Establishment of Mouse Lymphokine‐activated Killer Cell Clones and Their Properties

To assess the properties of lymphokine‐activated killer (LAK) cells, we established mouse LAK cell clones from LAK cell lines induced from C57BL/6 mouse spleen cells. Although these clones expressed similar phenotypes to the parent LAK cells, Lyt‐2 was expressed in a restricted portion of the clones. All clones were found to express T3 CD(3) and T cell receptor (TcR) αβ on their cell surface. Rearrangement patterns of TcR were the same among the clones derived from the same parent cell line but differed in those from different cell lines as determined by using Cβ(1) and Jβ probes. The molecules responsible for LAK‐target cell binding were examined by using a monoclonal antibody (mAb) against lymphocyte function associated antigen 1 (LFA‐1). This mAb (termed KBA) showed inhibitory effects on both LAK‐target cell binding and cytolytic activity of LAK cell clones, indicating a principal role of LFA‐1 in LAK cell clones. The magnitude of perform mRNA expression in LAK cell clones was unrelated to their cytolytic activities.