CD8A and cancer: Yoon et al.’s murine model isolated two specific B. breve species that were able to improve anti-tumour immunity when used in combination with anti-cancer therapeutics such as oxaliplatin and PD-1 blockade as measured through increased CD4+/Treg, CD8+/Treg and effector CD8+/Treg as well as increased intra-tumour cytokine expression [112].