluids, including parotid secretions, cervical mucus, seminal plasma and ascites, and is a potent inhibitor of human leukocyte elastase activity. The objective of the study was 2-fold, to evaluate (i) the presence of SLPI in the Fallopian tube, and (ii) the effect of SLPI on the acrosome reaction of sperm.

METHODS AND RESULTS

Western blot analysis revealed that SLPI protein was detected as a 12 kDa band in the isthmus, ampulla and infundibulum of the Fallopian tube. Immunohistochemistry using an anti-SLPI polyclonal antibody revealed positive staining of epithelial cells in the Fallopian tube. RT-PCR demonstrated that SLPI transcripts were expressed in the Fallopian tube. To determine the function of SLPI in the Fallopian tube, the effects of SLPI and elastase on the sperm acrosome reaction were examined. SLPI prevented the reduction of the acrosome reaction by elastase in a dose-dependent manner.

CONCLUSION

The present findings suggest that SLPI in the Fallopian tube contributes to sperm-oocyte interaction.

Immunolocalization of retinol-binding protein, cellular retinoic acid-binding protein I and retinoid X receptor beta in the porcine reproductive tract during the oestrous cycle

Retinoid-binding proteins and nuclear receptors are expressed in the reproductive tissues of different species and their expression is hormonally regulated. In the present study, we demonstrated immunocytochemically the temporal and spatial localization of retinol-binding protein (RBP), cellular retinoic acid-binding protein I (CRABPI) and retinoid X receptor beta (RXRbeta) in porcine ovary, oviduct and uterus during the oestrous cycle. RBP and CRABPI were localized in the cytoplasm, whereas RXRbeta occurred in the nucleus. RBP was not detected in either the ovary or the oviduct at any stage of the oestrous cycle. CRABPI was present in luteal cells of the ovary only during dioestrus and in glandular and ciliated cells of the oviduct during oestrus. In the ovary, RXRbeta was always present in granulosa cells and germinal epithelium, with highest levels observed during oestrus. In the uterus, RXRbeta was present throughout the cycle in both the endometrium and the myometrium. However, changes in RXRbeta were observed in the endometrium, with highest levels observed during dioestrus. RBP and CRABPI could be observed in the endometrium only during dioestrus. The results show that the occurrence of retinoid-binding proteins and nuclear receptors in individual tissues of the reproductive tract are strongly dependent on the stage of the oestrous cycle. In the oviduct, the expression of CRABPI seems to be dependent on oestrogen, whereas in the uterus the expression of RBP and CRABPI is influenced by progesterone. The association of expression in different sections of the reproductive tissues investigated shows that the presence of specific proteins involved in retinoid metabolism was dependent on events associated with ovulation, the migration of the oocyte through the oviduct and the possible implantation of the blastocyst into the uterus.

Formation of a reservoir of sperm in the oviduct

A reservoir of sperm in the initial segment of the oviduct has been found in several species of domestic and laboratory mammals. Evidently, the reservoir serves to ensure successful fertilization by providing the appropriate number of sperm in the appropriate physiological state for fertilizing oocytes soon after they enter the oviduct. Recent evidence indicates that sperm are trapped in the reservoir by binding to specific carbohydrate moieties on the surface of the mucosal epithelium of the oviduct. A bovine seminal plasma protein has been identified that associates with sperm and confers on them the capacity to bind to the carbohydrate moiety.

Circadian clockwork genes are expressed in the reproductive tract and conceptus of the early pregnant mouse

Circadian genes are expressed in some peripheral tissues, but the expression status of the female reproductive tract and the conceptus over the preimplantation period is unknown. Oocytes, uterine, oviducal tissues and preimplantation conceptuses from days 1-4 of mouse pregnancy were analysed for transcript presence by reverse transcription polymerase chain reaction. Transcripts encoded by the seven known mammalian canonical circadian genes (Per1-3, Cry1-2, Bmal1 and Clock), plus the mammalian genetic homologue of the Drosophila canonical gene Timeless, were detected in the uteri and oviducts taken from mice on days 1-4 of pregnancy and in unfertilized oocytes. After fertilization, transcripts for Per1, Cry1, Bmal1, Clock and Tim have been detected unambiguously. Transcript levels for each of these five genes fall at the two-cell stage, but are restored rapidly for Per1, Cry1 and Bmal1, presumptively by zygotic gene expression. In contrast, transcripts for Clock and Tim recover more slowly. It is concluded that circadian genes are expressed, and may therefore have a role, during the early development of the mammal.

Regulation of the expression and bioactivation of the epidermal growth factor receptor system by estradiol in pig oviduct and endometrium

Growth factors, such as epidermal growth factor (EGF), have been suggested to mediate local effects of steroid hormones within female reproductive tissue. In the present study, the influence of estrogen on the expression and bioactivity of the EGF receptor (EGF-R) system was investigated in pigs. Oviducal and endometrial tissue from gilts was analysed either at two different time points after ovulation (Day 12 and Day 20), or from ovariectomized animals, with or without steroid-replacement treatment. Estrogen receptor protein concentrations were significantly down-regulated both in oviducal and endometrial tissue under estrogen-influence, in contrast to increased progesterone receptor concentrations. Transcript levels of EGF and transforming growth factor alpha remained unchanged in both the oviduct and endometrium during treatment. Oviducal EGF-R mRNA was found to be increased after estradiol treatment with concurrent increases in EGF-R protein. However, in endometrial tissue of estradiol-substituted ovariectomized pigs, the receptor transcript was significantly reduced, indicating a different regulation of EGF-R transcription within the endometrium. The bioactivity of the EGF-R, analysed by tyrosine kinase assays, was preserved throughout experiments in the porcine oviduct and endometrium without obvious changes caused by the steroids. In conclusion, estradiol may play a key role during the proliferation and differentiation of porcine oviducal tissue by activating the important paracrine or autocrine EGF system through its receptor. The cell-specific influence of progesterone during regulation of the EGF-R expression in the endometrium requires further investigation.

Ultrastructural and immunohistochemical study of the basal apparatus of solitary cilia in the human oviduct epithelium

The basal apparatus of the solitary cilium is composed of the basal body, an associated centriole and the basal body-associated structures. To see the connection between the basal body and the centriole, we studied the basal apparatus of solitary cilia in human oviductal secretory cells by electron microscopy and immunohistochemistry. A single centriole was present in the vicinity of the basal body of a solitary cilium. The basal body and the single centriole were interconnected by one or two bundles of thin filaments with a few periodic striations. We have called these bundles the striated connector. The periodicity of striations in the striated connector measured 55 +/- 6 nm, about 15 nm shorter than that of striated rootlets. The striated connector was immunolabelled with R67 antibody specific to striated rootlets, indicating that they are composed of common molecule(s). Although the true function of the connector is unknown as yet, it could play an important role for stabilising the basal body in the apical cytoplasm.

