技术资料

Acute myeloid leukemia (AML) is primarily driven by leukemic stem cells (LSCs),the main cause of relapse and therapy resistance. Here,we discover that LSCs are predominantly small and mechanically soft. These mechanical properties enable their selective isolation using microfluidic chips. Single-cell RNA-sequencing of primary human AML bone marrow identifies enrichment of LSCs within the FSClow ALDH1A1+ subpopulation,which exhibits long-term stemness in functional assays. Notably,inhibiting ALDH1A1 in these cells promotes F-actin polymerization and increases cellular stiffness,reducing their stemness while enhancing their susceptibility to natural killer (NK) cell-mediated cytotoxicity. In AML patient-derived xenograft models,the combination of ALDH1A1 inhibition with NK cell therapy markedly suppresses leukemia progression. These findings suggest that targeting the mechanical properties of LSC offers a promising strategy to overcome AML treatment resistance,providing insights into stem cell mechanobiology and paving the way for combining targeted therapies with immunotherapy to improve clinical outcomes. Leukemic stem cells (LSCs) drive relapse and therapy resistance in acute myeloid leukemia (AML). Here,the authors show that increasing the stiffness of LSCs reduces their stemness and enhances their susceptibility to natural killer cell-mediated immunotherapy in AML. View Publication

Background: Acute Lung Injury (ALI) and its most severe form,Acute Respiratory Distress Syndrome (ARDS),are critical pulmonary conditions characterized by life-threatening acute hypoxic respiratory failure,affecting over three million individuals globally each year. ALI involves alveolar inflammation and disruption of the alveolar-capillary barrier,primarily driven by neutrophil infiltration and the release of inflammatory mediators. In our previous study using a lipopolysaccharide (LPS)-induced mouse model of ALI,we demonstrated that C6,a peptide inhibitor of voltage-gated proton channels (Hv1),ameliorates lung injury,identifying Hv1 as a potential therapeutic target. However,(i) whether the anti-inflammatory effects of C6 are translatable to a clinically relevant live bacterial infection model,and (ii) the molecular mechanisms underlying these anti-inflammatory effects,remain unknown,and are a crucial next step towards targeted rational drug development. Methods: To induce ALI,we used an intratracheal Pseudomonas aeruginosa infection model,a gram-negative bacterium relevant in ventilated and immunocompromised patients. A separate group of infected mice also received intravenous treatment with C6 (4 mg/kg). Lung injury severity was evaluated using histopathological analysis. Bronchoalveolar lavage (BAL) fluid was collected to quantify neutrophil infiltration and proinflammatory cytokines concentrations. In addition,reactive oxygen species (ROS) production and intracellular calcium levels in BAL neutrophils were measured. RNA sequencing of BAL neutrophils was conducted to assess C6-induced transcriptional changes. Key findings were validated in vitro using human neutrophils. Results: C6 mitigates P. aeruginosa-induced ALI in mice by reducing neutrophil infiltration into the alveolar space by ~ 86%,improving lung injury scores,decreasing BAL fluid proinflammatory cytokine levels,and suppressing neutrophil ROS production and intracellular calcium levels. RNA sequencing of BAL neutrophils revealed 51 downregulated genes,including key regulators of neutrophil migration,cytokine release,and ROS production; only three genes were upregulated and they also have roles in neutrophil immune defense. In human neutrophils,C6 similarly inhibited chemotaxis and reduced ROS and cytokine release,and calcium influx. Conclusions: Targeting Hv1 with C6 effectively protects against P. aeruginosa-induced ALI by limiting neutrophil recruitment and activation. These findings establish C6 as a promising therapeutic candidate against infectious ALI and provide important mechanistic insights into its immunomodulatory effects on neutrophils. View Publication

How the neuroectoderm-derived eye field breaks symmetry to specify iris muscle is not well understood. Recent studies have begun to transcriptionally characterize mouse iris muscle; however,little is known about the transcriptional foundation of human iris development. Human pluripotent stem cells (hPSCs) enable the study of iris muscle specification. Here we compare iris smooth muscle from native adult iris tissues to evaluate successful specification of iris muscle from hPSC lines. We utilize a previously published eye-like organoid protocol that specified cells of the eye field to also generate iris muscle. We describe a population transcriptionally similar to native iris and describe an iris muscle gene signature. Human iris muscle not only contains pigment,but also expresses pigment synthesis genes and is responsive to acetylcholine. Integration of single-cell RNA-seq datasets confirm the similarity between the iris muscle to the adult iris,establishing the usefulness of the model in studying neuroectoderm-derived iris muscle specification,and related diseases. Single-cell RNA sequencing reveals that iris muscle,derived from neuroectoderm,can form in stem cell–derived eye organoids – enabling the modelling of iris muscle pathologies like aniridia and proliferative vitreoretinopathy. View Publication

USP30,a ubiquitin‐specific protease,primarily characterized as a mitochondrial deubiquitinase regulating mitophagy,has not been previously reported to have nuclear functions. In this study,we demonstrate that USP30 is present in both mitochondrial and nuclear compartments. Nutrient deprivation triggers USP30 nuclear translocation via an N‐terminal nuclear localization signal (NLS),mediated through suppression of mTORC1‐dependent phosphorylation at serine 104,a modification constraining nuclear entry. Nuclear USP30 acts as a tumor suppressor by inhibiting cancer stemness and chemoresistance in triple‐negative breast cancer (TNBC) cells. Mechanistically,USP30 directly interacts with and deubiquitinates the transcription factor TCF/LEF1 at K379 and K382 residues,disrupting recruitment of CBP/P300 co‐activators to the β‐catenin/LEF1 complex. This abolishes β‐catenin/LEF1 transactivation and suppresses WNT signaling. Clinically,USP30 is downregulated in TNBC and cancer stem cells (CSCs),with notably reduced nuclear levels in cancer tissues. Overexpression of nuclear USP30 markedly reduces lung metastatic burden in TNBC mouse models. These findings uncover a novel role for nuclear USP30 in regulating cancer stemness and suggest that targeting the dynamic relocalization of USP30 from mitochondria to the nucleus could offer new therapeutic strategies for breast cancer metastasis. View Publication

