Dimethyl sulfoxide-induced inhibition of the immunosuppressive activity of cultured Friend erythroleukemia cells

Abstract

Two Friend leukemia virus-induced tumor cell lines lost their immunosuppressive properties in vitro when treated with dimethyl sulfoxide (DMSO), a known cellular differentiation agent. Incubation of the cell lines, GM 979 and GM 86, with DMSO for 4 days or longer, inhibited their ability to suppress the antibody forming capacity of normal murine spleen cells immunized in vitro with sheep red blood cells. Suppression of the inhibitory capability of the tumor cell lines by DMSO was time dependent. Three days incubation caused only slight, if any, inhibition, while a shorter period of treatment had no effect. Inhibition of the immunosuppressive properties of the tumor cell lines was not due to a decrease in tumor cell viability. The development of previously reported metabolic alterations in the treated cells, such as increased hemoglobin synthesis and other physicochemical alterations, paralleled cellular differentiation, and loss of immunosuppressive properties.