Production of IL-2 and IFN by TH2 clones.

We have studied the production of IL-2, IL-4 and IFN-gamma by a panel of CD4+ clones produced in our laboratory. The clones were classified as TH1 and TH2 because of their ability to secrete IL-2 or IL-4, respectively, following stimulation with APC + Ag and by their characteristic proliferative responses to exogenous IL-2 or IL-4. Some of the TH2 clones, all of which happened to be autoreactive, produced IL-2 and one of these, as well as one antigen-reactive TH2 clone, also secreted IFN-gamma following stimulation with immobilized anti-CD3 mAb. IL-2 production by TH2 cells required higher concentrations of anti-CD3 mAb than IL-4 production. Thus, the TH2 clones seem to be heterogeneous. We designate the IL-2/IL-4 secretors as TH2B and those making IL-4 as TH2A clones.