CD200R1 and allergic disease: The physiological importance of this immuno-inhibitory pathway has been demonstrated in several inflammation models, including, but not limited to, experimental asthma,5 transplantation,6, 7, 8, 9 inflammatory bowel disease,10 neuropathic pain,11 systemic lupus erythematosus,12 arthritis,13 and multiple sclerosis.14, 15 Consequently, the development of CD200R1-specific agonists for treating inflammatory conditions (e.g., autoimmunity, transplantation, airway hyper-responsiveness, and allergy) is of clinical importance.