Ezh2-mediated epigenetic modification is required for allogeneic T cell-induced lupus disease
- PDF / 1,383,630 Bytes
- 10 Pages / 595.276 x 790.866 pts Page_size
- 13 Downloads / 196 Views
RESEARCH ARTICLE
Open Access
Ezh2-mediated epigenetic modification is required for allogeneic T cell-induced lupus disease Yuxuan Zhen1, Roger D. Smith2, Fred D. Finkelman1,3 and Wen-Hai Shao1*
Abstract Background: The mechanisms involved in the pathogenesis of autoimmune disorders, including systemic lupus erythematosus (SLE), have not been fully elucidated. Some of these mechanisms involve epigenetic regulation of gene expression. The histone methyltransferase Ezh2 contributes to epigenetic regulation of gene expression, is highly expressed in germinal center (GC) B cells and follicular T helper (TFH) cells, and may be involved in lupus pathogenesis. Methods: The murine bm12 model of lupus-like chronic graft versus host disease (cGVHD) was induced by intraperitoneal injection of negatively isolated allogeneic CD4+ T cells. Lupus-like disease development was monitored by ELISA determination of serum anti-dsDNA and anti-chromatin antibody titers. Immune cell activation and Ezh2 expression were evaluated by flow cytometry and Western blotting. Results: Decreased autoantibody production and GC formation are observed when Ezh2-deficient CD4+ T cells are used instead of wild-type (WT) to induce cGVHD and when mice that receive allogeneic WT donor T cells to induce cGVHD are treated with GSK503, an Ezh2-specific inhibitor. In the bm12 cGVHD model, WT donor T cells are normally fully activated 1 week after infusion into an allogeneic host, exhibit a TFH cell (PD-1hi/CXCR5hi) phenotype with upregulated Ezh2, and activate B cells to form germinal centers (GCs). In contrast, Ezh2-deficient donor T cells generate fewer TFH cells that fail to activate B cells or promote GC formation. Despite similar T-independent, LPS-induced B cell responses, OVA-immunized CD4.Ezh2-KO mice had a skewed low-affinity IgM phenotype in comparison to similarly treated WT mice. In addition, early after OVA immunization, more CD4+ T cells from B6.CD4.Ezh2-KO mice had a CD44lo/CD62Llo phenotype, which suggests arrested or delayed activation, than CD4+ T cells from ovalbuminimmunized B6.WT mice. Conclusion: Ezh2 gene deletion or pharmacological Ezh2 inhibition suppresses autoantibody production and GC formation in bm12 lupus-like cGVHD and decreases affinity maturation and isotype switching in response to immunization with a T cell-dependent antigen. Ezh2 inhibition may be useful for the treatment of lupus and other autoimmune disorders. Keywords: SLE, cGVHD, Ezh2, H3Kme, GSK503, GC B cells, TFH cells, OVA-immunization
* Correspondence: [email protected] 1 Division of Immunology, Allergy and Rheumatology, Department of Internal Medicine, University of Cincinnati, Cincinnati, OH 45267, USA Full list of author information is available at the end of the article © The Author(s). 2020 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the
Data Loading...
