4-1BB Agonist Focuses CD8+ Tumor-Infiltrating T-Cell Growth into a Distinct Repertoire Capable of Tumor Recognition in Pancreatic Cancer

Clin Cancer Res. 2017 Dec 1;23(23):7263-7275. doi: 10.1158/1078-0432.CCR-17-0831. Epub 2017 Sep 25.

Abstract

Purpose: Survival for pancreatic ductal adenocarcinoma (PDAC) patients is extremely poor and improved therapies are urgently needed. Tumor-infiltrating lymphocyte (TIL) adoptive cell therapy (ACT) has shown great promise in other tumor types, such as metastatic melanoma where overall response rates of 50% have been seen. Given this success and the evidence showing that T-cell presence positively correlates with overall survival in PDAC, we sought to enrich for CD8+ TILs capable of autologous tumor recognition. In addition, we explored the phenotype and T-cell receptor repertoire of the CD8+ TILs in the tumor microenvironment.Experimental Design: We used an agonistic 4-1BB mAb during the initial tumor fragment culture to provide 4-1BB costimulation and assessed changes in TIL growth, phenotype, repertoire, and antitumor function.Results: Increased CD8+ TIL growth from PDAC tumors was achieved with the aid of an agonistic 4-1BB mAb. Expanded TILs were characterized by an activated but not terminally differentiated phenotype. Moreover, 4-1BB stimulation expanded a more clonal and distinct CD8+ TIL repertoire than IL2 alone. TILs from both culture conditions displayed MHC class I-restricted recognition of autologous tumor targets.Conclusions: Costimulation with an anti-4-1BB mAb increases the feasibility of TIL therapy by producing greater numbers of these tumor-reactive T cells. These results suggest that TIL ACT for PDAC is a potential treatment avenue worth further investigation for a patient population in dire need of improved therapy. Clin Cancer Res; 23(23); 7263-75. ©2017 AACR.

MeSH terms

  • Antibodies, Monoclonal / immunology
  • Antibodies, Monoclonal / pharmacology
  • CD8-Positive T-Lymphocytes / drug effects
  • CD8-Positive T-Lymphocytes / immunology
  • Cell Line, Tumor
  • Cell Proliferation / drug effects
  • Humans
  • Immunotherapy, Adoptive / methods*
  • Linear Models
  • Lymphocytes, Tumor-Infiltrating / immunology
  • Lymphocytes, Tumor-Infiltrating / transplantation*
  • Pancreatic Neoplasms / immunology
  • Pancreatic Neoplasms / pathology
  • Pancreatic Neoplasms / therapy*
  • Tumor Necrosis Factor Receptor Superfamily, Member 9 / agonists
  • Tumor Necrosis Factor Receptor Superfamily, Member 9 / immunology*

Substances

  • Antibodies, Monoclonal
  • TNFRSF9 protein, human
  • Tumor Necrosis Factor Receptor Superfamily, Member 9