Dendritic Cells Pulsed with Pancreatic Cancer Total Tumor RNA Generate Specific Anti-Pancreatic Cancer T CellsIntroduction: RNA-based dendritic cell (DC) immunotherapy utilizing total tumor RNA provides the potential to generate a polyclonal immune repsonse to multiple known and unknown tumor antigens without HLA-restriction. Our study evaluated this approach as potential immunotherapy for pancreatic cancer patients. Methods: Matured DCs generated from peripheral blood of both healthy volunteers and pancreatic cancer patients were analyzed by flow cytometry for antigen-presenting phenotype. Immature DCs were transfected with mRNA encoding full length CEA Ag or pancreatic cancer total tumor RNA, then matured. Transfected, matured DCs were used to stimulate autologous T-cells and the resultant Ag-specific effector T cells were analyzed by IFN-γElispot assay. Results: Immature DCs with characteristic phenotypic markers CD40, CD80, and CD86 were successfully isolated from blood of pancreatic cancer patients. Incubation with maturation agents increased expression of CD80 and CD83 (5-and 7-fold, respectively), demonstrating a mature Ag-presenting phenotype. DCs transfected with a pancreatic cancer-associated antigen (CEA) generated antigen-specific T cells (p<0.05). DCs transfected with autologous total tumor pancreatic cancer RNA generated T-cells that specifically recognize HLA-matched pancreatic cancer cell lines (p<0.05 compared to control cell lines). Conclusions: DCs from pancreatic cancer patients maintain the ability to translate and process transfected RNA and serve as mature antigen presenting cells. These DCs succesfully generate specific T cells against the pancreatic cancer-associated antigen CEA, as well as T cells that specifically recognize pancreatic cancer. These data support the exploration of total tumor RNA pulsed DCs as a potential form of adjuvant immunotherapy for pancreatic cancer patients.
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