Role of the Aryl Hydrocarbon Receptor in Controlling Maintenance and Functional Programs of RORγt+ Innate Lymphoid Cells and Intraepithelial Lymphocytes

Mucosal retinoic receptor-related orphan receptor (ROR)γt-expressing innate lymphoid cells (ILC) play an important role in the defense against intestinal pathogens and in promoting epithelial homeostasis and adaptation, thereby effectively protecting the vertebrate host against intestinal inflammatory disorders. The functional activity of RORγt+ ILC is under the control of environmental cues. However, the molecular sensors for such environmental signals are largely unknown. Recently, the aryl hydrocarbon receptor (AhR) has emerged as a master regulator for the postnatal maintenance of intestinal RORγt+ ILC and intraepithelial lymphocytes. AhR is a highly conserved transcription factor whose activity is regulated by environmental and dietary small molecule ligands. Here, we review the role of AhR signaling for the maintenance of intestinal immune cells and its impact on the immunological protection against intestinal infections and debilitating chronic inflammatory disorders

Targeting beta 1-integrin inhibits vascular leakage in endotoxemia

Loss of endothelial integrity promotes capillary leakage in numerous diseases, including sepsis, but there are no effective therapies for preserving endothelial barrier function. Angiopoietin-2 (ANGPT2) is a context-dependent regulator of vascular leakage that signals via both endothelial TEK receptor tyrosine kinase (TIE2) and integrins. Here, we show that antibodies against beta 1-integrin decrease LPS-induced vascular leakage in murine endotoxemia, as either a preventative or an intervention therapy. beta 1-integrin inhibiting antibodies bound to the vascular endotheliumin vivo improved the integrity of endothelial cell-cell junctions and protected mice from endotoxemia-associated cardiac failure, without affecting endothelial inflammation, serum proinflammatory cytokine levels, or TIE receptor signaling. Moreover, conditional deletion of a single allele of endothelial beta 1-integrin protected mice from LPS-induced vascular leakage. In endothelial mono-layers, the inflammatory agents thrombin, lipopolysaccharide (LPS), and IL-1 beta decreased junctional vascular endothelial (VE)-cadherin and induced actin stress fibers via beta 1- and alpha 5-integrins and ANGPT2. Additionally, beta 1-integrin inhibiting antibodies prevented inflammation-induced endothelial cell contractility and monolayer permeability. Mechanistically, the inflammatory agents stimulated ANGPT2-dependent translocation of alpha 5 beta 1-integrin into tensin-1-positive fibrillar adhesions, which destabilized the endothelial monolayer. Thus, beta 1-integrin promotes endothelial barrier disruption during inflammation, and targeting beta 1-integrin signaling could serve as a novel means of blocking pathological vascular leak.Peer reviewe

Development of an adenosquamous carcinoma histopathology - selective lung metastasis model

Peer reviewe

Receptor Tyrosine Kinase Signaling Networks Define Sensitivity to ERBB Inhibition and Stratify Kras Mutant Lung Cancers

Most non-small cell lung cancers (NSCLC) contain nontargetable mutations, including KRAS, TP53, or STK11/LKB1 alterations. By coupling ex viva drug sensitivity profiling with in vivo drug response studies, we aimed to identify drug vulnerabilities for these NSCLC subtypes. Primary adenosquamous carcinoma (ASC) or adenocarcinoma (AC) cultures were established from Kras(G12D/+);Lkb1(fl/fl) (KL) tumors or AC cultures from Kras(G12D/+);p53(fl/fl) (KP) tumors. Although p53-null cells readily propagated as conventional cultures, Lkb1-null cells required conditional reprograming for establishment. Drug response profiling revealed short-term response to MEK inhibition, yet long-term clonogenic assays demonstrated resistance, associated with sustained or adaptive activation of receptor tyrosine kinases (RTK): activation of ERBBs in KL cultures, or FGFR in AC niltures. Furthermore, pan-ERBB inhibition reduced the clonogenidty of KL cultures, which was exacerbated by combinatorial MEK inhibition, whereas combinatorial MEK and FGFR inhibition suppressed clonogenicity of AC cultures. Importantly, in vivo studies confirmed KL-selective sensitivity to pan-ERBB inhibition, which correlated with high ERBB ligand expression and activation of ERBB receptors, implying that ERBB network activity may serve as a predictive biomarker of drug response. Interestingly, in human NSCLCs, phosphorylation of EGFR or ERBB3 was frequently detected in ASCs and squamous cell carcinomas. We conclude that analysis of in situ ERBB signaling networks in conjunction with ex vivo drug response profiling and biochemical dissection of adaptive RTK activities may serve as a valid diagnostic approach to identify tumors sensitive to ERBB network inhibition.Peer reviewe