Polyp of the fallopian tube

The case of a 34-year-old woman who had a radical hysterectomy for stage 1 b squamous cell carcinoma of the cervix and in whom an epithelial polyp was identified in the left fallopian tube is presented. The case is unusual in that the polyp developed in the absence of any evidence of tubal damage as demonstrated by a history of endometriosis or tubal sterilisation.

Nongonadal LH/hCG receptors in pig: functional importance and parallels to human

Luteinizing hormone (LH) and human chorionic gonadotropin (hCG) share a common receptor in gonadal cells; however, the presence of these receptors has also been detected in several nongonadal but reproduction-associated tissues of pig, human, and other species. There are no data about the ontogeny of the human LH/hCG receptor. The expression of the porcine LH receptor gene in the uterus starts about 10 days after the appearance of this gene in gonads. LH/hCG receptors were found in uterus (myometrium, endometrium), oviduct, cervix, fetal membranes, and umbilical cord in humans and pigs. The main role of LH/hCG receptors in myometrium is stimulation of growth and hyperplasia and relaxation of uterine motility. hCG also increases blood flow in the uterine artery. LH and hCG can increase production of prostaglandins in endometrium, oviduct, and blood vessels. It is suggested that the preovulatory surge of LH plays an important role in controlling oviductal contractions. Human and pig mammary glands also possess LH/hCG receptors through which gonadotropins can affect the metabolism of steroid hormones in this tissue and may play an inhibitory role in mammary carcinogenesis and in the growth of breast tumors.

PAF receptor and PAF acetylhydrolase expression in the endosalpinx of the human Fallopian tube: possible role of embryo-derived PAF in the control of embryo transport to the uterus

BACKGROUND

Prostaglandin-E(2) and platelet-activating factor (PAF) are embryonic-derived signals that time embryo passage into the uterus in the mare and hamster respectively. PAF-like activity is detectable in the spent media of preimplantation human embryos and it has been suggested that PAF may be the embryonic signal that controls embryo transport to the uterus in our species. The actions of PAF are regulated at the level of its synthesis and degradation as well as the expression of a specific cell surface receptor (PAFr). The enzyme PAF acetylhydrolase (PAF-AH) degrades PAF. This study was undertaken to examine whether or not PAFr and PAF-AH are expressed in the human Fallopian tube and to identify the cell types in which they are expressed.

METHODS

The presence of PAFr mRNA in tissue extracts was investigated using reverse transcription-polymerase chain reaction. We amplified the predicted amplicon for PAFr mRNA from RNA samples extracted from Fallopian tubes. The expression of PAF-AH was detected by Western blot and the localization of PAFr and PAF-AH proteins was detected by immunohistochemistry.

RESULTS

Utilizing antibodies against PAFr and PAF-AH, co-localization of the two proteins in the epithelium and stromal cells were demonstrated.

CONCLUSIONS

These observations show that the human Fallopian tube expresses PAFr and PAF-AH at a location compatible with the proposed paracrine role of early embryo-derived PAF.

Differential expression of extracellular matrix components in the bovine oviduct during the oestrous cycle

Components of the extracellular matrix take part in tissue rebuilding as well as activating surface-bound growth factors. In the present study, expression and selected activities of urokinase-type plasminogen activator (uPA), matrix metalloproteinases (MMPs), their inhibitors (plasminogen activator inhibitor 1 (PAI-1) and tissue inhibitors of metalloproteinases (TIMPs)) were examined in bovine oviducts by RT--PCR, ribonuclease protection assay and activity assays. A high content of mRNA encoding for uPA was detected before ovulation with a three-fold decrease after ovulation. In contrast, PAI-1 expression appeared to be stable during the oestrous cycle. Oviductal flushings produced caseinolytic zones in zymograms containing plasminogen at approximately 50 kDa and 28 kDa. An activity assay for uPA showed highest net activity during the early to mid-luteal phase. Increased TIMP-1 and MMP-2 mRNA concentrations were found around the time of ovulation compared with the luteal phase. In contrast, MMP-1 mRNA transcripts were enriched during the early to mid-luteal phase. Gelatin zymograms detected a 70--72 kDa protease activity showing an oestrous cycle-dependent activity with highest activity before ovulation. Reverse zymography detecting TIMPs revealed proteins between 21 kDa and 24 kDa. Only for the smallest (21 kDa) protein were amounts increased around the time of ovulation compared with the luteal phase. The observation that several extracellular matrix components were regulated distinctly in bovine oviducts indicates that local interactions between these components, growth factors, gametes and the embryo are possible and may influence fertilization and early embryonic development.

Immunohistochemical localization of estrogen receptor-alpha in sex ducts and gonads of newborn piglets

Estrogen receptor-alpha (ER-alpha) expression in piglet uteri has previously been reported from day 15 after birth. Nevertheless, uterine tissue has been reported to be estrogen sensitive from the day of birth. Since estrogen action in the uterine tissue is suggested to be mediated principally by ER-alpha, the present study aimed to evaluate the presence of ER-alpha in uteri of 1- to 2-day-old piglets by means of immunohistochemistry. In addition, sex ducts and gonads of both sexes were examined. The results clearly demonstrate the presence of ER-alpha immunopositive cells in uterine tissue, which explains its estrogen responsiveness. Immunostaining was most intense in the glandular epithelial cells and is suggested to indicate participation of ER-alpha in adenogenesis. In oviducts, almost all epithelial cells were immunostained moderately positive, while the stroma cells were stained comparably more positive. The functional significance of this intensity difference is uncertain but could indicate that part of the estrogen action on the epithelium is mediated through the stroma cells, as is known for the uterus. In ovaries, the surface epithelium and stroma cells were immunostained, whereas germ and granulosa cells were immunonegative. It is speculated that ER-alpha might be involved in yet unknown intraovarian mechanisms. In male sex ducts, immunostaining was virtually confined to the epithelium of efferent ducts. All cells in the epididymis as well as in vas deferens were immunonegative. The unique presence of ER-alpha in efferent ducts corresponds with localization in other species, where it has been shown to be involved in fluid reabsorption. The obtained data on localization of ER-alpha correspond with the present knowledge, obtained in ER-alpha knockout mice, of the biological function of ER-alpha within male and female gonads and sex ducts.

