技术资料

The development of neutralizing antibodies (inhibitors) against factor VIII (FVIII) is a major complication of hemophilia A treatment. The sole clinical therapy to restore FVIII tolerance in patients with inhibitors remains immune tolerance induction (ITI) which is expensive,difficult to administer and not always successful. Although not fully understood,the mechanism of ITI is thought to rely on inhibition of FVIII-specific B cells (1). Its efficacy might therefore be improved through more aggressive B cell suppression. Fc$\gamma$RIIB is an inhibitory Fc receptor that down-regulates B cell signaling when cross-linked with the B cell receptor (BCR). We sought to investigate if recombinant FVIII Fc (rFVIIIFc),an Fc fusion molecule composed of FVIII and the Fc region of immunoglobulin G1 (IgG1) (2),is able to inhibit B cell activation more readily than FVIII. rFVIIIFc was able to bind FVIII-exposed and na{\{i}}ve B cells from hemophilia A mice as well as a FVIII-specific murine B cell hybridoma line (413 cells). An anti-Fc$\gamma$RIIB antibody and FVIII inhibited binding suggesting that rFVIIIFc is able to interact with both Fc$\gamma$RIIB and the BCR. Furthermore incubation of B cells from FVIII-exposed mice and 413 cells with rFVIIIFc resulted in increased phosphorylation of SH-2 containing inositol 5-phosphatase (SHIP) when compared to FVIII. B cells from FVIII-exposed hemophilia A mice also exhibited decreased extracellular signal-regulated kinase (ERK) phosphorylation when exposed to rFVIIIFc. These differences were absent in B cells from na{\"{i}}ve non-FVIII exposed hemophilic mice suggesting an antigen-dependent effect. Finally rFVIIIFc was able to inhibit B cell calcium flux induced by anti-Ig F(ab)2. Our results therefore indicate that rFVIIIFc is able to crosslink Fc$\gamma$RIIB and the BCR of FVIII-specific B cells causing inhibitory signaling in these cells.""" View Publication

Well-differentiated primary human bronchial epithelial (HBE) cell cultures are vital for cystic fibrosis (CF) research,particularly for the development of cystic fibrosis transmembrane conductance regulator (CFTR) modulator drugs. Culturing of epithelial cells with irradiated 3T3 fibroblast feeder cells plus the RhoA kinase inhibitor Y-27632 (Y),termed conditionally reprogrammed cell (CRC) technology,enhances cell growth and lifespan while preserving cell-of-origin functionality. We initially determined the electrophysiological and morphological characteristics of conventional versus CRC-expanded non-CF HBE cells. On the basis of these findings,we then created six CF cell CRC populations,three from sequentially obtained CF lungs and three from F508 del homozygous donors previously obtained and cryopreserved using conventional culture methods. Growth curves were plotted,and cells were subcultured,without irradiated feeders plus Y,into air-liquid interface conditions in nonproprietary and proprietary Ultroser G-containing media and were allowed to differentiate. Ussing chamber studies were performed after treatment of F508 del homozygous CF cells with the CFTR modulator VX-809. Bronchial epithelial cells grew exponentially in feeders plus Y,dramatically surpassing the numbers of conventionally grown cells. Passage 5 and 10 CRC HBE cells formed confluent mucociliary air-liquid interface cultures. There were differences in cell morphology and current magnitude as a function of extended passage,but the effect of VX-809 in increasing CFTR function was significant in CRC-expanded F508 del HBE cells. Thus,CRC technology expands the supply of functional primary CF HBE cells for testing CFTR modulators in Ussing chambers. View Publication

Approaches to deplete persistent HIV infection are needed. We investigated the combined impact of the latency reversing agent vorinostat (VOR) and AGS-004,an autologous dendritic cell immunotherapeutic,on the HIV reservoir. HIV+,stably treated participants in whom resting CD4+ T cell-associated HIV RNA (rca-RNA) increased after VOR exposure ex vivo and in vivo received 4 doses of AGS-004 every 3 weeks,followed by VOR every 72 hours for 30 days,and then the cycle repeated. Change in VOR-responsive host gene expression,HIV-specific T cell responses,low-level HIV viremia,rca-RNA,and the frequency of resting CD4+ T-cell infection (RCI) was measured at baseline and after each cycle. No serious treatment-related adverse events were observed among five participants. As predicted,VOR-responsive host genes responded uniformly to VOR dosing. Following cycles of AGS-004 and VOR,rca-RNA decreased significantly in only two participants,with a significant decrease in SCA observed in one of these participants. However,unlike other cohorts dosed with AGS-004,no uniform increase in HIV-specific immune responses following vaccination was observed. Finally,no reproducible decline of RCI,defined as a decrease of {\textgreater}50{\%},was observed. AGS-004 and VOR were safe and well-tolerated,but no substantial impact on RCI was measured. In contrast to previous clinical data,AGS-004 did not induce HIV-specific immune responses greater than those measured at baseline. More efficacious antiviral immune interventions,perhaps paired with more effective latency reversal,must be developed to clear persistent HIV infection. View Publication

