KLRA1P and rheumatoid arthritis: Such a paradigm, where Ly49+ T cells are long-lived, broadly active, and/or highly self-reactive cells regulated by inhibitory Ly49 receptors, agrees conceptually with recent work from the Cantor lab and others demonstrating that Ly49-expressing CD8αβ + T cells include or entirely comprise a regulatory population implicated in preventing or controlling such autoimmune diseases as systemic lupus erythematosus (SLE), multiple sclerosis (MS), and rheumatoid arthritis (RA) (123–125).