The mature form of interleukin-1α is constitutively expressed in immature male germ cells from rat

Abstract

In the present study we show that immature germ cells from rat testis contain both interleukin-1α (IL-1α) mRNA and immunoreactive proteins. In contrast, in primary cultures of Sertoli cells and peritubular cells, IL-1α mRNA and immunoreactive protein were below the levels of detection. Immunoblots of lysates from these germ cells showed the presence of strong 17 kDa bands (mature forms of IL-1α) and a much weaker 33 kDa band (precursor form). The finding of cell-associated mature forms of IL-1α in germ cells indicates that immature male germ cells are able to process IL-1α independent of its secretion. Data from isolated cell fractions, as well as from whole testis tissue from rats of various ages, indicate that IL-1α expression takes place in late pachytene spermatocytes and early round spermatids. Whether IL-1α plays a role intracellularly in germ cells or exerts its effects on neighbouring Sertoli cells remains to be shown.