antigen-activated t lymphocytes produce within 24 h of stimulation a factor that is indistinguishable biochemically and functionally from the b cell co-stimulating growth factor , bcgf-i , originally identified in induced el4 supernatants : supernatants from antigen-stimulated t cell lines are not directly mitogenic for resting b cells , but synergize in an h-2-unrestricted manner with anti-ig activated b cells to produce polyclonal proliferation but not antibody-forming-cell development ;
C0021027
ig
C0003241
antibody