Distinct Gene Regulatory Pathways for Human Innate Versus Adaptive Lymphoid Cells [ChIP-seq & ATAC-seq]

Innate lymphoid cells (ILCs) serve as sentinels in mucosal tissues, sensing release of soluble inflammatory mediators, rapidly communicating danger via cytokine secretion, and functioning as guardians of tissue homeostasis. Although ILCs have been studied extensively in model organisms, little is known about these “first responders” in humans, especially their lineage and functional kinships to cytokine-secreting T helper cell (Th) counterparts. Here, we report gene regulatory circuitries for four human ILC–Th counterparts derived from mucosal environments, revealing that each ILC subset diverges as a distinct lineage from Th and circulating natural killer cells, but shares circuitry devoted to functional polarization with their Th counterparts. Super-enhancers demarcate cohorts of cell identity genes in each lineage, uncovering new modes of regulation for signature cytokines, novel molecules that likely impart important functions to ILCs, and potential mechanisms for autoimmune disease SNP associations within ILC–Th subsets. Overall design: Molecular profiling of innate lymphoid and T helper cells subsets purified from tonsils and NK cells purified from peripheral blood using Assay for Transposase-Accessible Chromatin (ATAC) and chromatin immunoprecipitation (H3K4me3 and H3K27ac).