Decreased expression of the heat shock protein hsp70-2 is associated with the pathogenesis of male infertility

Objective: To examine the expression of the heat shock protein hsp70-2, and the possible relationship with the pathogenesis of male infertility. Design: Prospective study. Setting: Reproductive testing laboratory in a university hospital. Patient(s): Men undergoing testicular biopsy during an investigation of sub fertility. Intervention(s): Testicular tissues were obtained from biopsies of men unde rgoing infertility evaluation and subdivided into three groups: normal test es, maturational arrest and Sertoli cell-only syndrome. Immunostaining and Western blotting techniques determined expression of the heat shock protein hsp70-2 Main Outcome Measure(s): Expression of the heat shock protein hsp70-2 in th e testes. Result(s): The experimental data demonstrated that the heat shock protein h sp70-2 was expressed in the normal and maturation arrest testicular specime ns. The heat shock protein hsp70-2 was strongly present in the cytoplasm of spermatocytes and spermatides in the adluminal compartment of the seminife rous epithelium in normal testis. However, maturation arrest testis tissue demonstrated light staining in spermatocytes and spermatides, and Sertoli-o nly specimens demonstrated no staining for the heat shock protein hsp70-2. The Western blotting data showed a 70-kDa heat shock protein in the normal and maturation arrest testicular tissues, but not in the Sertoli-only tissu es. Conclusions: These results suggest that the heat shock protein hsp70-2 is e xpressed in spermatocytes and spermatides in normal and maturation arrest t issues. However, the expression of the heat shock protein hsp70-2 was low i n maturation arrest, and no heat shock protein hsp70-2 was demonstrated in Sertoli-only specimens. Therefore the decreased expression of the heat shoc k protein hsp70-2 is associated with the pathogenesis of male infertility. (Fertil Steril (R) 2001;76:1136-9. (C) 2001 by American Society for Reprodu ctive Medicine.).