Natural cytotoxicity: recent progress and continuing controversy

These highlights of the presentations and discussions at the Second International Workshop on Natural Killer Cells demonstrate the rapid progress that is being made in our understanding of the fundamental nature and mechanism of action of natural killer cells. Although the workshop was purposefully directed to fundamental studies, it is clear that these research efforts will soon have a substantial impact at the clinical level. For example, E. Lotzová (Houston, Tex., USA) noted that several experimental measures of NK function are altered in patients suffering from myelogenous leukemia. NK cells isolated from these patients demonstrate reduced conjugate formation, a substantial reduction in the Vmax for lysis of K-562 cells, could not recycle and were deficient in production of NKCF. She also presented preliminary data that cytotoxic activity could be restored by partially purified alpha interferon and IL-2. A book based on the proceedings of this workshop will soon be published by Academic Press.