Expansion of Tumor-reactive T Cells From Patients With Pancreatic Cancer

Generation of T lymphocytes with reactivity against cancer is a prerequisite for effective adoptive cellular therapies. We established a protocol for tumor-infiltrating lymphocytes (TILs) from patients with pancreatic ductal adenocarcinoma. Tumor samples from 17 pancreatic cancer specimens were cultured with cytokines (IL-2, IL-15, and IL-21) to expand TILs. After 10 days of culture, TILs were stimulated with an anti-CD3 antibody (OKT3) and irradiated allogeneic peripheral blood mononuclear cells. Reactivity of TILs against tumor-associated antigens (mesothelin, survivin, or NY-ESO-1) was detected by intracellular cytokine production by flow cytometry. Cytotoxicity was measured using a Chromium 51 release assay, and reactivity of TILs against autologous tumor cells was detected by INF- production (ELISA). TIL composition was tested by CD45RA, CCR7, 4-1BB, LAG-3, PD-1, TIM3, and CTLA-4 marker analysis. TCR V was determined by flow cytometry and TCR clonality was gauged measuring the CDR3 region length by PCR analysis and subsequent sequencing. We could reliably obtain TILs from 17/17 patients with a majority of CD8(+) T cells. CD3(+)CD8(+), CD3(+)CD4(+), and CD3(+)CD4(-)CD8(-) [double-negative (DN) T cells] resided predominantly in central (CD45RA(-)CCR7(+)) and effector (CD45RA(-)CCR7(-)) memory subsets. CD8(+) TILs tested uniformly positive for LAG-3 (about 100%), whereas CD4(+) TILs showed only up to 12% LAG-3(+) staining and PD-1 showed a broad expression pattern in TILs from different patients. TILs from individual patients recognized strongly (up to 11.9% and 8.2% in CD8(+)) NY-ESO-1, determined by ICS, or mesothelin, determined respectively by TNF- and IFN- production. Twelve of 17 of CD8(+) TILs showed preferential expansion of certain TCR V families (eg, 99.2% V13.2 in CD8(+) TILs, 77% in the V1, 65.9% in the V22, and 63.3% in the V14 family). TCR CDR3 analysis exhibited monoclonal or oligoclonal TCRs, some of them (eg, CD8(+) V13.2) reacting strongly against autologous tumor defined by INF- production or by cytotoxicity. We have optimized methods for generating pancreatic cancer-specific TILs that can be used for adoptive cellular therapy of patients with pancreatic cancer.