Differential expression of TGF-beta1 and TGF-beta3 in serosal tissues of human intraperitoneal organs and peritoneal adhesions

Elevated local expression of transforming growth factor (TGF-beta) has been associated with increased incidence of peritoneal adhesion formation. In this study we determine whether differences in basal expression of TGF-beta in serosal tissue of peritoneal organs correlate with incidence of adhesion formation. Serosal tissue of parietal peritoneum, uterus, oviduct, ovary, omentum, large and small bowels as well as adhesions, skin, fascia, subcutaneous tissue, peritoneal fluid and serum were collected from 57 subjects with/without adhesions who were undergoing abdominal/pelvic surgery. To determine TGF-beta1 and TGF-beta3 mRNA and protein expression, total RNA and protein were isolated from these tissues and along with the fluids, subjected to quantitative RT-PCR and enzyme-linked immunosorbent assay (ELISA) respectively. Tissue sections were immunostained for TGF-beta1 and TGF-beta3 protein. We found that TGF-beta1 and TGF-beta3 mRNA and protein are expressed in these tissues and present in peritoneal fluids and serum, with considerable variations in level of their expression. Comparatively, there was more variation in TGF-beta1 than TGF-beta3 expression without age or gender relation. Adhesions express a significantly higher TGF-beta1 mRNA and have the highest TGF-beta1:TGF-beta3 ratio, with lowest concentrations and ratio detected in omentum, small and large bowels; in contrast uterus expresses higher TGF-beta3, with lowest concentrations detected in subcutaneous tissue and large bowels (P < 0.05). A similar trend was also observed for total (active + latent) TGF-beta1 protein expression, with low active TGF-beta1 that was not significantly different among the tissue extracts and fluids. However, the lowest active:total TGF-beta1 ratio was found in adhesions and ovary. In subjects with adhesions, the adhesions express significantly more TGF-beta1 compared to parietal peritoneum (P < 0.05). Immunoreactive TGF-beta1 and TGF-beta3 protein were present in various cell types in these tissues with intensity reflecting their mRNA and protein expression. In conclusion, we provided evidence that serosal tissue of various peritoneal organs and adhesions express TGF-beta1 and TGF-beta3. Since TGF-beta is expressed differently in these tissues and tissue injury often alters the expression of TGF-beta, we propose that tissues with a higher basal expression of TGF-beta may become predisposed to develop more adhesions compared to others.

Langerhans cells in the human oviduct mucosa

Langerhans cells (LCs) are the predominant antigen-presenting cells in epithelial tissues. They have been known to be present in the vagina and uterine cervix. In the present study, localization of LCs in the oviduct was investigated by electron microscopy and immunohistochemistry using an anti-CD1a (CD; cluster of differentiation) antibody. Although the cell density was variable, CD1a-positive LCs were detected in the oviduct epithelium. Their occurrence was most common in women at the age of 40 to 59. LCs extended cell processes along the base of the epithelium and were ultrastructurally characterized by rod-shaped Birbeck granules and a well-developed Golgi apparatus. LCs, together with lymphocytes and macrophages, are considered to engage in the mucosal immune system of the oviduct.

Myofibroblasts in the mucosal layer of the uterine tube

Uterine tubes from cow, sheep, horse, pig, dog, cat, rabbit, and guinea pig were examined immunohistochemically for presence and distribution of contractile cells in the mucosal lamina propria. We tested for the presence of alpha-smooth muscle actin, tropomyosin, desmin, smooth muscle myosin (heavy chain) and cytoskeletal proteins vimentin and cytokeratin. Immunostaining for alpha-smooth muscle actin showed two distribution patterns: either positive cells were freely dispersed in the mucosal lamina propria or a distinct subepithelial layer of positive cells was seen. The first distribution pattern was found in the isthmic uterine tube segments of all animals examined. Alpha-smooth muscle actin was colocalized with tropomyosin (all species), desmin (horse, sheep), and smooth muscle myosin (sheep, cow). All these cells were found reactive with anti-vimentin but not with anticytokeratin and therefore were classified as myofibroblasts. A distinct subepithelial layer of alpha-actin and tropomyosin positive cells was seen in horse fimbriae. In other examined species alpha-smooth muscle actin immunoreactivity in the subepithelial region was very weak. Contractile cells in the uterine tube mucosa were supposed to influence mucosal condition and motility, and therefore to play a role in gamete transport.

Muc1 and glycan expression in the oviduct and endometrium of a New World monkey, Cebus apella

Cebus apella is a New World monkey that has a menstrual cycle of 18-23 days with implantation at approximately luteal Day 5. The aim of this study was to characterize by lectin- and antibody-labeling the distribution of Muc1 and associated glycans on the endometrial and oviductal epithelium during the luteal phase of the cycle. Endometrial histology showed a thin endometrium, with glands extending deeply into the myometrium. No obvious evidence of secretory differentiation in cells of either the superficial or the basal segments of glands could be obtained using a panel of antibodies and lectins that marked epithelial glycoprotein, and glycosylation changes observed in some other primate endometrial cycles were not observed in this study. Antibodies to human MUC1 were shown to cross-react with C. apella, and Muc1 was localized to the apical epithelial surfaces of both the endometrial and the tubal epithelium, with stronger expression in the latter. Again, no cyclic changes were noted. Antibodies specific to the isoform Muc1/Sec showed strong staining at the apical tubal epithelium, but no reactivity was detectable in the luminal epithelium of the uterus. This observation suggests differences between the two glycocalyces and could help to explain why C. apella embryos do not implant in this location.

Carbohydrate-mediated formation of the oviductal sperm reservoir in mammals

Mammalian sperm are trapped in a reservoir in the oviduct until ovulation is imminent. Then, they are gradually released, such that a few meet the oocytes as they enter the ampulla of the oviduct. In the three eutherian species studied to date, sperm are trapped in the reservoir by carbohydrate-mediated binding to the oviductal mucosa. Evidence indicates that a molecule on the surface of the plasma membrane overlying the acrosome binds to a carbohydrate moiety on the surface of the oviduct. While sperm remain bound, they appear to be protected from degradation. When sperm become capacitated, they lose binding affinity for the oviductal mucosa. The mechanism initiating capacitation in the reservoir is unknown; however, it must be tied to the hormonal signalling of ovulation. Hyperactivated motility may assist sperm in pulling off from the mucosal surface as binding affinity declines. The function of the reservoir appears to be to prevent polyspermy and ensure fertilization by providing a small number of sperm in the proper physiological condition for fertilization at the time the oocytes enter the oviduct.

Localization and distribution of platelet activating factor receptors in the mouse ovary and oviduct during the estrous cycle and early pregnancy

PROBLEM

This study determined platelet activating factor (PAF) binding to ovaries and oviduct tissues to identify the location of PAF tissue interaction.

METHOD

Mouse ovaries and oviducts taken during the estrous cycle and days 1, 4 and 7 post-conception (pc) were analyzed by [3H]PAF binding using frozen sections and autoradiography.

