技术资料

Chronic lung allograft dysfunction is the major barrier to long-term survival in lung transplant recipients. Evidence supports type 1 alloimmunity as the predominant response in acute/chronic lung rejection,but the immunoregulatory mechanisms remain incompletely understood. We studied the combinatorial F-box E3 ligase system: F-box protein 3 (FBXO3; proinflammatory) and F-box and leucine-rich repeat protein 2 (FBXL2; anti-inflammatory and regulates TNFR-associated factor [TRAF] protein). Using the mouse orthotopic lung transplant model,we evaluated allografts from BALB/c †’ C57BL/6 (acute rejection; day 10) and found significant induction of FBXO3 and diminished FBXL2 protein along with elevated T-bet,IFN-$\gamma$,and TRAF proteins 1-5 compared with isografts. In the acute model,treatment with costimulation blockade (MR1/CTLA4-Ig) resulted in attenuated FBXO3,preserved FBXL2,and substantially reduced T-bet,IFN-$\gamma$,and TRAFs 1-5,consistent with a key role for type 1 alloimmunity. Immunohistochemistry revealed significant changes in the FBXO3/FBXL2 balance in airway epithelia and infiltrating mononuclear cells during rejection compared with isografts or costimulation blockade-treated allografts. In the chronic lung rejection model,DBA/2J/C57BL/6F1 > DBA/2J (day 28),we observed persistently elevated FBXO3/FBXL2 balance and T-bet/IFN-$\gamma$ protein and similar findings from lung transplant recipient lungs with chronic lung allograft dysfunction versus controls. We hypothesized that FBXL2 regulated T-bet and found FBXL2 was sufficient to polyubiquitinate T-bet and coimmunoprecipitated with T-bet on pulldown experiments and vice versa in Jurkat cells. Transfection with FBXL2 diminished T-bet protein in a dose-dependent manner in mouse lung epithelial cells. In testing type 1 cytokines,TNF-$\alpha$ was found to negatively regulate FBXL2 protein and mRNA levels. Together,our findings show the combinatorial E3 ligase FBXO3/FBXL2 system plays a role in the regulation of T-bet through FBXL2,with negative cross-regulation of TNF-$\alpha$ on FBXL2 during lung allograft rejection. View Publication

BACKGROUND Current immunotherapies still have limited successful rates among cancers. It is now recognized that T cell functional state in the tumor microenvironment (TME) is a key determinant for effective antitumor immunity and immunotherapy. In addition to exhaustion,cellular senescence in tumor-infiltrating T cells (TILs) has recently been identified as an important T cell dysfunctional state induced by various malignant tumors. Therefore,a better understanding of the molecular mechanism responsible for T cell senescence in the TME and development of novel strategies to prevent effector T cell senescence are urgently needed for cancer immunotherapy. METHODS Senescent T cell populations in the TMEs in mouse lung cancer,breast cancer,and melanoma tumor models were evaluated. Furthermore,T cell senescence induced by mouse tumor and regulatory T (Treg) cells in vitro was determined with multiple markers and assays,including real-time PCR,flow cytometry,and histochemistry staining. Loss-of-function strategies with pharmacological inhibitors and the knockout mouse model were used to identify the potential molecules and pathways involved in T cell senescence. In addition,melanoma mouse tumor immunotherapy models were performed to explore the synergistical efficacy of antitumor immunity via prevention of tumor-specific T cell senescence combined with anti-programmed death-ligand 1 (anti-PD-L1) checkpoint blockade therapy. RESULTS We report that both mouse malignant tumor cells and Treg cells can induce responder T cell senescence,similar as shown in human Treg and tumor cells. Accumulated senescent T cells also exist in the TME in tumor models of lung cancer,breast cancer and melanoma. Induction of ataxia-telangiectasia mutated protein (ATM)-associated DNA damage is the cause for T cell senescence induced by both mouse tumor cells and Treg cells,which is also regulated by mitogen-activated protein kinase (MAPK) signaling. Furthermore,blockages of ATM-associated DNA damage and/or MAPK signaling pathways in T cells can prevent T cell senescence mediated by tumor cells and Treg cells in vitro and enhance antitumor immunity and immunotherapy in vivo in adoptive transfer T cell therapy melanoma models. Importantly,prevention of tumor-specific T cell senescence via ATM and/or MAPK signaling inhibition combined with anti-PD-L1 checkpoint blockade can synergistically enhance antitumor immunity and immunotherapy in vivo. CONCLUSIONS These studies prove the novel concept that targeting both effector T cell senescence and exhaustion is an effective strategy and can synergistically enhance cancer immunotherapy. View Publication

