Perivascular Tertiary Lymphoid Structures in Autoimmune Disease

Area of Science:

• Immunology
• Autoimmunity
• Inflammation Biology

Background:

• Autoimmune diseases remain incurable, characterized by chronic inflammation.
• Understanding the mechanisms of persistent autoimmune memory and lack of immune exhaustion is crucial.
• Decentralization of cellular immunity is increasingly recognized as a factor in chronic autoimmune responses.

Purpose of the Study:

• To review emerging data on how decentralized cellular immunity contributes to persistent autoimmune responses.
• To explore the role of tissue-resident memory T cells (TRM) and tertiary lymphoid structures (TLS) in autoimmune chronicity.
• To highlight the pathogenic role of TLS in autoimmune diseases and identify potential therapeutic targets.

Main Methods:

• Review of current scientific literature and emerging data.
• Analysis of mechanisms underlying immune memory and exhaustion in autoimmunity.
• Examination of the structure, composition, and function of tertiary lymphoid structures (TLS).

Main Results:

• Lasting immune memory is supported by tissue-resident memory T cells (TRM) and tertiary lymphoid structures (TLS).
• TLS, lymphoid aggregates outside of primary organs, form during chronic immune stimulation.
• Adventitial TLS in autoimmune vasculitis harbor TCF1hi CD4+ T stem cells, supplying continuous pathogenic effector T cells and promoting disease chronicity.

Conclusions:

• Decentralized immune responses, particularly TLS, play a critical role in the persistence and chronicity of autoimmune diseases.
• The local stemness and production of CD4+ T cells within TLS contribute to the resilience of autoreactive immunity.
• Targeting TLS and the stem-like T cells they contain presents a novel therapeutic strategy for managing autoimmune diseases.