CD23 antibody is a 45-kDa glycoprotein that acts as a receptor for IgE. It is expressed by interleukin-4 activated B-lymphocytes, by activated macrophages, and by a proportion of follicular dendritic cells. CD23 overexpression has been observed on well-developed follicular dendritic cells in the germinal centers of lymph nodes from patients with Kimura’s disease. CD23, along with CD21, CD35 and vimentin, may be used to identify follicular dendritic cells. CD23 has been shown to aid in the differentiation of small lymphocytic lymphomas and mantle cell lymphoma.