Prostasome-like granules from the PC-3 prostate cancer cell line increase the motility of washed human spermatozoa and adhere to the sperm

Objective: Prostasome-like granules are present in the PC-3 prostate cancer cells. Since the seminal prostasomes are able to promote the forward motil ity of human spermatozoa. we conducted a study to determine whether PC-3 pr ostasomes exerted effects similar to those of seminal prostasomes on buffer -washed spermatozoa from normospermic semen samples. Study design: We used computer-assisted sperm analysis (CASA) and immunostaining of prostasomes t o find out where these granules are located on the spermatozoa. Results: Ad dition of PC-3 prostasomes increased the proportion of motile spermatozoa f rom 12-15% to 50-70% (p <0.001). The optimal protein concentration of these prostasomes was 0.1 mg/ml. Heat treatment of PC-3 prostasomes did not decr ease their motility-promoting effect. Immunostaining with anti-prostasome m onoclonal antibody (mAb78) revealed that the PC-3 prostasomes and seminal p rostasomes adhered to the sperm cells. The staining, which occurred all ove r the spermatozoa. was intense on the mid-pieces and weaker on the sperm he ads. Herewith, some prostasome component may activate the spermatic mitocho ndrial function, thus increasing sperm motility. Conclusion: it is conclude d that PC-3 prostasomes bear a functional resemblance to seminal prostasome s as regards sperm motility promotion. <(c)> 2001 Elsevier Science Ireland Ltd. All rights reserved.