human interleukin-4 , a lymphokine that activates b lymphocytes , appears to employ phosphatidylinositol 4,5-bisphosphate hydrolysis as a brief initial signal that is followed by a sustained rise in cyclic adenosine monophosphate ( camp ) : both signals are needed for the successful induction of the surface antigen cd23 .
C0004561
b lymphocytes
C3273109
antigen cd23