HUMAN PANCREATIC-CANCER CELLS (MPANC-96) RECOGNIZED BY AUTOLOGOUS TUMOR-INFILTRATING LYMPHOCYTES AFTER IN-VITRO AS WELL AS IN-VIVO TUMOR EXPANSION

A human tumor line designated MPanc-96 has been established from a poo rly differentiated primary pancreatic adenocarcinoma MPanc-96 has a do ubling time of 27 hr and grows as a confluent monolayer in various cul ture media. Cytogenetic analysis of in vitro-cultured tumor cells reve aled a large number of clonal chromosomal aberrations, confirming thei r neoplastic origin. MPanc-96 grows in SCID mice when injected s.c. Xe nografts established from the tumor line had a similar histology as th e primary tumor. Tumor-infiltrating lymphocytes (TILs) were isolated f rom the primary tumor, and cytotoxic T lymphocytes (CTLs) were generat ed after activation on immobilized anti-CD3 monoclonal antibody (MAb) for 48 hr, expansion in low-dose lL-2 and repeated stimulation with ir radiated MPanc-96 tumor cells. The generated CTLs lysed fresh autologo us tumor cells as well as in vitro and in vivo expanded tumor cells fr om passages 9-53, suggesting that one or more tumor-associated antigen s (TAAs) are stably expressed. CTLs lysed tumor cells in an HLA-class I-restricted fashion but showed no significant cytotoxicity against au tologous fibroblasts, several allogeneic pancreatic cancer cell lines or K562. Our findings may be significant for the design of an animal m odel for studying the mechanisms of immunotherapy in human pancreatic cancer or for the identification of TAAs in pancreatic cancer. (C) 199 7 Wiley-Liss, Inc.