Activation of CD20, a cross-membrane ion channel, induces cell cycle progression from G0 to G1 in B lymphocytes. Subsequent activation of CD40, a membrane receptor of the nerve growth factor receptor superfamily, transits the B cells to the S phase. CD40 may also act synergistically in combination with IL-4 (B lymphocytes) or IL-3/IL-7 (B-cell precursors). We investigated the proliferative responses of B-lineage acute lymphoblastic leukaemia (ALL) cells to CD20/CD40 activation. In 18/56 ALL cases, CD20 activation resulted in significant increases in DNA synthesis. Similar, although more moderate, effects were seen of activation of CD40 in 10/44 cases. Responses to CD20 or CD40 activation were independent of co-stimulation with IL-3, IL-4 or IL-7, and various cocktails of the different growth stimuli did not act synergistically.

acute lymphoblastic leukaemia, CD20, CD40, in vitro proliferation,
British Journal of Haematology
Department of Hematology

Smiers, F.J.W, van Paassen, M, Hählen, K, Löwenberg, B, & Touw, I.P. (1996). CD20 and CD40 mediated mitogenic responses in B-lineage acute lymphoblastic leukaemia. British Journal of Haematology, 93(1), 125–130. doi:10.1046/j.1365-2141.1996.4781011.x