Vaccine-induced neoantigen T cells migrate into the tumor. A, T-cell response assessed by ex vivo ELISpot versus percentage changes in target lesion size (sum of target lesion measurements evaluated per RECIST v1.1.) from baseline are displayed for NOUS-PEV Pt 1. B, Deconvolution of T-cell response by ex vivo ELISpot against individual peptides of the immunogenic pool 1. The immunogenic NeoAg7 is shown in black. The unpaired t test was used to make comparisons (****, P < 0.0001). C, Top, schematic representation of the IVS protocol to expand vaccine induced neoantigen specific T cells against NeoAg7 peptide. Bottom, T-cell responses in Pt 1 measured by IFNγ ELISpot assay after IVS with NeoAg7 peptide. Tested PBMCs were collected after pembrolizumab (week 10) and after vaccination (week 14). The unpaired t test was used to make comparisons (***, P < 0.001). D, Expansion and diversification of TCRβ repertoire in pre- and posttreatment tumor biopsies of Pt 1. Each bar is a TCRβ individual clone; the clonotypes specific for NeoAg7 detected on the tumor biopsies of Pt 1 are shown as black bars.