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Specific terminal carbohydrate structures and mucin-associated glycans increase in expression within the human endometrial epithelium during the secretory phase of the menstrual cycle but exhibit wide intercellular variation. We postulated that variation in glycosylation between cells would produce differences in the glycocalyx and result in complex mixtures of cells bearing different combinations of glycans. MUC-1 mucin, keratan sulphate and fucosylated lactosaminoglycans were examined in epithelial gland fragment cultures with antibodies (HMFG1, 5D4) and a lectin (Dolichos biflorus agglutinin). The glycocalyx was examined by transmission and high resolution scanning electron microscopy. The data were related to patterns of expression seen in vivo. The MUC-1 mucin was expressed relatively uniformly in culture, but heterogeneity was evident in mucin sialylation within the epithelial cell population. Double labelling of gland explant cultures for combinations of fucosylated lactosaminoglycans, keratan sulphate and MUC-1 demonstrated cells expressing all combinations of these markers. Ultrastructural examination confirmed remarkable intercellular variation in the glycocalyx. Though the human endometrial epithelium is relatively morphologically homogeneous, these observations reveal complex variations of cell surface glycosylation between neighbouring cells and suggest that secretory function might vary in a similar fashion. [ABSTRACT FROM AUTHOR]

MUC1 is a cell-surface and secretory product of endometrial epithelium. Immunohistoehemical studies carried out using two different antibodies to the mucin-type tandem repeat region of MUC1 indicate a cell-surface location in proliferative phase glands, with intracellular deposits accumulating in the early secretory phase. Commencing 3–4 days after the luteinizing hormone (LH) peak and continuing into the late secretory phase, secretory MUC1 appears in gland lumens. Uterine flushings were collected as a function of time after the LH peak and were analysed using a two-site enzyme-linked immunosorbent assay for MUC1. Low but measurable concentrations were observed up to day 7, while on days 7–13 much higher values were obtained. In women suffering from recurrent spontaneous miscarriage, the concentration of MUC1 in flushings wassignificantly lower than in the controls on day LH+10. Lower values were also observed on days 7 and 13. Reduced epithelial secretory function and a resultant change uterine fluid composition are features of endometrium from recurrent miscarriage patients. [ABSTRACT FROM PUBLISHER]

The presence of cell adhesion molecules on human oocytes, early embryos, and pre-hatched blastocysts was examined by indirect immunofluorescence and compared to the distribution found on first trimester villous placenta with the same antibodies. Six integrin subunits (α3, αV, β1, β3, β4, β5) were observed consistently throughout preimplantation development. Evidence was also obtained for the presence of integrin subunits α2, α4, αL, β2, and β7 on a small number of oocytes. A more restricted developmental analysis of E-cadherin, ICAM-1, NCAM, and VCAM-1 demonstrated that these cell adhesion molecules are also present on oocytes and early embryos. L-selectin was detected on oocytes but was not found on 8-cell embryos. The oocyte and early blastomeres have complex surfaces in which the integrin and CAM families are represented. [ABSTRACT FROM PUBLISHER]

The cell surface glycoprotein CD44 has been demonstrated in a variety of cell types in embryonic and adult tissues. We have established that CD44 is present on human oocytes, cumulus cells, early embryos and pre-hatched blastocysts by indirect immunofluorescence. We have also shown that CD44 is present on 8–11 week placental stroma cells, but not on the trophoblast. These findings demonstrate that CD44 is present throughout preimplantation development, and that down-regulation occurs on the embryonic surface after implantation. [ABSTRACT FROM PUBLISHER]

Secretory differentiation of endometrium after multiple follicular stimulation using gonadotrophin releasing hormone and human menopausal gonadotrophin has been studied both histologically and immunohistochemically in 30 women undergoing in-vitro fertilization treatment. None had embryo transfer. Patients were randomly allocated to receive luteal phase support with a single dose of human chorionic gonadotrophin. The latter failed to produce any significant enhancement of endometrial structure or secretions. Appropriate glandular morphology was present in a greater proportion of those who were successfully stimulated than those who responded poorly. However, defective secretion of the cycle-dependent component studied, using monoclonal antibody D9B1, was demonstrated in two-thirds of cases regardless of the ovarian response. Early vascular maturation in the stroma was a common finding, and was thus considered as a feature of structural modulation of these endometria. [ABSTRACT FROM AUTHOR]

This paper reports the pattern of production and secretion of a secretory phase epitope in the endometrium of 44 normal fertile women. Peroxidase immunochemistry was used to detect the monoclonal antibody D9B1, which binds to a peptide-associated sialylated oligosaccharide, in endometrial biopsies all chronologically dated from the luteinizing hormone (LH) peak. During the proliferative phase, the epitope was shown to be absent from tissue sections. It first made its appeareance within gland cells 2 days after the LH peak. By LH+3 a rapid accumulation of the D9B1 epitope was noted in the base of the cell, below the nucleus. On subsequent days, increasing amounts of the antigen were detected in the apical cytoplasm, apparently in a more concentrated form than in the basal cell zone. On day LH+6, around the time of implantation, secretory vesicles in the cell apex were discharged into the gland lumen where the glycoconjugate finally accumulated. This immunohistochemical approach introduces a new parameter for evaluation of endometrial function and could be used to improve the accuracy of histological assessment of the endometrial cycle [ABSTRACT FROM PUBLISHER]

A monoclonal antibody which identifies a component of post-ovulatory endometrial secretions is now shown to be expressed within the cytoplasm and on the cell surface of both microvillous and ciliated epithelial cells. A glandular explantatlon model was developed in order to study the ‘carry over’ of this secretion to the regenerative phase endometriwn. A loss of cytoplasmic antigen was observed . However, it was retained on the cell surface in a fashion consistent with its expression at the time of explantation. Mosaicism of expression of this secretory component occurs throughout the secretory-phase and is particularly pronounced at the time of transition from proliferative to secretory phase. It is conduded that both ciliated and microvillous epithelial cells produce a post-ovulatory secretory component which may be retained on the cell surface in the absence of hormonal stimulation. [ABSTRACT FROM PUBLISHER]

Studies the mechanisms that release insulin-like growth factors (IGF) from IGF binding proteins (IGFBP-1) at the maternal-fetal interface. Characterization of IGFBP-1 isoforms at the maternal-fetal interface; Proteolysis of IGFBP-1 at the maternal-fetal interface; Characterization of the protease present in amniotic fluid and conditioned medium from decidualized endometrial cells.