Effects of antisera on human sperm penetration of zona-free hamster ova

Human sperm, after treatment with a 10% concentration of rabbit or rhesus monkey normal sera and antisera, were evaluated for fertilizing potential by incidence of zona-free hamster ova penetrated by the sperm as evidenced by the presence of swollen sperm heads and male pronuclei. Compared with the basic medium alone, treating sperm with normal sera tended to increase the percentage of ova penetrated whereas antisera against sperm, sperm extract, and testis caused significant decreases in ova penetrated. A Fab preparation of these antisera exhibited similar inhibitory effects. Antisera Fab treatment of the zona-free ova prior to exposure to sperm had no effect on penetration rate.