ABSTRACT
Fresh peripheral blood lymphocytes (PBL) are capable of lysing certain established tumor lines such as K562. Cells mediating this function have been designated natural killer (NK) cells. Anti-CD3 monoclonal antibody (moAb) acts as a mitogenic stimulus to PBL, inducing a proliferative response. The short-term culture of human PBLs with infiltrating lymphocytes (IL)-2 allows for the development of the ability to lyse NK-insensitive fresh tumor targets and some other tissues. Such cells have been designated lymphokine-activated killer (LAK) cells in some reports and have been associated with in vivo antitumor effects when combined with in vivo administration of IL-2. Murine immunotherapy models have shown that injection of antigen-specific T cells with IL-2 or cells with LAK activity with IL-2 can lead to a decrease in size or total elimination of established malignant tumors. Studies using short-term murine LAK cells activated with IL-2 have generally employed only 30 to 100 million cells to achieve significant antitumor effects.
