技术资料

In recent years,Raman spectroscopy has garnered growing interest in the field of biomedical research. It offers a non-invasive and label-free approach to defining the molecular fingerprint of immune cells. We utilized Raman spectroscopy on optically trapped immune cells to investigate their molecular compositions. While numerous immune cell types have been studied in the past,the characterization of living human CD3/CD28-stimulated T cell subsets remains incomplete. In this study,we demonstrate the capability of Raman spectroscopy to readily distinguish between naïve and stimulated CD4 and CD8 cells. Additionally,we compared these cells with monocytes and discovered remarkable similarities between stimulated T cells and monocytes. This paper contributes to expanding our knowledge of Raman spectroscopy of immune cells and serves as a launching point for future clinical applications. View Publication

Paulownin,a natural compound derived from Paulownia tomentosa wood,exhibits various physiological functions,including anti-bacterial and anti-fungal effects. However,the impact of paulownin on natural killer (NK) cell immune activity remains largely unknown. In this study,we investigated the effect of paulownin on NK cell activity both in vitro and in vivo,and explored its potential mechanisms. NK-92 cells were used for in vitro experiments and a BALB/c mouse model with B16F10 cells injected subcutaneously were used for in vivo anti-tumor analysis. We found that paulownin enhanced the cytolytic activity of NK-92 cells against leukemia,human colon,and human lung cancer cell lines. Paulownin treatment increased the expression of the degranulation marker protein CD107a and cytolytic granules,including granzyme B and perforin in NK-92 cells. Moreover,these enhancements of cytotoxicity and the expression of cytolytic granules induced by paulownin were also observed in human primary NK cells. Signaling studies showed that paulownin promoted the phosphorylation of JNK. The increased perforin expression and elevated cytotoxic activity induced by paulownin were effectively inhibited by pre-treatment with a JNK inhibitor. In vivo studies demonstrated that the administration of paulownin suppressed the growth of B16F10 melanoma cells allografted into mice. Paulownin administration promoted the activation of NK cells in the spleen of mice,resulting in enhanced cytotoxicity against YAC-1 cells. Moreover,the anti-tumor effects of paulownin were reduced upon the depletion of NK cells. Therefore,these results suggest that paulownin enhances NK cell cytotoxicity by activating the JNK signaling pathway and provide significant implications for developing new strategies for cancer immunotherapy. View Publication

Automation and quality control (QC) are critical in manufacturing safe and effective cell and gene therapy products. However,current QC methods,reliant on molecular staining,pose difficulty in in-line testing and can increase manufacturing costs. Here we demonstrate the potential of using label-free ghost cytometry (LF-GC),a machine learning-driven,multidimensional,high-content,and high-throughput flow cytometry approach,in various stages of the cell therapy manufacturing processes. LF-GC accurately quantified cell count and viability of human peripheral blood mononuclear cells (PBMCs) and identified non-apoptotic live cells and early apoptotic/dead cells in PBMCs (ROC-AUC: area under receiver operating characteristic curve = 0.975),T cells and non-T cells in white blood cells (ROC-AUC = 0.969),activated T cells and quiescent T cells in PBMCs (ROC-AUC = 0.990),and particulate impurities in PBMCs (ROC-AUC ≧ 0.998). The results support that LF-GC is a non-destructive label-free cell analytical method that can be used to monitor cell numbers,assess viability,identify specific cell subsets or phenotypic states,and remove impurities during cell therapy manufacturing. Thus,LF-GC holds the potential to enable full automation in the manufacturing of cell therapy products with reduced cost and increased efficiency. Subject terms: Biotechnology,Cell biology,Immunology,Biomedical engineering View Publication

