1636-Phenotype of Circulating Tumor-Reactive T Cells

The research article explores how identifying tumor-reactive T cells (TR-Ts) in peripheral blood can predict patient responses to immune checkpoint inhibitors (ICIs). By employing single-cell RNA and TCR sequencing, the researchers identified unique surface markers—CD49a, CD49b, and HLA-DR—that distinguish these rare circulating cells from other T cells. The study reveals that these circulating cells act as less-exhausted progenitors for the T cells found within tumors. Crucially, the researchers found that patients who respond well to treatment show a shift toward stem-like phenotypes and lower pre-treatment levels of the exhaustion marker CD38. These findings suggest that monitoring the phenotypic dynamics of circulating TR-Ts offers a minimally invasive way to forecast the success of immunotherapy in lung cancer patients.

References:

• Ito K, Iida K, Hirano T, et al. Phenotype of circulating tumor-reactive T cells predicts immune checkpoint inhibitor response in non-small cell lung cancer[J]. Nature Communications, 2026, 17(1): 2856.