Several other roles in human and experimental arthritis have recently been defined [16, 17]: IL-7 stimulates the production of proinflammatory cytokines in experimental arthritis [18], influences ectopic lymphoid neogenesis [19], promotes osteoclastogenesis [20, 21], and abolishes the function of regulatory T cells (Treg) [22, 23]. Here, IL7 is linked to Arthritis.