Specificity: This antibody reacts with 35 kD antigen present on the nuclear membrane protein related to the invariant chain of the HLA-Dr antigen. This antibody reacts with the germinal center and mantle zone B lymphocytes, interdigitating histiocytes in T cell zones and mononuclear cells and Reed-Sternberg cells in Hodgkin's disease. Molecular Weight: 35 kD