Expansion of cytotoxic CD3(+)CD56(+) cells from peripheral blood progenitor cells of patients undergoing autologous hematopoietic cell transplantation

Immunotherapy may potentially improve the outcome of autologous hematopoiet ic cell transplantation (HCT). Poor effector cell proliferation and margina l antitumor activity limit attempts to use immunotherapy. We have character ized the ex vivo expansion, up to 1000-fold, of CD3(+)CD56(+) lymphocytes f rom the peripheral blood lymphocytes (PBL) of healthy donors. Expanded cell s termed cytokine-induced killer (CIK) cells induce non-major histocompatib ility complex-restricted lysis of tumor cells and demonstrate cytolytic act ivity superior to lymphokine-activated killer cells without the requirement of interleukin (IL)-2 treatment in vivo. To determine whether cytolytic ce lls could be expanded from patient material, we evaluated samples of periph eral blood progenitor cells (PBPCs) from 25 patients undergoing autologous HCT. The PBPCs were expanded by priming with interferon-gamma followed by a nti-CD3 monoclonal antibody and IL-2 the next day. Fluorescence-activated c ell sorting analysis was performed on days 0, 15, 21, and 28 of cell cultur e. The median T-cell content rose from 15.3% (range, 1.1% to 89.7%) on day 0 to 97.2% (range, 83.6% to 99.5%) by day 15. By day 21, T cells expanded 2 1.8-fold (range, 1.7- to 420.0-fold) and CD3(+)CD56(+) cells expanded 44.8- fold (range, 5.1- to 747.0-fold). CIK cells were used as effector cells aga inst B-cell lymphoma targets (OCI-Ly8) with a median of 24% (range, 3% to 6 7%) and 42% (range, 6% to 96%) specific lysis of target cells on days 21 an d 28, respectively. CIK cells derived from PBL of 2 additional patients wit h acute myelogenous leukemia demonstrated 39% and 78% specific lysis of OCI -Ly8 and 26% and 58% specific lysis of autologous leukemic blasts at an eff ector:target ratio of 40:1. CIK cells may be expanded from granulocyte colo ny-stimulating factor-mobilized PBPCs of patients undergoing posttransplant ation adoptive immunotherapy.