Tissue-Resident Memory T Cells: Sheltering-in-Place for Host Defense

Area of Science:

• Immunology
• Cellular Biology
• Vaccinology

Background:

• The traditional view of memory T cells (TcircM) defending tissues is being replaced by a new paradigm.
• Tissue-resident memory T cells (TRM) are now recognized as crucial sentinels in diverse tissues.

Purpose of the Study:

• To review the characteristics and functions of TRM cells.
• To highlight the role of TRM in host defense, autoimmunity, and allergy.
• To discuss the implications of TRM for vaccine design and therapeutic strategies.

Main Methods:

• Review of existing literature on T cell-mediated immunity, focusing on TRM.
• Analysis of animal models and human studies investigating TRM in infection, autoimmunity, and allergy.
• Discussion of current and emerging TRM-centered therapeutic and vaccine strategies.

Main Results:

• TRM cells are stably positioned in peripheral tissues, providing rapid, tissue-autonomous defense against reinfections.
• TRM play a significant role in both protection against recurring infections and in the pathogenesis of autoimmunity and allergies.
• TRM-targeted vaccines and therapies show promise in animal models, outperforming traditional approaches.

Conclusions:

• TRM represent a critical component of adaptive immunity, offering a first line of defense at the tissue level.
• Harnessing TRM through targeted activation or inactivation is a promising strategy for developing novel vaccines and therapies.
• Future research and development should prioritize TRM-driven approaches for infectious diseases, cancer, autoimmunity, and allergies.