THE MATURE FORM OF INTERLEUKIN-1-ALPHA IS CONSTITUTIVELY EXPRESSED INIMMATURE MALE GERM-CELLS FROM RAT

In the present study we show that immature germ cells from rat testis contain both interleukin-1 alpha (IL-1 alpha) mRNA and immunoreactive proteins. In contrast, in primary cultures of Sertoli cells and peritu bular cells, IL-1 alpha mRNA and immunoreactive protein were below the levels of detection. Immunoblots of lysates from these germ cells sho wed the presence of strong 17 kDa bands (mature forms of IL-1 alpha) a nd a much weaker 33 kDa band (precursor form). The finding of cell-ass ociated mature forms of IL-1 alpha in germ cells indicates that immatu re male germ cells are able to process IL-1 alpha independent of its s ecretion. Data from isolated cell fractions, as well as from whole tes tis tissue from rats of various ages, indicate that IL-1 alpha express ion takes place in late pachytene spermatocytes and early round sperma tids. Whether IL-1 alpha plays a role intracellularly in germ cells or exerts its effects on neighbouring Sertoli cells remains to be shown.