Lysis of Homologous Cells by Sensitized Lymphocytes in Tissue Culture2

Abstract

The effects of sensitized lymphocytes of BALB/c mice on homologous cells of the L strain, originally derived from a C3H mouse, were studied in a synthetic tissue-culture medium. The reaction between sensitized lymphocytes and the sensitizing homologous cells was characterized initially by a clustering of lymphocytes around the L cells. This was followed by marked and progressive cytopathogenic changes of the L cells, which finally resulted in destruction of most of these cells. The cytopathogenic and cytolytic effects occurred in the absence of complement. There was no demonstrable antibody bound to the L cells, as determined by the fluorescent-antibody technique. The serums of the sensitized mice did not contain antibodies demonstrable by precipitation, immunodiffusion, or fluorescent-antibody techniques. These observations demonstrated that cytolysis of homologous cells by sensitized lymphocytes occurs in vitro in the absence of classical humoral antibodies and further emphasized the importance of cellular phenomena in immune processes.