IL-32 alpha is the shortest and most abundant of four potential splice variants of the proinflammatory cytokine IL-32 (previously called NK4) with a predicted unmodified size of 15 kDa. Potential modifications include myristoylation and N-glycosylation. Transfected IL-32 alpha was more likely to be cell-associated as compared to IL-32 beta, suggesting an intracellular function. IL-32 is induced by mitogens in peripheral lymphocytes, by IFN-gamma in epithelial cells, or by IL-12 with IL-18 in NK cells and in turn induces cytokine expression. No ortholog has been found in mouse.