Description: The 53H5 monoclonal antibody reacts with human CD82, a 50-53 kDa protein belonging to the tetra-span (TM4) transmembrane proteins. CD82 is expressed broadly by the majority of hematopoietic lineages, but not erythrocytes. Activation of T and B lymphocytes upregulates CD82 expression. CD82 is also expressed by epithelial and endothelial cells and fibroblasts.