RESULTS

For the outer epithelium of estrous and metestrous ovaries there was no significant difference in PAF binding (P>0.05); however, both stages were significantly different from proestrous (P<0.001). Ovarian stroma PAF binding was significantly higher (P<0.001) at estrous than metestrous, with no PAF binding at proestrous. Binding of PAF to estrous ovarian follicles was significantly greater (P<0.001) than at proestrous and metestrous. Estrous oviduct binding of PAF was significantly increased for stroma, inner epithelium and lumen (P<0.001 in all cases). At days 1 and 7 pc, all ovarian tissues had the greatest PAF binding with day 4 pc failing to bind PAF except for a significant decrease in corpora luteal binding (P<0.001). Oviduct binding of PAF was greatest at day 1 pc.

CONCLUSION

Ovarian and oviduct PAF receptor expression corresponds to peak embryo PAF synthesis and establishes the basis for PAF PAF receptor mediated early pregnancy signaling system.

Tubal versus uterine placentation: similar HLA-G expressing extravillous cytotrophoblast invasion but different maternal leukocyte recruitment

The nonclassical HLA-G class I gene is expressed by extravillous cytotrophoblast that invades decidua in uterine pregnancy, suggesting that it may contribute to the immunological mechanisms that protect the fetus against maternal alloimmune response and/or pathogen infections. We first addressed the question of whether HLA-G expression was dependent on maternal tissue environment by comparing uterine and ectopic tubal pregnancies. Using HLA-G-specific mAb on placental cryosections, we found by immunohistochemistry that all subtypes of extravillous cytotrophoblast similarly expressed HLA-G in pregnant tubes, demonstrating that its expression was independent of the site of implantation. We next compared by immunohistochemistry the phenotype of maternal leukocytes recruited in both pregnant tissues. In contrast to decidua, pregnant tubes were characterized firstly, by the lack of natural killer (NK) cells and of cells expressing CD94 receptor specific for HLA-E, secondly, by a prominent increase of CD8+ T cells, dendritic cells, and macrophages, the latter co-expressing the LIR1/ILT2 killer immunoglobulin-like receptor (KIR), and finally, by the presence of cells expressing LIR2/ILT4 KIR or BY55 NK receptors, known to bind to HLA-G. Such cell types may favor a unique innate defense in pregnant tubes. These observations also suggest that trophoblast HLA-G expression does not influence the recruitment of particular maternal leukocytes in pregnant tissues.

High insulin-like growth factor 1 (IGF-1) and insulin concentrations trigger apoptosis in the mouse blastocyst via down-regulation of the IGF-1 receptor

Women with polycystic ovary syndrome have significantly higher rates of pregnancy loss, as well as elevated insulin and IGF-1 levels. In this study, preimplantation embryos exposed to high concentrations of IGF-1 or insulin undergo extensive apoptosis of the ICM nuclei. Lack of BAX expression, the caspase inhibitor, zVAD, or the ceramide synthase inhibitor, fumonisin B1, prevents this event, suggesting involvement of programmed cell death effector pathways. In other systems, the IGF-1 concentration regulates IGF-1R expression and thus high concentrations lead to down-regulation of the receptor. Here, data show a decrease in IGF-1 receptor protein expression, both by confocal immunofluorescent microscopy and by Western analysis upon exposure to 130 nM IGF-1. Insulin-stimulated glucose uptake, an event regulated via the IGF-1 receptor, is decreased upon exposure to excess IGF-1, suggesting decreased function of the receptor. The data also show that, by blocking receptor signal transduction or by decreasing receptor expression, the apoptotic event can be recreated, thus strongly suggesting that the mechanism of high IGF-1 induced apoptosis is decreased downstream IGF-1 receptor signaling. This embryotoxic insult by high IGF-1 levels may be responsible for the high incidence of pregnancy loss seen in women with polycystic ovary syndrome.

Does plasminogen activator inhibitor-1 (PAI-1) control trophoblast invasion? A study of fetal and maternal tissue in intrauterine, tubal and molar pregnancies

Urokinase plasminogen activator, its receptor and the inhibitor PAI-1 are believed to control proteolysis and remodelling of maternal tissue during trophoblast invasion. This system appears to be strictly regulated in normal intrauterine pregnancies whereas tubal and molar pregnancies seem to be characterized by an uncontrolled excessive placental invasion. This study evaluates subcellular PAI-1 by immunohistochemistry in the villous placenta, in the basal plate and placental bed, and in the decidual compartments of normal, tubal and molar pregnancies. PAI-1 was present in villous syncytiotrophoblasts and co-localized focally with fibrin-type fibrinoid on the surface of the chorionic villi. Basal plate and placental bed extravillous interstitial trophoblasts, as well as vascular trophoblasts, were also PAI-1 positive. In the decidua parietalis, PAI-1 was observed in the cytoplasm of the non-invaded decidual cells. In the decidua basalis comprising the basal plate, PAI-1 was seen to be membrane-associated or confined to the extracellular matrix (ECM) facing the invasive front of anchoring villi. The ECM of decidua capsularis and chorion laeve displayed the most pronounced PAI-1 expression towards the maternal interface. In contrast, the majority of placental bed decidual cells adjacent to the interstitial and vascular trophoblasts were PAI-1 negative. Only a few stromal cells distant from the implantation site were PAI-1 positive in the tubal pregnancies and decidualization was not present. Likewise, excessive decidual necrosis and fibrinoid deposition devoid of PAI-1 was a common finding in complete molar pregnancies. These results suggest that PAI-1 defines specific extravillous invasive trophoblasts within the maternal decidua. Moreover, maternal cellular lack of PAI-1 in tubal pregnancies and excessive decidual necrosis in molar pregnancies indicate an uncontrolled placental invasion. The present data indicate that trophoblast invasion is primarily regulated by signals from decidual cells.

Constitutive expression of heat shock proteins hsp25 and hsp70 in the rat oviduct during neonatal development, the oestrous cycle and early pregnancy

Certain heat shock proteins are regulated by steroid hormones and are associated with oestrogen receptor function in reproductive tissues, indicating that these proteins have a role during implantation, decidualization and placentation. In the present study, the expression of hsp25, hsp70 and oestrogen receptor alpha were examined by immunohistochemistry in oviducts from rats during neonatal development, the oestrous cycle and during early pregnancy. Oestrogen receptor alpha was the first protein observed in the neonatal oviduct, and its expression preceded that of hsp70 and hsp25. Although these heat shock proteins have been associated with the oestrogen receptor, this study showed that during early development of the oviduct, the receptor protein was not associated with the concomitant expression of hsp25 and hsp70. However, these heat shock proteins were expressed when oviductal cells became differentiated. In the adult oviduct, hsp70 was more abundant than hsp25, moreover, there were no significant modifications in expression of hsp25 during the oestrous cycle. In contrast, the expression of hsp70 was significantly higher in epithelial cells during dioestrus, when the maximum amount of oestrogen receptor alpha was also observed. Therefore, the present study shows that hsp70, but not hsp25, is an oviductal protein modulated by the oestrous cycle and that it is a protein marker for specific phases of the oestrous cycle. In addition, hsp70 was more responsive to the hormonal changes in the infundibulum and ampullar regions of the oviduct. During early pregnancy, hsp25 expression was downregulated (unlike in the endometrium), whereas hsp70 was relatively abundant in the oviduct. hsp70 was observed in all functional segments of the oviduct during pregnancy, indicating that in the oviduct, this protein is modulated by oestrogens and progesterone and possibly by other pregnancy-related hormones.

