CD20 and CD40 mediated mitogenic responses in B-lineage acute lymphoblastic leukaemia.
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.
Smiers
F J
FJ
Department of Haematology, Dr Daniel den Hoed Cancer Centre, Erasmus University, Sophia Children's Hospital, Rotterdam, The Netherlands.
van Paassen
M
M
Hählen
K
K
Löwenberg
B
B
Touw
I P
IP
D018951:Antigens, CD20 / Q000276:immunology*; D002051:Burkitt Lymphoma / Q000276:immunology*; D019013:CD40 Antigens / Q000276:immunology*; D002455:Cell Division / Q000276:immunology; D004247:DNA / Q000096:biosynthesis*; D005434:Flow Cytometry; D006801:Humans; D007377:Interleukin-3 / Q000494:pharmacology; D015847:Interleukin-4 / Q000494:pharmacology; D015851:Interleukin-7 / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D018951:Antigens, CD20; D019013:CD40 Antigens; D007377:Interleukin-3; D015851:Interleukin-7; D015847:Interleukin-4; D004247:DNA