Immunoregulatory activity in adult rat testicular interstitial fluid: roles of interleukin-1 and transforming growth factor beta.
Studies on the effect of rat testicular interstitial fluid (IF) on T-cell function have reported both stimulatory and inhibitory actions. Specific cytokines produced within the testis, particularly interleukin-1 (IL-1) and transforming growth factor beta (TGFbeta), may contribute to these apparently conflicting observations. In proliferation assays employing lectin- or antibody-activated thymocytes or mature T cells in vitro, adult rat testicular IF stimulated T-cell activation and/or proliferation at low assay doses and was inhibitory at higher doses. The stimulatory activity was blocked by recombinant IL-1 receptor antagonist. The inhibitory activity was not affected by a polyspecific TGFbeta antiserum. The biological characteristics of the inhibitor were distinct from those of a similar, but considerably less potent, activity in platelet-depleted serum. These data demonstrate that rat testicular IF contains biologically significant concentrations of IL-1 but has a predominantly inhibitory action on T-cell responses. The factor predominantly responsible for this inhibitory activity displays a relatively large apparent molecular weight, is protease sensitive and partially heat labile, but does not appear to be one of the known mammalian TGFbeta isoforms.
Hedger
M P
MP
Institute of Reproduction and Development, Monash University, Monash Medical Centre, Clayton, Victoria, Australia. mark.hedger@med.monash.edu.au
Nikolic-Paterson
D J
DJ
Hutchinson
P
P
Atkins
R C
RC
de Kretser
D M
DM
D000818:Animals; D005110:Extracellular Space / Q000276:immunology*; D006801:Humans; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1 / Q000276:immunology*; D008213:Lymphocyte Activation; D008297:Male; D051379:Mice; D008809:Mice, Inbred C3H; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins / Q000494:pharmacology; D012795:Sialoglycoproteins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000276:immunology; D013737:Testis / Q000276:immunology*; D016212:Transforming Growth Factor beta / Q000276:immunology*
C507763:IL1RN protein, human; C507764:Il1rn protein, mouse; D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1; D011994:Recombinant Proteins; D012795:Sialoglycoproteins; D016212:Transforming Growth Factor beta