Watson CL et al. (NOV 2014)
Nature Medicine 20 11 1310--4
An in vivo model of human small intestine using pluripotent stem cells.
Differentiation of human pluripotent stem cells (hPSCs) into organ-specific subtypes offers an exciting avenue for the study of embryonic development and disease processes,for pharmacologic studies and as a potential resource for therapeutic transplant. To date,limited in vivo models exist for human intestine,all of which are dependent upon primary epithelial cultures or digested tissue from surgical biopsies that include mesenchymal cells transplanted on biodegradable scaffolds. Here,we generated human intestinal organoids (HIOs) produced in vitro from human embryonic stem cells (ESCs) or induced pluripotent stem cells (iPSCs) that can engraft in vivo. These HIOs form mature human intestinal epithelium with intestinal stem cells contributing to the crypt-villus architecture and a laminated human mesenchyme,both supported by mouse vasculature ingrowth. In vivo transplantation resulted in marked expansion and maturation of the epithelium and mesenchyme,as demonstrated by differentiated intestinal cell lineages (enterocytes,goblet cells,Paneth cells,tuft cells and enteroendocrine cells),presence of functional brush-border enzymes (lactase,sucrase-isomaltase and dipeptidyl peptidase 4) and visible subepithelial and smooth muscle layers when compared with HIOs in vitro. Transplanted intestinal tissues demonstrated digestive functions as shown by permeability and peptide uptake studies. Furthermore,transplanted HIO-derived tissue was responsive to systemic signals from the host mouse following ileocecal resection,suggesting a role for circulating factors in the intestinal adaptive response. This model of the human small intestine may pave the way for studies of intestinal physiology,disease and translational studies.
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Cesaro A et al. (SEP 2012)
PLoS ONE 7 9 e45478
An inflammation loop orchestrated by S100A9 and Calprotectin is critical for development of arthritis
OBJECTIVE: The S100A9 and S100A8 proteins are highly expressed by neutrophils and monocytes and are part of a group of damage-associated molecular pattern molecules that trigger inflammatory responses. Sera and synovial fluids of patients with rheumatoid arthritis (RA) contain high concentrations of S100A8/A9 that correlate with disease activity.backslashnbackslashnMETHODS: In this study,we investigated the importance of S100A9 in RA by using neutralizing antibodies in a murine lipopolysaccharide-synchronized collagen-induced arthritis model. We also used an in vitro model of stimulation of human immune cells to decipher the role played by S100A9 in leukocyte migration and pro-inflammatory cytokine secretion.backslashnbackslashnRESULTS: Treatment with anti-S100A9 antibodies improved the clinical score by 50%,diminished immune cell infiltration,reduced inflammatory cytokines,both in serum and in the joints,and preserved bone/collagen integrity. Stimulation of neutrophils with S100A9 protein led to the enhancement of neutrophil transendothelial migration. S100A9 protein also induced the secretion by monocytes of proinflammatory cytokines like TNFα,IL-1β and IL-6,and of chemokines like MIP-1α and MCP-1.backslashnbackslashnCONCLUSION: The effects of anti-S100A9 treatment are likely direct consequences of inhibiting the S100A9-mediated promotion of neutrophil transmigration and secretion of pro-inflammatory cytokines from monocytes. Collectively,our results show that treatment with anti-S100A9 may inhibit amplification of the immune response and help preserve tissue integrity. Therefore,S100A9 is a promising potential therapeutic target for inflammatory diseases like rheumatoid arthritis for which alternative therapeutic strategies are needed.
