Accumulation of peripheral autoreactive B cells in the absence of functional human regulatory T cells

作者：Kinnunen Tuure; Chamberlain Nicolas; Morbach Henner; Choi Jinyoung; Kim Sangtaek; Craft Joseph; Mayer Lloyd; Cancrini Caterina; Passerini Laura; Bacchetta Rosa; Ochs Hans D; Torgerson Troy R; Meffre Eric^*

来源：Blood, 2013, 121(9): 1595-1603.

DOI：10.1182/blood-2012-09-457465

Regulatory T cells (Tregs) play an essential role in preventing autoimmunity. Mutations in the forkhead box protein 3 (FOXP3) gene, which encodes a transcription factor critical for Treg function, result in a severe autoimmune disorder and the production of various autoantibodies in mice and in IPEX (immune dysregulation, polyendocrinopathy, enteropathy, X-linked) patients. However, it is unknown whether Tregs normally suppress autoreactive B cells. To investigate a role for Tregs in maintaining human B-cell tolerance, we tested the reactivity of recombinant antibodies isolated from single B cells isolated from IPEX patients. Characteristics and reactivity of antibodies expressed by new emigrant/transitional B cells from IPEX patients were similar to those from healthy donors, demonstrating that defective Treg function does not impact central B-cell tolerance. In contrast, mature naive B cells from IPEX patients often expressed autoreactive antibodies, suggesting an important role for Tregs in maintaining peripheral B-cell tolerance. T cells displayed an activated phenotype in IPEX patients, including their Treg-like cells, and showed up-regulation of CD40L, PD-1, and inducibl T-cell costimulator (ICOS), which may favor the accumulation of autoreactive mature naive B cells in these patients. Hence, our data demonstrate an essential role for Tregs in the establishment and the maintenance of peripheral B-cell tolerance in humans.

• 出版日期2013-2-28