1. Intratumoral CD8+T cells with a tissue-resident memory phenotype mediate local immunity and immune checkpoint responses in breast cancer
- Author
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Virassamy, B, Caramia, F, Savas, P, Sant, S, Wang, J, Christo, SN, Byrne, A, Clarke, K, Brown, E, Teo, ZL, von Scheidt, B, Freestone, D, Gandolfo, LC, Weber, K, Teply-Szymanski, J, Li, R, Luen, SJ, Denkert, C, Loibl, S, Lucas, O, Swanton, C, Speed, TP, Darcy, PK, Neeson, PJ, Mackay, LK, Loi, S, Virassamy, B, Caramia, F, Savas, P, Sant, S, Wang, J, Christo, SN, Byrne, A, Clarke, K, Brown, E, Teo, ZL, von Scheidt, B, Freestone, D, Gandolfo, LC, Weber, K, Teply-Szymanski, J, Li, R, Luen, SJ, Denkert, C, Loibl, S, Lucas, O, Swanton, C, Speed, TP, Darcy, PK, Neeson, PJ, Mackay, LK, and Loi, S
- Abstract
CD8+ tumor-infiltrating lymphocytes with a tissue-resident memory T (TRM) cell phenotype are associated with favorable prognosis in patients with triple-negative breast cancer (TNBC). However, the relative contribution of CD8+ TRM cells to anti-tumor immunity and immune checkpoint blockade efficacy in breast cancer remains unknown. Here, we show that intratumoral CD8+ T cells in murine mammary tumors transcriptionally resemble those from TNBC patients. Phenotypic and transcriptional studies established two intratumoral sub-populations: one more enriched in markers of terminal exhaustion (TEX-like) and the other with a bona fide resident phenotype (TRM-like). Treatment with anti-PD-1 and anti-CTLA-4 therapy resulted in expansion of these intratumoral populations, with the TRM-like subset displaying significantly enhanced cytotoxic capacity. TRM-like CD8+ T cells could also provide local immune protection against tumor rechallenge and a TRM gene signature extracted from tumor-free tissue was significantly associated with improved clinical outcomes in TNBC patients treated with checkpoint inhibitors.
- Published
- 2023