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Wilson JR et al. (NOV 2016)
Antiviral Research 135 48--55
An influenza A virus (H7N9) anti-neuraminidase monoclonal antibody with prophylactic and therapeutic activity in vivo
Zoonotic A(H7N9) avian influenza viruses emerged in China in 2013 and continue to be a threat to human public health,having infected over 800 individuals with a mortality rate approaching 40%. Treatment options for people infected with A(H7N9) include the use of neuraminidase (NA) inhibitors. However,like other influenza viruses,A(H7N9) can become resistant to these drugs. The use of monoclonal antibodies is a rapidly developing strategy for controlling influenza virus infection. Here we generated a murine monoclonal antibody (3c10-3) directed against the NA of A(H7N9) and show that prophylactic systemic administration of 3c10-3 fully protected mice from lethal challenge with wild-type A/Anhui/1/2013 (H7N9). Further,post-infection treatment with a single systemic dose of 3c10-3 at either 24,48 or 72 h post A(H7N9) challenge resulted in both dose- and time-dependent protection of up to 100% of mice,demonstrating therapeutic potential for 3c10-3. Epitope mapping revealed that 3c10-3 binds near the enzyme active site of NA,and functional characterization showed that 3c10-3 inhibits the enzyme activity of NA and restricts the cell-to-cell spread of the virus in cultured cells. Affinity analysis also revealed that 3c10-3 binds equally well to recombinant NA of wild-type A/Anhui/1/2013 and to a variant NA carrying a R289K mutation known to infer NAI resistance. These results suggest that 3c10-3 has the potential to be used as a therapeutic to treat A(H7N9) infections either as an alternative to,or in combination with,current NA antiviral inhibitors.
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S. Downey-Kopyscinski et al. (OCT 2018)
Blood advances 2 19 2443--2451
An inhibitor of proteasome $\beta$2 sites sensitizes myeloma cells to immunoproteasome inhibitors.
Proteasome inhibitors bortezomib,carfilzomib and ixazomib (approved by the US Food and Drug Administration [FDA]) induce remissions in patients with multiple myeloma (MM),but most patients eventually become resistant. MM and other hematologic malignancies express ubiquitous constitutive proteasomes and lymphoid tissue-specific immunoproteasomes; immunoproteasome expression is increased in resistant patients. Immunoproteasomes contain 3 distinct pairs of active sites,$\beta$5i,$\beta$1i,and $\beta$2i,which are different from their constitutive $\beta$5c,$\beta$1c,and $\beta$2c counterparts. Bortezomib and carfilzomib block $\beta$5c and $\beta$5i sites. We report here that pharmacologically relevant concentrations of $\beta$5i-specific inhibitor ONX-0914 show cytotoxicity in MM cell lines similar to that of carfilzomib and bortezomib. In addition,increasing immunoproteasome expression by interferon-$\gamma$ increases sensitivity to ONX-0914 but not to carfilzomib. LU-102,an inhibitor of $\beta$2 sites,dramatically sensitizes MM cell lines and primary cells to ONX-0914. ONX-0914 synergizes with all FDA-approved proteasome inhibitors in MM in vitro and in vivo. Thus,immunoproteasome inhibitors,currently in clinical trials for the treatment of autoimmune diseases,should also be considered for the treatment of MM.
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Mahtouk K et al. (MAR 2004)
Blood 103 5 1829--37
An inhibitor of the EGF receptor family blocks myeloma cell growth factor activity of HB-EGF and potentiates dexamethasone or anti-IL-6 antibody-induced apoptosis.
We previously found that some myeloma cell lines express the heparin-binding epidermal growth factor-like growth factor (HB-EGF) gene. As the proteoglycan syndecan-1 is an HB-EGF coreceptor as well as a hallmark of plasma cell differentiation and a marker of myeloma cells,we studied the role of HB-EGF on myeloma cell growth. The HB-EGF gene was expressed by bone marrow mononuclear cells in 8 of 8 patients with myeloma,particularly by monocytes and stromal cells,but not by purified primary myeloma cells. Six of 9 myeloma cell lines and 9 of 9 purified primary myeloma cells expressed ErbB1 or ErbB4 genes coding for HB-EGF receptor. In the presence of a low interleukin-6 (IL-6) concentration,HB-EGF stimulated the proliferation of the 6 ErbB1+ or ErbB4+ cell lines,through the phosphatidylinositol 3-kinase/AKT (PI-3K/AKT) pathway. A pan-ErbB inhibitor blocked the myeloma cell growth factor activity and the signaling induced by HB-EGF. This inhibitor induced apoptosis of patients'myeloma cells cultured with their tumor environment. It also increased patients' myeloma cell apoptosis induced by an anti-IL-6 antibody or dexamethasone. The ErbB inhibitor had no effect on the interaction between multiple myeloma cells and stromal cells. It was not toxic for nonmyeloma cells present in patients' bone marrow cultures or for the growth of hematopoietic progenitors. Altogether,these data identify ErbB receptors as putative therapeutic targets in multiple myeloma.
