技术资料

The clinical success of stem cell therapy for myocardial repair hinges on a better understanding of cardiac fate mechanisms. We have identified small molecules involved in cardiac fate by screening a chemical library for activators of the signature gene Nkx2.5,using a luciferase knockin bacterial artificial chromosome (BAC) in mouse P19CL6 pluripotent stem cells. We describe a family of sulfonyl-hydrazone (Shz) small molecules that can trigger cardiac mRNA and protein expression in a variety of embryonic and adult stem/progenitor cells,including human mobilized peripheral blood mononuclear cells (M-PBMCs). Small-molecule-enhanced M-PBMCs engrafted into the rat heart in proximity to an experimental injury improved cardiac function better than control cells. Recovery of cardiac function correlated with persistence of viable human cells,expressing human-specific cardiac mRNAs and proteins. Shz small molecules are promising starting points for drugs to promote myocardial repair/regeneration by activating cardiac differentiation in M-PBMCs. View Publication

BACKGROUND: Hair bulge progenitor cells (HBPCs) are multipotent stem cells derived from the bulge region of mice vibrissal hairs. The purified HBPCs express CD34,K15 and K14 surface markers. It has been reported that HBPCs could be readily induced to transdifferentiate into adipocytes and osteocytes. However,the ability of HBPCs to transdifferentiate into cardiomyocytes has not yet been investigated. METHODOLOGY/PRINCIPAL FINDINGS: The cardiomyogenic potential of HBPCs was investigated using a small cell-permeable molecule called Cardiogenol C. We established that Cardiogenol C could induce HBPCs to express transcription factors GATA4,Nkx2.5 and Tbx5,which are early specific markers for pre-cardiomyogenic cells. In prolonged cultures,the Cardiogenol C-treated HBPCs can also express muscle proteins,cardiac-specific troponin I and sarcomeric myosin heavy chain. However,we did not observe the ability of these cells to functionally contract. Hence,we called these cells cardiomyocyte-like cells rather than cardiomyocytes. We tried to remedy this deficiency by pre-treating HBPCs with Valproic acid first before exposing them to Cardiogenol C. This pretreatment inhibited,rather than improved,the effectiveness of Cardiogenol C in reprogramming the HBPCs. We used comparative proteomics to determine how Cardiogenol C worked by identifying proteins that were differentially expressed. We identified proteins that were involved in promoting cell differentiation,cardiomyocyte development and for the normal function of striated muscles. From those differentially expressed proteins,we further propose that Cardiogenol C might exert its effect by activating the Wnt signaling pathway through the suppression of Kremen1. In addition,by up-regulating the expression of chromatin remodeling proteins,SIK1 and Smarce1 would initiate cardiac differentiation. CONCLUSIONS/SIGNIFICANCE: In conclusion,our CD34+/K15+ HBPCs could be induced to transdifferentiate into cardiomyocyte-like cells using a small molecule called Cardiogenol C. The process involves activation of the Wnt signaling pathway and altered expression of several key chromatin remodeling proteins. The finding is clinically significant as HBPCs offer a readily accessible and autologous source of progenitor cells for cell-based therapy of heart disease,which is one of major killers in developed countries. View Publication

A comprehensive understanding of the cardio-spleen-bone marrow immune cell axis is essential for elucidating the alterations occurring during the pathogenesis of diabetes mellitus (DM). This study investigates the dynamics of immune cell kinetics in DM after myocardial infarction (MI) over time. MI was induced in diabetic and healthy control groups using C57BL/N6 mice,with sacrifices occurring at days 1,3,7,and 28 post-MI to collect heart,peripheral blood (PB),spleen,and bone marrow (BM) samples. Cell suspensions from each organ were isolated and analyzed via flow cytometry. Additionally,the endothelial progenitor cell-colony-forming assay (EPC-CFA) was performed using mononuclear cells derived from BM,PB,and the spleen. The results indicated that,despite normal production in BM and the spleen,CD45+ cells were lower in the PB of DM mice at days 1 to 3. Further analysis revealed a reduction in total and pro-inflammatory neutrophils (N1s) in PB at days 1 to 3 and in the spleen at days 3 to 7 in DM mice,suggesting that DM-induced alterations in splenic neutrophils fail to meet the demand in PB and ischemic tissues. Infiltrating macrophages (total,M1,M2) were reduced at day 3 in the DM-ischemic heart,with total and M1 (days 1–3) and M2 (days 3–7) macrophages being significantly decreased in DM-PB compared to controls,indicating impaired macrophage recruitment and polarization in DM. Myeloid dendritic cells (mDCs) in the heart were higher from days 1 to 7,which corresponded with the enhanced recruitment of CD8+ cells from days 1 to 28 in the DM-infarcted myocardium. Total CD4+ cells decreased in DM-PB at days 1 to 3,suggesting a delayed adaptive immune response to MI. B cells were reduced in PB at days 1 to 3,in myocardium at day 3,and in the spleen at day 7,indicating compromised mobilization from BM. EPC-CFA results showed a marked decrease in definitive EPC colonies in the spleen and BM from days 1 to 28 in DM mice compared to controls in vitro,highlighting that DM severely impairs EPC colony-forming activity by limiting the differentiation of EPCs from primitive to definitive forms. Taking together,this study underscores significant disruptions in the cardio-spleen-bone marrow immune cell axis following MI in DM,revealing delayed innate and adaptive immune responses along with impaired EPC differentiation. View Publication

