Cytokines and the immune-testicular axis.
Cytokines are regulatory proteins involved in haematopoiesis, immune cell development, inflammation and immune responses. Several cytokines have direct effects on testicular cell functions, and a number of these are produced within the testis even in the absence of inflammation or immune activation events. There is compelling evidence that cytokines, in fact, play an important regulatory role in the development and normal function of the testis. Pro-inflammatory cytokines including interleukin-1 and interleukin-6 have direct effects on spermatogenic cell differentiation and testicular steroidogenesis. Stem cell factor and leukaemia inhibitory factor, cytokines normally involved in haematopoiesis, also play a role in spermatogenesis. Anti-inflammatory cytokines of the transforming growth factor-beta family are implicated in testicular development. Consequently, local or systemic up-regulation of cytokine expression during injury, illness or infection may contribute to the disruption of testicular function and fertility that frequently accompanies these conditions. The aim of this review is to provide a very brief summary of the extensive literature dealing with cytokines in testicular biology, and to follow this with some speculation concerning the significance of these molecules in interactions between the immune system and the testis.
Hedger
Mark P
MP
Monash Institute of Reproduction and Development, Monash University, 27-31 Wright Street, Clayton, Melbourne, Victoria 3168, Australia. mark.hedger@med.monash.edu.au
Meinhardt
Andreas
A
D000818:Animals; D003115:Colony-Stimulating Factors / Q000276:immunology; D016207:Cytokines / Q000276:immunology*; D053222:Fas Ligand Protein; D006131:Growth Inhibitors / Q000276:immunology; D006801:Humans; D007249:Inflammation / Q000276:immunology; D007372:Interferons / Q000276:immunology; D007375:Interleukin-1 / Q000276:immunology; D015850:Interleukin-6 / Q000276:immunology; D053605:Leukemia Inhibitory Factor; D008222:Lymphokines / Q000276:immunology; D008263:Macrophage Migration-Inhibitory Factors / Q000276:immunology; D008297:Male; D008562:Membrane Glycoproteins / Q000276:immunology; D013091:Spermatogenesis / Q000276:immunology; D019089:Stem Cell Factor / Q000276:immunology; D013737:Testis / Q000276:immunology*; D016212:Transforming Growth Factor beta / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology
D003115:Colony-Stimulating Factors; D016207:Cytokines; C505661:FASLG protein, human; D053222:Fas Ligand Protein; D006131:Growth Inhibitors; D007375:Interleukin-1; D015850:Interleukin-6; C507837:LIF protein, human; D053605:Leukemia Inhibitory Factor; D008222:Lymphokines; D008263:Macrophage Migration-Inhibitory Factors; D008562:Membrane Glycoproteins; D019089:Stem Cell Factor; D016212:Transforming Growth Factor beta; D014409:Tumor Necrosis Factor-alpha; D007372:Interferons