IMMUNOLOGY2025™ Conference Recordings-PD-1 and T cell specification

PD-1 and T cell specification - Niroshana Anandasbapathy

Video Transcription

Video Summary

The speaker described how tissue immunity is organized and how tumor-infiltrating T cells (TILs) relate to immune responses in infection, vaccination, and cancer. In a large systems analysis of melanoma and other solid tumors, they found that TILs associated with poor anti-PD-1 response looked more like early activation states, while TILs associated with good response resembled long-lived memory and resident memory programs, along with interferon-gamma response and dendritic cell maturation. These signatures predicted melanoma survival and checkpoint response better than single markers. In the second part, unpublished mouse and human data showed that PD-1 is not just an exhaustion marker: it helps CD8 T cells become tissue-resident memory cells by promoting early tissue programming, TGF-beta signaling, and skin engraftment. Blocking PD-1 early reduced resident memory formation and could help explain checkpoint toxicities in skin and lung.

Keywords

tumor-infiltrating T cells

PD-1 checkpoint response

resident memory T cells

melanoma survival

interferon-gamma signaling

TGF-beta tissue programming