RECONSTITUTION OF THE RESPONSE TO LEUKEMIA INHIBITORY FACTOR, ONCOSTATIN-M, AND CILIARY NEUROTROPHIC FACTOR IN HEPATOMA-CELLS

Ciliary neurotrophic factor (CNTF) has been described as a neuro-activ e cytokine that shares functional similarities with the leukemia inhib itory factor (LIF). We demonstrate here that, like LIF, CNTF stimulate s expression of acute phase plasma proteins in rat H-35 hepatoma cells . Transfection of the LIF receptor into Hep3B hepatoma cells reconstit uted LIF and oncostatin M regulation of acute phase plasma protein gen es. Co-expression of the LIF receptor and the CNTF receptor, but not e xpression of either subunit alone, generated CNTF responsiveness in He p3B cells, suggesting cooperativity of these receptor subunits. Eviden ce is presented for direct interaction of the LIF receptor with the in tracellular signal transduction machinery.