In vitro studies in reproductive immunology : 1. Suppression of cell-mediated immune response by human spermatozoa and fractions isolated from human seminal plasma

Abstract

Components of the male mammalian genital tract are capable of inhibiting in vitro cell-mediated immune responses. In the current study, intact human spermatozoa in a concentration of 10 7 cells/ml inhibited both spontaneous and PHA-M- and Con A-induced blast transformation of normal human peripheral blood lymphocytes. Similar inhibitory properties were found in human seminal plasma using concentrations of 100 and 400 μg/ml. Sephadex G-100 chromatography of seminal plasma yielded five fractions (F 1 - F 5) which were qualitatively assessed by SDS-polyacrylamide disc gel electrophoresis. Fractions 1 and 4 inhibited spontaneous blast transformation while fractions 1 and 3 inhibited mitogen-induced blastogenesis. Normal leukocyte migration was not affected by fractions. It is concluded that suppression of blast transformation might be due to a spermatozoal or seminal plasma component(s) able to bind receptors on lymphocytes specific for PHA-M and Con-A.