BER - H 2 : A New Anti - Ki - 1 ( CD 3 O ) Monoclonal Antibody Directed at a Formol - Resistant Epitope

The production and characterization of a monoclonal antibody (MoAb) designated Ber-H2. directed against a new epitope of the Ki-1 (CD3O) antigen. are described. In comparison with the formerly reported Ki-1 MoAb whose reactivity with Hodgkin and Reed-Sternberg (H-RS) cells in frozen tissue sections is well-documented. the Ber-H2 MoAb showed new. important features: the labeling intensity of the Ber-H2 MoAb was much stronger. and the number of positively labeled cells was higher. Most important. however, was that the Ber-H2 MoAb could be applied in routinely processed. formaldehyde-fixed. paraffinembedded tissue sections. Therefore, it was possible to investigate an unprecedented number of tumors received as frozen or formaldehyde-fixed material for expression of the CD3O antigen. Beside Hodgkin’s disease. the Ber-H2 MoAb labeled a variable number of cells in lymphomatoid papulosis. peripheral T-ceIl lymphomas. and angoimmunoblastic lymphadenopathy. Among B-cell non-Hodgkin’s lymphomas (NHLs). some cases containing large centro-