技术资料

Chimeric-antigen receptor (CAR) T-cell immunotherapy employs autologous-T cells modified with an antigen-specific CAR. Current CAR-T manufacturing processes tend to yield products dominated by effector T cells and relatively small proportions of long-lived memory T cells. Those few cells are a so-called stem cell memory T (TSCM) subset,which express na{\{i}}ve T-cell markers and are capable of self-renewal and oligopotent differentiation into effector phenotypes. Increasing the proportion of this subset may lead to more effective therapies by improving CAR-T persistence; however there is currently no standardized protocol for the effective generation of CAR-TSCM cells. Here we present a simplified protocol enabling efficient derivation of gene-modified TSCM cells: Stimulation of na{\"{i}}ve CD8+ T cells with only soluble anti-CD3 antibody and culture with IL-7 and IL-15 was sufficient for derivation of CD8+ T cells harboring TSCM phenotypes and oligopotent capabilities. These in-vitro expanded TSCM cells were engineered with CARs targeting the HIV-1 envelope protein as well as the CD19 molecule and demonstrated effector activity both in vitro and in a xenograft mouse model. This simple protocol for the derivation of CAR-TSCM cells may facilitate improved adoptive immunotherapy." View Publication

BACKGROUND Glioblastoma (GBM) is the most common and aggressive form of primary brain tumor. Although numerous postoperative therapeutic strategies have already been developed,including radiotherapy,tumors inevitably recur after several years of treatment. The coinhibitory molecule B7-H4 negatively regulates T cell immune responses and promotes immune escape. Exosomes mediate intercellular communication and initiate immune evasion in the tumor microenvironment (TME). OBJECTIVE This study aimed to determine whether B7-H4 is upregulated by radiation and loaded into exosomes,thus contributing to immunosuppression and enhancing tumor growth. METHODS Iodixanol density-gradient centrifugation and flow cytometry were used to verify exosomal B7-H4. Na{\{i}}ve T cells were differentiated into Th1 cells with or without exosomes. T cell-secreted cytokines and markers of T cell subsets were measured. Mechanistically the roles of B7-H4 and ALIX in GBM were analyzed using databases and tissue samples. Co-immunoprecipitation and pull-down assays were used to tested the direct interactions between ATM and ALIX or STAT3. In vitro ATM kinase assays western blotting and site-directed mutation were used to assess ATM-mediated STAT3 phosphorylation. Finally the contribution of exosomal B7-H4 to immunosuppression and tumor growth was investigated in vivo. RESULTS Exosomes from irradiated GBM cells decreased the anti-tumor immune response of T cell in vitro and in vivo via delivered B7-H4. Mechanistically irradiation promoted exosome biogenesis by increasing the ATM-ALIX interaction. Furthermore the ATM-phosphorylated STAT3 was found to directly binds to the B7-H4 promoter to increase its expression. Finally the radiation-induced increase in exosomal B7-H4 induced FoxP3 expression during Th1 cell differentiation via the activated STAT1 pathway. In vivo exosomal B7-H4 decreased the radiation sensitivity of GBM cells and reduced the survival of GBM mice model. CONCLUSION This study showed that radiation-enhanced exosomal B7-H4 promoted immunosuppression and tumor growth hence defining a direct link between irradiation and anti-tumor immune responses. Our results suggest that co-administration of radiotherapy with anti-B7-H4 therapy could improve local tumor control and identify exosomal B7-H4 as a potential tumor biomarker." View Publication

