参考文献

The increased incidence of inflammatory bowel disease (IBD) has become a global phenomenon that could be related to adoption of a Western life-style. Westernization of dietary habits is partly characterized by enrichment with the $\omega$-6 polyunsaturated fatty acid (PUFA) arachidonic acid (AA),which entails risk for developing IBD. Glutathione peroxidase 4 (GPX4) protects against lipid peroxidation (LPO) and cell death termed ferroptosis. We report that small intestinal epithelial cells (IECs) in Crohn's disease (CD) exhibit impaired GPX4 activity and signs of LPO. PUFAs and specifically AA trigger a cytokine response of IECs which is restricted by GPX4. While GPX4 does not control AA metabolism,cytokine production is governed by similar mechanisms as ferroptosis. A PUFA-enriched Western diet triggers focal granuloma-like neutrophilic enteritis in mice that lack one allele of Gpx4 in IECs. Our study identifies dietary PUFAs as a trigger of GPX4-restricted mucosal inflammation phenocopying aspects of human CD. View Publication

COVID-19 is currently a global pandemic,but human immune responses to the virus remain poorly understood. We analyzed 125 COVID-19 patients,and compared recovered to healthy individuals using high dimensional cytometry. Integrated analysis of {\~{}}200 immune and {\~{}}50 clinical features revealed activation of T cell and B cell subsets in a proportion of patients. A subgroup of patients had T cell activation characteristic of acute viral infection and plasmablast responses reaching {\textgreater}30{\%} of circulating B cells. However,another subgroup had lymphocyte activation comparable to uninfected subjects. Stable versus dynamic immunological signatures were identified and linked to trajectories of disease severity change. These analyses identified three immunotypes" associated with poor clinical trajectories versus improving health. These immunotypes may have implications for the design of therapeutics and vaccines for COVID-19." View Publication

Aim To analyse the ability of mesenchymal stem cells (MSCs) to regulate interleukin 6 (IL-6) and transforming growth factor (TGF-$\beta$) expression in vitro under co-culture conditions in human systemic lupus erythematosus (SLE). Method This study used a post-test group design that used peripheral blood mononuclear cells (PBMCs) from SLE patients at Kariadi Hospital,Semarang,Indonesia,and MSCs from a human umbilical cord. The cells were divided into two groups. The control group of PBMCs was treated with a standard medium,and the treatment group was co-cultured with the MSCs at a 1:40 ratio. Following 24 h incubation,the levels of IL-6 and TGF-$\beta$ released in the culture medium were measured using a specific ELISA assay. Results This study showed a significant decrease in IL-6 level (p{\textless}0.05) and a significant increase in TGF-$\beta$ level (p{\textless}0.001) following 24 h of co-culture incubation of human SLE PBMCs cells and MSCs. Conclusion The PBMCs-to-MSCs ratio of 1:40 can regulate the IL-6 and TGF-$\beta$ levels in human SLE PBMCs. View Publication

Coinfection with hepatitis C virus (HCV) influences HIV reservoir size. However,it is unknown whether this coinfection also induces a higher provirus transcription. Viral transcription is promoted by synergy between cellular factors such as NF-$\kappa$B and the viral regulator Tat. The impact of HCV coinfection on HIV provirus transcription was analyzed in resting (r)CD4 T+ cells (CD3+CD4+CD25-CD69-HLADR-) and rCD4 T cells-depleted PBMCs (rCD4 T- PBMCs) from a multicenter cross-sectional study of 115 cART-treated HIV patients: 42 HIV+/HCV+ coinfected individuals (HIV+/HCV+),34 HIV+ patients with HCV spontaneous clearance (HIV+/HCV-) and 39 HIV patients (HIV+). Viral transcription was assessed in total RNA through the quantification of unspliced,single spliced,and multiple spliced viral mRNAs by qPCR. Linear correlations between viral reservoir size and viral splicing were determined. A 3-fold increase of multiple spliced transcripts in rCD4 T+ cells of HIV+/HCV+ patients was found compared to HIV+ individuals (p {\textless} 0.05). As Tat is synthesized by multiple splicing,the levels of Tat were also quantified in these patients. Significant differences in single and multiple spliced transcripts were also observed in rCD4 T- PBMCs. Levels of multiple spliced mRNAs were increased in rCD4 T+ cells isolated from HIV+/HCV+ subjects,which could indicate a higher Tat activity in these cells despite their resting state. View Publication

Inhibitory receptors (IRs) function as critical regulators of immune responses by tempering T cell activity. In humans,several persisting viruses as well as cancers exploit IR signaling by upregulating IR ligands,resulting in suppression of T cell function (i.e.,exhaustion). This allows escape from immune surveillance and continuation of disease. Here,we report the design,implementation,and results of a phenotypic high-throughput screen for molecules that modulate CD8+ T cell activity. We identify 19 compounds from the ReFRAME drug-repurposing collection that restore cytokine production and enhance the proliferation of exhausted T cells. Analysis of our top hit,ingenol mebutate,a protein kinase C (PKC) inducing diterpene ester,reveals a role for this molecule in overriding the suppressive signaling cascade mediated by IR signaling on T cells. Collectively,these results demonstrate a disease-relevant methodology for identifying modulators of T cell function and reveal new targets for immunotherapy. View Publication

