技术资料

Biological mechanisms are inherently dynamic,requiring precise and rapid manipulations for effective characterization. Traditional genetic manipulations operate on long timescales,making them unsuitable for studying dynamic processes or characterizing essential genes,where chronic depletion can cause cell death. We compare five inducible protein degradation systems—dTAG,HaloPROTAC,IKZF3,and two auxin-inducible degrons (AID) using OsTIR1 and AtFB2—evaluating degradation efficiency,basal degradation,target recovery after ligand washout,and ligand impact. This analysis identifies OsTIR1-based AID 2.0 as the most robust system. However,AID 2.0’s higher degradation efficiency comes with target-specific basal degradation and slower recovery rates. To address these limitations,we employ base-editing-mediated mutagenesis followed by several rounds of functional selection and screening. This directed protein evolution generates several gain-of-function OsTIR1 variants,including S210A,that significantly enhance the overall degron efficiency. The resulting degron system,named AID 2.1,maintains effective target protein depletion with minimal basal degradation and faster recovery after ligand washout,enabling characterization and rescue experiments for essential genes. Our comparative assessment and directed evolution approach provide a reference dataset and improved degron technology for studying gene functions in dynamic biological contexts. Subject terms: Genetic engineering,CRISPR-Cas9 genome editing,Peptides View Publication

Age-related macular degeneration (AMD) is a leading cause of blindness worldwide,with a clinical presentation that varies between sexes. In late-stage AMD,choroidal neovascularization (CNV) triggers retinal inflammation and degeneration,processes that are exacerbated by an overactive response of retinal microglial cells. Short-chain fatty acids (SCFAs) have emerged as potential treatments for AMD due to their anti-inflammatory properties. In this study,we investigate the effects of SCFA treatment in a laser-induced CNV mouse model,focusing on sex-dependent differences in disease progression and microglial response. Our findings demonstrate distinct sex-specific patterns in the development of CNV and associated pathological hallmarks. SCFA treatment resulted in a slight increase in density of Iba1 + microglial cells in females at 3 days post-laser (3dpl),while it prevented an increase in males at 7 dpl,with both sexes showing enhanced microglial ramification. The dynamics of microglial density were likely linked to protective effects on CNV lesion,leakage size,and inflammation,which occurred earlier in females and later in males. At transcriptional level,SCFA showed mixed effects,mainly targeting inflammation resolution,mitochondrial support,and neuronal repair in a sex-dependent manner. In vitro,SCFAs reduced microglial phagocytosis of retinal debris,suggesting a potential anti-inflammatory action. This study underscores the importance of considering sex-specific responses in the development of AMD treatments,such as SCFAs,and highlights the need for personalized therapeutic strategies. The online version contains supplementary material available at 10.1186/s12974-025-03508-1. View Publication

Respiratory syncytial virus (RSV) infection in the upper respiratory tract promotes disease progression and transmission,with excessive inflammation contributing to severe lower respiratory tract involvement. This study investigates the immunomodulatory effects of Lactobacillus rhamnosus D3189 on viral kinetics and innate immune responses in well-differentiated nasal epithelial cells (WD-NECs). WD-NECs from healthy adult donors (N = 8) were cultured in vitro,treated with L. rhamnosus D3189,and then infected with RSV (strain RS4) 24 hours later. Viral replication and shedding were assessed via RT-qPCR and plaque assays. Cytotoxicity and epithelial integrity were evaluated using LDH release and transepithelial electrical resistance (TEER). Inflammatory and antiviral responses were investigated using multiplex immunoassays,AlphaLISA,and ELISA. RSV infection induced robust viral replication and shedding,disrupted epithelial barrier integrity,and triggered the release of pro-inflammatory cytokines and type I/III interferons. L. rhamnosus D3189 alone did not induce cytotoxicity or inflammation. While it had no effect on viral replication,TEER,LDH release,or IFN-λ1/3 levels,D3189 significantly enhanced IFN-β production,reduced viral shedding,and attenuated RSV-induced cytokine and chemokine responses. L. rhamnosus D3189 modulates the epithelial immune response to RSV,reducing inflammation and viral shedding without compromising epithelial integrity. These findings support its potential as a novel strategy to limit RSV-associated infection and transmission. View Publication

