Fig. 3. Western blot analysis of MT1-MMP in purified testicular cells. Cell lysates of 5-day-old cultured peritubular (C.Pc) and Sertoli (C.Sc) cells, and of freshly isolated Sertoli cells (FI.Sc), spermatocytes (FI.SPC), spermatids (FI.SPT), or mixed germ cells (FI.CGc) were prepared. 40 µg of proteins were loaded on to 7.5% SDS-PAGE gels. (+) and (-) indicate whether or not trypsin has been used in the course of the germ cell isolation.