MKI67 and neoplasm: Differences in proliferation in the steady state could not explain the different radiosensitivity of T cells from lymphoid versus non-lymphoid tissues and tumor either, since Ki67 levels were highest for intratumoral parenchymal CD8+ T cells and similar for lymphoid and non-lymphoid tissue-parenchymal CD8+ T cells (Supplementary Fig. 7), and thus did not correlate with sensitivity to IR.