ABSTRACT
<p><b>AIM</b>To understand the biological functions of the ectoplasmic specializations between Sertoli cells and maturing spermatids in seminiferous epithelia.</p><p><b>METHODS</b>In order to disrupt the function of the ectoplasmic specializations, nectin-2, which is expressed at the specialization, was neutralized with anti-nectin-2 antibody micro-injected into the lumen of the mouse seminiferous tubule. Anti-nectin-3 antibody was also micro-injected into the lumen in order to neutralize nectin-3, which is expressed at the specialization.</p><p><b>RESULTS</b>The actin filaments at the specialization disappeared, and exfoliation of maturing spermatids was observed by electron microscopy.</p><p><b>CONCLUSION</b>Nectin-2 was neutralized by anti-nectin-2 antibody and nectin-3 was neutralized by anti-nectin-3 antibody, respectively. Inactivated nectin-2 and nectin-3 disrupted the nectin-afadin-actin system, and finally the actin filaments disappeared. As a result, the specialization lost the holding function and detachment of spermatids was observed. One of the functions of the specialization seems to be to hold maturing spermatids until spermiation.</p>
Subject(s)
Animals , Male , Mice , Actins , Metabolism , Antibodies , Allergy and Immunology , Pharmacology , Cell Adhesion Molecules , Allergy and Immunology , Metabolism , Cell Communication , Physiology , Intercellular Junctions , Metabolism , Mice, Inbred ICR , Microfilament Proteins , Metabolism , Microscopy, Confocal , Nectins , Seminiferous Epithelium , Cell Biology , Metabolism , Sertoli Cells , Cell Biology , Metabolism , Spermatids , Cell Biology , MetabolismABSTRACT
<p><b>AIM</b>To isolate and transplant germ cells from adult mouse testes for transplantation.</p><p><b>METHODS</b>In order to distinguish transplanted cells from endogenous cells of recipients, donor transgenic mice expressing green fluorescent protein (GFP) were used. Germ cells were collected from the donors at 10-12 weeks of age and spermatogonia were concentrated by percoll fractionation and transplanted into recipient seminiferous tubules that had been previously treated with busulfan at 5 weeks of age to remove the endogenous spermatogenic cells.</p><p><b>RESULTS</b>Twenty weeks after the transplantation, a wide spread GFP signal was observed in the recipient seminiferous tubules. The presence of spermatogenesis and spermatozoa was confirmed in sections of 12 out of 14 testes transplanted (86 %). However, when germ cells were transplanted without concentration the success rate was zero (0/9).</p><p><b>CONCLUSION</b>Germ cells from adult mouse testes can be successfully transplanted into recipient seminiferous tubules if the cell population is rich in spermatogonia and the percoll fractionation is useful in obtaining such a cell population.</p>