Peroxisome proliferator-activated receptor gamma (PPARG) is a nuclear receptor family transcription factor (TF) critical for adipogenesis,lipid metabolism,insulin sensitivity,and inflammation. It has also been known to play essential roles in trophoblast development and placentation. Dysregulation of PPARG in trophoblast differentiation has been implicated in pregnancy complications,such as pre-eclampsia and gestational diabetes. However,the molecular mechanisms of PPARG-dependent target gene regulation and its interactions with other regulatory factors during human trophoblast differentiation remain unclear. Using human trophoblast stem cells (TSCs),mimicking placental cytotrophoblasts (CTs),and their differentiation into extravillous trophoblasts (EVTs) as our models,we reveal that PPARG has cell-type-specific targets in TSCs and EVTs. We also find that while PPARG is essential for both TSC self-renewal and EVT differentiation,only its role in EVT differentiation is ligand sensitive and requires ligand-binding domain (LBD)-mediated transcriptional activity,whereas its function in TSC self-renewal appears to be ligand insensitive. Combined analysis with chromosomal targets of previously defined key TFs in TSCs and EVTs shows that PPARG forms trophoblast cell-type-specific regulatory circuitries,leading to differential target gene regulation via transcriptional re-wiring during EVT differentiation. Additionally,the enhanced invasiveness of EVTs treated with a PPARG agonist suggests a potential connection between PPARG pathways and human placenta accreta. View Publication

Type 1 diabetes (T1D) results from the autoimmune-mediated loss of pancreatic β-cells. Current insulin therapies offer symptomatic relief but fall short of providing a definitive cure. Islet cell transplantation,while promising,faces limitations related to donor scarcity,procedural complexities,and the necessity for long-term immunosuppression. Consequently,there is an urgent need for innovative strategies aimed at β-cell regeneration. Patient-derived induced pluripotent stem cells (iPSCs),obtained from peripheral blood mononuclear cells (PBMCs) of T1D patients,hold great potential as a source of cells for therapeutic purposes. Therefore,the differentiation of T1D-iPSCs into functional pancreatic β-cells is a critical step toward effective β-cell replacement therapy. To assess the potential of patient-derived T1D-β-like cells (differentiated from T1D-iPSCs reprogrammed from T1D-PBMCs) for restoring β-cell function in T1D. T1D-iPSCs were reprogrammed from T1D-PBMCs using an episomal vector-based approach. Pluripotency was confirmed by flow cytometry (FCM),quantitative real-time polymerase chain reaction,genomic stability analysis,and teratoma formation assays. Differentiation into pancreatic β-cells was optimized using triiodothyronine (T3),vitamin C (Vc),and an adenovirus (M3C) encoding pancreatic duodenal homeobox-1,neurogenin 3 ( Ngn3 ),and MAF bZIP transcription factor A ( MafA ). Following characterization of β-cell features by immunofluorescence,quantitative real-time polymerase chain reaction,and flow cytometry,therapeutic efficacy was assessed through blood glucose monitoring after transplantation under the renal capsule of streptozotocin-induced diabetic mice. T1D-iPSCs were successfully generated from T1D-PBMCs. These cells exhibited the hallmark characteristics of pluripotent stem cells,including appropriate morphology,differentiation potential,genomic integrity,and expression of pluripotency-associated genes. Differentiation yielded insulin-positive (insulin + ) pancreatic β-like cells that,at the mRNA level,expressed key β-cell markers such as pancreatic duodenal homeobox-1,Ngn3,MafA,NeuroD,glucagon-like peptide-1 receptor,Nkx6.1,glucose transporter 2,and Kir6.2 . Notably,the T3 + Vc group displayed the lowest Ngn3 expression (1.31 ± 0.38 vs 1.96 ± 0.25 vs 2.51 ± 0.24,P < 0.01),while the M3C + T3 + Vc group exhibited the highest MafA expression (0.49 ± 0.11 vs 0.32 ± 0.06 vs 0.29 ± 0.08,P < 0.05). Both in vitro and in vivo assessments confirmed the insulin secretion ability of the generated β-like cells; however,they did not demonstrate appropriate modulation of insulin release in response to variations in extracellular glucose concentrations. T1D-iPSCs derived from T1D-PBMCs can be differentiated into insulin + β-like cells,albeit with functional immaturity. These cells represent a potential source of seed cells for β-cell replacement therapy in T1D. View Publication

