Interactions between prostasomes and leukocytes

Prostasomes are membranous vesicles (150-200 nm diameter) present in human semen. They are secreted by the prostate gland and contain large amounts of cholesterol, sphingomyelin and Ca2+. In addition, some of their proteins are enzymes. Prostasomes enhance the motilily of ejaculated sperm and are involved in a number of biological functions. In a previous work, we found that prostasome can fuse to spermatozoa at slightly acidic pH values, as demonstrated by the transfer of the lipophilic octadecylrhodamine probe. In this paper, Rie study the interactions of two leukocyte populations (polymorphonuclear and mononuclear) with prostasomes and find a pi-I-dependent adhesion (revealed by microscopic observation), but no fusion. These phenomena may be relevant for the functions of leukocytes in human reproduction. (C) 1998 Elsevier Science B.V. All rights reserved.