Transcriptional status determines the HIV replicative state in infected patients. However,the transcriptional mechanisms for proviral replication control remain unclear. In this study,we show that,apart from its function in HIV integration,LEDGF/p75 differentially regulates HIV transcription in latency and proviral reactivation. During latency,LEDGF/p75 suppresses proviral transcription via promoter-proximal pausing of RNA polymerase II (Pol II) by recruiting PAF1 complex to the provirus. Following latency reversal,MLL1 complex competitively displaces PAF1 from the provirus through casein kinase II (CKII)-dependent association with LEDGF/p75. Depleting or pharmacologically inhibiting CKII prevents PAF1 dissociation and abrogates the recruitment of both MLL1 and Super Elongation Complex (SEC) to the provirus,thereby impairing transcriptional reactivation for latency reversal. These findings,therefore,provide a mechanistic understanding of how LEDGF/p75 coordinates its distinct regulatory functions at different stages of the post-integrated HIV life cycles. Targeting these mechanisms may have a therapeutic potential to eradicate HIV infection. View Publication

Glioblastoma (GBM) is the most common and aggressive malignant tumor in adult brain. Even with the current standard therapy including surgical resection followed by postoperative radiotherapy and chemotherapy with temozolomide (Temo),GBM patients still have a poor median survival. Reprogramming of tumor cells into non-malignant cells might be a promising therapeutic strategy for malignant tumors,including GBM. Based on previous studies using small molecules to reprogram astrocytes into neuronal cells,here we further identified a FTT cocktail of three commonly used drugs (Fasudil,Tranilast,and Temo) to reprogram patient-derived GBM cells,either cultured in serum containing or serum-free medium,into neuronal like cells. FTT-treated GBM cells displayed a neuronal like morphology,expressed neuronal genes,exhibited neuronal electrophysiological properties,and showed attenuated malignancy. More importantly,FTT cocktail more significantly suppressed tumor growth and prolonged survival in GBM patient derived xenograft than Temo alone. Our study provided preclinical evidence that the neuronal reprogramming drug cocktail might be a promising strategy to improve the existing treatment for GBM. View Publication

Cyclosporine A (CsA) is a powerful immunosuppressant,but it is an ineffective stand-alone treatment for systemic lupus erythematosus (SLE) due to poor target tissue distribution and renal toxicity. We hypothesized that CD71 (transferrin receptor 1)-directed delivery of CsA to the lymphatic system would improve SLE outcomes in a murine model. We synthesized biodegradable,ligand-conjugated nanoparticles [P2Ns-gambogic acid (GA)] targeting CD71. GA conjugation substantially increased nanoparticle association with CD3+ or CD20+ lymphocytes and with intestinal lymphoid tissues. In orally dosed MRL-lpr mice,P2Ns-GA-encapsulated CsA increased lymphatic drug delivery 4- to 18-fold over the ligand-free formulation and a commercial CsA capsule,respectively. Improved lymphatic bioavailability of CsA was paralleled by normalization of anti-double-stranded DNA immunoglobulin G titer,plasma cytokines,and glomerulonephritis. Thus,this study demonstrates the translational potential of nanoparticles that enhance the targeting of lymphatic tissues,transforming CsA into a potent single therapeutic for SLE. View Publication

