Emerging role of follicular regulatory T-cells in neuroimmunological disorders

Immune tolerance is essential for preventing self-damage while maintaining effective immune responses against foreign insults. Disruptions in this balance contribute to autoimmune and inflammatory conditions, including neuroimmunological disorders that are characterized by aberrant inflammation in the nervous system. Follicular regulatory T (T_FR) cells, a specialized subset of regulatory T (Treg) cells, play important roles in the control of humoral immunity, properly regulating high-affinity antibody responses to foreign antigens while limiting autoreactive antibody production. Beyond this well-documented role, recent studies have revealed its tissue-specific regulation along with the new discoveries of tissue Treg cells. In this review, we focus on the current understanding of T_FR cells and discuss the emerging findings of these cells in neuroimmunological disorders by highlighting their heterogeneity and plasticity in the regulation of disease progression.