CD8A and neoplasm: Intermediate MC38 tumours (D14) begin to acquire features of a mature TME – with ECM remodelling and a shift in the composition and phenotype of infiltrating T cells towards effector populations – while late-stage tumours (D21) exhibit a mature TME reminiscent of human tumours, with desmoplasia, CD8+ T cell exhaustion, and T cell exclusion from the tumour core.