Induction and Analysis of Cytotoxic T-Lymphocytes that Recognize Autologous Oral Squamous Cell Carcinoma

Abstract

Background: It is essential that cytotoxic T-lymphocytes (CTLs) recognize tumor-associated antigens (TAAs) and exhibit antitumor effects in immunological responses for tumor rejection. However, only a few cases with oral squamous cell carcinoma (OSCC) have been studied for these antitumor mechanisms. We established a cancer cell line and autologous CTL pair for identifying TAAs in OSCC, despite difficulties in establishing such a pair.

Materials and methods: A cell line (OTM) from a primary lesion and a CTL line (TcOTM) were derived from OSCC in a 64-year-old female patient. CTL clones were generated by repetitive limiting dilutions. Accurate characterization was performed by in vitro analysis.

Results: The TcOTM clone showed specific cytotoxic activity against OTM cells in an human leukocyte antigen (HLA)-A24-restricted manner. Furthermore, it exerted cytotoxicity against the allogenic HLA-A24 cell lines.

Conclusion: These data indicated that the TcOTM clone recognized a TAA presented by HLA-A24 cells. This unique method will allow for identification of unknown TAAs for OSCC in the future.

Keywords: CTL; HLA-A24; Oral cancer; autologous tumor–CTL pair; oral squamous cell carcinoma; tumor antigen.