An improved method for the generation of human lymphokine activated killer cells

In an effort to make interleukin-2/lymphokine-activated killer cell (IL-2/LAK) therapy safer for cancer patients, we examined the efficacy of using Fenwal PL732 bags as tissue culture flasks. These bags can be sterilly connected using tubing kits thus reducing the risk of contamination to the cells. Peripheral blood mononuclear cells were obtained from normal donors or cancer patients undergoing IL-2/LAK cell therapy. Following Ficoll-Hypaque purification, these cells were incubated in the presence of IL-2 in either PL732 plastic bags or standard tissue culture flasks. Our results showed that LAK cells could be generated from either normal donors or cancer patients in the bags as well as in the flasks. Comparisons were made of the LAK cell populations obtained from the two sources and showed that each was similar in terms of morphology as determined by Wright stain differentials. The populations of cells were also similar in regard to cell surface phenotype as determined by flow cytometric analysis. In addition, recoveries from either tissue culture vessel as well as cell viability of the LAK cells were comparable. Finally, the LAK cells obtained from both sources were assessed for cytolytic activity against the tumor cell lines K562 and Daudi. These results showed that the cytolytic activity of the LAK cells against these target cells was the same whether the cells were obtained from the flasks or the bags.