Dynamic landscapes and protective immunity coordinated by influenza-specific lung-resident memory CD8 + T cells revealed by intravital imaging.

Lung-tissue-resident memory (T _RM ) CD8 ⁺ T cells are critical for heterosubtypic immunity against influenza virus (IAV) reinfection. How T _RM cells surveil the lung, respond to infection, and interact with other cells remains unresolved. Here, we used IAV infection of mice in combination with intravital and static imaging to define the spatiotemporal dynamics of lung T _RM cells before and after recall infection. CD69 ⁺ CD103 ⁺ T _RM cells preferentially localized to lung sites of prior IAV infection, where they exhibited patrolling behavior. After rechallenge, lung T _RM cells formed tight clusters in an antigen-dependent manner. Transcriptomic analysis of IAV-specific T _RM cells revealed the expression of several factors that regulate myeloid cell biology. In vivo rechallenge experiments demonstrated that protection elicited by T _RM cells is orchestrated in part by interferon (IFN)-γ-mediated recruitment of inflammatory monocytes into the lungs. Overall, these data illustrate the dynamic landscapes of CD103 ⁺ lung T _RM cells that mediate early protective immunity against IAV infection.
Competing Interests: Declaration of interests The authors declare no competing interests.
(Copyright © 2024 Elsevier Inc. All rights reserved.)