SummarymRNA-based in vivo chimeric antigen receptor (CAR)-T cell engineering offers advantages over ex vivo therapies,including streamlined manufacturing and transient expression. However,current delivery methods require antibody-modified vehicles with manufacturing challenges. In this study,inspired by cardiolipin,we identify cardiolipin-like di-phosphoramide lipids that improve T cell transfection without targeting ligands,both in vitro and in vivo. The T cell-favored tropism is likely due to the lipid’s packing,shape,and rigidity. Encapsulating circular RNA further prolongs mRNA expression in the spleen and T cells. Using PL40 lipid nanoparticles,we deliver mRNA encoding a CAR targeting the senolytic and inflammatory antigen urokinase-type plasminogen activator receptor (uPAR),alleviating uPAR-related liver fibrosis and rheumatoid arthritis (RA). Single-cell sequencing in humans confirms uPAR’s relevance to senescence and inflammation in RA. To facilitate clinical translation,we screen and humanize single-chain variable fragments (scFvs) against uPAR,establishing a PL40 mRNA-encoded humanized uPAR CAR with potential for treating aging-inflamed disorders. Graphical abstract Highlights•Cardiolipin-mimic phosphoramide (CAMP) LNPs transfect T cells without antibody modification•Circular mRNA prolongs mRNA expression•Senolytic in vivo CAR-T treats inflamm-aging disease (liver fibrosis and rheumatoid arthritis)•Develop humanized anti-human uPAR scFv Zhang et al. develop Cardiolipin-mimic phosphoramide (CAMP) lipids,which enable T cell transfection without antibody modification. Using CAMP-based LNPs,they generate senolytic CAR-T cells in vivo to target inflamm-aging diseases. Additionally,they employ circular mRNA to prolong transgene expression. The authors also engineer a humanized anti-human uPAR scFv for clinically relevant applications. View Publication

More than 10 years after their first isolation,human embryonic stem cells are finally 'coming of age' in research and biotechnology applications as protocols for their differentiation and undifferentiated expansion in culture become robust and scalable,and validated commercial reagents become available. Production of human cardiomyocytes is now feasible on a daily basis for many laboratories with tissue culture expertise. An additional recent surge of interest resulting from the first production of human iPSCs (induced pluripotent stem cells) from somatic cells of patients now makes these technologies of even greater importance since it is likely that (genetic) cardiac disease phenotypes can be captured in the cardiac derivatives of these cells. Although cell therapy based on replacing cardiomyocytes lost or dysfunctional owing to cardiac disease are probably as far away as ever,biotechnology and pharmaceutical applications in safety pharmacology and drug discovery will probably impact this clinical area in the very near future. In the present paper,we review the cutting edge of this exciting area of translational research. View Publication