Down syndrome predisposes individuals to haematological abnormalities,such as increased number of erythrocytes and leukaemia in a process that is initiated before birth and is not entirely understood 1 – 3 . Here,to understand dysregulated haematopoiesis in Down syndrome,we integrated single-cell transcriptomics of over 1.1 million cells with chromatin accessibility and spatial transcriptomics datasets using human fetal liver and bone marrow samples from 3 fetuses with disomy and 15 fetuses with trisomy. We found that differences in gene expression in Down syndrome were dependent on both cell type and environment. Furthermore,we found multiple lines of evidence that haematopoietic stem cells (HSCs) in Down syndrome are ‘primed’ to differentiate. We subsequently established a Down syndrome-specific map linking non-coding elements to genes in disomic and trisomic HSCs using 10X multiome data. By integrating this map with genetic variants associated with blood cell counts,we discovered that trisomy restructured regulatory interactions to dysregulate enhancer activity and gene expression critical to erythroid lineage differentiation. Furthermore,as mutations in Down syndrome display a signature of oxidative stress 4,5,we validated both increased mitochondrial mass and oxidative stress in Down syndrome,and observed that these mutations preferentially fell into regulatory regions of expressed genes in HSCs. Together,our single-cell,multi-omic resource provides a high-resolution molecular map of fetal haematopoiesis in Down syndrome and indicates significant regulatory restructuring giving rise to co-occurring haematological conditions. Subject terms: Haematopoietic stem cells,Leukaemia,Haematopoiesis,Haematological diseases,Aneuploidy View Publication

Stimulating erythropoiesis is essential in the treatment of various types of anemia. Sheng Xue Ning (SXN) is commonly used in China as an iron supplement to treat iron deficiency anemia,renal anemia,and anemia in pregnancy. This research reports a novel effect of SXN in enhancing the proliferation of hematopoietic stem/progenitor cell (HSPC) to promote erythropoiesis in the bone marrow,which is distinct from conventional iron supplements that primarily aid in the maturation of red blood cells. Employing a model of hematopoietic dysfunction induced by X-ray exposure,we evaluated the efficacy of SXN in restoring hematopoietic function. SXN significantly promoted the recovery of peripheral erythroid cells and enhanced the proliferation and differentiation of Lin − /c-KIT + /Sca-1 + HSPC in mice exposed to X-ray irradiation. Our results showed that SXN elevated the expression of stem cell factor (SCF) and activated the SCF/c-KIT/PI3K/AKT signaling pathway,facilitating the proliferation and differentiation of HSPC. In vitro,SXN markedly enhanced the proliferation of bone marrow nucleated cell (BMNC) and the colony-forming capacity of BFU-E,CFU-E,and CFU-GM,while also elevating the expression of proteins involved in the SCF/c-KIT/PI3K/AKT pathway in BMNC. Additionally,SXN enhanced the proliferation and differentiation of mesenchymal stem cell (MSC) and increased SCF secretion. In conclusion,SXN demonstrates the capacity to enhance erythropoiesis by upregulating SCF expression,thereby promoting HSPC proliferation and differentiation via the SCF/c-KIT/PI3K/AKT pathway. SXN may offer a new strategy for improving the activity of HSPC and promoting erythropoiesis in the treatment of hematopoiesis disorders. View Publication

Mutation of tet methylcytosine dioxygenase 2 (encoded by TET2 ) drives myeloid malignancy initiation and progression 1 – 3 . TET2 deficiency is known to cause a globally opened chromatin state and activation of genes contributing to aberrant haematopoietic stem cell self-renewal 4,5 . However,the open chromatin observed in TET2-deficient mouse embryonic stem cells,leukaemic cells and haematopoietic stem and progenitor cells 5 is inconsistent with the designated role of DNA 5-methylcytosine oxidation of TET2. Here we show that chromatin-associated retrotransposon RNA 5-methylcytosine (m 5 C) can be recognized by the methyl-CpG-binding-domain protein MBD6,which guides deubiquitination of nearby monoubiquitinated Lys119 of histone H2A (H2AK119ub) to promote an open chromatin state. TET2 oxidizes m 5 C and antagonizes this MBD6-dependent H2AK119ub deubiquitination. TET2 depletion thereby leads to globally decreased H2AK119ub,more open chromatin and increased transcription in stem cells. TET2- mutant human leukaemia becomes dependent on this gene activation pathway,with MBD6 depletion selectively blocking proliferation of TET2 -mutant leukaemic cells and largely reversing the haematopoiesis defects caused by Tet2 loss in mouse models. Together,our findings reveal a chromatin regulation pathway by TET2 through retrotransposon RNA m 5 C oxidation and identify the downstream MBD6 protein as a feasible target for developing therapies specific against TET2 mutant malignancies. Subject terms: Molecular biology,Chromatin View Publication

