Regulation of T cell receptor gamma gene expression by cytokines in murine hematopoietic cells.

Murine IL-3-dependent myeloid cell lines express transcripts from non-rearranged TCR gamma genes and this expression is dependent upon IL-3. To investigate this observation in general terms we examined various IL-3 dependent cell lines for TCR gamma gene expression. We also examined various cytokines to test their potential to induce TCR gamma gene expression. All IL-3 dependent cell lines expressed TCR gamma transcripts. The IL-3 induced expression was sensitive to protein synthesis inhibitors. This demonstrated that the TCR gamma genes belong to the early growth factor response class. IL-3, IL-4, GM-CSF and Erytropoietin (EPO), but not G-CSF, induced TCR gene expression. 32D cells transfected with the IL-2 beta chain receptor became responsive to IL-2 as a growth factor and induced TCR gamma gene expression. The induction of TCR gamma gene expression by the cytokines was not correlated to their growth promoting activity. This indicated different signaling pathways.