Naive T cell tumor infiltration and intratumoral activation does not require the presence of CD44^hi cells. (A) Expression of CD44 on CD8 cells from pooled LN and spleen of an OT-I Thy1.1⁺ mouse. (B) A 70:30 mixture of CFSE-labeled, CD44-depleted, and unlabeled bulk OT-I cells was transferred into Thy1-mismatched mice bearing established s.c. (C) or i.p. (D) tumors. 24 h after transfer, tumors, LN, and spleen were harvested and lymphocytes were stained for flow cytometry. Plots are gated on Thy1.1⁺ CD8⁺ lymphocytes. Numbers in the top row indicate the percentage of either CD44-depleted or bulk CD8 cells. Axes on plots are displayed in Logicle scale. Numbers in the bottom row indicate the percentage of each population that is CD69⁺. Results represent n = 4 mice per tumor location in 2 independent experiments.