In calcium imaging studies,Ca 2+ transients are commonly interpreted as neuronal action potentials (APs). However,our findings demonstrate that robust optical Ca 2+ transients primarily stem from complex “AP-Plateaus”,while simple APs lacking underlying depolarization envelopes produce much weaker photonic signatures. Under challenging in vivo conditions,these “AP-Plateaus” are likely to surpass noise levels,thus dominating the Ca 2+ recordings. In spontaneously active neuronal culture,optical Ca 2+ transients (OGB1-AM,GCaMP6f) exhibited approximately tenfold greater amplitude and twofold longer half-width compared to optical voltage transients (ArcLightD). The amplitude of the ArcLightD signal exhibited a strong correlation with the duration of the underlying membrane depolarization,and a weaker correlation with the presence of a fast sodium AP. Specifically,ArcLightD exhibited robust responsiveness to the slow “foot” but not the fast “trunk” of the neuronal AP. Particularly potent stimulators of optical signals in both Ca 2+ and voltage imaging modalities were APs combined with plateau potentials (AP-Plateaus),resembling dendritic Ca 2+ spikes or “UP states” in pyramidal neurons. Interestingly,even the spikeless plateaus (amplitude > 10 mV,duration > 200 ms) could generate conspicuous Ca 2+ optical signals in neurons. Therefore,in certain circumstances,Ca 2+ transients should not be interpreted solely as indicators of neuronal AP firing. Subject terms: Biological techniques,Biophysics,Neuroscience,Physiology View Publication

Fibronectin (FN) is an extracellular matrix glycoprotein essential for the development and function of major vertebrate organ systems. Mutations in FN result in an autosomal dominant skeletal dysplasia termed corner fracture-type spondylometaphyseal dysplasia (SMDCF). The precise pathomechanisms through which mutant FN induces impaired skeletal development remain elusive. Here,we have generated patient-derived induced pluripotent stem cells as a cell culture model for SMDCF to investigate the consequences of FN mutations on mesenchymal stem cells (MSCs) and their differentiation into cartilage-producing chondrocytes. In line with our previous data,FN mutations disrupted protein secretion from MSCs,causing a notable increase in intracellular FN and a significant decrease in extracellular FN levels. Analyses of plasma samples from SMDCF patients also showed reduced FN in circulation. FN and endoplasmic reticulum (ER) protein folding chaperones (BIP,HSP47) accumulated in MSCs within ribosome-covered cytosolic vesicles that emerged from the ER. Massive amounts of these vesicles were not cleared from the cytosol,and a smaller subset showed the presence of lysosomal markers. The accumulation of intracellular FN and ER proteins elevated cellular stress markers and altered mitochondrial structure. Bulk RNA sequencing revealed a specific transcriptomic dysregulation of the patient-derived cells relative to controls. Analysis of MSC differentiation into chondrocytes showed impaired mesenchymal condensation,reduced chondrogenic markers,and compromised cell proliferation in mutant cells. Moreover,FN mutant cells exhibited significantly lower transforming growth factor beta-1 (TGFβ1) expression,crucial for mesenchymal condensation. Exogenous FN or TGFβ1 supplementation effectively improved the MSC condensation and promoted chondrogenesis in FN mutant cells. These findings demonstrate the cellular consequences of FN mutations in SMDCF and explain the molecular pathways involved in the associated altered chondrogenesis. The online version contains supplementary material available at 10.1007/s00018-024-05444-4. View Publication

Human pluripotent stem cells (hPSCs) have the potential to differentiate into various cell types,including pancreatic insulin-producing β cells,which are crucial for developing therapies for diabetes. However,current methods for directing hPSC differentiation towards pancreatic β-like cells are often inefficient and produce cells that do not fully resemble the native counterparts. Here,we report that highly selective tankyrase inhibitors,such as WIKI4,significantly enhances pancreatic differentiation from hPSCs. Our results show that WIKI4 promotes the formation of pancreatic progenitors that give rise to islet-like cells with improved β-like cell frequencies and glucose responsiveness compared to our standard cultures. These findings not only advance our understanding of pancreatic development,but also provide a promising new tool for generating pancreatic cells for research and potential therapeutic applications. Subject terms: Stem-cell differentiation,Organogenesis,Type 1 diabetes View Publication