The biological macromolecule Nocardia rubra cell-wall skeleton (Nr-CWS) has well-established immune-stimulating and anti-tumor activities. However,the role of Nr-CWS on natural killer (NK) cells remains unclear. Here,we explore the function and related mechanisms of Nr-CWS on NK cells. Using a tumor-bearing model,we show that Nr-CWS has slightly effect on solid tumor. In addition,using a tumor metastasis model,we show that Nr-CWS suppresses the lung metastasis induced by B16F10 melanoma cells in mice,which indicates that Nr-CWS may up-regulate the function of NK cells. Further investigation demonstrated that Nr-CWS can increase the expression of TRAIL and FasL on spleen NK cells from Nr-CWS treated B16F10 tumor metastasis mice. The spleen index and serum levels of TNF-$\alpha$,IFN-$\gamma$,and IL-2 in B16F10 tumor metastasis mice treated with Nr-CWS were significantly increased. In vitro,the studies using purified or sorted NK cells revealed that Nr-CWS increases the expression of CD69,TRAIL,and FasL,decreases the expression of CD27,and enhances NK cell cytotoxicity. The intracellular expression of IFN-$\gamma$,TNF-$\alpha$,perforin (prf),granzyme-B (GrzB),and secreted TNF-$\alpha$,IFN-$\gamma$,IL-6 of the cultured NK cells were significantly increased after treatment with Nr-CWS. Overall,the findings indicate that Nr-CWS could suppress the lung metastasis induced by B16F10 melanoma cells,which may be exerted through its effect on NK cells by promoting NK cell terminal differentiation (CD27lowCD11bhigh),and up-regulating the production of cytokines and cytotoxic molecules. View Publication

The concept of exploiting tumor intrinsic deficiencies in DNA damage repair mechanisms by inhibiting compensatory DNA repair pathways is well established. For example,ATM-deficient cells show increased sensitivity to the ATR inhibitor ceralasertib. DNA damage response (DDR)-deficient cells are also more sensitive to DNA damaging agents like the DNA crosslinker pyrrolobenzodiazepine (PBD) SG-3199. However,additional antitumor benefits from targeting the DDR pathways,which could operate through the activation of the innate immune system are less well studied. DNA accumulation in the cytosol acts as an immunogenic danger signal,inducing the expression of type-I interferon (IFN) stimulated genes (ISGs) by the activation of the cGAS-STING pathway. Here,we demonstrate that ATM -/- FaDu tumor cells have higher basal expression of ISGs when compared to WT cells and respond to ceralasertib and PBD SG-3199 by inducing higher levels of ISGs in a cGAS-STING-dependent manner. We show that sensitive tumor cells treated with ceralasertib and PBD SG-3199 activate dendritic cells (DCs) via a type-I IFN-dependent mechanism. However,STING deficiency in tumor cells does not prevent DC activation,suggesting that transactivation of the STING pathway occurs within DCs. Furthermore,depletion of the cytosolic DNA exonuclease TREX1 in tumor cells increases DC activation in response to PBD SG-3199-treated tumor cells,indicating that an increase in tumor-derived cytosolic DNA may further enhance DC activation. In summary,in this study,we show that ceralasertib and PBD SG-3199 treatment not only intrinsically target tumor cells but also extrinsically increase tumor cell immunogenicity by inducing DC activation,which is enhanced in ATM-deficient cells. View Publication

Although studies have identified the presence of gut-associated cells in the enthesis of joints affected by spondylarthritis (SpA),a direct link through cellular transit between the gut and joint has yet to be formally demonstrated. Using KikGR transgenic mice to label in situ and track cellular trafficking from the distal colon to the joint under inflammatory conditions of both the gut and joint,we demonstrate bona-fide gut-joint trafficking of T cells from the colon epithelium,also called intraepithelial lymphocytes (IELs),to distal sites including joint enthesis,the pathogenic site of SpA. Similar to patients with SpA,colon IELs from the TNF$\Delta$ARE/+ mouse model of inflammatory bowel disease and SpA display heightened TNF production upon stimulation. Using ex vivo stimulation of photo-labeled gut-joint trafficked T cells from the popliteal lymph nodes of KikGR and KikGR TNF$\Delta$ARE/+ we saw that the CD4+ photo-labeled population was highly enriched for IL-17 competence in healthy as well as arthritic mice,however in the TNF$\Delta$ARE/+ mice these cells were additionally enriched for TNF. Using transfer of magnetically isolated IELs from TNF+/+ and TNF$\Delta$ARE/+ donors into Rag1 -/- hosts,we confirmed that IELs can exacerbate inflammatory processes in the joint. Finally,we blocked IEL recruitment to the colon epithelium using broad spectrum antibiotics in TNF$\Delta$ARE/+ mice. Antibiotic-treated mice had reduced gut-joint IEL migration,contained fewer Il-17A and TNF competent CD4+ T cells,and lessened joint pathology compared to untreated littermate controls. Together these results demonstrate that pro-inflammatory colon-derived IELs can exacerbate inflammatory responses in the joint through systemic trafficking,and that interference with this process through gut-targeted approaches has therapeutic potential in SpA. View Publication

