Effect of interleukins on the proliferation and survival of B cell chronic lymphocytic leukaemia cells.
OBJECTIVE
To investigate the effects of interleukin (IL) 1, 2, 4, and 5 on the proliferation and survival of peripheral blood B cells from patients with B chronic lymphocytic leukaemia (B-CLL) and compare them with the effects on normal peripheral blood B cells.


METHODS
The proliferation and survival of pokeweed mitogen (PWM) activated B cells from B-CLL (n = 12) and normal peripheral blood (n = 5) were studied in vitro in response to IL-1, IL-2 IL-4, and IL-5. Survival of cells in cultures with or without added interleukins was studied by microscopic examination of cells and DNA agarose gel electrophoresis.


RESULTS
Proliferation was observed in both B-CLL and normal peripheral blood cells on culture with IL-2 alone and also in some, but not all, B-CLL and normal peripheral blood cells with IL-1 and IL-4. However, there was greater variability in B-CLL cell responses than in normal peripheral blood cells. Il-5 did not affect normal peripheral blood cell proliferation but it increased proliferation in two B-CLL cases. Synergistic effects of these cytokines were not detected. IL-4 inhibited normal peripheral blood and B-CLL cell proliferation after the addition of IL-2. Inhibition of B-CLL cell responses to IL-2 was also observed with IL-5 and Il-1. Survival of B-CLL cells in cultures was enhanced with IL-4 not by an increase in proliferation but by reduced apoptosis. No such effect was seen in normal peripheral blood cells. IL-2 had a less noticeable antiapoptotic effect; IL-5 enhanced apoptosis in B-CLL cells.


CONCLUSIONS
B-CLL and normal peripheral blood cells proliferated equally well in response to IL-2. IL-4 had a much lower effect on B-CLL cell proliferation, but had noticeable antiapoptotic activity. IL-5 enhanced cell death by apoptosis.
Mainou-Fowler
T
T
Department of Haematology, Derriford Hospital, Plymouth.
Copplestone
J A
JA
Prentice
A G
AG
D017209:Apoptosis; D002455:Cell Division; D002470:Cell Survival; D004587:Electrophoresis, Agar Gel; D006801:Humans; D016130:Immunophenotyping; D007375:Interleukin-1 / Q000494:pharmacology; D007376:Interleukin-2 / Q000494:pharmacology; D015847:Interleukin-4 / Q000494:pharmacology; D015848:Interleukin-5 / Q000494:pharmacology; D007378:Interleukins / Q000494:pharmacology*; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000097:blood* / Q000276:immunology; D011994:Recombinant Proteins / Q000494:pharmacology; D014407:Tumor Cells, Cultured
D007375:Interleukin-1; D007376:Interleukin-2; D015848:Interleukin-5; D007378:Interleukins; D011994:Recombinant Proteins; D015847:Interleukin-4