技术资料

Crohn’s disease (CD) is a complex chronic inflammatory disorder with both gastrointestinal and extra-intestinal manifestations associated immune dysregulation. Analyzing 202,359 cells from 170 specimens across 83 patients,we identify a distinct epithelial cell type in both terminal ileum and ascending colon (hereon as ‘LND’) with high expression of LCN2,NOS2,and DUOX2 and genes related to antimicrobial response and immunoregulation. LND cells,confirmed by in-situ RNA and protein imaging,are rare in non-IBD controls but expand in active CD,and actively interact with immune cells and specifically express IBD/CD susceptibility genes,suggesting a possible function in CD immunopathogenesis. Furthermore,we discover early and late LND subpopulations with different origins and developmental potential. A higher ratio of late-to-early LND cells correlates with better response to anti-TNF treatment. Our findings thus suggest a potential pathogenic role for LND cells in both Crohn’s ileitis and colitis. Crohn’s disease (CD) is a complex disease associated with immune dysregulation. Here the authors use multimodal data to identify and characterize an epithelial cell population,termed ‘LND’ cells,in both terminal ileum and ascending colon,with LND interacting locally with immune cells and potentially contributing to CD pathology. View Publication

Platelets are key mediators of atherothrombosis,yet,limited tools exist to identify individuals with a hyperreactive platelet phenotype. In this study,we investigate the association of platelet hyperreactivity and cardiovascular events,and introduce a tool,the Platelet Reactivity ExpreSsion Score (PRESS),which integrates platelet aggregation responses and RNA sequencing. Among patients with peripheral artery disease (PAD),those with a hyperreactive platelet response (>60% aggregation) to 0.4 µM epinephrine had a higher incidence of the 30 day primary cardiovascular endpoint (37.2% vs. 15.3% in those without hyperreactivity,adjusted HR 2.76,95% CI 1.5–5.1,p = 0.002). PRESS performs well in identifying a hyperreactive phenotype in patients with PAD (AUC [cross-validation] 0.81,95% CI 0.68 –0.94,n = 84) and in an independent cohort of healthy participants (AUC [validation] 0.77,95% CI 0.75 –0.79,n = 35). Following multivariable adjustment,PAD individuals with a PRESS score above the median are at higher risk for a future cardiovascular event (adjusted HR 1.90,CI 1.07–3.36; p = 0.027,n = 129,NCT02106429). This study derives and validates the ability of PRESS to discriminate platelet hyperreactivity and identify those at increased cardiovascular risk. Future studies in a larger independent cohort are warranted for further validation. The development of a platelet reactivity expression score opens the possibility for a personalized approach to antithrombotic therapy for cardiovascular risk reduction. Platelet hyperreactivity is associated with cardiovascular events in patients with PAD. Here the authors derive and validate a circulating platelet genetic signature to discriminate platelet hyperreactivity and cardiovascular risk. View Publication

Visceral white adipose tissues (WAT) regulate systemic lipid metabolism and inflammation. Dysfunctional WAT drive chronic inflammation and facilitate atherosclerosis. Adipose tissue-associated macrophages (ATM) are the predominant immune cells in WAT,but their heterogeneity and phenotypes are poorly defined during atherogenesis. The scavenger receptor CD36 mediates ATM crosstalk with other adipose tissue cells,driving chronic inflammation. Here,we combined the single-cell RNA sequencing technique with cell metabolic and functional assays on major WAT ATM subpopulations using a diet-induced atherosclerosis mouse model (Apoe-null). We also examined the role of CD36 using Apoe/Cd36 double-null mice. Based on transcriptomics data and differential gene expression analysis,we identified a previously undefined group of ATM displaying low viability and high lipid metabolism and labeled them as “unhealthy macrophages”. Their phenotypes suggest a subpopulation of ATM under lipid stress. We also identified lipid-associated macrophages (LAM),which were previously described in obesity. Interestingly,LAM increased 8.4-fold in Apoe/Cd36 double-null mice on an atherogenic diet,but not in Apoe-null mice. The increase in LAM was accompanied by more ATM lipid uptake,reduced adipocyte hypertrophy,and less inflammation. In conclusion,CD36 mediates a delicate balance between lipid metabolism and inflammation in visceral adipose tissues. Under atherogenic conditions,CD36 deficiency reduces inflammation and increases lipid metabolism in WAT by promoting LAM accumulation. View Publication