Na{\{i}}ve CD8+ T cells can differentiate into effector (Teff) memory (Tmem) or exhausted (Tex) T cells. These developmental pathways are associated with distinct transcriptional and epigenetic changes that endow cells with different functional capacities and therefore therapeutic potential. The molecular circuitry underlying these developmental trajectories and the extent of heterogeneity within Teff Tmem and Tex populations remain poorly understood. Here we used the lymphocytic choriomeningitis virus model of acute-resolving and chronic infection to address these gaps by applying longitudinal single-cell RNA-sequencing (scRNA-seq) and single-cell assay for transposase-accessible chromatin sequencing (scATAC-seq) analyses. These analyses uncovered new subsets including a subpopulation of Tex cells expressing natural killer cell-associated genes that is dependent on the transcription factor Zeb2 as well as multiple distinct TCF-1+ stem/progenitor-like subsets in acute and chronic infection. These data also revealed insights into the reshaping of Tex subsets following programmed death 1 (PD-1) pathway blockade and identified a key role for the cell stress regulator Btg1 in establishing the Tex population. Finally these results highlighted how the same biological circuits such as cytotoxicity or stem/progenitor pathways can be used by CD8+ T cell subsets with highly divergent underlying chromatin landscapes generated during different infections." View Publication

OBJECTIVE Systemic sclerosis (SSc) is a complex autoimmune disease with a strong genetic component. However,most of the genes associated with the disease are still unknown because associated variants affect mostly noncoding intergenic elements of the genome. We used functional genomics to translate the genetic findings into a better understanding of the disease. METHODS Promoter capture Hi-C and RNA-sequencing experiments were performed in CD4+ T cells and CD14+ monocytes from 10 SSc patients and 5 healthy controls to link SSc-associated variants with their target genes,followed by differential expression and differential interaction analyses between cell types. RESULTS We linked SSc-associated loci to 39 new potential target genes and confirmed 7 previously known SSc-associated genes. We highlight novel causal genes,such as CXCR5,as the most probable candidate gene for the DDX6 locus. Some previously known SSc-associated genes,such as IRF8,STAT4,and CD247,showed cell type-specific interactions. We also identified 15 potential drug targets already in use in other similar immune-mediated diseases that could be repurposed for SSc treatment. Furthermore,we observed that interactions were directly correlated with the expression of important genes implicated in cell type-specific pathways and found evidence that chromatin conformation is associated with genotype. CONCLUSION Our study revealed potential causal genes for SSc-associated loci,some of them acting in a cell type-specific manner,suggesting novel biologic mechanisms that might mediate SSc pathogenesis. View Publication

B cells orchestrate autoimmune responses in patients with systemic lupus erythematosus (SLE),but broad-based B cell-directed therapies show only modest efficacy while blunting humoral immune responses to vaccines and inducing immunosuppression. Development of more effective therapies targeting pathogenic clones is a currently unmet need. Here,we demonstrate enhanced activation of the ATR/Chk1 pathway of the DNA damage response (DDR) in B cells of patients with active SLE disease. Treatment of B cells with type I IFN,a key driver of immunity in SLE,induced expression of ATR via binding of interferon regulatory factor 1 to its gene promoter. Pharmacologic targeting of ATR in B cells,via a specific inhibitor (VE-822),attenuated their immunogenic profile,including proinflammatory cytokine secretion,plasmablast formation,and antibody production. Together,these findings identify the ATR-mediated DDR axis as the orchestrator of the type I IFN-mediated B cell responses in SLE and as a potential novel therapeutic target. View Publication

Rift Valley fever virus (RVFV) is a hemorrhagic fever virus with the potential for significant economic and public health impact. Vaccination with an attenuated strain,DelNSsRVFV,provides protection from an otherwise lethal RVFV challenge,but mechanistic determinants of protection are undefined. In this study,a murine model was used to assess the contributions of humoral and cellular immunity to DelNSsRVFV-mediated protection. Vaccinated mice depleted of T cells were protected against subsequent challenge,and passive transfer of immune serum from vaccinated animals to na{\{i}}ve animals was also protective demonstrating that T cells were dispensable in the presence of humoral immunity and that humoral immunity alone was sufficient. Animals depleted of B cells and then vaccinated were protected against challenge. Total splenocytes but not T cells alone B cells alone or B??+??T cells harvested from vaccinated animals and then transferred to na{\"{i}}ve animals were sufficient to confer protection suggesting that multiple cellular interactions were required for effective cellular immunity. Together these data indicate that humoral immunity is sufficient to confer vaccine-mediated protection and suggests that cellular immunity plays a role in protection that requires the interaction of various cellular components." View Publication

