in addition , these activities are not derived from the growth factors reported previously such as interleukin 2 ( morgan , r. , ruscetti , f. and gallo , r. c. ( 1976 ) science 193 , 1007-1008 ) and transforming growth factor ( de larco , j. e. and todaro , g. j . ( 1978 ) proc . natl . acad . sci . u.s.a. 75 , 4001-4005 ) .
C0018284
growth factors
C0040691
transforming