ENHANCED LYMPHOKINE-ACTIVATED KILLER-CELL ACTIVITY BY AN IMMUNOMODULATOR, ROQUINIMEX

Roquinimex (Roq) is an immunomodulator known to stimulate cellular imm une responses. It is currently used for immunotherapy after bone marro w transplantation (BMT). One of the major features of this compound is an enhancement of natural killer (NK) cell activity and numbers. We s tudied the in vitro effect of Roq on human peripheral blood NK and adh erent lymphokine-activated killer cell (ALAK) activities. In cultures supplemented with recombinant interleukin 2 (rIL-2) (1000 U ml(-1)) an d Roq a significant increase in NK and LAK function was observed witho ut a parallel increase in cell numbers. We also examined the generatio n of NK cells from human bone marrow (BM) immature progenitors, obtain ed by purging with 4-hydroperoxycyclophosphamide (4HC). NK cell number s and activity were both increased when cultures with rIL-2 (10 U ml(- 1)) were supplemented with Roq. These results confirm findings obtaine d in vivo and in vitro in the murine system and suggest that Roq is an active agent on these lymphoid populations. These properties and good tolerability make Roq an attractive tool for immunotherapy.