Augmentation of ADCC and cytotoxic T-cell activity with ImuVert.

We previously reported that natural killer cell activity of peripheral blood mononuclear cells (PBMC) from healthy human subjects was augmented following in vitro incubation in ImuVert, a biologic response modifier derived from the bacterium Serratia marcescens. In the current investigation, we found that exposure of PBMC to ImuVert, 3-40 micrograms/ml, for 18 hr, resulted in significant and dose-dependent augmentation of three other types of cell-mediated cytotoxicity: K cell-mediated antibody-dependent cellular cytotoxicity (ADCC), monocyte-mediated ADCC, and cytotoxic T-cell activity against allogeneic PBMC. These and previous findings suggest that ImuVert may have a broad range of stimulatory effects on immune function.