Extended Data Fig. 7. Vaccine specific responses in skin.

a) IDO and PD-L1 specific T cell responses in SKILs after 6 series of treatment measured by IFN-γ Elispot assay (n=13). SKILs were grown from DTH injection with either IDO peptide, PD-L1 peptide or a mix as presented by different blue colours. * Responses were calculated as the difference between average numbers of spots in wells stimulated with IDO or PD-L1 peptide (triplicates) and corresponding control (DMSO) and statistical analyses of Elispot responses were performed using distribution-free resampling method (Moodie et al.). DR: Not statistically confirmed response due to replicate number but number of spots in peptide wells are two times higher than control wells (DMSO). NS: No significant response and no DR. b/c/d) Percentage of cytokine secreting/CD107a+ CD4+ and CD8+ IDO and PD-L1 specific T cells in response to in vitro peptide stimulation by flow cytometry. e) Skin infiltrating PD-L1 specific T cell clones also found in biopsy in patient MM01. TCR sequencing was performed on a PD-L1 specific T cell culture generated from DTH area on the lower back injected with PD-L1 peptide on patient MM01. Bars show the frequency of top 25 clones in the culture with which indicates a high Simpson clonality of 0.43. f) Tracking the frequency of the top five skin infiltrating PD-L1 specific clones in tumour before and after treatment.