Skin-resident memory CD8 ⁺ T cells trigger a state of tissue-wide pathogen alert

TLDR

Resident memory T cells are long‑lived, tissue‑resident cells that provide rapid immune memory at sites of prior infection. They secrete inflammatory proteins that activate local immune cells, enabling protection even against unrelated pathogens. CD8⁺ T_RM act as first responders in skin and female reproductive tissues upon antigen reencounter, while CD4⁺ T_RM protect mice from reinfection with intravaginal HSV‑2. Schenkel et al.

Abstract

Resident memory T cells sound the alarm Immunological memory protects against reinfection. Resident memory T cells (T RM ) are long-lived and remain in the tissues where they first encountered a pathogen (see the Perspective by Carbone and Gebhardt). Schenkel et al. and Ariotti et al. found that CD8 + T RM cells act like first responders in the female reproductive tissue or the skin of mice upon antigen reencounter. By secreting inflammatory proteins, T RM cells rapidly activated local immune cells to respond, so much so that they protected against infection with an unrelated pathogen. Iijima and Iwasaki found that CD4 + T RM cells protected mice against reinfection with intravaginal herpes simplex virus 2. Science , this issue p. 98 , p. 101 , p. 93 ; see also p. 40