CD23 (BLAST 2, FC epsilon RII, IgE binding factor, IgE receptor lymphocyte, Immunoglobulin E receptor low affinity II)

CD23 (45 kDa) is described as a protein found on the surface of IgM bearing B cells, eosinophils, macrophages and some T and NK cells. Elevated levels of CD23 have been found in samples from people with B cell-derived Chronic Lymphocytic Leukemia, Hyper IgE Syndrome and post-Bone Marrow Transplantation samples. CD23 levels may be related to the disease course in Hairy Cell Leukemia.