IL2 and arthritic joint disease: We hypothesized that chronic CHIKV arthritis activity was associated with deficient IL2-mediated Treg levels; therefore, we tested the therapeutic effects of recombinant IL2 (rIL2), an anti-IL2 JES6-1 monoclonal antibody (mAb), and an rIL2/anti-IL2 JES6-1 mAb complex on post-CHIKV arthritis in our mouse model.