Eosinophils are major effector cells in type 2 immune responses,contributing to host defense and allergic diseases. They also contribute to maintaining tissue homeostasis by regulating various immune cell types,including neutrophils. Here we show that eosinophils directly associate with neutrophils in the lungs of asthma-induced mice. Eosinophil-specific deficiency of the short-chain fatty acid receptor,GPR43,results in hyperactivation of eosinophils and increases the expression of neutrophil chemoattractants and PECAM-1,thereby enhancing the interaction between eosinophils and neutrophils. This interaction exposes neutrophils to eosinophil-derived IL-4 and GM-CSF,which induce the conversion of conventional neutrophils into more pathogenic,Siglec-Fhi neutrophils capable of enhancing Th17 cell differentiation and aggravating asthma symptoms in mouse models. Our results thus implicate GPR43 as a critical regulator of eosinophils,and describe eosinophil-mediated modulation of neutrophil differentiation and function. Eosinophils contribute to type 2 immunity,but their interaction with neutrophils in this context is incompletely understood. Here the authors use mouse asthma models and in vitro culture to show that eosinophil-specific deficiency of GPR43 promotes Siglec-Fhi neutrophil differentiation and downstream induction of Th17 to aggravate lung inflammation and asthma. View Publication

Background: Biliary atresia (BA) is the most prevalent serious neonatal biliary obstructive disorder and is a complex multifactorial liver disorder. Genome-wide association studies have identified Adducin 3 (ADD3) as a BA susceptibility gene but the mechanisms involved in disease causation and progression remain unclear. Methods: ADD3 knockout human pluripotent stem cells were differentiated into cholangiocyte organoids to assess the effect of ADD3 deletion on biliary development in vitro. Add3 deletion in rhesus rotavirus (RRV)-induced experimental BA mice were employed as the in vivo model to address the impact of reduced Add3 expression on BA pathogenesis. Findings: ADD3 knockout organoids displayed defective cholangiocyte differentiation,failure in the recruitment of βII-spectrin to the cell membrane,abnormal primary cilia development,reduced expression of tight junction proteins,lower transepithelial electrical resistance (TEER) and increased paracellular permeability. Statistical significantly reduced tight junction (TJ) proteins expression and lower TEER in Add3+/− and Add3−/− liver tissue-derived cholangiocytes were observed. Reduced number of TJs and enlarged paracellular spaces without any detectable TJ were detected in the intra-hepatic bile ducts of Add3+/− and Add3−/− livers. A statistical significantly higher incidence and a more advanced form of BA with statistical significantly higher serum bilirubin,liver necrosis and fibrosis,and accumulation of macrophages and activated hepatic stellate cells were observed in Add3 knockout BA mice as compared to wild-type BA mice. Interpretation: Dysregulated ADD3 expression caused an abnormal development and impaired barrier function of cholangiocytes,and the resultant increase in bile duct permeability rendered the foetus/neonate susceptible to a more severe injury response to an external insult. The findings support the hypothetical pathogenic model of genetic susceptibility genes being involved in hepatobiliary development/structure,and the perturbed embryogenesis of the biliary tree and its disrupt integrity increase the host susceptibility to biliary injury and BA. View Publication

Gastrointestinal (GI) dysfunction,characterized by severe diarrhea and dehydration,is a central contributor to morbidity and mortality in filovirus disease in patients,yet the role of the epithelium in this clinical outcome remains poorly defined. Here,we employ induced pluripotent stem cell (iPSC)-derived human intestinal (HIOs) and colonic organoids (HCOs) to model Ebola virus (EBOV) and Marburg virus (MARV) infection. These organoids are permissive to filovirus infection and support viral replication. Bulk RNA sequencing revealed distinct intestinal and colonic epithelial responses,including apical and junctional disruption and a delayed virus-specific induction of interferon-stimulated genes. Moreover,infection impaired adenylate cyclase signaling and CFTR-mediated ion transport,providing mechanistic insight into virus-induced secretory diarrhea. This platform recapitulates key features of human GI pathology in filoviral disease and serves as a powerful system to dissect host-pathogen interactions and identify therapeutic targets. Author summaryEbola virus (EBOV) and Marburg virus (MARV) are among the most lethal viruses known. Infection with these viruses leads to severe disease and death. One of their most harmful effects is damage to the gastrointestinal tract,causing intense diarrhea and life-threatening dehydration. Yet,how these viruses affect the gut remains poorly understood. In this study,we used human mini-guts—small,three-dimensional tissues grown from stem cells that mimic the human intestinal and colonic epithelium—to investigate how these viruses interact with gut epithelial cells. We found that both EBOV and MARV infect and replicate in these tissues,disrupt key barrier structures,and interfere with the cells’ ability to regulate fluid secretion. These effects mirror the severe symptoms seen in patients. Our study provides new insight into how EBOV and MARV damage the gut and identifies specific cellular pathways that may be targeted for treatment. This research not only improves our understanding of EBOV and MARV infections but also offers new infection platforms for testing therapies aimed at protecting the gastrointestinal system during filovirus outbreaks. View Publication