title: Immunohistochemical study of seminiferous epithelium in adult bovine testis using monoclonal antibodies against Ki-67 protein and proliferating cell nuclear antigen (PCNA).
abstract: The distribution pattern of proliferating cell nuclear antigen (PCNA) and Ki-67 protein was studied in adult bovine seminiferous epithelium by means of immunohistochemistry using monoclonal antibodies. Tailoring the methodological protocol for each of the two proliferation markers was a necessary prerequisite for obtaining optimal results in tubular sections and whole-mounts. A-, I- and B-spermatogonia displayed PCNA-positive nuclei, except during meta-, ana- and telophases of mitosis. PCNA-negative nuclei in the basal tubular compartment, excluding those from non-cycling Sertoli cells, belonged to the spermatogonia precursor cell line. However, only about 30%, 45% and 47% of the respective A-, I-, B-spermatogonia had positive nuclei after exposure to the MIB-1 antibody directed against the Ki-67 protein. Spermatogonia with MIB-1-negative nuclei represented cells in the G1-phase. Both antibodies reacted intensely with the nuclei of preleptotene primary spermatocytes. PCNA reactivity was also present during leptotene through pachytene. Ki-67 protein expression was absent during leptotene and zygotene but was again encountered during pachytene and meiosis I and II. Anti-PCNA/anti-protein gene product 9.5 double-labelling indicated that the transition from spermatogonia precursor cells into A1-spermatogonia is not strictly synchronized in a given tubular segment, a possible reason for the flexibility in A-spermatogonial propagation seen in bovine seminiferous tubules.
authors.affiliation: Institut für Anatomie der Universität, Universitätsstrasse 31, D-93040 Regensburg, Germany.
authors.forename: K H
authors.initials: KH
authors.lastname: Wrobel
authors.forename: D
authors.initials: D
authors.lastname: Bickel
authors.forename: R
authors.initials: R
authors.lastname: Kujat
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D015415:Biomarkers; D002417:Cattle; D002453:Cell Cycle; D002455:Cell Division; D004847:Epithelial Cells; D004848:Epithelium / Q000737:chemistry; D019394:Ki-67 Antigen; D008297:Male; D008540:Meiosis; D009363:Neoplasm Proteins / Q000032:analysis* / Q000276:immunology; D009687:Nuclear Proteins / Q000032:analysis* / Q000276:immunology; D018809:Proliferating Cell Nuclear Antigen / Q000032:analysis* / Q000276:immunology; D012671:Seminiferous Tubules / Q000737:chemistry / Q000166:cytology*; D013091:Spermatogenesis; D013093:Spermatogonia / Q000737:chemistry
chemical_list: D000911:Antibodies, Monoclonal; D015415:Biomarkers; D019394:Ki-67 Antigen; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; D018809:Proliferating Cell Nuclear Antigen