Checkpoint-inhibitor (CPI) immunotherapy has achieved remarkable clinical success,yet its efficacy in 'immunologically cold' tumours has been modest. Interleukin-12 (IL-12) is a powerful cytokine that activates the innate and adaptive arms of the immune system; however,the administration of IL-12 has been associated with immune-related adverse events. Here we show that,after intravenous administration of a collagen-binding domain fused to IL-12 (CBD-IL-12) in mice bearing aggressive mouse tumours,CBD-IL-12 accumulates in the tumour stroma due to exposed collagen in the disordered tumour vasculature. In comparison with the administration of unmodified IL-12,CBD-IL-12 induced sustained intratumoural levels of interferon-$\gamma$,substantially reduced its systemic levels as well as organ damage and provided superior anticancer efficacy,eliciting complete regression of CPI-unresponsive breast tumours. Furthermore,CBD-IL-12 potently synergized with CPI to eradicate large established melanomas,induced antigen-specific immunological memory and controlled tumour growth in a genetically engineered mouse model of melanoma. CBD-IL-12 may potentiate CPI immunotherapy for immunologically cold tumours. View Publication

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a complex disease with no known cause or mechanism. There is an increasing appreciation for the role of immune and metabolic dysfunction in the disease. ME/CFS has historically presented in outbreaks,often has a flu-like onset,and results in inflammatory symptoms. Patients suffer from severe fatigue and post-exertional malaise. There is little known about the metabolism of specific immune cells in ME/CFS patients. To investigate immune metabolism in ME/CFS,we isolated CD4+ and CD8+ T cells from 53 ME/CFS patients and 45 healthy controls. We analyzed glycolysis and mitochondrial respiration in resting and activated T cells,along with markers related to cellular metabolism,and plasma cytokines. We found that ME/CFS CD8+ T cells have reduced mitochondrial membrane potential compared to healthy controls. Both CD4+ and CD8+ T cells from ME/CFS patients had reduced glycolysis at rest,while CD8+ T cells also had reduced glycolysis following activation. ME/CFS patients had significant correlations between measures of T cell metabolism and plasma cytokine abundance that differed from healthy control subjects. Our data indicate that patients have impaired T cell metabolism consistent with ongoing immune alterations in ME/CFS that may illuminate the mechanism behind this disease. View Publication

Drug resistance and relapse remain key challenges in pancreatic cancer. Here,we have used RNA sequencing (RNA-seq),chromatin immunoprecipitation (ChIP)-seq,and genome-wide CRISPR analysis to map the molecular dependencies of pancreatic cancer stem cells,highly therapy-resistant cells that preferentially drive tumorigenesis and progression. This integrated genomic approach revealed an unexpected utilization of immuno-regulatory signals by pancreatic cancer epithelial cells. In particular,the nuclear hormone receptor retinoic-acid-receptor-related orphan receptor gamma (ROR$\gamma$),known to drive inflammation and T cell differentiation,was upregulated during pancreatic cancer progression,and its genetic or pharmacologic inhibition led to a striking defect in pancreatic cancer growth and a marked improvement in survival. Further,a large-scale retrospective analysis in patients revealed that ROR$\gamma$ expression may predict pancreatic cancer aggressiveness,as it positively correlated with advanced disease and metastasis. Collectively,these data identify an orthogonal co-option of immuno-regulatory signals by pancreatic cancer stem cells,suggesting that autoimmune drugs should be evaluated as novel treatment strategies for pancreatic cancer patients. View Publication

The SARS-CoV-2 pandemic affecting the human respiratory system severely challenges public health and urgently demands for increasing our understanding of COVID-19 pathogenesis,especially host factors facilitating virus infection and replication. SARS-CoV-2 was reported to enter cells via binding to ACE2,followed by its priming by TMPRSS2. Here,we investigate ACE2 and TMPRSS2 expression levels and their distribution across cell types in lung tissue (twelve donors,39,778 cells) and in cells derived from subsegmental bronchial branches (four donors,17,521 cells) by single nuclei and single cell RNA sequencing,respectively. While TMPRSS2 is strongly expressed in both tissues,in the subsegmental bronchial branches ACE2 is predominantly expressed in a transient secretory cell type. Interestingly,these transiently differentiating cells show an enrichment for pathways related to RHO GTPase function and viral processes suggesting increased vulnerability for SARS-CoV-2 infection. Our data provide a rich resource for future investigations of COVID-19 infection and pathogenesis. View Publication

Why ocular mucosa is paucibacterial is unknown. Many different mechanisms have been suggested but the comprehensive experimental studies are sparse. We found that a deficiency in L-plastin (LCP1),an actin bundling protein,resulted in an ocular commensal overgrowth,characterized with increased presence of conjunctival Streptococcal spp. The commensal overgrowth correlated with susceptibility to P. aeruginosa-induced keratitis. L-plastin knock-out (KO) mice displayed elevated bacterial burden in the P. aeruginosa-infected corneas,altered inflammatory responses,and compromised bactericidal activity. Mice with ablation of LPL under the LysM Cre (LysM. Cre pos LPLfl/fl ) and S100A8 Cre (S100A8.Cre pos LPLfl/fl ) promoters had a similar phenotype to the LPL KOs mice. In contrast,infected CD11c.Cre pos LPLfl/fl mice did not display elevated susceptibility to infection,implicating the myeloid L-plastin-sufficient cells (e.g.,macrophages and neutrophils) in maintaining ocular homeostasis. Mechanistically,the elevated commensal burden and the susceptibility to infection were linked to defects in neutrophil frequencies at steady state and during infection and compromised bactericidal activities upon priming. Macrophage exposure to commensal organisms primed neutrophil responses to P. aeruginosa,augmenting PMN bactericidal capacity in an L-plastin dependent manner. Cumulatively,our data highlight the importance of neutrophils in controlling ocular paucibacteriality,reveal molecular and cellular events involved in the process,and suggest a link between commensal exposure and resistance to infection. View Publication