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E. Yi et al. (Apr 2025)
Respiratory Research 26 10131
An integrated machine learning model of transcriptomic genes in multi-center chronic obstructive pulmonary disease reveals the causal role of TIMP4 in airway epithelial cell
Chronic obstructive pulmonary disease (COPD) is a heterogeneous syndrome,resulting in inconsistent findings across studies. Identifying a core set of genes consistently involved in COPD pathogenesis,independent of patient variability,is essential. We integrated lung tissue sequencing data from patients with COPD across two centers. We used weighted gene co-expression network analysis and machine learning to identify 13 potential pathogenic genes common to both centers. Additionally,a gene-based model was constructed to distinguish COPD at the molecular level and validated in independent cohorts. Gene expression in specific cell types was analyzed,and Mendelian randomization was used to confirm associations between candidate genes and lung function/COPD. Preliminary in vitro functional validation was performed on prioritized core candidate genes. Tissue inhibitor of metalloproteinase 4 (TIMP4) was identified as a key pathogenic gene and validated in COPD cohorts. Further analysis using single-cell sequencing from mice and patients with COPD revealed that TIMP4 is involved in ciliated cells. In primary human airway epithelial cells cultured at the air-liquid interface,TIMP4 overexpression reduced ciliated cell numbers. We developed a 13-gene model for distinguishing COPD at the molecular level and identified TIMP4 as a potential hub pathogenic gene. This finding provides insights into shared disease mechanisms and positions TIMP4 as a promising therapeutic target for further investigation. The online version contains supplementary material available at 10.1186/s12931-025-03238-1.
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I. Haq et al. (Apr 2024)
Stem Cell Research & Therapy 15 6005
An integrated toolkit for human microglia functional genomics
Microglia,the brain’s resident immune cells,play vital roles in brain development,and disorders like Alzheimer’s disease (AD). Human iPSC-derived microglia (iMG) provide a promising model to study these processes. However,existing iMG generation protocols face challenges,such as prolonged differentiation time,lack of detailed characterization,and limited gene function investigation via CRISPR-Cas9. Our integrated toolkit for in-vitro microglia functional genomics optimizes iPSC differentiation into iMG through a streamlined two-step,20-day process,producing iMG with a normal karyotype. We confirmed the iMG’s authenticity and quality through single-cell RNA sequencing,chromatin accessibility profiles (ATAC-Seq),proteomics and functional tests. The toolkit also incorporates a drug-dependent CRISPR-ON/OFF system for temporally controlled gene expression. Further,we facilitate the use of multi-omic data by providing online searchable platform that compares new iMG profiles to human primary microglia: https://sherlab.shinyapps.io/IPSC-derived-Microglia/ . Our method generates iMG that closely align with human primary microglia in terms of transcriptomic,proteomic,and chromatin accessibility profiles. Functionally,these iMG exhibit Ca2 + transients,cytokine driven migration,immune responses to inflammatory signals,and active phagocytosis of CNS related substrates including synaptosomes,amyloid beta and myelin. Significantly,the toolkit facilitates repeated iMG harvesting,essential for large-scale experiments like CRISPR-Cas9 screens. The standalone ATAC-Seq profiles of our iMG closely resemble primary microglia,positioning them as ideal tools to study AD-associated single nucleotide variants (SNV) especially in the genome regulatory regions. Our advanced two-step protocol rapidly and efficiently produces authentic iMG. With features like the CRISPR-ON/OFF system and a comprehensive multi-omic data platform,our toolkit equips researchers for robust microglial functional genomic studies. By facilitating detailed SNV investigation and offering a sustainable cell harvest mechanism,the toolkit heralds significant progress in neurodegenerative disease drug research and therapeutic advancement. The online version contains supplementary material available at 10.1186/s13287-024-03700-9.
