CD200R, also known as OX2R, is a membrane glycoprotein with up to 70% of its weight derived from N-linked glycosylation. CD200R is expressed primarily by monocytes and neutrophils but also by other leukocytes including T lymphocytes and mast cells. The interaction between CD200 and CD200R may contribute to pathways that suppress and limit macrophage induced inflammatory damage in tissue. Studies suggest that CD200-CD200R interaction may be involved in the control of myeloid cellular function. Levels of expression on resting peripheral blood cells are relatively low.