[Studies of mast cell-mediated cytotoxicity to hepatoma cells in vitro].

The effects of mast cells (MCs) isolated from rat peritoneal cavity on rat hepatoma cell line (CBRH7919) in vitro were studied with phase contrast microscopy, scanning and transmission electron microscopy. The results showed that different degrees of degeneration were present in all CBRH7919 cells and a few of them exhibited necrosis or disruption when CBRH7919 cells were cocultured with MCs for 24 hours. In situ hybridization demonstrated that the expression of c-myc mRNA in CBRH7919 cells was markedly reduced by MCs. MTT colorimetric assay indicated that the supernatants of MC cultures had suppressive effect on the proliferation of CBRH7919. A monoclonal anti-mouse TNF antibody could decrease the suppressive effect. These results suggest that MCs had anti-tumor effect.