While inhibitory Siglec receptors are known to regulate myeloid cells,less is known about their expression and function in lymphocytes subsets. Here we identified Siglec-7 as a glyco-immune checkpoint expressed on non-exhausted effector memory CD8+ T cells that exhibit high functional and metabolic capacities. Seahorse analysis revealed higher basal respiration and glycolysis levels of Siglec-7+ CD8+ T cells in steady state,and particularly upon activation. Siglec-7 polarization into the T cell immune synapse was dependent on sialoglycan interactions in trans and prevented actin polarization and effective T cell responses. Siglec-7 ligands were found to be expressed on both leukemic stem cells and acute myeloid leukemia (AML) cells suggesting the occurrence of glyco-immune checkpoints for Siglec-7+ CD8+ T cells,which were found in patients' peripheral blood and bone marrow. Our findings project Siglec-7 as a glyco-immune checkpoint and therapeutic target for T cell-driven disorders and cancer. View Publication

BACKGROUND Ageing is a complex phenomenon that leads to decreased proliferative activity,loss of function of the cells,and cellular senescence. Senescence of the immune system exacerbates individual's immune response,both humoral and cellular but increases the frequency of infections. We hypothesized that physiological ageing of adaptive immune system occurs in recipients of allogeneic hematopoietic cells transplant (allo-HCT) at faster rate when compared to their respective donors since the small number of donor cells undergo immense proliferative stress restoring recipients hematopoiesis. We compared molecular characterizations of ageing between recipients and donors of allo-HCT: telomeric length and immunophenotypic changes in main lymphocyte subsets - CD4+,CD8+,CD19+,CD56+. RESULTS Median telomeric length (TL) of CD8+ lymphocytes was significantly longer in donors compared to recipients (on average 2,1 kb and 1,7 kb respectively,p??=??0,02). Similar trends were observed for CD4+ and CD19+ although the results did not reach statistical significance. We have also found trends in the immunophenotype between recipients and donors in the subpopulations of CD4+ (na{\{i}}ve and effector memory) CD8+ Eomes+ and B-lymphocytes (B1 and B2). Lower infection risk recipients had also a significantly greater percentage of NK cells (22 3%) than high-risk patients (9 3%) p??=??0 04. CONCLUSION Our data do not support the initial hypothesis of accelerated aging in the long term all-HCT recipients with the exception of the recipients lymphocytes (mainly CD8+) which present some molecular features characteristic for physiological ageing (telomeric shortening immunophenotype) when compared to their respective donors. However a history of lower infection numbers in HCT recipients seems to be associated with increased percentage of NK cells. The history of GVHD seems not to affect the rate of ageing. Therefore it is safe to conclude that the observed subtle differences between recipients' and donors' cells result mainly from the proliferative stress in the early period after allo-HCT and the difference between hosts' and recipients' microenvironments." View Publication