Transplantation of engineered B cells has demonstrated efficacy in HIV disease models. B cell engineering may also be utilized for the treatment of cancer. Recent studies have highlighted that B cell activity is associated with favorable clinical outcomes in oncology. In mice,polyclonal B cells have been shown to elicit anti-cancer responses. As a potential novel cell therapy,we demonstrate that engineering B cells to target a tumor-associated antigen enhances polyclonal anti-tumor responses. We observe that engineered B cells expressing an anti-HPV B cell receptor internalize the antigen,enabling subsequent activation of oncoantigen-specific T cells. Secreted antibodies from engineered B cells form immune complexes,which are taken up by antigen-presenting cells to further promote T cell activation. Engineered B cells hold promise as novel,multi-modal cell therapies and open new avenues in solid tumor targeting. View Publication

Anti-obesity medications (AOMs) have become one of the most prescribed drugs in human medicine. While AOMs are known to impact adult neurogenesis in the hypothalamus,their effects on the functional maturation of hypothalamic neurons remain unexplored. Given that AOMs target neurons in the Medial Basal Hypothalamus (MBH),which play a crucial role in regulating energy homeostasis,we hypothesized that AOMs might influence the functional maturation of these neurons,potentially rewiring the MBH. To investigate this,we exposed hypothalamic neurons derived from human induced pluripotent stem cells (hiPSCs) to Semaglutide and lipidized prolactin-releasing peptide (LiPR),two anti-obesity compounds. Contrary to our expectations,treatment with Semaglutide or LiPR during neuronal maturation did not affect the proportion of anorexigenic,Pro-opiomelanocortin-expressing (POMC+) neurons. Additionally,LiPR did not alter the morphology of POMC+ neurons or the expression of selected genes critical for the metabolism or development of anorexigenic neurons. Furthermore,LiPR did not impact the proportion of adult-generated POMC+ neurons in the mouse MBH. Taken together,these results suggest that AOMs do not influence the functional maturation of anorexigenic hypothalamic neurons. View Publication

The limited proliferative capacity of erythroid precursors is a major obstacle to generate sufficient in vitro-derived red blood cells for clinical purposes. While BMI1,a Polycomb Repressive Complex 1 member,is both necessary and sufficient to drive extensive proliferation of self-renewing erythroblasts,its mechanism of action remains poorly understood. Here we report that BMI1 overexpression leads to 10 billion-fold increase in self-renewal of human erythroblasts,which can terminally mature and agglutinate with typing reagent monoclonal antibodies. BMI1 and RING1B occupancy,along with repressive histone marks,are present at known BMI1 target genes,including the INK-ARF locus,consistent with altered cell cycle kinetics following BMI1 inhibition. Upregulation of BMI1 target genes with low repressive histone modifications,including key regulators of cholesterol homeostasis,along with functional studies,suggest that both cholesterol import and synthesis are essential for BMI1-associated self-renewal. We conclude that BMI1 regulates erythroid self-renewal not only through gene repression but also through gene activation and offer a strategy to expand immature erythroid precursors for eventual clinical uses. Subject terms: Self-renewal,Cell growth,Stem-cell research View Publication

Strategies targeting leukemic stem and progenitor cells (LSPCs) are needed for durable remissions in acute myeloid leukemia (AML) and high-risk myelodysplastic neoplasms (MDS). While CD123 constitutes a promising target on LSPCs and leukemic blasts,previous CD123-targeting approaches showed limited efficacy and challenging safety profiles. Here,we describe the preclinical efficacy and safety of the bispecific CD123/CD16A innate cell engager “AFM28”,demonstrating superior activity against AML and MDS patient-derived LSPCs and blasts in vitro compared to an Fc-enhanced CD123-targeting antibody,especially towards CD123 low and/or CD64 + leukemic cells. AFM28 induces autologous anti-leukemic activity in fresh AML whole blood cultures,demonstrating its potential to enhance NK cell function from AML patients. Responsiveness can be further enhanced by allogeneic NK cell addition. Anti-leukemic activity of AFM28 is confirmed in xenograft mouse models. In addition,AFM28 is well tolerated and demonstrates pharmacodynamic activity in cynomolgus monkeys. Altogether,our results indicate that AFM28 has the potential to reduce relapse-inducing residual disease and promote long-term remissions for patients with AML and MDS with a favorable safety profile. Subject terms: Cancer immunotherapy,Preclinical research,Acute myeloid leukaemia,Myelodysplastic syndrome View Publication