Activation-induced cytidine deaminase (AID) mediates immunoglobulin class switch DNA recombination (CSR) and somatic hypermutation (SHM),critical processes for maturation of the antibody response. Epigenetic factors,such as histone deacetylases (HDACs),would underpin B cell differentiation stage-specific AID expression. Here,we showed that NAD+-dependent class III HDAC sirtuin 1 (Sirt1) is highly expressed in resting B cells and down-regulated by stimuli inducing AID. B cell Sirt1 down-regulation,deprivation of NAD+ cofactor,or genetic Sirt1 deletion reduced deacetylation of Aicda promoter histones,Dnmt1,and nuclear factor-$\kappa$B (NF-$\kappa$B) p65 and increased AID expression. This promoted class-switched and hypermutated T-dependent and T-independent antibody responses or led to generation of autoantibodies. Genetic Sirt1 overexpression,Sirt1 boost by NAD+,or allosteric Sirt1 enhancement by SRT1720 repressed AID expression and CSR/SHM. By deacetylating histone and nonhistone proteins (Dnmt1 and NF-$\kappa$B p65),Sirt1 transduces metabolic cues into epigenetic changes to play an important B cell-intrinsic role in modulating antibody and autoantibody responses. View Publication

The Glioblastoma (GBM) immune microenvironment plays a critical role in tumor development,progression,and prognosis. A comprehensive understanding of the intricate milieu and its interactions remains unclear,and single-cell analysis is crucially needed. Leveraging mass cytometry (CyTOF),we analyzed immunocytes from 13 initial and three recurrent GBM samples and their matched peripheral blood mononuclear cells (pPBMCs). Using a panel of 30 markers,we provide a high-dimensional view of the complex GBM immune microenvironment. Hematoxylin and eosin staining and polychromatic immunofluorescence were used for verification of the key findings. In the initial and recurrent GBMs,glioma-associated microglia/macrophages (GAMs) constituted 59.05 and 27.87{\%} of the immunocytes,respectively; programmed cell death-ligand 1 (PD-L1),T cell immunoglobulin domain and mucin domain-3 (TIM-3),lymphocyte activation gene-3 (LAG-3),interleukin-10 (IL-10) and transforming growth factor-$\beta$ (TGF$\beta$) demonstrated different expression levels in the GAMs among the patients. GAMs could be subdivided into different subgroups with different phenotypes. Both the exhausted T cell and regulatory T (Treg) cell percentages were significantly higher in tumors than in pPBMCs. The natural killer (NK) cells that infiltrated into the tumor lesions expressed higher levels of CXC chemokine receptor 3 (CXCR3),as these cells expressed lower levels of interferon-$\gamma$ (IFN$\gamma$). The immune microenvironment in the initial and recurrent GBMs displayed similar suppressive changes. Our study confirmed that GAMs,as the dominant infiltrating immunocytes,present great inter- and intra-tumoral heterogeneity and that GAMs,increased exhausted T cells,infiltrating Tregs,and nonfunctional NK cells contribute to local immune suppressive characteristics. Recurrent GBMs share similar immune signatures with the initial GBMs except the proportion of GAMs decreases. View Publication

Here,we report on the results of a phase I/II trial (NCT00490529) for patients with mantle cell lymphoma who,having achieved remission after immunochemotherapy,were vaccinated with irradiated,CpG-activated tumor cells. Subsequently,vaccine-primed lymphocytes were collected and reinfused after a standard autologous stem cell transplantation (ASCT). The primary endpoint was detection of minimal residual disease (MRD) within 1 yr after ASCT at the previously validated threshold of ≥1 malignant cell per 10,000 leukocyte equivalents. Of 45 evaluable patients,40 (89{\%}) were found to be MRD negative,and the MRD-positive patients experienced early subsequent relapse. The vaccination induced antitumor CD8 T cell immune responses in 40{\%} of patients,and these were associated with favorable clinical outcomes. Patients with high tumor PD-L1 expression after in vitro exposure to CpG had inferior outcomes. Vaccination with CpG-stimulated autologous tumor cells followed by the adoptive transfer of vaccine-primed lymphocytes after ASCT is feasible and safe. View Publication