G-protein coupled receptor kinases (GRKs) participate in the regulation of chemokine receptors by mediating receptor desensitization. They can be recruited to agonist-activated G-protein coupled receptors (GPCRs) and phosphorylate their intracellular parts,which eventually blocks signal propagation and often induces receptor internalization. However,there is growing evidence that GRKs can also control cellular functions beyond GPCR regulation. Immune cells commonly express two to four members of the GRK family (GRK2,GRK3,GRK5,GRK6) simultaneously,but we have very limited knowledge about their interplay in primary immune cells. In particular,we are missing comprehensive studies comparing the role of this GRK interplay for (a) multiple GPCRs within one leukocyte type,and (b) one specific GPCR between several immune cell subsets. To address this issue,we generated mouse models of single,combinatorial and complete GRK knockouts in four primary immune cell types (neutrophils,T cells,B cells and dendritic cells) and systematically addressed the functional consequences on GPCR-controlled cell migration and tissue localization. Our study shows that combinatorial depletions of GRKs have pleiotropic and cell-type specific effects in leukocytes,many of which could not be predicted. Neutrophils lacking all four GRK family members show increased chemotactic migration responses to a wide range of GPCR ligands,whereas combinatorial GRK depletions in other immune cell types lead to pro- and anti-migratory responses. Combined depletion of GRK2 and GRK6 in T cells and B cells shows distinct functional outcomes for (a) one GPCR type in different cell types,and (b) different GPCRs in one cell type. These GPCR-type and cell-type specific effects reflect in altered lymphocyte chemotaxis in vitro and localization in vivo. Lastly,we provide evidence that complete GRK deficiency impairs dendritic cell homeostasis,which unexpectedly results from defective dendritic cell differentiation and maturation in vitro and in vivo. Together,our findings demonstrate the complexity of GRK functions in immune cells,which go beyond GPCR desensitization in specific leukocyte types. Furthermore,they highlight the need for studying GRK functions in primary immune cells to address their specific roles in each leukocyte subset. View Publication

BACKGROUND Myeloid-derived suppressor cells (MDSCs) can potently inhibit T-cell activity,promote growth and metastasis of tumor and contribute to resistance to immunotherapy. Targeting MDSCs to alleviate their protumor functions and immunosuppressive activities is intimately associated with cancer immunotherapy. Natural killer (NK) cells can engage in crosstalk with multiple myeloid cells to alter adaptive immune responses,triggering T-cell immunity. However,whether the NK-cell-MDSC interaction can modulate the T-cell immune response requires further study. Cryo-thermal therapy could induce the maturation of MDSCs by creating an acute inflammatory environment to elicit a CD4+ Th1-dominant immune response,but the mechanism regulating this process remains unclear. METHODS NK cells were depleted and NKG2D was blocked with monoclonal antibodies in vivo. MDSCs,NK cells and T cells were assessed by flow cytometry and isolated by magnetic-activated cell sorting (MACS). MDSCs and NK cells were cocultured with T cells to determine their immunological function. The transcriptional profiles of MDSCs were measured by qRT-PCR and RNA-sequencing. Isolated NK cells and MDSCs by MACS were cocultured to study the viability and maturation of MDSCs regulated by NK cells. TIMER was used to comprehensively examine the immunological,clinical,and genomic features of tumors. RESULTS NK-cell activation after cryo-thermal therapy decreased MDSC accumulation and reprogrammed immunosuppressive MDSCs toward a mature phenotype to promote T cell antitumor immunity. Furthermore,we discovered that NK cells could kill MDSCs via the NKG2D-NKG2DL axis and promote MDSC maturation by interferon gamma (IFN-$\gamma$) in response to NKG2D. In addition,CD4+ Th1-dominant antitumor immune response was dependent on NKG2D,which promoted the major histocompatibility complex …¡ pathway of MDSCs. High activated NK-cell infiltration and NKG2D level in tumors were positively correlated with better clinical outcomes. CONCLUSIONS Cryo-thermal therapy induces effective CD4+ Th1-dominant antitumor immunity by activating NK cells to reprogram MDSCs,providing a promising therapeutic strategy for cancer immunotherapy. View Publication

