Abstract
In systemic lupus erythematosus (lupus), environmental effects acting within a permissive genetic background lead to autoimmune dysregulation. Dysfunction of CD4+ T cells contributes to pathology by providing help to autoreactive B and T cells, and CD4+ T cell dysfunction coincides with altered DNA methylation and histone modifications of select gene loci. However, chromatin accessibility states of distinct T cell subsets and mechanisms driving heterogeneous chromatin states across patients remain poorly understood. We defined the transcriptome and epigenome of multiple CD4+ T cell populations from patients with lupus and healthy individuals. Most patients with lupus, regardless of disease activity, had enhanced chromatin accessibility bearing hallmarks of inflammatory cytokine signals. Single-cell approaches revealed that chromatin changes extended to naive CD4+ T cells, uniformly affecting naive subpopulations. Transcriptional data and cellular and protein analyses suggested that the TNF family members, TNF-α, LIGHT, and TWEAK, were linked to observed molecular changes and the altered lupus chromatin state. However, we identified a patient subgroup prescribed angiotensin receptor blockers (ARBs), which lacked TNF-linked lupus chromatin accessibility features. These data raise questions about the role of lupus-associated chromatin changes in naive CD4+ T cell activation and differentiation and implicate ARBs in the regulation of disease-driven epigenetic states.
Authors
Andrew P. Hart, Jonathan J. Kotzin, Steffan W. Schulz, Jonathan S. Dunham, Alison L. Keenan, Joshua F. Baker, Andrew D. Wells, Daniel P. Beiting, Terri M. Laufer
Figure 2
The lupus epigenome is characterized by enhanced chromatin accessibility surrounding T cell activation and cytokine signaling genes.
