Rheumatoid arthritis is an autoimmune disease characterized by chronic joint inflammation and subsequent destruction of the associated cartilage and bone. In May Nature Medicine Mario Delgado and colleagues from Complutense University, Madrid show that administration of the vasoactive intestinal peptide (VIP) can modulate the mechanisms of the disease and could be the basis for a new treatment for arthritis.

Using a murine model of arthritis, Delgado et al demonstrated that intravenous treatment with VIP delayed onset of the disease by preventing joint swelling and destruction of cartilage and bone. The therapeutic effect of VIP was associated with downregulation of mRNA expression for the proinflamatory factors TNF-α, IL-6, IL-12, IL-18, IL-1β and IL-1α. VIP also regulated the Th1/Th2 lymphocyte balance, inhibiting Th1 and autoimmune responses (Nat Med 2001, 7:563-568).

In an accompanying News & Views article Gary Firestein from UCSD School of Medicine La Jolla, California says...