Objective: To investigate the influence of fibronectin (FN) on cytotoxicity and adhesion of tumor-infiltrating lymphocytes (TIL) from oral squamous cell carcinoma (OSCC).
Materials and methods: TIL cells were isolated from surgical specimens of 9 patients with OSCC. Specific cytotoxicity for autologous tumor cells were tested by 3H-TdR 4 hours release, and specific TNF-alpha release was detected using enzyme-linked immunosorbent assay. Expression of intercellular adhesion molecule-1 (ICAM-1) and lymphocyte function-associated antigen-1 (LFA-1) on TIL cells were analyzed on FACScan following incubation with FITC-conjugated antibody. Cell adhesion ability was evaluated through detection by optical density (OD) values of bound cells and unbound cells.
Results: TIL-specific cytotoxic activity for autologous tumor was significantly enhanced, ranging from 17.7% to 67.6% by incubation on FN (P < 0.005). Cell adhesion was increased ranging from 42.5% to 62.7% by coculturing with FN (P < 0.005). The interaction of TIL with FN increased expression of ICAM-1 and LFA-1 on TIL cells as well. But specific TNF-alpha release was not obviously changed by FN (P > 0.5).
Conclusion: The enhanced TIL activity by FN might be mediated by increased binding of TIL to targets through adhesion strengthening. This culture system would be useful to improve the TIL generation for cancer therapy.