Induction of proliferation of B prolymphocytic leukemia cells by phorbol
ester and native or recombinant interferon-gamma
RW Sauerwein, WG van der Meer and LA Aarden
Phorbol ester phorbol myristate acetate (PMA) induces proliferation in
nonmalignant human B cells and B cells from a patient with B prolymphocytic
leukemia (B-PLL). Mitogen-free T cell-derived conditioned medium acts
synergistically with PMA in inducing proliferation of B-PLL cells but does
not enhance the PMA-stimulated outgrowth of nonmalignant B cells.
Interleukin 2 (IL-2) has no effect on the outgrowth of B-PLL cells, and
monoclonal antibodies against the IL-2 receptor do not influence the
response to PMA and conditioned medium. Recombinant interferon-gamma
(IFN-gamma), in contrast, is a potent enhancer of PMA-induced proliferation
of B-PLL cells. With gel filtration techniques and with the use of
anti-IFN-gamma antibodies, it is shown that IFN-gamma in the conditioned
medium is responsible for the observed increase in B-PLL cell
proliferation. Preincubation of B- PLL cells with IFN-gamma induces
responsiveness to PMA, whereas IFN- gamma alone had no effect on these
cells when pretreated with PMA. The combined data show that, in the
presence of PMA, native and recombinant IFN-gamma are growth factors for B
cells from a B-PLL patient and that IL-2 is not involved in this process.
Volume 70,
Issue 3,
pp. 670-675,
09/01/1987
Copyright © 1987 by The American Society of Hematology