Immunotherapy has revolutionized cancer treatment,but preclinical models are required to understand immunotherapy resistance mechanisms underlying patient relapse. This protocol describes how to generate an acquired resistance humanized in vivo model to immunotherapies in patient-derived xenografts (PDX). We detail steps to inject human CD34+ cells into NSG mice,followed by generation of immunoresistant PDX in humanized mice. This approach recapitulates the human immune system,allowing investigators to generate preclinical resistance models to different immunotherapies for identifying the resistant phenotype. For complete details on the use and execution of this protocol,please refer to Mart{\'{i}}nez-Sabadell et al.,2022 and Arenas et al. (2021). View Publication

Mesenchymal stem cells (MSCs) are attractive alternatives to conventional anti-asthmatic drugs for severe asthma. Mechanisms underlying the anti-asthmatic effects of MSCs have not yet been elucidated. This study evaluated the anti-asthmatic effects of intravenously administered MSCs,focusing on macrophages and monocytes. Seven-week-old transgenic (Tg) mice with lung-specific overexpression of IL-13 were used to simulate chronic asthma. MSCs were intravenously administered four days before sampling. We examined changes in immune cell subpopulations,gene expression,and histological phenotypes. IL-13 Tg mice exhibited diverse features of chronic asthma,including severe type 2 inflammation,airway fibrosis,and mucus metaplasia. Intravenous administration of MSCs attenuated these asthmatic features just four days after a single treatment. MSC treatment significantly reduced SiglecF-CD11c-CD11b+ monocyte-derived macrophages (MoMs) and inhibited the polarization of MoMs into M2 macrophages,especially M2a and M2c. Furthermore,MSCs downregulated the excessive accumulation of Ly6c- monocytes in the lungs. While an intravenous adoptive transfer of Ly6c- monocytes promoted the infiltration of MoM and Th2 inflammation,that of MSC-exposed Ly6c- monocytes did not. Ex vivo Ly6c- MoMs upregulated M2-related genes,which were reduced by MSC treatment. Molecules secreted by Ly6c- MoMs from IL-13 Tg mice lungs upregulated the expression of fibrosis-related genes in fibroblasts,which were also suppressed by MSC treatment. In conclusion,intravenously administered MSCs attenuate asthma phenotypes of chronic asthma by modulating macrophages. Identifying M2 macrophage subtypes revealed that exposure to MSCs transforms the phenotype and function of macrophages. We suggest that Ly6c- monocytes could be a therapeutic target for asthma management. View Publication

Multiple myeloma (MM) remains an incurable malignancy of plasma cells despite constantly evolving therapeutic approaches including various types of immunotherapy. Increased arginase activity has been associated with potent suppression of T-cell immune responses in different types of cancer. Here,we investigated the role of arginase 1 (ARG1) in V$\kappa$*MYC model of MM in mice. ARG1 expression in myeloid cells correlated with tumor progression and was accompanied by a systemic drop in EY-arginine levels. In MM-bearing mice antigen-induced proliferation of adoptively transferred T-cells was strongly suppressed and T-cell proliferation was restored by pharmacological arginase inhibition. Progression of V$\kappa$*MYC tumors was significantly delayed in mice with myeloid-specific ARG1 deletion. Arginase inhibition effectively inhibited tumor progression although it failed to augment anti-myeloma effects of bortezomib. However,arginase inhibitor completely prevented development of bortezomib-induced cardiotoxicity in mice. Altogether,these findings indicate that arginase inhibitors could be further tested as a complementary strategy in multiple myeloma to mitigate adverse cardiac events without compromising antitumor efficacy of proteasome inhibitors. View Publication