SummaryNeonatal mouse hearts have transient renewal capacity,which is lost in juvenile and adult stages. In neonatal mouse hearts,myocardial infarction (MI) causes an initial loss of cardiomyocytes. However,it is unclear which type of regulated cell death (RCD) occurs in stressed cardiomyocytes. In the current studies,we induced MI in neonatal and juvenile mouse hearts and showed that ischemic cardiomyocytes primarily undergo ferroptosis,a non-apoptotic and iron-dependent form of RCD. We demonstrated that cardiac fibroblasts (CFs) protect cardiomyocytes from ferroptosis through paracrine effects and direct cell-cell interaction. CFs show strong resistance to ferroptosis due to high ferritin expression. The fibrogenic activity of CFs,typically considered detrimental to heart function,is negatively regulated by paired-like homeodomain 2 (Pitx2) signaling from cardiomyocytes. In addition,Pitx2 prevents ferroptosis in cardiomyocytes by regulating ferroptotic genes. Understanding the regulatory mechanisms of cardiomyocyte survival and death can identify potentially translatable therapeutic strategies for MI. Graphical abstract Highlights•Neonatal and juvenile mouse cardiomyocytes mainly undergo ferroptosis after MI•Cardiac fibroblasts protect cardiomyocytes through paracrine effect•Cardiac fibroblasts interact with cardiomyocytes to share iron burden•Pitx2 pathway protects cardiomyocytes from ferroptosis and controls fibrosis Cardiovascular medicine; Physiology; Cell biology View Publication

Stem cells derived from pre-implantation human embryos or from somatic cells by reprogramming are pluripotent and self-renew indefinitely in culture. Pluripotent stem cells are unique in being able to differentiate to any cell type of the human body. Differentiation towards the cardiac lineage has attracted significant attention,initially with a strong focus on regenerative medicine. Although an important research area,the heart has proven challenging to repair by cardiomyocyte replacement. However,the ability to reprogramme adult cells to pluripotent stem cells and genetically manipulate stem cells presented opportunities to develop models of human disease. The availability of human cardiomyocytes from stem cell sources is expected to accelerate the discovery of cardiac drugs and safety pharmacology by offering more clinically relevant human culture models than presently available. Here we review the state-of-the-art using stem cell-derived human cardiomyocytes in drug discovery,drug safety pharmacology,and regenerative medicine. View Publication

Currently immunomodulatory compounds are under investigation for use in patients with cardiovascular disease,caused by atherosclerosis. These trials,using recurrent cardiovascular events as endpoint,require enrollment of large patient groups. We investigated the effect of key risk factors for atherosclerosis development,ageing and smoking,on the immune system,with the objective to identify biomarkers differentiating between human populations,and potentially serving as endpoints for future phase 1B trials with immunomodulatory compounds. Blood was collected from young healthy volunteers (aged 18-25 years,n=30),young smokers (18-25 years,n=20),elderly healthy volunteers (>60 years,n=20),heavy smokers (>45 years,15 packyears,n=11) and patients with stable coronary artery disease (CAD) (>60 years,n=27). Circulating immune cell subsets were characterized by flow cytometry,and collected plasma was evaluated by proteomics (Olink). Clear ageing effects were observed,mostly illustrated by a lower level in CD8+ and na{\{i}}ve CD4+ and CD8+ T cells with an increase in CD4+ and CD8+ effector memory T cells in elderly healthy volunteers compared to young healthy volunteers. Heavy smokers showed a more inflammatory cellular phenotype especially a shift in Th1/Th2 ratio: higher Th1 and lower Th2 percentages compared to young healthy volunteers. A significant decrease in circulating atheroprotective oxLDL-specific IgM was found in patients with CAD compared to young healthy volunteers. Elevated pro-inflammatory and chemotactic proteins TREM1 and CCL11 were observed in elderly volunteers compared to young volunteers. In addition heavy smokers had an increase in pro-inflammatory cytokine IL-6 and lysosomal protein LAMP3. These data show that ageing and smoking are associated with an inflammatory immunophenotype and that heavy smokers or aged individuals may serve as potential populations for future clinical trials investigating immunomodulatory drugs targeted for cardiovascular disease." View Publication

Background Exposure to fine airborne particulate matter ( PM 2.5) induces quantitative and qualitative defects in bone marrow-derived endothelial progenitor cells of mice,and similar outcomes in humans may contribute to vascular dysfunction and the cardiovascular morbidity and mortality associated with PM 2.5 exposure. Nevertheless,mechanisms underlying the pervasive effects of PM 2.5 are unclear and effective interventional strategies to mitigate against PM 2.5 toxicity are lacking. Furthermore,whether PM 2.5 exposure affects other types of bone marrow stem cells leading to additional hematological or immunological dysfunction is not clear. Methods and Results Mice given normal drinking water or that supplemented with carnosine,a naturally occurring,nucleophilic di-peptide that binds reactive aldehydes,were exposed to filtered air or concentrated ambient particles. Mice drinking normal water and exposed to concentrated ambient particles demonstrated a depletion of bone marrow hematopoietic stem cells but no change in mesenchymal stem cells. However,HSC depletion was significantly attenuated when the mice were placed on drinking water containing carnosine. Carnosine supplementation also increased the levels of carnosine-propanal conjugates in the urine of CAPs-exposed mice and prevented the concentrated ambient particles-induced dysfunction of endothelial progenitor cells as assessed by in vitro and in vivo assays. Conclusions These results suggest that exposure to PM 2.5 has pervasive effects on different bone marrow stem cell populations and that PM 2.5-induced hematopoietic stem cells depletion,endothelial progenitor cell dysfunction,and defects in vascular repair can be mitigated by excess carnosine. Carnosine supplementation may be a viable approach for preventing PM 2.5-induced immune dysfunction and cardiovascular injury in humans. View Publication

