Objective: To investigate the activity of Staphyloccocal enterotoxin A liposome (L-SEA) for inducing cytotoxicity of tumor infiltrating lymphocytes (TIL) against tumor cells.
Methods: TIL were isolated from the tumor tissues of five hepatocellular carcinoma patients. L-SEA, SEA and IL-2 were tested in vitro for their activity levels in stimulating TIL proliferation. The TNF-alpha and IFN-gamma secretion and cytotoxicity of TIL against HepG-2 liver cancer cells were estimated by ELISA and MTT, respectively.
Results: Both L-SEA and SEA significantly stimulated the proliferation of TIL. The cytokine secretion of L-SEA group was significantly higher than that of IL-2 group (P < 0.05). There was no significantly statistical difference in cytokine secretion between L-SEA group and SEA group (P > 0.05) except that IFN-gamma secretion of L-SEA group was lower than that of SEA group at day 4 (P < 0.05). Both L-SEA and SEA had potent ability to induce TIL cytotoxicity against HepG-2 cells. And no significant difference was observed between these two groups (P > 0.05).
Conclusion: These results suggest that L-SEA is as efficient as SEA in activating TIL.