Both D factor/LIF and IL-6 inhibit the differentation of mouse teratocarcinoma F9 cells

Differentation-stimulating factor (D factor)/leukemia inhibitory factor (LIF) and IL-6 are reported to be cytokines having multifaced functions including the induction of differentation in mouse myeloid leukemia MI cells. We here report that both D factor/LIF and IL-6 inhibit the differentation of mouse teratocarcinoma F9 cells induced by retinoic acid alone or combined with dibutyryl cAMP. From the microscopic observation as well as Northern blot analysis using cDNA probes encoding several marker proteins for differentiation of F9 cells, we conclude that D factor/ LIF and IL-6 are functionaly closely related in the induction of differentation in MI cells in the inhibition of F9 differentiation.