ABSTRACTCell therapy based on chimeric antigen receptor (CAR) T cells has represented a revolutionary new approach for treating tumors,especially hematological diseases. Complete remission rates (CRR) > 80%–97% and 50%–90% overall response rates (ORR) have been achieved with a treatment based on CAR‐T cells in patients with malignant B‐cell tumors that have relapsed or are refractory to previous treatments. Toxicity remains the major problem. Most patients treated with CAR‐T cells develop high‐grade cytokine release syndrome (CRS) and immune effector cell‐associated neurotoxicity syndrome (ICANS). However,the unprecedentedly high CRR and ORR have led to the approval of six CAR‐T cell therapeutics by the Food and Drug Administration (FDA) and the European Medicines Agency (EMA),prompting researchers to improve existing products and develop new ones. By now,around 1000 clinical trials based on CAR‐T cells are registered at ClinicalTrials.gov: 82% are for hematological diseases,while the remaining 16% are for solid tumors. As a result of this increased research,an enormous amount of conflicting information has been accumulated in the literature,and each group follows its manufacturing protocols and performs specific in vitro testing. This review aimed to combine and compare clinical and preclinical information,highlighting the most used protocols to provide a comprehensive overview of the in vitro world of CAR‐T cells,from manufacturing to their characterization. The focus is on all steps of the CAR‐T cell manufacturing process,from the collection of patient or donor blood to the enrichment of T cells,their activation with anti‐CD3/CD28 beads,interleukin‐2 (IL‐2) or IL‐7 and IL‐15 (induction of a more functional memory phenotype),and their transfection (viral or non‐viral methods). Automation is crucial for ensuring a standardized final product. View Publication

The identification of the trans-acting factors and cis-regulatory modules that are involved in human pluripotent stem cell (hPSC) maintenance and differentiation is necessary to dissect the operating regulatory networks in these processes and thereby identify nodes where signal input will direct desired cell fate decisions in vitro or in vivo. To deconvolute these networks,we established a method to influence the differentiation state of hPSCs with a CRISPR-associated catalytically inactive dCas9 fused to an effector domain. In human embryonic stem cells,we find that the dCas9 effectors can exert positive or negative regulation on the expression of developmentally relevant genes,which can influence cell differentiation status when impinging on a key node in the regulatory network that governs the cell state. This system provides a platform for the interrogation of the underlying regulators governing specific differentiation decisions,which can then be employed to direct cellular differentiation down desired pathways. View Publication

Clinical studies have shown that Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) is associated with aggressive periodontitis and can potentially trigger or exacerbate rheumatoid arthritis (RA). However,the mechanism is poorly understood. Here,we show that systemic infection with A. actinomycetemcomitans triggers the progression of arthritis in mice anti-collagen antibody-induced arthritis (CAIA) model following IL-1β secretion and cell infiltration in paws in a manner that is dependent on caspase-11-mediated inflammasome activation in macrophages. The administration of polymyxin B (PMB),chloroquine,and anti-CD11b antibody suppressed inflammasome activation in macrophages and arthritis in mice,suggesting that the recognition of lipopolysaccharide (LPS) in the cytosol after bacterial degradation by lysosomes and invasion via CD11b are needed to trigger arthritis following inflammasome activation in macrophages. These data reveal that the inhibition of caspase-11-mediated inflammasome activation potentiates aggravation of RA induced by infection with A. actinomycetemcomitans. This work highlights how RA can be progressed by inflammasome activation as a result of periodontitis-associated bacterial infection and discusses the mechanism of inflammasome activation in response to infection with A. actinomycetemcomitans. View Publication