Spinal cord injury (SCI) remains a significant clinical challenge and poses a dramatic threat to the life quality of patients due to limited neural regeneration and detrimental post-injury alternations in tissue microenvironment. We developed a therapeutic approach by transplanting spinal neural progenitor cells (spNPGs),derived from human induced pluripotent stem cell (iPSC)-generated neuromesodermal progenitors,into a contusive SCI model in NOD-SCID mice. Single-cell RNA sequencing mapped the in vitro differentiation of iPSC-spNPGs,confirming their specification into spinal neuronal lineages. Single-nucleus transcriptomics at 1 week post-transplantation showed that the grafted cells differentiated in vivo into motor neurons and two interneuron subtypes (V2 and dI4). Additionally,spNPGs integrated into host neural circuits,enhancing synaptic connectivity,while simultaneously modulating the injury microenvironment by shifting microglia and astrocyte polarization toward anti-inflammatory and neuroprotective phenotypes. This dual mechanism promoted axonal regrowth,remyelination,and significant sensorimotor recovery,as evidenced by improved locomotor scores. Our findings highlight the therapeutic potential of human iPSC-spNPGs in reconstructing neural networks and mitigating secondary damage,providing compelling preclinical evidence for advancing stem cell-based SCI therapies. Subject terms: Stem-cell differentiation,Spinal cord injury View Publication

Renal failure due to drug nephrotoxicity or disease is frequently observed in patients. The development of in vitro models able to recapitulate kidney biology offers new possibilities to study drug toxicity or model diseases. Induced pluripotent stem cell–derived kidney organoids already show promise,but several drawbacks must be overcome to maintain them in culture,among which is the presence of non-renal cell populations such as cartilage. We modified the culture protocol and maintained kidney organoids in medium containing FGF9 for 1 additional week compared to the control protocol (Takasato). In comparison to the control,the FGF9-treated kidney organoids had reduced cartilage at day 7 + 25 and diminished chondrocyte marker expression. Importantly,the renal structures assessed by immunofluorescence were unaffected by the FGF9 treatment. This reduction of cartilage produces a higher quality kidney organoid that can be maintained longer in culture to improve their maturation for further in vivo work. Subject terms: Pluripotent stem cells,Stem-cell differentiation,Kidney View Publication

Cholesterol is an essential plasma membrane component,and altered cholesterol metabolism has been linked to cholesterol accumulation in the airways of COPD and cystic fibrosis patients. However,its role in airway epithelial differentiation is not well understood. Tandem mass spectrometry-based proteomic analysis of differentiating primary human bronchial epithelial cells (phBECs) revealed an overall inhibition of the cholesterol biosynthesis pathway. We hypothesized that excess cholesterol impairs the differentiation of phBECs into a fully functional bronchial epithelium. PhBECs were differentiated in the presence of 80 µM cholesterol for 21 days,the main airway cell type populations monitored using qRT-PCR and immunofluorescent stainings,and epithelial barrier integrity was analyzed via transepithelial electrical resistance measurements. Chronic cholesterol exposure led to a significant increase in CC10 + secretory cells at the expense of ciliated cells. Pathway enrichment analysis suggested the tumor protein p53 as a master regulator of genes during normal differentiation of phBECs. Chronic cholesterol exposure drastically impaired the nuclear translocation of p53. Our findings suggest that this inhibition underlies the cholesterol-induced expansion of CC10 + secretory cell populations at the expense of ciliated cells. In conclusion,we identify cholesterol as an important regulator of normal bronchial epithelial cell differentiation through inhibition of p53 nuclear translocation. View Publication