The Effects of Immune Globulins on the Fertilizing Capacity of Frog Spermatozoa1

Abstract

Spermatozoa of Rana pipiens were exposed to nonimmune and to immune globulins directed against egg jellies, secretions from whole or thirds of mature oviducts, heart, ovary, testis and spermatozoa of R. pipiens. Aliquots of treated sperm were washed free of unbound antibodies by centrifugation and used to inseminate normal eggs of R. pipiens; unwashed suspensions of spermatozoa served as additional controls. Treatment with immune globulins against egg jellies and oviducal secretions followed by washing did not significantly affect the fertilizing capacity of the spermatozoa. Treatment with the immune globulins directed against the frog tissues when followed by washing significantly lowered the fertilizing capacity of the spermatozoa. Prior treatment of eggs with immune globulins reduced the fertilization rate, after insemination with normal spermatozoa. The results are interpreted to mean that complementary sites on spermatozoa are blocked by the tissue-directed immune globulins, but not by those prepared against egg jellies or oviducal secretions. Essential initiatory processes of the spermatozoa such as motility or release of sperm lysins may be affected by the treatment with globulins; the inhibition of fertilization by prior treatment of eggs with immune globulins is interpreted as being due to the formation of a precipitation lattice which may block the progress of spermatozoa toward the egg surface.