CRISPR-based genome editing of pseudogene-associated disorders,such as p47 phox -deficient chronic granulomatous disease (p47 CGD),is challenged by chromosomal rearrangements due to presence of multiple targets. We report that interactions between highly homologous sequences that are localized on the same chromosome contribute substantially to post-editing chromosomal rearrangements. We successfully employed editing approaches at the NCF1 gene and its pseudogenes,NCF1B and NCF1C,in a human cell line model of p47 CGD and in patient-derived human hematopoietic stem and progenitor cells. Upon genetic engineering,a droplet digital PCR-based method identified cells with altered copy numbers,spanning megabases from the edited loci. We attributed the high aberration frequency to the interaction between repetitive sequences and their predisposition to recombination events. Our findings emphasize the need for careful evaluation of the target-specific genomic context,such as the presence of homologous regions,whose instability can constitute a risk factor for chromosomal rearrangements upon genome editing. Subject terms: CRISPR-Cas9 genome editing,Targeted gene repair,Haematopoietic stem cells View Publication

Despite significant progress in the prognosis of pediatric T-cell acute lymphoblastic leukemia (T-ALL) in recent decades,a notable portion of children still confronts challenges such as treatment resistance and recurrence,leading to limited options and a poor prognosis. LIM domain-binding protein 1 (LDB1) has been confirmed to exert a crucial role in various physiological and pathological processes. In our research,we aim to elucidate the underlying function and mechanisms of LDB1 within the background of T-ALL. Employing short hairpin RNA (shRNA) techniques,we delineated the functional impact of LDB1 in T-ALL cell lines. Through the application of RNA-Seq,CUT&Tag,and immunoprecipitation assays,we scrutinized master transcription factors cooperating with LDB1 and identified downstream targets under LDB1 regulation. LDB1 emerges as a critical transcription factor co-activator in cell lines derived from T-ALL. It primarily collaborates with master transcription factors (ERG,ETV6,IRF1) to cooperatively regulate the transcription of downstream target genes. Both in vitro and in vivo experiments affirm the essential fuction of LDB1 in the proliferation and survival of cell lines derived from T-ALL,with MYB identified as a significant downstream target of LDB1. To sum up,our research establishes the pivotal fuction of LDB1 in the tumorigenesis and progression of T-ALL cell lines. Mechanistic insights reveal that LDB1 cooperates with ERG,ETV6,and IRF1 to modulate the expression of downstream effector genes. Furthermore,LDB1 controls MYB through remote enhancer modulation,providing valuable mechanistic insights into its involvement in the progression of T-ALL. The online version contains supplementary material available at 10.1186/s13046-024-03199-1. View Publication

CD19CAR-T cell therapy demonstrated promising outcomes in relapsed/refractory B-cell malignancies. Nonetheless,the limited T-cell function and ineffective T-cell apheresis for therapeutic purposes are still concern in heavily pretreated patients. We investigated the feasibility of generating hematopoietic stem cell-derived T lymphocytes (HSC-T) for cancer immunotherapy. The patients’ autologous peripheral blood HSCs were enriched for CD34 + and CD3 + cells. The CD34 + cells were then cultured following three steps of lymphoid progenitor differentiation,T-cell differentiation,and T-cell maturation processes. HSC-T cells were successfully generated with robust fold expansion of 3735 times. After lymphoid progenitor differentiation,CD5 + and CD7 + cells remarkably increased (65–84 %) while CD34 + cells consequentially declined. The mature CD3 + cells were detected up to 40 % and 90 % on days 42 and 52,respectively. The majority of HSC-T population was naïve phenotype compared to CD3-T cells (73 % vs 34 %) and CD8:CD4 ratio was 2:1. The higher level of cytokine and cytotoxic granule secretion in HSC-T was observed after activation. HSC-T cells were assessed for clinical application and found that CD19CAR-transduced HSC-T cells demonstrated higher cytokine secretion and a trend of superior cytotoxicity against CD19 + target cells compared to control CAR-T cells. A chronic antigen stimulation assay revealed similar T-cell proliferation,stemness,and exhaustion phenotypes among CAR-T cell types. In conclusions,autologous HSC-T was feasible to generate with preserved T-cell efficacy. The HSC-T cells are potentially utilized as an alternative option for cellular immunotherapy. View Publication