CD200 and allergic disease: For instance, soluble CD200 constructs, as well as an agonistic monoclonal antibody directed at CD200R1, have shown promise in pre-clinical experimental models of autoimmune encephalomyelitis14 and autoimmune uveoretinitis18 (in prolonging the survival of allografts6) and of collagen-induced arthritis.17, 48 It is reasonable, therefore, to consider the CD200:CD200R1 axis as a target for repression of inflammatory responses with potential application in allergy, autoimmunity, and transplantation.