Same day processing of biospecimens such as blood is not always feasible,which presents a challenge for research programs seeking to study a broad population or to characterize patients with rare diseases. Recruiting sites may not be equipped to process blood samples and variability in timing and technique employed to isolate peripheral blood mononuclear cells (PBMCs) at local sites may compromise reproducibility across patients. One solution is to send whole blood collected by routine phlebotomy via overnight courier to the testing site under ambient conditions. Determining the impact of shipping on subsequent leukocyte responses is a necessary prerequisite to any experimental analysis derived from transported samples. To this end,whole blood was collected from healthy control subjects and processed fresh or at 6,24 and 48 h after collection and handling under modeled shipping conditions. At endpoint,whole blood was assessed via a complete blood count with differential and immunophenotyped using a standardized panel of antibodies [HLADR,CD66b,CD3,CD14,CD16]. PBMCs and neutrophils were isolated from whole blood and subjected to ex vivo stimulation with lipopolysaccharide and heat-killed Staphylococcus aureus. Stimulated release of cytokines and chemokines was assessed by cytometric bead array. RNA was also isolated from PBMCs to analyze transcriptional changes induced by shipping. The complete blood count with differential revealed that most parameters were maintained in shipped blood held for 24 h at ambient temperature. Immunophenotyping indicated preservation of cellular profiles at 24 h,although with broadening of some populations and a decrease in CD16 intensity on classical monocytes. At the transcriptional level,RNAseq analysis identified upregulation of a transcription factor module associated with inflammation in unstimulated PBMCs derived from whole blood shipped overnight. However,these changes were limited in both scale and number of impacted genes. Ex vivo stimulation of PBMCs further revealed preservation of functional responses in cells isolated from shipped blood held for 24 h at ambient temperature. However,neutrophil responses were largely abrogated by this time. By 48 h neither cell population responded within normal parameters. These findings indicate that robust immunophenotyping and PBMC stimulated response profiles are maintained in whole blood shipped overnight and processed within 24 h of collection,yielding results that are representative of those obtained from the sample immediately following venipuncture. This methodology is feasible for many patient recruitment sites to implement and allows for sophisticated immunological analysis of patient populations derived from large geographic areas. With regard to rare disease research,this meets a universal need to enroll patients in sufficient numbers for immunoprofiling and discovery of underlying pathogenic mechanisms. View Publication

BACKGROUND CD8+ T cells are important for protective immunity against intracellular pathogens. Excessive amounts of antigen and/or inflammatory signals often lead to the gradual deterioration of CD8+ T cell function,a state called exhaustion". However the association between CD8+ T cell exhaustion and acute respiratory distress syndrome (ARDS) has not been studied. This study was conducted to elucidate how CD8+ T cells and inhibitory receptors were related to the clinical prognosis of ARDS. METHODS A prospective observational study in an emergency department enrolled patients who were diagnosed with sepsis-associated ARDS according to the sepsis-3 criteria and Berlin definition. Peripheral blood samples were collected within 24??h post recruitment. CD8+ T cell count proliferation ratio cytokine secretion and the expression of coinhibitory receptors were assayed. RESULTS Sixty-two patients with ARDS met the inclusion criteria. CD8+ T cell counts and proliferation rates were dramatically decreased in non-surviving ARDS patients. Increasing programmed cell death 1 (PD-1) expression on the CD8+ T cell surface was seen in patients with worse organ function while an increasing level of T cell immunoglobulin mucin-3 (Tim-3) was associated with a longer duration of the shock. Kaplan-Meier analysis showed that low CD8+ T cell percentages and increased inhibitory molecule expression were significantly associated with a worse survival rate. CONCLUSIONS CD8+ T cells and coinhibitory receptors are promising independent prognostic markers of sepsis-induced ARDS and increased CD8+ T cell exhaustion is significantly correlated with poor prognosis." View Publication

Facile and sensitive detection and isolation of circulating tumor cells (CTCs) was achieved using the aptamer-targeted magnetic nanoparticles (Apt-MNPs) in conjugation with a microfluidic device. Apt-MNPs were developed by the covalent attachment of anti-MUC1 aptamer to the silica-coated magnetic nanoparticles via the glutaraldehyde linkers. Apt-MNPs displayed high stability and functionality after 6 months of storage at 4 °C. The specific microfluidic device consisting of mixing,sorting and separation modules was fabricated through conventional photo- and soft-lithography by using polydimethylsiloxane. The capture efficiency of Apt-MNPs was first studied in vitro on MCF-7 and MDA-MB-231 cancer cell lines in the bulk and microfluidic platforms. The cell capture yields of more than 91% were obtained at the optimum condition after 60 minutes of exposure to 50 $\mu$g mL-1 Apt-MNPs with 10 to 106 cancer cells in different media. CTCs were also isolated efficiently from the blood samples of breast cancer patients and successfully propagated in vitro. The isolated CTCs were further characterized using immunofluorescence staining. The overall results indicated the high potential of the present method for the detection and capture of CTCs. View Publication