Distribution and cytological properties of macrophages in human Fallopian tubes

The macrophages in human Fallopian tubes of women in the reproductive and postmenopausal periods were examined with a focus on their morphological properties by immunohistochemical staining and transmission electron microscopy. The fine structure of the smooth muscle cells in the Fallopian tubes was also investigated during the reproductive period. For immunohistochemical staining, we used two monoclonal antibodies that were specific for human macrophages, namely PM-1K and PM-2K. PM-1K recognizes human monocytes/ macrophages corresponding to CD68, and PM-2K recognizes tissue macrophages. PM-1K-positive cells were always present and their numbers increased significantly during the menstrual and early to mid-secretory phases. In contrast, relative numbers of PM-2K-positive cells were small throughout the menstrual cycle. In the postmenopausal period, few PM-1K-positive cells were detected, but PM-2K-positive cells remained. The macrophages during the secretory phase in the endosalpingeal stroma had well-developed intracytoplasmic organelles, but relatively few cytoplasmic vacuoles and granules. In the same phase, many cells of the monocyte/macrophage lineage appeared in the vascular lumen of the endosalpingeal stroma. The macrophages during the menstrual phase had well-developed intracellular organelles, with cytoplasmic vacuoles and granules of various sizes and configurations. During the late secretory phase, just prior to menstruation, the smooth muscle cells contained few cytoplasmic filaments but electron-lucent or electron-dense lysosome-like bodies were seen. These findings suggested the presence of macrophages in human Fallopian tubes. It is possible that such macrophages might be involved in the physiological functions of the tubes during the reproductive period and moreover that they might participate in the reconstruction of the muscle layer of the tubes.

Expression of intercellular adhesion molecule 1 (ICAM-1) on the human oviductal epithelium and mediation of lymphoid cell adherence

The epithelium of the human oviduct expresses the major histocompatibility complex (MHC) class II and shows endocytic properties towards luminal antigens. Therefore, the epithelial cells might behave as antigen-presenting cells, inducing a local immune response. The activation of antigen-specific T cells not only requires presentation of the peptide antigen by MHC class II, but also the presence of co-stimulatory molecules in the antigen-presenting cells. Therefore, the expression of the intercellular adhesion molecule 1 (ICAM-1) was examined in the epithelium of the human oviduct. Most oviducts showed epithelial ICAM-1 expression, as assessed by immunocytochemistry, western blot analysis and RT-PCR assay, and the expression was restricted to the luminal border of ciliated and secretory cells. Interferon gamma, interleukin 1 and lipopolysaccharide treatments increased the percentage of ICAM-1-positive cells in primary cultures, indicating that the expression of ICAM-1 in the oviduct might be upregulated in vivo by inflammatory cytokines or bacterial infections. Binding assays between allogenic phytohaemagglutinin-activated lymphocytes and epithelial monolayers expressing ICAM-1 demonstrated that this molecule stimulated lymphocyte adherence. The presence of ICAM-1, in addition to MHC class II, supports the putative role of the oviductal epithelium in antigen presentation. The exclusive apical distribution of ICAM-1 indicates that T-cell activation would occur in a polarized manner. Binding of lymphoid cells to the surface of the oviductal epithelium may help to retain these immune cells that are required for the clearance of pathogens.

Expression of vasoactive intestinal peptide (VIP) receptors in human uterus

We show the existence of functional vasoactive intestinal peptide (VIP) receptors in normal human female genital tract (endometrium, myometrium, ovary and Fallopian tube) as well as in leiomyoma (a frequent uterine pathology). The correlation between VIP binding and stimulation of adenylyl cyclase activity for all studied tissues was linear (r = 0.86) suggesting the expression of VIP receptors throughout the human female genital tract. Immunodetection of VIP receptor subtypes gave different molecular weights for VPAC(1) (47 kDa primarily) and VPAC(2) (65 kDa), which may be due to different glycosylation extents. In conclusion, this study demonstrates the expression of both subtypes of VIP receptors and their functionality in human female genital tract, suggesting that this neuropeptide could play an important physiological and pathophysiological role at this level.

Immunocytochemistry of the striated rootlets associated with solitary cilia in human oviductal secretory cells

The human oviduct epithelium is a simple columnar structure that consists primarily of ciliated and secretory cells. Solitary cilia usually extend from the apical cell surface of secretory cells. By injecting crude preparations of striated rootlets into rats, we successfully obtained six monoclonal antibodies (R38, R67, R95, R149, R155, R213) that commonly labeled ciliary rootlets. Using these antibodies, proteins of 205-215 kDa were identified by immunoblotting. Using a clone, R67, we investigated the morphology of the striated rootlets associated with solitary cilia by immunocytochemistry. It was found that the shapes of the rootlets were not simple but varied considerably. The rootlets had branched, radiated, arched, and looped shapes. This is the first report of the rootlets having a variety of shapes. The 205- to 215-kDa antigens identified by the six different antibodies were mostly localized to dark bands of striations, suggesting that they are constitutive components of dark striations of the rootlet.

[Determination of tumor necrosis factor-alpha and interleukin-6 levels of the tubal fluids in patients with infertility caused by infection of Chlamydia trachomatis]

OBJECTIVE

To study the levels of tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) in tubal fluids of tubal factor infertile (TFI) women due to chlamydia trachomatis (CT) infection and its implication.

METHODS

Twenty-two TFI women with CT infection (group A), twenty-three TFI women without CT infection (group B) and nineteen fertile women with normal tubes (group control) were enrolled for study. Levels of TNF-alpha and IL-6 in tubal fluids were measured by enzyme-linked immunosorbent assay.

RESULTS

Group A had significantly higher TNF-alpha levels than those of group control (178 ng/L versus 124 ng/L, P < 0.01). Moreover, women with tubal blocks had significantly higher TNF-alpha those of tubal adhesions (199 ng/L versus 142 ng/L, P < 0.01). IL-6 levels of group A were significantly higher than those of group B and group control (681 ng/L versus 264 ng/L and 229 ng/L, both P < 0.01), but there is no difference between group B and group control.

