Effect of culture media on lymphokine-activated killer effector phenotype and lytic capacity.

We compared the ability of murine lymphokine-activated killer (LAK) cells grown in either a serum-supplemented "standard" medium (alpha MEM plus fetal calf serum) or a serum-free medium (AIM-V) to lyse a range of tumour targets. LAK cells grown in either of the media killed a cultured murine tumour line (YAC-1 lymphoma) well and spared syngeneic "self" cells (concanavalin-A-stimulated splenocytes). However, a striking difference was noted in the ability of LAK cells grown in alpha MEM plus fetal calf serum (as opposed to AIM-V) to kill "modified self" cells (trinitrophenol-modified concanavalin A blasts); LAK cells grown in the former always killed modified self cells better than those grown in the latter. This pattern held under a broad range of experimental manipulations and was found to be related to a relative increase in CD3-bearing LAK cells grown in the standard medium. These data suggest that the two media cannot be used interchangeably. This conclusion may have clinical implications for the use of LAK cells, as animal studies have been done using LAK cells generated in serum-containing medium and clinical studies have used LAK cells generated in serum-free medium.