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Ting S et al. (SEP 2014)
Stem Cell Research 13 2 202--213
An intermittent rocking platform for integrated expansion and differentiation of human pluripotent stem cells to cardiomyocytes in suspended microcarrier cultures
The development of novel platforms for large scale production of human embryonic stem cells (hESC) derived cardiomyocytes (CM) becomes more crucial as the demand for CMs in preclinical trials,high throughput cardio toxicity assays and future regenerative therapeutics rises. To this end,we have designed a microcarrier (MC) suspension agitated platform that integrates pluripotent hESC expansion followed by CM differentiation in a continuous,homogenous process.Hydrodynamic shear stresses applied during the hESC expansion and CM differentiation steps drastically reduced the capability of the cells to differentiate into CMs. Applying vigorous stirring during pluripotent hESC expansion on Cytodex 1 MC in spinner cultures resulted in low CM yields in the following differentiation step (cardiac troponin-T (cTnT): 22.83. ??. 2.56%; myosin heavy chain (MHC): 19.30. ??. 5.31%). Whereas the lower shear experienced in side to side rocker (wave type) platform resulted in higher CM yields (cTNT: 47.50. ??. 7.35%; MHC: 42.85. ??. 2.64%). The efficiency of CM differentiation is also affected by the hydrodynamic shear stress applied during the first 3. days of the differentiation stage. Even low shear applied continuously by side to side rocker agitation resulted in very low CM differentiation efficiency (cTnT. textless. 5%; MHC. textless. 2%). Simply by applying intermittent agitation during these 3. days followed by continuous agitation for the subsequent 9. days,CM differentiation efficiency can be substantially increased (cTNT: 65.73. ??. 10.73%; MHC: 59.73. ??. 9.17%). These yields are 38.3% and 39.3% higher (for cTnT and MHC respectively) than static culture control.During the hESC expansion phase,cells grew on continuously agitated rocker platform as pluripotent cell/MC aggregates (166??88??105??m2) achieving a cell concentration of 3.74??0.55??106cells/mL (18.89??2.82 fold expansion) in 7days. These aggregates were further differentiated into CMs using a WNT modulation differentiation protocol for the subsequent 12days on a rocking platform with an intermittent agitation regime during the first 3days. Collectively,the integrated MC rocker platform produced 190.5??58.8??106 CMs per run (31.75??9.74 CM/hESC seeded). The robustness of the system was demonstrated by using 2 cells lines,hESC (HES-3) and human induced pluripotent stem cell (hiPSC) IMR-90. The CM/MC aggregates formed extensive sarcomeres that exhibited cross-striations confirming cardiac ontogeny. Functionality of the CMs was demonstrated by monitoring the effect of inotropic drug,Isoproterenol on beating frequency.In conclusion,we have developed a simple robust and scalable platform that integrates both hESC expansion and CM differentiation in one unit process which is capable of meeting the need for large amounts of CMs. ?? 2014.
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Wang Y et al. ( 2014)
Nature Communications 5 4432
An intestinal commensal symbiosis factor controls neuroinflammation via TLR2-mediated CD39 signalling
The mammalian immune system constitutively senses vast quantities of commensal bacteria and their products through pattern recognition receptors,yet excessive immune reactivity is prevented under homeostasis. The intestinal microbiome can influence host susceptibility to extra-intestinal autoimmune disorders. Here we report that polysaccharide A (PSA),a symbiosis factor for the human intestinal commensal Bacteroides fragilis,protects against central nervous system demyelination and inflammation during experimental autoimmune encephalomyelitis (EAE),an animal model for multiple sclerosis,through Toll-like receptor 2 (TLR2). TLR2 mediates tissue-specific expansion of a critical regulatory CD39(+) CD4 T-cell subset by PSA. Ablation of CD39 signalling abrogates PSA control of EAE manifestations and inflammatory cytokine responses. Further,CD39 confers immune-regulatory phenotypes to total CD4 T cells and Foxp3(+) CD4 Tregs. Importantly,CD39-deficient CD4 T cells show an enhanced capability to drive EAE progression. Our results demonstrate the therapeutic potential and underlying mechanism by which an intestinal symbiont product modulates CNS-targeted demyelination.