CONCLUSIONS

Local TNF-alpha and IL-6 levels increased in silent tubal infection of CT. TNF-alpha had a positive relevance with the degree of tubal damage.

Preparation of a monoclonal antibody specific for the class I isotype of beta-tubulin: the beta isotypes of tubulin differ in their cellular distributions within human tissues

Tubulin, the subunit protein of microtubules, is an alpha/beta heterodimer. In many organisms, both alpha and beta consist of various isotypes. Although the isotypes differ in their tissue distributions, the question of whether the isotypes perform different functions in vivo is unanswered. In mammals, the betaI and betaIV isotypes are quite widespread, and betaII is less so, while betaIII and betaVI have narrow distributions and betaV distribution is unknown. As a tool for localizing the isotypes, we report the preparation of a monoclonal antibody specific for betaI, to add to our previously described monoclonal antibodies specific for betaII, betaIII, and betaIV [Banerjee et al., J. Biol. Chem. 263:3029-3034, 1988; 265:1794-1799, 1990; 267:5625-5630, 1992]. In order to prepare this antibody, we have purified betaI-rich rat thymus tubulin. We have used our battery of antibodies to localize the beta isotypes in four human tissues: oviduct, skin, colon, and pancreas. We have found striking differences in their tissue distributions. There is little or no betaIII in these tissues, except for the columnar epithelial cells of the colon. BetaII is restricted to very few cells, except in the skin, where it is concentrated in the stratum granulosum. BetaI is widespread in all the epithelia. In the skin it is found in the entire stratum malpighii. In the oviduct, betaI is found largely in the nonciliated epithelial cells. In the exocrine pancreas, betaI occurs only in the centroacinar cells and not in the acinar cells; the latter do not stain with any of these antibodies. BetaIV is present at very low levels in skin and pancreas. By contrast, it is prominent in the colon and also in the oviduct, where it occurs in all the epithelial cells, especially in the ciliated cells, with the highest concentrations in the cilia themselves. These results suggest that the regulation of the expression and localization of isotypes in tissues is very complex.

An immunohistochemical study of the rete ovarii and epoophoron

A study to compare the immuno-histochemical profile of the human rete ovarii, and epoophoron, with the Fallopian tube and ovarian surface epithelium was performed with 31 antibodies and antisera. A reaction was present in the epithelial cytoplasm of the rete ovarii and epoophoron of mesonephric origin, for vimentin, GFAP, cytokeratin markers, (AE1/AE3, MNF116; Cam 5.2, 34 beta E12 and for the monospecific antibodies to cytokeratins 7 and 19), heat shock protein 27, in the cell membrane for HBME-1, EMA and in the subepithelial collagen for collagen IV. Reactions were present only in the epithelium in the rete ovarii for EGFR (one case) and CA-125 (four cases). A reaction was present in the epithelium of the epoophoron only for Ber-EP-4 and S100. There was no reaction with antibodies for desmin, neurofilament protein, cytokeratins 20 or 14, actin, calretinin, E-cadherin, C-erb-B2, or CEA (monoclonal and polyclonal reagents). The immuno-histochemical profile of the Fallopian tube was consistent with its para-mesonephric origin and that in the ovarian surface epithelium was consistent with a proposed modified mesothelial origin. This study provides an immunohistochemical profile of these structures with a large panel of commonly available antibodies and antisera, confirming and extending the findings described in previous studies.

Localization of oestrogen receptor alpha, oestrogen receptor beta and androgen receptors in the rat reproductive organs

There is now evidence that oestrogens and androgens can influence male and female reproductive systems. In order to accurately identify the sites of action of oestrogens and androgens, we have proceeded to the histological localization of the two oestrogen receptor (ER) subtypes, ERalpha and ERbeta, and the androgen receptor (AR) in the reproductive tissues of adult rats of both sexes. AR was detected by immunocytochemistry, while ERalpha and ERbeta were localized by both immunocytochemistry and in situ hybridization. In the pituitary gland of animals of both sexes, ERalpha was found in the majority of nuclei of secretory cells in the anterior pituitary. The intermediate and posterior lobes did not show any staining. ERbeta was not found to be expressed in any of the pituitary lobes. Using AR antibodies, nuclear staining was detected in about 50% of secretory cells of the anterior lobe, the intermediate and posterior lobes being completely unstained. In the testis, ERalpha was localized in nuclei of Leydig cells as well as in round spermatocytes and spermatids, while ERbeta could only be detected in Sertoli cell nuclei. AR immunoreactivity was found in nuclei of Sertoli, peritubular myoid and Leydig cells. In the prostate, ERbeta was observed in epithelial cells of tubulo-alveoli, while the stroma was unlabelled. ERalpha was not found to be expressed in any prostate cells. In the prostate, AR was detected in nuclei of epithelial, stromal and endothelial cells. In seminal vesicles, staining of ERalpha was found in nuclei of epithelial and stromal cells. Similar findings were observed using AR antibodies. While ERbeta mRNA could not be detected by in situ hybridization, weak staining for ERbeta was localized in epithelial cells of seminal vesicles. In the ovary, both ERalpha and ERbeta were found to be expressed. ERbeta mRNA was found in granulosa cells of growing follicles, while ERalpha was present in theca cells, interstitial gland cells and germinal epithelium. AR immunoreactivity was detected in granulosa cell nuclei in growing follicles and also in scattered interstitial cells. In the oviduct and uterus, ERalpha was observed in nuclei of epithelial cells as well as of stromal and muscle cells. Similarly, AR immunoreactivity was present in nuclei of epithelial cells, stromal and muscle cells in both the oviduct and uterus. ERbeta was not detected in the oviduct and uterus. The present findings indicate a cell-specific localization of ERalpha, ERbeta and AR in reproductive tissues in rats of both sexes. By establishing the precise sites of action of oestrogens and androgens they contribute to a better understanding of the respective role of these steroids in reproduction function.

Human oviductal gonadotropin-releasing hormone: possible implications in fertilization, early embryonic development, and implantation

The oviduct is host to gametes and early embryos at a critical point in their lives. It is clear that the interactions of gametes/early embryo with the maternal oviduct in an autocrine and paracrine manner provide a microenvironment that enhances fertilization, early embryonic development, and implantation. Moreover, there is considerable evidence that an extrahypothalamic GnRH may play a substantial role as a molecular autocrine/paracrine regulator in these events. Gametes and preimplantation embryos express GnRH and GnRH receptor at both messenger ribonucleic acid (mRNA) and protein levels. However, whether GnRH is produced by the human oviduct has not yet been demonstrated. We used RT-PCR and immunohistochemical techniques to investigate GnRH mRNA and protein expression in human fallopian tubes throughout the menstrual cycle of premenopausal fertile patients. Our results, at both the mRNA and protein levels, revealed cycle-dependent production of an oviductal GnRH with expression during the luteal phase. Moreover, GnRH immunostaining was localized in the tubal epithelium during the luteal phase. On the basis of these data, we suggest that during reproductive life, oviductal GnRH may play a substantial paracrine/autocrine role in human fertilization, early embryonic development, and implantation.

