SPECIFIC EXPRESSION OF HUMAN C-FGR IN NATURAL IMMUNITY EFFECTOR-CELLS

The c-fgr gene product was shown by immune complex protein kinase assay with specific antibodies to be a 58-kilodalton protein (p58(c-fgr)) with tyrosine-specific autophosphorylating activity. On examination of peripheral blood cells by immunoblotting with anti-c-fgr antibodies, p58(c-fgr) was found only in the fractions of monocytes, granulocytes, and natural killer cells. On the other hand, histochemical studies of hybridization demonstrated accumulation of c-fgr transcripts on most monocytes and large lymphocytes. In hematopoietic cell lines, p58(c-fgr) was detected in differentiated granulocytic cells as well as in differentiated monocytic cells of HL-60-cell origin. These data suggest a specific role for p58(c-fgr) in natural immunity effector cells.