Discordant effect of interferon on natural killer activity and tumor cell
sensitivity to lysis in hairy cell leukemia
N Lahat, E Aghai, A Kotler, A Kinarty, E Sobel, N Gruener and P Froom
Hematology Institute, Lady Davis Carmel Hospital, Haifa, Israel.
We studied the action of alpha-interferon (IFN) and interleukin-2 (IL- 2)
on natural killer (NK)-rich fractions and autologous tumor cells from two
patients with hairy cell leukemia (HCL). The addition of IFN or IL-2 to the
NK-rich fractions resulted in a significant increase in NK activity against
the autologous tumor cells. This stimulatory effect was blocked if the
target hairy cells (HCs) were preincubated with either IFN or IL-2.
Pretreatment of the HCs with anti-Tac antibody entirely prevented the
blocking effect of IL-2 and partially the blocking effect of IFN. One
patient was treated with recombinant alpha c-IFN. After 2 months there was
a dramatic reduction in the number of HCs in the peripheral blood
coincident with the loss of the protection effect of IFN against NK lysis
of the patient's HCs. NK activity against autologous tumor cells correlated
poorly with that against the K562 cell line. We conclude that there is a
discordant effect of IFN and IL-2 on NK activity and HC sensitivity to
lysis. The Tac receptor appears to play a role in this sensitivity. Caution
should be exercised in extrapolating the effects of NK activity against
K562 cells to those on HC targets.
Volume 71,
Issue 4,
pp. 1141-1143,
04/01/1988
Copyright © 1988 by The American Society of Hematology
