Dissection and Function of Autoimmunity-associated TNFAIP3 (A20) Gene Enhancers in Humanized Mouse Models [ChIP-seq]

Enhancers affect gene expression and disease. Little is known about enhancers that regulate human disease-associated genes in their native chromosomal context in primary cells relevant for pathogenesis. We used a BAC transgenic approach combined with CRISPR- and recombineering-mediated genome editing to dissect enhancers that regulate human TNFAIP3/A20, which is tightly linked with autoimmune diseases, in vivo and in primary immune cells. >20 enhancers in the A20 superenhancer were redundant; A20 expression was regulated by a topologically associating subdomain (sub-TAD) that harbors 5 enhancers. Deletion of this sub- TAD enhanced inflammatory responses and autoantibody production, establishing its functional importance in vivo. We identified cell- and activation-specific enhancers within this sub-TAD, including a key role for an enhancer harboring a proposed causal SLE-associated SNV. These findings map genomic regions that regulate human A20 expression to prevent inflammatory pathology and autoimmunity, and provide a platform for causally linking enhancers and SNVs with disease phenotypes. Analysis of epigenomic changes in human macrophages stimulated with LPS