In addition, PB and SF T cells from RA patients,when stimulated with IL-21 and anti-CD3 monoclonal antibody, secreted markedly higherlevels of TNF-α and IFN-γ than those from controls, indicating that IL-21 enhances localT-cell activation and pro-inflammatory cytokine secretion (75). The gene discussed is IL21; the disease is rheumatoid arthritis.