Expression of antigens involved in the presentation of lipid antigens and induction of clonal anergy in the female reproductive tract

The molecular backgrounds of the anti-phospholipid syndrome and immunisation against the Rhesus proteolipid antigens are still largely unknown. In the present study, expression of (1) CD1, a major histocompatibility complex class l-like lipid antigen presenting molecule, (2) IL-10, a cytokine promoting induction of clonal anergy, and (3) CD80 and CD86, two T-cell costimulators preventing induction of clonal anergy when present, was investigated in frozen sections of cervix, corpus and the fallopian tube (FT) of 25-day-old BALB/c mice injected with FSH, progesterone or medium and of pregnant mice from each trimester (days 7, 14 and 19). CD1 was expressed by all endometrial epithelial cells. Enhanced immunostaining of the endometrial epithelial cells was observed after FSH treatment, and cervix and FT expressed generally more than the corpus of the uterus. After treatment with medroxy progesterone acetate (MPA), expression of CD1 by the endometrial epithelia was weak. During pregnancy CD1 was absent from the endometrium adjacent to the foetus, but was unaltered in the cervix and FT. IL-10 was expressed by the endometrial glands and also by the endometrial surface epithelium. MPA treatment increased the intensity of the IL-10 immunofluorescence. There were also chains of positive cells between the muscle bundles within the pregnant myometrium. CD80 and CD86 were usually absent from the female reproductive tract, but were occasionally found in the cervix during pregnancy. The present study demonstrates definite differences in the expression of both CD1 and IL-10 between the FSH and MPA treated mice, suggesting differences during the oestrous cycle. As IL-10 is expressed more in the secretory phase, it is probably involved in making the endometrium more acceptable for implantation by inducing clonal anergy. This is supported by the absence of CD80 and CD86. These results also suggest that abnormal expression of CD1d during pregnancy may predispose the mother for immunisation against lipid antigens such as membrane phospholipids and Rhesus-antigens.

Effects of glucose and protein sources on bovine embryo development in vitro

Oviductal factors may be obtained by ultrafiltration of conditioned medium, added to a simple media and used in bovine embryo culture. In this study, we aimed to analyze the development of bovine embryos produced with oviductal factors compared to those cultured in the presence of BSA or serum, the effects of glucose in presence of these protein supplements, and the ability of oviductal factors to support embryo development during the entire culture period. In vitro produced bovine zygotes from slaughterhouse ovaries were cultured in modified-synthetic oviduct fluid (mSOF) alone or supplemented with (1) oviductal factors, (2) BSA and (3) FCS. Oviductal factors showed embryotrophic activity, although with blastocyst rates lower than those in BSA and FCS. Glucose (1.5 mM) added at Day 2 of culture did not affect development in the presence of oviductal factors. The number of cells in expanded blastocysts was unaffected by the presence of glucose or any of the protein supplements used. Both BSA and FCS, respectively, improved blastocyst rates of Day 6 embryos produced with oviductal factors. The effect of oviductal factors was masked by the presence of BSA during the entire culture. FCS promoted an earlier appearance of blastocysts. It is concluded that the effect of glucose on in vitro embryo development depends upon the source of protein. Oviductal factors are not an appropriate supplement for embryos beyond Day 6 of culture in SOF, although blastocyst rates of such embryos may be increased by culturing them in the presence of FCS or BSA.

Effect of estradiol and progesterone on oviductal LH-receptors and LH-dependent relaxation of the porcine oviduct

We have previously shown that the porcine oviduct possesses immunoreactive and functional LH receptors and that LH causes relaxation of the oviduct, especially during the periovulatory stage of estrous cycle. The current studies were undertaken to investigate the effects of estradiol and progesterone on LH receptor protein and LH-stimulated motility of the oviduct in steroid-primed ovariectomized gilts. Twenty-one cross-bred gilts were ovariectomized at 6 m.o. of age. Four weeks later gilts received daily intramuscular injection of either 2 mL corn oil (control n = 4), estradiol benzoate (EB) 1.5 mg (n = 6), progesterone 50 mg (n = 5), or 1.5 mg EB plus 50 mg progesterone (n = 6) for 4 consecutive days. The gilts were slaughtered on Day 5 after the first injection of steroids or vehicle. Rings of isthmus and ampulla were collected from each oviduct and placed in a tissue chamber perfused with Kreb's solution for 60 min. The mechanical activity was recorded for 30 min after LH treatment. Immunoreactivity of LHR in the Fallopian tube sections were detected in the epithelium of the tubal mucosa, smooth muscle cells and the blood vessel endothelium. Western blotting showed that porcine oviducts contain 75, 48 and 45 kDa immunoreactive LH receptor proteins, like the corpus luteum (CL). The lowest receptor expression was found in controls and in gilts treated with estradiol or progesterone. Combined treatment with estradiol and progesterone resulted in a significant increase of LH receptor protein concentrations when compared with control animals. In vitro LH treatment affected oviduct contractility of combined estradiol and progesterone treated gilts but not the oviduct of the remaining groups. It also caused a decrease in amplitude, frequency and areas under the curve (AUC) of ampulla (P < 0.05) and the amplitude and AUC of isthmus (P < 0.001) in combined estradiol and progesterone-primed gilts. These results indicate that estradiol and progesterone together, but not separately, increase LH receptor protein in the porcine oviduct and that combined estradiol and progesterone priming is necessary for LH-induced relaxation of the porcine oviduct.

Induction of dog sperm capacitation by glycosaminoglycans and glycosaminoglycan amounts of oviductal and uterine fluids in bitches

Ejaculated sperm collected from 12 beagle dogs were incubated in canine capacitation medium (CCM), supplemented with 5 microg/ml chondroitin sulfate A (CS), 5 microg/ml hyaluronic acid (HA), or 5 microg/ml heparin (HP) for 7 hr at 38 degrees C in a 5% CO2 in air atmosphere to investigate the effects of glycosaminoglycans (GAGs) on dog sperm capacitation. The percentages of motile sperm, hyperactivated sperm (%HY), and acrosome-reacted sperm (%AR) in all media were examined after 4 hr and 7 hr of incubation. The oviducts and uteri of 9 anestrous and 18 estrous beagle bitches were removed under halothane inhalation anesthesia to measure the total GAG amounts in oviductal and uterine fluids. The lumens of the ampulla of the oviducts, isthmus of the oviducts, and the uterine horns were each flushed with 1 ml HEPES-EDTA fluid. Total GAG amounts in the flush fluids obtained were measured with a spectrophotometer. Sperm motility (51-59%), %HY (79-86%), and %AR (31-36%) in CCM supplemented with CS, HA, or HP were significantly higher after 7 hr of incubation than when incubated in CCM without GAGs (P<0.01 or 0.05). The mean total GAG amounts in the fluids from the ampulla and isthmus of the oviducts and the uterine horns in the estrous bitches were higher than in the anestrous bitches. These results indicate that GAGs in the oviductal and uterine fluids in estrous bitches are associated with in vivo sperm capacitation.

