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The oligosaccharide moiety of human, porcine and bovine zonae pellucidae was studied with lectins and monoclonal antibodies specific for tri- or tetra-saccharidic epitopes containing at least one terminal alpha-L-fucose. Animal eggs were collected from follicular aspirates, human eggs were collected from in-vitro fertilization and embryo transfer programmes and pooled into six groups. By direct immunofluorescence, the lectins reactivity was detected for the animal or the human zonae pools in the same way. Reactivity of Aleuria aurantia lectin demonstrated the presence of alpha-L-fucose terminal residues in the zonae from the three species studied. By indirect immunofluorescence, the 2-25 antibody reactivity was detected in every pool of human zonae whereas there was no evidence of any antibody reactivity on animal zonae. Using an anti-Lewis-b blood group antibody (2-25), we observed expression of this antigen as an intrinsic component of the human zona pellucida, independently of patients' Lewis red blood cell phenotypes. Antibody 2-25 inhibited the spermatozoa-zona binding in a hemizona assay, suggesting that this fucose-containing antigen could be part of a sperm-zona receptor.

Objective: To evaluate the utility of zona drilling for human severe sperm alterations in in vitro fertilization (IVF)., Design: A prospective randomized study was conducted according to random assignment of collected oocytes to a control or zona drilling procedure., Setting: Reproductive Biology Laboratory, University Hospital of Nantes, France., Patients: Twenty infertile couples with severe semen defects and previous IVF failure., Interventions: Ultrasound-guided transvaginal follicular aspiration., Results: Fertilization rates were compared to assess the advantages of zona drilling: 93% (80/86) drilled oocytes survived and 18.75% (15) were fertilized, whereas only 3% (3/100) control oocytes were fertilized. The polyspermy rate for fertilized drilled oocytes was high (10/15; 66.6%). The normal fertilization rate after zona drilling remained very low (5/86; 5.8%) and was not statistically different from that of control oocytes (3/100; 3%). One implantation occurred after replacement of five drilled embryos in three patients but resulted in early miscarriage. Replacement of the single control embryo led to a progressive pregnancy and normal male birth., Conclusions: This study indicates that zona drilling does not improve IVF results in cases of severe semen alterations.

Ultrathin sections are stained immediately after cutting by placing them in contact with staining solution and then placed on a slide covered by a celloidin film. This method largely avoids precipitates of heavy metals. The recovering of celloidin film is improved using a stainless steel basket. This technique is far more reliable than that involving use of a filter paper.

We have developed hybridomas producing anti-islet cell monoclonal autoantibodies (IC-MC auto Ab), by fusion of splenocytes from C57BLKsJ db/db diabetic mice with the SP2/O-Ag 14 myeloma. These IC-MC auto Ab were screened by an enzyme-linked immunosorbent assay, for their binding-ability to RINm5F insulinoma cells. Twenty IC-MC auto Ab were produced, which have differing immunoglobulin isotypes. Four of them induced a complement-dependent lysis of RINm5F cells in vitro, while the others did not. These two populations of auto Ab reflect the duality found in the intact db/db mouse. Immunoperoxidase procedures demonstrated that IC-MC auto Ab bound specifically to beta cell antigens of control pancreatic sections, in a similar pattern as auto Ab spontaneously "trapped" in the islets of db/db mice. Electron microscopic studies with an immunogold staining suggested that target antigens for IC-MC auto Ab were predominantly located in the cytoplasmic matrix of beta cells and, to a lesser extent, on their membranes. These antibodies represent powerful reactives for the studies concerning with the pathogeny of diabetes.

A high-resolution autoradiographic study was conducted on 268 thin sections of endocrine cells in the rabbit colon following injection of (3H) L-dopa. Using quantitative autoradiography, silver-proteinate impregnation, granulometry, and statistical analysis of cell populations by the Falck procedure, three cell types were identified--EC, L; and H--as well as a single cell with distinct ultrastructural characteristics. For the first time, a fine quantitative estimation of the handling ability of amine precursor related to the cross-sectional areas of each cell type was obtained, using a Kontron Digiplan image analyzer. All cells studied showed the ability to take up the precursor. Labeling indices were 6.63, 2.15, and 2.14 for EC, L, and H, respectively. These data and silver-proteinate impregnations provide good criteria for differentiating EC from H cells despite morphological similarities. After critical analysis of granule diameters, L cells were considered to be pluripotential in secretory activity.

A 27 +/- 1 days old human embryo arising from an ectopic pregnancy was incubated with 3,4, L-dihydroxyphenylalanine (L-DOPA) to investigate whether cells of the gut primordium have at this early stage of development, the ability to take up the amine precursors. We could observe that a few cells exhibiting greenish fluorescence were located in the epithelium wall of the fore gut. Most of them were situated in contact with the basal lamina and possessed a long apical process extending over towards the gut lumen. The uptake of amine precursor, the morphology and the location of these cells strongly suggest that they represent the gut endocrine precursor cells of the human embryo.