Protein phosphatase 2A propels follicular T helper cell development in lupus
Document Type
Journal Article
Publication Date
4-1-2023
Journal
Journal of autoimmunity
Volume
136
DOI
10.1016/j.jaut.2023.103028
Keywords
PP2A; SLE; Tfh; mTOR
Abstract
Follicular helper T (Tfh) cells are important for generating humoral immune responses by helping B cells form germinal centers (GCs) and the production of high-affinity antibodies. However, aberrant Tfh cell expansion also contributes to the generation of self-reactive autoantibodies and promotes autoantibody-mediated autoimmune diseases such as systemic lupus erythematosus (SLE). Protein phosphatase 2A catalytic subunit alpha isoform (PP2A Cα) expression levels are elevated in peripheral T cells of SLE patients and positively correlate with autoantibody titers and disease activity. Here, we demonstrate a critical role of PP2A in Tfh differentiation by using T cell restricted PP2A Cα deficient mice. We observed impaired Tfh differentiation and GC response in two different classical Tfh induction models. Mechanistic studies revealed that downregulation of protein translation of the Tfh lineage transcription factor BCL6 in PP2A deficient T cells. Importantly, we found that PP2A deficiency by either gene knockout or chemical inhibition alleviated lupus severity in mice. Lastly, we confirmed a positive correlation between PP2A Cα and BCL6 protein levels in human CD4 T cells from patients with SLE. In summary, our study revealed a critical role of PP2A in regulating Tfh cells and suggests it is a potential therapeutic target for lupus.
APA Citation
Jiang, Yu; Jin, Xuexiao; Chi, Zhexu; Bai, Yadan; Manthiram, Kalpana; Mudd, Pamela; Zhu, Kaixiang; Wang, Lie; Schwartzberg, Pamela L.; Han, Yongmei; Gao, Xiang; Lu, Linrong; and Xu, Qin, "Protein phosphatase 2A propels follicular T helper cell development in lupus" (2023). GW Authored Works. Paper 2512.
https://hsrc.himmelfarb.gwu.edu/gwhpubs/2512
Department
Surgery