The Role of Tissue Resident Memory Cells in Immunodermatological Disorders

Area of Science:

• Immunology
• Dermatology

Background:

• Tissue-resident memory T cells (TRMs) are crucial for localized immune memory in tissues.
• In chronic inflammatory skin diseases such as psoriasis, atopic dermatitis, and vitiligo, TRMs contribute to disease persistence and recurrence at specific sites.

Purpose of the Study:

• To review current understanding of TRMs in chronic inflammatory skin diseases.
• To discuss the clinical and translational implications of TRMs, including potential targeted therapies.

Main Methods:

• Literature review of original human, animal, or in vitro studies.
• Focus on TRMs in the pathogenesis and persistence of dermatologic diseases.

Main Results:

• CD8+ TRMs persist in healed psoriatic skin.
• Both CD4+ and CD8+ TRMs maintain Th2/Th22 inflammation in atopic dermatitis.
• Autoreactive CD8+ TRMs cause melanocyte destruction in vitiligo.
• TRMs exhibit persistence, reactivation by triggers, and resistance to therapies, explaining chronic skin disease recurrence.

Conclusions:

• TRMs provide a unifying framework for understanding chronic, relapsing inflammatory skin diseases.
• Disease-specific TRM pathways exist, influenced by immune polarization and antigen specificity.
• Targeting TRMs is a promising therapeutic approach and TRMs can serve as biomarkers for disease activity.