Transcriptomic analysis of ChAdOx/MVA P1A vaccine-induced P1A-35-43-specific CD8+ T-cells by single-cell RNA-sequencing

This study aimed to analyze the transcriptional profiles of ChAdOx/MVA vaccine induced P1A-35-43-specific CD8+ T-cells and how this is affected by both tissue location and anti-PD-1 treatment. 15V4T3 tumour-bearing DBA/2 mice were vaccinated with ChAdOx/MVA P1A with or without anti-PD-1 treatment. Following treatment, spleens and tumours were collected, processed to single-cell suspension and P1A-35-43-specific CD8+ T-cells were then isolated by MHC-class I multimer staining and FACS. Single-cell RNA-seq experiments were performed using the 10X Genomics platform to analyze P1A-specific CD8+ T-cell transcriptional profiles. Results of this transcriptomic analysis showed that cells segregated into distinct phenotypic subtypes reflecting either effector or stem-like states, the distribution of which was dependent on tissue of origin and treatment status. These results provide an in depth phenotypic analysis of MAGE-type-antigen-specific CD8+ T-cells induced by ChAdOx/MVA vaccination and how phenotype is influenced by physiological location and immune checkpoint blockade treatment. 15V4T3-tumour-bearing mice were treated with either ChAdOx/MVA P1A vaccination, or with ChAdOx/MVA P1A + anti-PD-1 combination. Following treatment, P1A-35-43-specific CD8+ T-cells were isolated from spleens and tumours by MHC-class I multimer staining and FACS sorting. Single-cell RNA-seq experiments were performed using the 10X Genomics platform to analyze the transcriptional profile of P1A-specific CD8+ T-cells.