MALE GENITAL TRACT IMMUNITY WITKIN ET AL. / Anti-inflammatory ,...._,...___ .y,u,= No immune activation Fig. I. Regulation of immune responses in the male genital tract. In the absence of infection spermatozoa do not activate pro-inflammatory immune responses from macrophages (M) or CD4/ a13 T cells (Ta[3). When the male genital tract is infected pro-inflammatory cytokines are induced and B lymphocytes (B) produce antibodies. /8 T cells (T/8) are in the magnitude of these responses due to genetic variability, or some combination of both. ACKNOWLEDGMENT We thank Dr. Andreas Neuer for critical discussions REFERENCES 1. Witkin SS: Mechanisms of active suppression of the immune response to spermatozoa. Am J Reprod Immu- nol Microbiol 17:61-64, 1988. 2. Mahi-Brown CA, Yule TD, Tung KSK: Evidence for active immunological regulation in prevention of testicu- lar autoimmune disease independent of the blood-testis 134 INFECTIOUS DISEASES IN OBSTETRICS AND GYNECOLOGY P’ro-im,ammaory Cytokines Induction : X’ Antibodies to Sperm & Microbes stimulated by activated B cells and inhibit further antibody production. Pro-inflammatory cytokines and / T cells initi- ate heat shock protein (HSP) gene transcription which down-regulates further pro-inflammatory cytokine biosyn- thesis. barrier. Am J Reprod Immunol Microbiol 16:165-170, 1988. 3. Dym M, Fawcett DW: The blood-testis barrier in the rat and the physiological compartmentation of the semi- niferous epithelium. Biol Reprod 3:308-326, 1970. 4. Tung KSK, Yule TD, Mahi-Brown CA, Listrom MB: Distribution of histopathology and Ia positive cells in actively induced and passively transferred experimental autoimmune orchitis. J Immunol 138:752-759, 1987. 5. Belier DI: Functional significance of the regulation of macrophage Ia expression. Eur J Immunol 14:138-143, 1984. 6. EI-Demiry M, James K: Lymphocyte subsets and macro- phages in the male genital tract in health and disease. Eur Urol 14:226-235, 1988.