Sialomucin complex (Muc4) expression in the rat female reproductive tract

Previous studies in our laboratory demonstrated the presence of sialomucin complex (SMC)/Muc4 covering the rat uterine luminal epithelium. SMC/Muc4 expression in the uterus is regulated by estrogen and progesterone and lost at the time of receptivity. In contrast to this hormonal regulation at the uterine luminal surface, SMC/Muc4 in the uterine glandular epithelium, oviduct, cervix, and vagina was constitutively expressed at all stages of the estrous cycle. Furthermore, SMC was expressed in the cervix and vagina of the ovariectomized rat, even though it is not found in the uterine luminal epithelium. Both soluble and membrane-bound forms of SMC were present in these tissues. Immunohistochemical analyses showed distinctive localization patterns of SMC in the various tissues during the estrous cycle. Moreover, the previously unreported expression of SMC/Muc4 in the isthmus, ampulla, and infundibulum of the oviduct suggests potential functions in gamete development. These results indicate that SMC/Muc4 is expressed in most tissues of the female reproductive tract, in which it may have multiple functions. However, hormonal regulation appears to be restricted to the uterine luminal epithelium.

Correlation of asbestos fiber burdens in fallopian tubes and ovarian tissue

Evidence suggests an increased risk of ovarian cancer with asbestos exposure. Ovaries and corresponding fallopian tubes were studied by analytic electron microscopy. There was 71.4% agreement between tube and ovary for presence-type of asbestos. The fallopian tube can provide useful information regarding asbestos exposure when no ovarian tissue is available.

Positive staining for p53 and expression of c-erbB-2 in endosalpinx hyperplasia: analysis of 48 cases and review of literature

To establish the diagnostic value of p53 and c-erbB-2 expression, forty-eight cases of endosalpinx hyperplasia were analyzed. p53 protein and c-erbB-2 oncoprotein expression was examined using an avidin-biotin peroxidase complex method. The accumulation of p53 protein and c-erbB-2 oncoprotein was used as objective evidence to support morphologic differential diagnosis of endosalpinx hyperplasia and early cancer. In all cases various forms of endosalpinx hyperplasia were seen. Only in 4 cases staining for p53 showed positive reaction without staining for c-erbB-2. In one case positive reaction for c-erbB-2 was showed and no expression of p53 protein was detected. It is concluded that immunohistochemical detection of the mutant p53 protein and c-erbB-2 oncoprotein might be useful tools in differential diagnosis among various forms of hyperplastic changes of endosalpinx. The presence of these markers may be associated with the risk of malignant transformation in various forms of the tubal hyperplasia.

Characterization and localization of beta2-adrenergic receptors in the bovine oviduct: indication for progesterone-mediated expression

Beta2-adrenergic receptors were detected in bovine oviductal epithelium by use of receptor binding studies and expression analysis. Complementary DNA cloning gave use to the first full-length bovine beta2-adrenoceptor messenger RNA sequence (2030 bases). Receptor bioactivity in oviduct epithelial cells was characterized by specific ligand interaction and consequent cAMP generation. Expression studies demonstrated an estrous cycle-dependent regulation, with higher transcript levels and significantly increased binding capacity during the luteal phase. After progesterone supplementation, oviduct epithelial cells showed elevated receptor expression in culture, supporting the hypothesis that progesterone up-regulates the beta2-adrenergic receptor within these cells. It seems likely that catecholamines from the circulation or from innervation might be able to influence reproductive success by regulating oviductal secretion.

Characterization and expression of the laminin gamma3 chain: a novel, non-basement membrane-associated, laminin chain

Laminins are heterotrimeric molecules composed of an alpha, a beta, and a gamma chain; they have broad functional roles in development and in stabilizing epithelial structures. Here, we identified a novel laminin, composed of known alpha and beta chains but containing a novel gamma chain, gamma3. We have cloned gene encoding this chain, LAMC3, which maps to chromosome 9 at q31-34. Protein and cDNA analyses demonstrate that gamma3 contains all the expected domains of a gamma chain, including two consensus glycosylation sites and a putative nidogen-binding site. This suggests that gamma3-containing laminins are likely to exist in a stable matrix. Studies of the tissue distribution of gamma3 chain show that it is broadly expressed in: skin, heart, lung, and the reproductive tracts. In skin, gamma3 protein is seen within the basement membrane of the dermal-epidermal junction at points of nerve penetration. The gamma3 chain is also a prominent element of the apical surface of ciliated epithelial cells of: lung, oviduct, epididymis, ductus deferens, and seminiferous tubules. The distribution of gamma3-containing laminins on the apical surfaces of a variety of epithelial tissues is novel and suggests that they are not found within ultrastructurally defined basement membranes. It seems likely that these apical laminins are important in the morphogenesis and structural stability of the ciliated processes of these cells.

Estimates of mouse oviductal fluid tonicity based on osmotic responses of embryos

Zygotes and early cleavage-stage embryos are very sensitive to increased osmolality in vitro, although the tonicity of their in vivo environment, oviductal fluid, is unknown. A preference for low osmolality in vitro might imply similar conditions in vivo or be specific to culture. Previous electron probe x-ray microanalysis measurements of total ion content predicted oviductal fluid osmolalities of 310-360 mOs/kg, higher than osmolalities tolerated by mouse zygotes in vitro. However, such indirect estimates may not reflect the tonicity experienced by embryos. We have now used embryos themselves as osmosensors to determine the tonicity of mouse oviductal fluid. In one method, we measured the mean volume of zygotes in undiluted oviductal fluid and compared this to the mean volumes measured for zygotes in media spanning a range of osmolalities. The osmolality corresponding to the measured mean volume in oviductal fluid was taken to be isotonic. In another, independent method, the sizes of zygotes and two-cell embryos were measured as a function of time beginning immediately after removal from oviducts. The osmolality in which the embryos neither swelled nor shrank was taken to be isotonic. Both methods yielded approximately the same range for the tonicity of oviductal fluid: around 290-300 mOs/kg.