Expression of alpha and gamma interferon receptors in the sperm cell

The present study was conducted to examine whether or not the sperm cell has the expression of receptors for interferon (IFN) ‐α and ‐γ. This was investigated using specific antibodies. Antibody to IFN‐α receptor reacted with the acrosomal and tail regions of the murine sperm cell in the indirect immunofluorescence technique (IFT) and immunoscanning electron microscopic procedure (ISEP). In the immunoprecipitation and Western blot procedures, this antibody specifically recognized a protein band of ≈100 kD, which corresponds to the molecular weight of IFN‐α receptor present in other cell types. Antibody to IFN‐γ receptor specifically reacted with the posterior head, midpiece, and tail regions of sperm cell in IFT and ISEP, and recognized a band of ≈85 kD in the immunoprecipitation and Western blot procedures, corresponding to the IFN‐α receptor. Similar bands of ≈100 kD and ≈85 kD molecular identities were also detected in the testes extracts and sperm extracts of other mammalian species namely human, rabbit, and pig, the species tested. These findings indicate that the mammalian sperm cell has expression of IFN‐α and IFN‐γ receptors, which seem to develop during spermatogenesis in the testes. These findings may have implications in male infertility and antisperm contraceptive vaccine development. Mol. Reprod. Dev. 56:189–197, 2000. © 2000 Wiley‐Liss, Inc.