The origins and spread of domestic horses from the Western Eurasian steppes

This is the final version. Available on open access from Nature Research via the DOI in this recordData availability: All collapsed and paired-end sequence data for samples sequenced in this study are available in compressed fastq format through the European Nucleotide Archive under accession number PRJEB44430, together with rescaled and trimmed bam sequence alignments against both the nuclear and mitochondrial horse reference genomes. Previously published ancient data used in this study are available under accession numbers PRJEB7537, PRJEB10098, PRJEB10854, PRJEB22390 and PRJEB31613, and detailed in Supplementary Table 1. The genomes of ten modern horses, publicly available, were also accessed as indicated in their corresponding original publications57,61,85-87.NOTE: see the published version available via the DOI in this record for the full list of authorsDomestication of horses fundamentally transformed long-range mobility and warfare. However, modern domesticated breeds do not descend from the earliest domestic horse lineage associated with archaeological evidence of bridling, milking and corralling at Botai, Central Asia around 3500 BC. Other longstanding candidate regions for horse domestication, such as Iberia and Anatolia, have also recently been challenged. Thus, the genetic, geographic and temporal origins of modern domestic horses have remained unknown. Here we pinpoint the Western Eurasian steppes, especially the lower Volga-Don region, as the homeland of modern domestic horses. Furthermore, we map the population changes accompanying domestication from 273 ancient horse genomes. This reveals that modern domestic horses ultimately replaced almost all other local populations as they expanded rapidly across Eurasia from about 2000 BC, synchronously with equestrian material culture, including Sintashta spoke-wheeled chariots. We find that equestrianism involved strong selection for critical locomotor and behavioural adaptations at the GSDMC and ZFPM1 genes. Our results reject the commonly held association between horseback riding and the massive expansion of Yamnaya steppe pastoralists into Europe around 3000 BC driving the spread of Indo-European languages. This contrasts with the scenario in Asia where Indo-Iranian languages, chariots and horses spread together, following the early second millennium BC Sintashta culture

Natural aryl hydrocarbon receptor ligands control organogenesis of intestinal lymphoid follicles

Innate lymphoid cells (ILC) expressing the transcription factor ROR?t induce the postnatal formation of intestinal lymphoid follicles and regulate intestinal homeostasis. ROR?t(+) ILC express the aryl hydrocarbon receptor (AhR), a highly conserved, ligand-inducible transcription factor believed to control adaptation of multicellular organisms to environmental challenges. We show that AhR is required for the postnatal expansion of intestinal ROR?t(+) ILC and the formation of intestinal lymphoid follicles. AhR activity within ROR?t(+) ILC could be induced by dietary ligands such as those contained in vegetables of the family Brassicaceae. AhR-deficient mice were highly susceptible to infection with Citrobacter rodentium, a mouse model for attaching and effacing infections. Our results establish a molecular link between nutrients and the formation of immune system components required to maintain intestinal homeostasis and resistance to infections

Regulated expression of nuclear receptor RORγt confers distinct functional fates to NK cell receptor-expressing RORγt(+) innate lymphocytes

Whether the recently identified innate lymphocyte population coexpressing natural killer cell receptors (NKRs) and the nuclear receptor RORγt is part of the NK or lymphoid tissue inducer (LTi) cell lineage remains unclear. By using adoptive transfer of genetically tagged LTi-like cells, we demonstrate that NKR⁻RORγt(+) innate lymphocytes but not NK cells were direct progenitors to NKR(+)RORγt(+) cells in vivo. Genetic lineage tracing revealed that the differentiation of LTi-like cells was characterized by the stable upregulation of NKRs and a progressive loss of RORγt expression. Whereas interleukin-7 (IL-7) and intestinal microbiota stabilized RORγt expression within such NKR-LTi cells, IL-12 and IL-15 accelerated RORγt loss. RORγt(+) NKR-LTi cells produced IL-22, whereas RORγt⁻ NKR-LTi cells released IFN-γ and were potent inducers of colitis. Thus, the RORγt gradient in NKR-LTi cells serves as a tunable rheostat for their functional program. Our data also define a previously unappreciated role of RORγt⁻ NKR-LTi cells for the onset or maintenance of inflammatory bowel diseases

Regulated expression of nuclear receptor ROR t confers distinct functional fates to NK cell receptor-expressing ROR t(+) innate lymphocytes

Whether the recently identified innate lymphocyte population coexpressing natural killer cell receptors (NKRs) and the nuclear receptor ROR t is part of the NK or lymphoid tissue inducer (LTi) cell lineage remains unclear. By using adoptive transfer of genetically tagged LTi-like cells, we demonstrate that NKR ? ROR t(+) innate lymphocytes but not NK cells were direct progenitors to NKR(+)ROR t(+) cells in vivo. Genetic lineage tracing revealed that the differentiation of LTi-like cells was characterized by the stable upregulation of NKRs and a progressive loss of ROR t expression. Whereas interleukin-7 (IL-7) and intestinal microbiota stabilized ROR t expression within such NKR-LTi cells, IL-12 and IL-15 accelerated ROR t loss. ROR t(+) NKR-LTi cells produced IL-22, whereas ROR t ? NKR-LTi cells released IFN- and were potent inducers of colitis. Thus, the ROR t gradient in NKR-LTi cells serves as a tunable rheostat for their functional program. Our data also define a previously unappreciated role of ROR t ? NKR-LTi cells for the onset or maintenance of inflammatory bowel diseases