Recurrent infections are a hallmark of STAT3 DN hyper-IgE syndrome,a rare immunodeficiency syndrome,and our study suggests that neutrophil-avid nanocarriers have potential for directed delivery of cargo therapeutics to improve neutrophil infection clearance in these patients. Recurrent infections are a hallmark of STAT3 dominant-negative hyper-IgE syndrome (STAT3 HIES),a rare immunodeficiency syndrome previously known as Jobs syndrome,along with elevated IgE levels and impaired neutrophil function. We have been developing nanoparticles with neutrophil trophism that home to the sites of infection via these first-responder leukocytes,named neutrophil-avid nanocarriers (NANs). Here,we demonstrate that human neutrophils can phagocytose nanogels (NGs),a type of NAN,with enhanced uptake after particle serum opsonization,comparing neutrophils from healthy individuals to those with STAT3 HIES,where both groups exhibit NG uptake; however,the patient group showed reduced phagocytosis efficiency with serum-opsonized NANs. Proteomic analysis of NG protein corona revealed complement components,particularly C3,as predominant in both groups. Difference between groups includes STAT3 HIES samples with higher neutrophil protein and lower acute-phase protein expression. The study suggests that despite neutrophil dysfunction in STAT3 HIES,NANs have potential for directed delivery of cargo therapeutics to improve neutrophil infection clearance. View Publication

SummaryTumor-infiltrating regulatory T cells (TI-Tregs) elicit immunosuppressive effects in the tumor microenvironment (TME) leading to accelerated tumor growth and resistance to immunotherapies against solid tumors. Here,we demonstrate that poly-(ADP-ribose)-polymerase-11 (PARP11) is an essential regulator of immunosuppressive activities of TI-Tregs. Expression of PARP11 correlates with TI-Treg cell numbers and poor responses to immune checkpoint blockade (ICB) in human patients with cancer. Tumor-derived factors including adenosine and prostaglandin E2 induce PARP11 in TI-Tregs. Knockout of PARP11 in the cells of the TME or treatment of tumor-bearing mice with selective PARP11 inhibitor ITK7 inactivates TI-Tregs and reinvigorates anti-tumor immune responses. Accordingly,ITK7 decelerates tumor growth and significantly increases the efficacy of anti-tumor immunotherapies including ICB and adoptive transfer of chimeric antigen receptor (CAR) T cells. These results characterize PARP11 as a key driver of TI-Treg activities and a major regulator of immunosuppressive TME and argue for targeting PARP11 to augment anti-cancer immunotherapies. Graphical abstract Highlights•Tumor-derived factors upregulate PARP11 in the tumor-infiltrating Treg cells•PARP11 supports the immunosuppressive properties of Treg cells•Pharmacologic inhibition of PARP11 inactivates intratumoral Treg cells•PARP11 inhibitor augments the efficacy of immunotherapies Basavaraja et al. demonstrate that induction of PARP11 in the intratumoral regulatory T (Treg) cells is required for their regulatory functions and contributes to the immunosuppressive tumor microenvironment. The selective inhibitor of PARP11 ITK7 inactivates tumor Treg cells and improves the efficacy of immunotherapies against tumors. View Publication

IntroductionInnate lymphoid cells (ILCs) are enriched at mucosal surfaces where they respond rapidly to environmental stimuli and contribute to both tissue inflammation and healing. MethodsTo gain insight into the role of ILCs in the pathology and recovery from COVID-19 infection,we employed a multi-omics approach consisting of Abseq and targeted mRNA sequencing to respectively probe the surface marker expression,transcriptional profile and heterogeneity of ILCs in peripheral blood of patients with COVID-19 compared with healthy controls. ResultsWe found that the frequency of ILC1 and ILC2 cells was significantly increased in COVID-19 patients. Moreover,all ILC subsets displayed a significantly higher frequency of CD69-expressing cells,indicating a heightened state of activation. ILC2s from COVID-19 patients had the highest number of significantly differentially expressed (DE) genes. The most notable genes DE in COVID-19 vs healthy participants included a) genes associated with responses to virus infections and b) genes that support ILC self-proliferation,activation and homeostasis. In addition,differential gene regulatory network analysis revealed ILC-specific regulons and their interactions driving the differential gene expression in each ILC. DiscussionOverall,this study provides mechanistic insights into the characteristics of ILC subsets activated during COVID-19 infection. View Publication

Recently developed small-molecule inhibitors of the lysosomal protease dipeptidyl peptidase 1 (DPP1),also known as cathepsin C (CatC),can suppress suppurative inflammation in vivo by blocking the processing of zymogenic (pro-) forms of neutrophil serine proteases (NSPs),including neutrophil elastase,proteinase 3,and cathepsin G. DPP1 also plays an important role in activating granzyme serine proteases that are expressed by cytotoxic T lymphocytes (CTL) and natural killer (NK) cells. Therefore,it is critical to determine whether DPP1 inhibition can also cause off-target suppression of CTL/NK-cell-mediated killing of virus-infected or malignant cells. Herein,we demonstrate that the processing of human granzymes A and B,transitioning from zymogen to active proteases,is not solely dependent on DPP1. Thus,the killing of target cells by primary human CD8+ T cells,NK cells,and gene-engineered anti-CD19 CAR T cells was not blocked in vitro even after prior exposure to high concentrations of the reversible DPP1 inhibitor brensocatib. Consistent with this observation,the turnover of model granzyme A/B peptide substrates in the human CTL/NK cell lysates was not significantly reduced by brensocatib. In contrast,preincubation with brensocatib almost entirely abolished (>90%) both the cytotoxic activity of mouse CD8+ T cells and granzyme substrate turnover. Overall,our finding that the effects of DPP1 inhibition on human cytotoxic lymphocytes are attenuated in comparison to those of mice indicates that granzyme processing/activation pathways differ between mice and humans. Moreover,the in vitro data suggest that human subjects treated with reversible DPP1 inhibitors,such as brensocatib,are unlikely to experience any appreciable deficits in CTL/NK-cell-mediated immunities. View Publication

