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Teslovich, N.

Publications and source records attributed to Teslovich, N..

3 recordsLinked to original sources

Rheumatoid arthritis heritability is concentrated in regulatory elements with CD4+ T cell-state-specific transcription factor binding profiles

Despite significant progress in annotating the genome with experimental methods, much of the regulatory noncoding genome remains poorly defined. Here we assert that regulatory elements may be characterized by leveraging local epigenomic signatures at sites where specific transcription factors (TFs) are bound. To link these two identifying features, we introduce IMPACT, a genome annotation strategy which identifies regulatory elements defined by cell-state-specific TF binding profiles, learned from 515 chromatin and sequence annotations. We validate IMPACT using multiple compelling applications. First, IMPACT predicts TF motif binding with high accuracy (average AUC 0.92, s.e. 0.03; across 8 TFs), a significant improvement (all p<6.9e-15) over intersecting motifs with open chromatin (average AUC 0.66, s.e. 0.11). Second, an IMPACT annotation trained on RNA polymerase II is more enriched for peripheral blood cis-eQTL variation (N=3,754) than sequence based annotations, such as promoters and regions around the TSS, (permutation p<1e-3, 25% average increase in enrichment). Third, integration with rheumatoid arthritis (RA) summary statistics from European (N=38,242) and East Asian (N=22,515) populations revealed that the top 5% of CD4+ Treg IMPACT regulatory elements capture 85.7% (s.e. 19.4%) of RA h2 (p<1.6e-5) and that the top 9.8% of Treg IMPACT regulatory elements, consisting of all SNPs with a non-zero annotation value, capture 97.3% (s.e. 18.2%) of RA h2 (p<7.6e-7), the most comprehensive explanation for RA h2 to date. In comparison, the average RA h2 captured by compared CD4+ T histone marks is 42.3% and by CD4+ T specifically expressed gene sets is 36.4%. Finally, integration with RA fine-mapping data (N=27,345) revealed a significant enrichment (2.87, p<8.6e-3) of putatively causal variants across 20 RA associated loci in the top 1% of CD4+ Treg IMPACT regulatory regions. Overall, we find that IMPACT generalizes well to other cell types in identifying complex trait associated regulatory elements.

genetics

A genome-wide innateness gradient defines the functional state of human innate T cells

Innate T cells (ITCs), including invariant natural killer T (iNKT) cells, mucosal-associated invariant T (MAIT) cells, and {gamma}{delta} T cell populations, use conserved antigen receptors generated by somatic recombination to respond to non-peptide antigens in an innate-like manner. Understanding where these cells fit in the scheme of immunity has been a puzzle since their discovery. Here, immunophenotyping of 101 individuals revealed that these populations account for as much as 25% of peripheral human T cells. To better understand these cells, we generated detailed gene expression profiles using low-input RNA-seq and confirmed key findings through protein-level and functional validation. Unbiased transcriptomic analyses revealed a continuous innateness gradient with adaptive T cells at one end followed by MAIT, iNKT, V{delta}1+ T, V{delta}2+ T, and natural killer cells at the other end. Innateness was characterized by decreased expression of translational machinery genes and reduced proliferative potential, which allowed for prioritization of effector functions, including rapid cytokine and chemokine production, and cytotoxicity. Thus, global transcriptional programs uncovered rapid proliferation and rapid effector functions as competing goals that respectively define adaptive and innate states.\n\nOne Sentence SummaryAdaptive and innate T cells align along a continuous innateness gradient, reflecting a trade-off between effector function and proliferative capacity.

immunology

Fine-mapping identifies causal variants for RA and T1D in DNASE1L3, SIRPG, MEG3, TNFAIP3 and CD28/CTLA4 loci

We fine-mapped 76 rheumatoid arthritis (RA) and type 1 diabetes (T1D) loci outside of the MHC. After sequencing 799 1kb regulatory (H3K4me3) regions within these loci in 568 individuals, we observed accurate imputation for 89% of common variants. We fine-mapped1,2 these loci in RA (11,475 cases, 15,870 controls)3, T1D (9,334 cases and 11,111 controls) 4 and combined datasets. We reduced the number of potential causal variants to [&le;]5 in 8 RA and 11 T1D loci. We identified causal missense variants in five loci (DNASE1L3, SIRPG, PTPN22, SH2B3 and TYK2) and likely causal non-coding variants in six loci (MEG3, TNFAIP3, CD28/CTLA4, ANKRD55, IL2RA, REL/PUS10). Functional analysis confirmed allele specific binding and differential enhancer activity for three variants: the CD28/CTLA4 rs117701653 SNP, the TNFAIP3 rs35926684 indel, and the MEG3 rs34552516 indel. This study demonstrates the potential for dense genotyping and imputation to pinpoint missense and non-coding causal alleles.

genetics