[Immune-testicular regulation and cytokines]

The pathogenesis of male infertility can be reflected in alterations of spermatogenesis caused by testicular cancer, aplasia of the germinal cells, varicocele, environmental factors or defect in the transport of the sperms, among others. In general, 48% of men suffer unexplained infertility. During a long time, the masculine reproductive tract and the immune system have been studied as different and independent systems. However, in the last two decades a particular interest has arisen in the interaction of both systems on masculine infertility, in particular in the evaluation of antisperm antibodies as a common cause of infertility. Also, the inflammation due to genital or systemic infections can cause alterations in the testicular function. The recognition of intratesticular antigens provokes the production of antibodies by B lymphocytes. Then, the immune system induces a cellular response, by cytokines secretion, activation of complement and T lymphocytes activation. In this review the components and the immune system response mechanism, the organization of the testicle as a reproductive organ and the mediators of the immunologic response will be examined: interleukin-1 (IL-1), IL-6, leukaemia Inhibitory factor, tumor necrosis factor-alpha, the molecule FasL (CD95L) and Fas (CD95), macrophage migration-inhibitory factor, mononuclear phagocyte colony stimulating factor, Granulocyte/macrophage colony stimulating factor, as well as stem cell factor, interferon, transforming growth factor B and activins.