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Zeng H et al. (SEP 2016)
Cell stem cell 19 3 326--340
An Isogenic Human ESC Platform for Functional Evaluation of Genome-wide-Association-Study-Identified Diabetes Genes and Drug Discovery.
Genome-wide association studies (GWASs) have increased our knowledge of loci associated with a range of human diseases. However,applying such findings to elucidate pathophysiology and promote drug discovery remains challenging. Here,we created isogenic human ESCs (hESCs) with mutations in GWAS-identified susceptibility genes for type 2 diabetes. In pancreatic beta-like cells differentiated from these lines,we found that mutations in CDKAL1,KCNQ1,and KCNJ11 led to impaired glucose secretion in vitro and in vivo,coinciding with defective glucose homeostasis. CDKAL1 mutant insulin+ cells were also hypersensitive to glucolipotoxicity. A high-content chemical screen identified a candidate drug that rescued CDKAL1-specific defects in vitro and in vivo by inhibiting the FOS/JUN pathway. Our approach of a proof-of-principle platform,which uses isogenic hESCs for functional evaluation of GWAS-identified loci and identification of a drug candidate that rescues gene-specific defects,paves the way for precision therapy of metabolic diseases.
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Wang Y et al. (MAR 2017)
Mucosal immunology 10 2 373--384
An LGG-derived protein promotes IgA production through upregulation of APRIL expression in intestinal epithelial cells.
p40,a Lactobacillus rhamnosus GG (LGG)-derived protein,transactivates epidermal growth factor receptor (EGFR) in intestinal epithelial cells,leading to amelioration of intestinal injury and inflammation. To elucidate mechanisms by which p40 regulates mucosal immunity to prevent inflammation,this study aimed to determine the effects and mechanisms of p40 on regulation of a proliferation-inducing ligand (APRIL) expression in intestinal epithelial cells for promoting immunoglobulin A (IgA) production. p40 upregulated April gene expression and protein production in mouse small intestine epithelial (MSIE) cells,which were inhibited by blocking EGFR expression and kinase activity. Enteroids from Egfr(fl/fl),but not Egfr(fl/fl)-Vil-Cre mice with EGFR specifically deleted in intestinal epithelial cells,exhibited increased April gene expression by p40 treatment. p40-conditioned media from MSIE cells increased B-cell class switching to IgA(+) cells and IgA production,which was suppressed by APRIL receptor-neutralizing antibodies. Treatment of B cells with p40 did not show any effects on IgA production. p40 treatment increased April gene expression and protein production in small intestinal epithelial cells,fecal IgA levels,IgA(+)B220(+),IgA(+)CD19(+),and IgA(+) plasma cells in lamina propria of Egfr(fl/fl),but not of Egfr(fl/fl)-Vil-Cre,mice. Thus p40 upregulates EGFR-dependent APRIL production in intestinal epithelial cells,which may contribute to promoting IgA production.
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Villa GR et al. (NOV 2016)
Cancer cell 30 5 683--693
An LXR-Cholesterol Axis Creates a Metabolic Co-Dependency for Brain Cancers.
Small-molecule inhibitors targeting growth factor receptors have failed to show efficacy for brain cancers,potentially due to their inability to achieve sufficient drug levels in the CNS. Targeting non-oncogene tumor co-dependencies provides an alternative approach,particularly if drugs with high brain penetration can be identified. Here we demonstrate that the highly lethal brain cancer glioblastoma (GBM) is remarkably dependent on cholesterol for survival,rendering these tumors sensitive to Liver X receptor (LXR) agonist-dependent cell death. We show that LXR-623,a clinically viable,highly brain-penetrant LXRα-partial/LXRβ-full agonist selectively kills GBM cells in an LXRβ- and cholesterol-dependent fashion,causing tumor regression and prolonged survival in mouse models. Thus,a metabolic co-dependency provides a pharmacological means to kill growth factor-activated cancers in the CNS.
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