CD4 and neoplasm: Implantation of PK5L1940 pancreatic adenocarcinoma tumors results in a detectable peripheral blood CD8 T cell response to SIY (Supplementary Fig. S4a), and while anti-CD40L treated mice had a significant decrease in the number of tumor antigen-specific T cells in the peripheral circulation, CD4 depletion did not impact the CD8 T cell response (Supplementary Fig. S4a-b).