Toll-like receptor 8 (TLR-8) plays a role in the pathogenesis of autoimmune disorders and associated gastrointestinal symptoms that reduce quality of life of patients. Dietary interventions are becoming more accepted as mean to manage onset,progression,and treatment of a broad spectrum of inflammatory conditions. In this study,we assessed the impact of N-glycans derived from bovine lactoferrin (bLF) on the inhibition of TLR-8 activation. We investigated the effects of N-glycans in their native form,as well as in its partially demannosylated and partially desialylated form,on HEK293 cells expressing TLR-8,and in human monocyte-derived dendritic cells (MoDCs). We found that in HEK293 cells,N-glycans strongly inhibited the ssRNA40 induced TLR-8 activation but to a lesser extent the R848 induced TLR-8 activation. The impact was compared with a pharmaceutical agent,i.e.,chloroquine (CQN),that is clinically applied to antagonize endosomal TLR- activation. Inhibitory effects of the N-glycans were not influenced by the partially demannosylated or partially desialylated N-glycans. As the difference in charge of the N-glycans did not influence the inhibition capacity of TLR-8,it is possible that the inhibition mediated by the N-glycans is a result of a direct interaction with the receptor rather than a result of pH changes in the endosome. The inhibition of TLR-8 in MoDCs resulted in a significant decrease of IL-6 when cells were treated with the unmodified (0.5-fold,p {\textless} 0.0001),partially demannosylated (0.3-fold,p {\textless} 0.0001) and partially desialylated (0.4-fold,p {\textless} 0.0001) N-glycans. Furthermore,the partially demannosylated and partially desialylated N-glycans showed stronger inhibition of IL-6 production compared with the native N-glycans. This provides evidence that glycan composition plays a role in the immunomodulatory activity of the isolated N-glycans from bLF on MoDCs. Compared to CQN,the N-glycans are specific inhibitors of TLR-8 activation and of IL-6 production in MoDCs. Our findings demonstrate that isolated N-glycans from bLF have attenuating effects on TLR-8 induced immune activation in HEK293 cells and human MoDCs. The inhibitory capacity of N-glycans isolated from bLF onTLR-8 activation may become a food-based strategy to manage autoimmune,infections or other inflammatory disorders. View Publication

Mannose is a glucose-associated serum metabolite mainly released by the liver. Recent studies have shown several unexpected pleiotropic effects of mannose including increased regulatory T cells (Tregs),prevention of auto-immune disease and ability to reduce growth of human cancer cells. We have previously shown in large cohorts that elevated serum mannose levels are associated with future development of type 2 diabetes (T2D) and cardiovascular disease. However,potential direct effects of mannose on insulin sensitivity in vivo or in vitro are unknown. We here show that administration of mannose (0.1 g/kg BW twice daily) for one week in man did not elicit negative effects on meal-modified glucose tolerance,markers of inflammation or insulin levels. Tregs number and insulin signaling in human liver cells were unchanged. These data suggest that mannose is a marker,and not a mediator,of insulin resistance. To verify this,we examined serum mannose levels during long-term euglycemic hyperinsulinemic clamps in non-diabetic and T2D individuals. Mannose was reduced by insulin infusion in proportion to whole-body insulin sensitivity. Thus,mannose is a biomarker of insulin resistance which may be useful for the early identification of diabetic individuals with insulin resistance and increased risk of its complications. View Publication

The placenta and umbilical cord are pre-eminent candidate sources of mesenchymal stem cells (MSCs). However,placenta-derived MSCs (P-MSCs) showed greater proliferation capacity than umbilical cord-derived MSCs (UC-MSCs) in our study. We investigated the drivers of this proliferation difference and elucidated the mechanisms of proliferation regulation. Proteomic profiling and Gene Ontology (GO) functional enrichment were conducted to identify candidate proteins that may influence proliferation. Using lentiviral or small interfering RNA infection,we established overexpression and knockdown models and observed changes in cell proliferation to examine whether a relationship exists between the candidate proteins and proliferation capacity. Real-time quantitative polymerase chain reaction,western blot analysis,and immunofluorescence assays were conducted to elucidate the mechanisms underlying proliferation. Six candidate proteins were selected based on the results of proteomic profiling and GO functional enrichment. Through further validation,yes-associated protein 1 (YAP1) and $\beta$-catenin were confirmed to affect MSCs proliferation rates. YAP1 and $\beta$-catenin showed increased nuclear colocalization during cell expansion. YAP1 overexpression significantly enhanced proliferation capacity and upregulated the expression of both $\beta$-catenin and the transcriptional targets of Wnt signaling,CCND1,and c-MYC,whereas silencing $\beta$-catenin attenuated this influence. We found that YAP1 directly interacts with $\beta$-catenin in the nucleus to form a transcriptional YAP/$\beta$-catenin/TCF4 complex. Our study revealed that YAP1 and $\beta$-catenin caused the different proliferation capacities of P-MSCs and UC-MSCs. Mechanism analysis showed that YAP1 stabilized the nuclear $\beta$-catenin protein,and also triggered the Wnt/$\beta$-catenin pathway,promoting proliferation. View Publication