Migrasomes are organelles that are generated by migrating cells. Here we report the key role of neutrophil-derived migrasomes in haemostasis. We found that a large number of neutrophil-derived migrasomes exist in the blood of mice and humans. Compared with neutrophil cell bodies and platelets,these migrasomes adsorb and enrich coagulation factors on the surface. Moreover,they are highly enriched with adhesion molecules,which enable them to preferentially accumulate at sites of injury,where they trigger platelet activation and clot formation. Depletion of neutrophils,or genetic reduction of the number of these migrasomes,significantly decreases platelet plug formation and impairs coagulation. These defects can be rescued by intravenous injection of purified neutrophil-derived migrasomes. Our study reveals neutrophil-derived migrasomes as a previously unrecognized essential component of the haemostasis system,which may shed light on the cause of various coagulation disorders and open therapeutic possibilities. Jiang et al. document an abundance of neutrophil-derived migrasomes in the blood of mice and humans and show that migrasomes are enriched in coagulation factors,accumulate at sites of injury and trigger platelet activation and clot formation. View Publication

SummarySepsis survivors are at high risk for infection-related rehospitalization and mortality for years following the resolution of the acute septic event. These infection-causing microorganisms generally do not cause disease in immunocompetent hosts,suggesting that the post-septic immune response is compromised. Given the importance of CD4 T cells in the development of long-lasting protective immunity,we analyzed their post-septic function. Here we showed that sepsis induced chronic increased and non-specific production of IL-17 by CD4 T cells,resulting in the inability to mount an effective immune response to a secondary pneumonia challenge. Altered cell function was associated with metabolic reprogramming,characterized by mitochondrial dysfunction and increased glycolysis. This metabolic reprogramming began during the acute septic event and persisted long after sepsis had resolved. Our findings reveal cell metabolism as a potential therapeutic target. Given the critical role of cell metabolism in the physiological and pathophysiological processes of immune cells,these findings reveal a potential new therapeutic target to help mitigate sepsis survivors’ susceptibility to secondary infections. Graphical abstract Highlights•Sepsis survivors demonstrate dysfunctional CD4 T cell immunity•Sepsis induces persistent mitochondrial dysfunction in CD4 T cells•Post-septic CD4 T cells are highly glycolytic and exhibit a Th17 phenotype•Sepsis impairs the CD4 T cell recall response Physiology; Molecular biology; Immunology; Components of the immune system View Publication

SummaryEnvironmental lipids are essential for fueling tumor energetics,but whether these exogenous lipids transported into cancer cells facilitate immune escape remains unclear. Here,we find that CD36,a transporter for exogenous lipids,promotes acute myeloid leukemia (AML) immune evasion. We show that,separately from its established role in lipid oxidation,CD36 on AML cells senses oxidized low-density lipoprotein (OxLDL) to prime the TLR4-LYN-MYD88-nuclear factor κB (NF-κB) pathway,and exogenous palmitate transfer via CD36 further potentiates this innate immune pathway by supporting ZDHHC6-mediated MYD88 palmitoylation. Subsequently,NF-κB drives the expression of immunosuppressive genes that inhibit anti-tumor T cell responses. Notably,high-fat-diet or hypomethylating agent decitabine treatment boosts the immunosuppressive potential of AML cells by hijacking CD36-dependent innate immune signaling,leading to a dampened therapeutic effect. This work is of translational interest because lipid restriction by US Food and Drug Administration (FDA)-approved lipid-lowering statin drugs improves the efficacy of decitabine therapy by weakening leukemic CD36-mediated immunosuppression. Graphical abstract Highlights•CD36 on AML cells suppresses T cell proliferation independently of lipid oxidation•OxLDL and palmitate synergize to inhibit T cell activity via CD36 signaling in AML cells•Targeting CD36 signaling with statins improves the efficacy of decitabine therapy in AML Guo et al. find that OxLDL and palmitate uptake by AML cells synergistically upregulates CD36-mediated innate immune signaling to suppress T cell activity. High-fat-diet or decitabine treatment dampened the therapeutic effect by hijacking CD36 signaling. Targeting the CD36 immunosuppressive pathway with statins improves the efficacy of decitabine therapy in AML. View Publication