Figure 2.

Inhibitory receptor expression in murine TIL exceeds peripheral T cells

a) Moc2 and Moc22 tumors were established to a palpable subcutaneous tumor in C57BL/6 animals for 12 d prior to tumor harvest and plating for TIL expansion. Blood was obtained from time of harvest for a peripheral T cell control. b and c) Inhibitory receptor expression in Moc22 and Moc2 CD8⁺ TIL relative to blood. Blood: n = 5, TIL: Moc22 n = 34 cultures from 21 mice, combined from two independent experiments, Moc2 n = 10 cultures from 5 mice. d) Pmel-1 transgenic mice were inoculated with B16F10 melanoma tumor. Transgenic T cells infiltrating tumors or spleens were expanded ex vivo and characterized. e and f) Surface expression of inhibitory receptors after 3–4 weeks of expansion in IL-2. Spleen n = 5 mice, TIL cultures n = 23 from three mice. Statistical tests: c,f) Mann Whitney U test; ns not significant, *p < .01, ***p < .001, ****p < .0001.