Precocious Interleukin 21 Expression in Naive Mice Identifies a Natural Helper Cell Population in Autoimmune Disease.

ABSTRACT: Interleukin 21 (IL-21) plays key roles in humoral immunity and autoimmune diseases. It is known to function in mature CD4⁺ T follicular B cell helper (T_FH) cells, but its potential involvement in early T cell ontogeny is unclear. Here, we find that a significant population of newly activated thymic and peripheral CD4⁺ T cells functionally expresses IL-21 soon after birth. This naturally occurring population, termed natural (n)T_H21 cells, exhibits considerable similarity to mature T_FH cells. nT_H21 cells originating and activated in the thymus are strictly dependent on autoimmune regulator (AIRE) and express high levels of NUR77, consistent with a bias toward self-reactivity. Their activation/expansion in the periphery require

SUBMITTER: Marnik EA 

PROVIDER: S-EPMC5661890 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature