Biology subjects

Wabnitz, G.

Publications and source records attributed to Wabnitz, G..

3 recordsLinked to original sources

bioRxiv2022

Human and murine neutrophils share core transcriptional programs in both homeostatic and inflamed contexts

Neutrophils are frequently studied in murine models, but the extent to which findings translate to humans remains poorly defined. Here, we performed an integrative transcriptomic analysis of 11 murine and 13 human datasets. In homeostasis, neutrophils exhibited the highest number of lineage-specific genes and the greatest degree of correlated expression among genes with one-to-one orthologs (r = 0.79, P < 2.2 x 10-16) compared to other leukocytes. In inflammation, neutrophils displayed considerable transcriptional diversity, but shared a core inflammation program across a broad range of conditions which was conserved between species. This core program included genes encoding IL-1 family members, CD14, IL-4R, CD69 and PD-L1. Chromatin accessibility of core inflammation genes increased significantly in blood compared to bone marrow and further with migration from blood to tissue. Transcription factor enrichment analysis nominated members of the NF-{kappa}B family and AP-1 complex as important drivers of the core inflammation program, and HoxB8 neutrophils with JUNB knockout showed a significantly reduced expression of core inflammation genes at baseline and upon stimulation. In vitro perturbations confirmed surface protein upregulation of core inflammation members in both species. Together, we demonstrate substantial transcriptional conservation in neutrophils in homeostasis and identify a core inflammation program conserved across species. This systems biology approach can be leveraged to improve transitions between the murine and human context. Key PointsO_LIThe transcriptome of resting neutrophils is substantially conserved between humans and mice C_LIO_LIA core inflammation program in neutrophils is shared across a broad range of conditions and conserved across humans and mice C_LI Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=52 SRC="FIGDIR/small/516246v1_ufig1.gif" ALT="Figure 1"> View larger version (17K): org.highwire.dtl.DTLVardef@1f6b40borg.highwire.dtl.DTLVardef@1a67bb4org.highwire.dtl.DTLVardef@1039a8forg.highwire.dtl.DTLVardef@1982d10_HPS_FORMAT_FIGEXP M_FIG C_FIG

immunology↗

bioRxiv2021

Aging and interferon gamma response drive the phenotype of neutrophils in the inflamed joint

ObjectivesNeutrophils are typically the most abundant leukocyte in arthritic synovial fluid. We sought to understand changes that occur in neutrophils as they migrate from blood to joint. MethodsWe performed RNA sequencing of neutrophils from healthy human blood, arthritic blood, and arthritic synovial fluid, comparing transcriptional signatures with those from murine K/BxN serum transfer arthritis. We employed mass cytometry to quantify protein expression and sought to reproduce the synovial fluid phenotype ex vivo in cultured healthy blood neutrophils. ResultsBlood neutrophils from healthy donors and patients with active arthritis exhibited largely similar transcriptional signatures. By contrast, synovial fluid neutrophils exhibited more than 1,600 differentially expressed genes. Gene signatures identified a prominent response to interferon gamma (IFN{gamma}), as well as to tumor necrosis factor, interleukin 6, and hypoxia, in both humans and mice. Mass cytometry also found healthy and arthritic donor blood neutrophils largely indistinguishable but revealed a range of neutrophil phenotypes in synovial fluid defined by downregulation of CXCR1 and upregulation of Fc{gamma}RI, HLA-DR, PD-L1, ICAM-1 and CXCR4. Reproduction of key elements of this signature in cultured blood neutrophils required both IFN{gamma} and prolonged culture. ConclusionsCirculating neutrophils from arthritis patients resemble those from healthy controls, but joint fluid cells exhibit a network of changes, conserved across species, that implicate IFN{gamma} response and aging as complementary drivers of the synovial neutrophil phenotype. KEY MESSAGESO_ST_ABSWhat is already known about this subject?C_ST_ABSO_LINeutrophils are central in the effector phase of inflammatory arthritis but their phenotypic heterogeneity in inflamed synovial fluid is poorly understood. C_LI What does this study add?O_LIRNA-seq and mass cytometry identify a hallmark phenotype of neutrophils in synovial fluid consisting of upregulated ICAM-1, HLA-DR, PD-L1, Fc receptors and CXCR4. C_LIO_LITranscriptomics highlight an IFN{gamma} response signature conserved across humans and mice. C_LIO_LIIn vitro experiments implicate aging and IFN{gamma} as complementary factors orchestrating the synovial fluid neutrophil phenotype. C_LI How might this impact on clinical practice or future developments?O_LIUnderstanding the specific features of neutrophils in the arthritic joint may disclose opportunities for safe therapeutic targeting of this lineage. C_LI

immunology↗

bioRxiv2021

Inflammation induces pro-NETotic neutrophils via TNFR2 signaling

Cytokines released during chronic inflammatory diseases induce pro-inflammatory properties in polymorphonuclear neutrophils (PMN). Here we show that in vitro cytokine treatment leads to the development of a subgroup of human PMN expressing CCR5, termed CCR5+ cytokine-induced PMN (CCR5+ cPMN). Auto/paracrine TNF signaling increases intracellular neutrophil elastase (ELANE) abundance and induces NETosis in CCR5+ cPMN. Triggering of CCR5 amplifies NETosis. Membranous TNF (mTNF) outside-in signaling induces the formation of reactive oxygen species, a known activator of NETosis. In vivo, we find an increased number of CCR5+ cPMN in the peripheral blood and inflamed lamina propria of patients with ulcerative colitis (UC) but not Crohns disease (CD). Notably, failure of anti-TNF therapy is associated with higher frequencies of CCR5+ cPMN. In conclusion, we identify a phenotype of pro-NETotic, CCR5 positive PMN present in inflamed tissue in vivo and inducible in vitro. These cells may reflect an important component of tissue damage during chronic inflammation and could be of diagnostic value.

immunology↗