Bone marrow and peripheral blood natural killer cell activity in lymphomas. Its response to IL-2

Abstract

SUMMARYNatural killer (NK) cytotoxic activity was simultaneously investigated in bone marrow mononuelear cells (BMMC) and peripheral blood lymphocytes (PBL) from nine Hodgkin's disease (HD) and 15 non-Hodgkin lymphoma (NHL) untreated patients. Twenty-five PBL samples and seven bone marrow specimens from healthy individuals were also included as control group (C). NK cell activity was evaluated in basal condition and post-stimulation with human recombinant IL-2 {rIL-2). Dala were expressed in lvalues (number of BMMC or PBL needed to lyse 5O' .^i of the target cells). In basal condition, both HD and NHL palients showed a NK cell activity comparable to the C group, both in BMMC (HD, A: = 2-48±1-3; NHL. A:=3-8±2O; C, K=3-2±O7) and PBL (HD, K=20±l-Q; NHL, K=2-i±\Q; C, K=2-2±(i-2).Stimulation with rIL-2 induced a significant and comparable enhancement of the NK activity in PBL from HD, NHL and C while the response to r!L-2 of the BMMC in most of the HD and NHL patients was significantly greater than the C group. Responder ceils were characterized by negative selection with specific MoAb plus complement as a CD3 , CDI6*, CD56' cytotoxic cell and further confirmed by flow cytometry. We postulate that IL-2 activation of bone marrow NK cell precursors, in addition to enhancing the activity of circulating NK, may be dT value for the therapeutic rationale of lL-2 in patients with lymphoma.