Pre-existent cardiovascular disease is a risk factor for weak anti-viral immunity,but underlying mechanisms remain undefined. Here,we report that patients with coronary artery disease (CAD) have macrophages (M??) that actively suppress the induction of helper T cells reactive to two viral antigens: the SARS-CoV2 Spike protein and the Epstein-Barr virus (EBV) glycoprotein 350. CAD M?? overexpressed the methyltransferase METTL3,promoting the accumulation of N�?-methyladenosine (m6A) in Poliovirus receptor (CD155) mRNA. m6A modifications of positions 1635 and 3103 in the 3'UTR of CD155 mRNA stabilized the transcript and enhanced CD155 surface expression. As a result,the patients' M?? abundantly expressed the immunoinhibitory ligand CD155 and delivered negative signals to CD4+ T cells expressing CD96 and/or TIGIT receptors. Compromised antigen-presenting function of METTL3hi CD155hi M?? diminished anti-viral T cell responses in vitro and in vivo. LDL and its oxidized form induced the immunosuppressive M?? phenotype. Undifferentiated CAD monocytes had hypermethylated CD155 mRNA,implicating post-transcriptional RNA modifications in the bone-marrow in shaping anti-viral immunity in CAD. View Publication

Ischemia/reperfusion (I/R) injury is mediated in large part by opening of the mitochondrial permeability transition pore (PTP). Consequently,inhibitors of the PTP hold great promise for the treatment of a variety of cardiovascular disorders. At present,PTP inhibition is obtained only through the use of drugs (e.g. cyclosporine A,CsA) targeting cyclophilin D (CyPD) which is a key modulator,but not a structural component of the PTP. This limitation might explain controversial findings in clinical studies. Therefore,we investigated the protective effects against I/R injury of small-molecule inhibitors of the PTP (63 and TR002) that do not target CyPD. Both compounds exhibited a dose-dependent inhibition of PTP opening in isolated mitochondria and were more potent than CsA. Notably,PTP inhibition was observed also in mitochondria devoid of CyPD. Compounds 63 and TR002 prevented PTP opening and mitochondrial depolarization induced by Ca2+ overload and by reactive oxygen species in neonatal rat ventricular myocytes (NRVMs). Remarkably,both compounds prevented cell death,contractile dysfunction and sarcomeric derangement induced by anoxia/reoxygenation injury in NRVMs at sub-micromolar concentrations,and were more potent than CsA. Cardioprotection was observed also in adult mouse ventricular myocytes and human iPSc-derived cardiomyocytes,as well as ex vivo in perfused hearts. Thus,this study demonstrates that 63 and TR002 represent novel cardioprotective agents that inhibit PTP opening independent of CyPD targeting. View Publication

The aberrant regulation of the epithelial barrier integrity is involved in many diseases of the digestive tract,including inflammatory bowel diseases and colorectal cancer. Intestinal epithelial cell organoid cultures provide new perspectives for analyses of the intestinal barrier in vitro. However,established methods of barrier function analyses from two dimensional cultures have to be adjusted to the analysis of three dimensional organoid structures. Here we describe the methodology for analysis of epithelial barrier function and molecular regulation in intestinal organoids. Barrier responses to interferon-$\gamma$ of intestinal organoids with and without epithelial cell-specific deletion of the interferon-$\gamma$-receptor 2 gene were used as a model system. The established method allowed monitoring of the kinetics of interferon-$\gamma$-induced permeability changes in living organoids. Proteolytic degradation and altered localization of the tight junction proteins claudin-2,-7,and - 15 was detected using confocal spinning disc microscopy with 3D reconstruction. Hessian analysis was used for quantification of re-localization of claudins. In summary,we provide a novel methodologic approach for quantitative analyses of intestinal epithelial barrier functions in the 3D organoid model. View Publication