Biology subjects

Lee, S.-H.

Publications and source records attributed to Lee, S.-H..

At least 37 records · Page 2Linked to original sources

bioRxiv2025

Engineering a Biomimetic Multiphasic Suture Anchor System for Enhanced Rotator Cuff Enthesis Regeneration

Conventional suture anchor methods in rotator cuff repair often fail to replicate the native tendon-to-bone interface, leading to re-tears due to stress concentrations and poor biological integration at anchor sites. To address these challenges, we engineered a biomimetic multiphasic scaffold system (BMS) that integrates with standard suture anchors and deliver spatially organized structural and biological cues to enhance enthesis regeneration. The BMS comprises three distinct phases: aligned nanofibrous decellularized bovine Achilles tendon extracellular matrix (dECM) with stiff methacrylated hyaluronic acid (MeHA) for tendon regeneration; nonaligned nanofibrous dECM with soft MeHA for fibrocartilage formation; and a porous, citrate-based composite scaffold with bioactive glass for bone integration. In vitro, the BMS facilitated zone-specific tenogenic, fibrochondrogenic, and chondrogenic differentiation. Further, in vivo, it promoted successful integrative healing, forming distinct tendon, fibrocartilage, and bone regions at the repair site. This advanced multiphasic scaffold replicates native tissue properties, offering a promising strategy to improve rotator cuff repair. Its integration with conventional suture anchors provides an innovative design that enhances mechanical fixation and guides enthesis healing to reduce re-tear rates. Broadly, this platform offers a versatile solution for biointegrative repair strategies across complex soft-to-hard tissue interfaces.

bioengineering↗

bioRxiv2025

AGO1 in neural progenitor cells orchestrates brain development and sociability via LIN28A-REELIN axis

AGO1, an essential RNA binding protein (RBP) in RNA interference, is associated with autism spectrum disorder (ASD). However, the precise functions of AGO1 in brain development and related disorders remain largely unexplored. Here, we report the critical roles of AGO1 in neural progenitor cells (NPCs) in promoting sociability and shaping the structure of the developing brain. Ago1 knockout (KO) in the mouse brain leads to hyposociability, a characteristic symptom of ASD. In human forebrain organoids, AGO1 KO disrupts the formation of ventricle-like structures and delays cortical layer development. We discovered that AGO1 KO results in a loss of polarity in NPCs, which subsequently reduces neuronal development. These AGO1 KO phenotypes originate from the failure to suppress LIN28A in NPCs. AGO1 is primarily localized in the nucleus within NPCs and binds to the LIN28A promoter region, thereby inhibiting LIN28A transcription. We found that increased LIN28A in AGO1 KO NPCs reduces REELIN expression, a key regulator of brain development, by binding directly to the REELIN mRNA. The aberrant polarity phenotype in AGO1 KO NPCs was successfully ameliorated by either LIN28A knockdown or recombinant REELIN treatment. Collectively, our findings elucidate the intricate molecular mechanisms orchestrated by nuclear AGO1 in NPCs and underscores its pivotal roles in brain development, providing significant insights into ASD.

neuroscience↗

bioRxiv2025

Biomarker Discovery via Integrative Multi-omics for Children exposed to Humidifier Disinfectant

RationaleExposure to humidifier disinfectants has been linked to an array of pulmonary disorders and diminished lung functionality particularly reduced Forced Vital Capacity (FVC). ObjectivesThis investigation sought to identify diagnostic biomarkers for early detection of children at elevated risk of developing chronic respiratory conditions following such exposure. MethodsOur research employed a comprehensive multi-omics strategy analyzing 70 pediatric patients alongside 10 controls, seamlessly integrating clinical assessments with transcriptomics, methylomics, proteomics, and metabolomics data. The analytical framework utilized a sophisticated combination of Non-negative Matrix Factorization (NMF), Multi-Omics Factor Analysis (MOFA), and advanced machine learning algorithms. Measurements and Main ResultsNMF clustering uncovered distinctive protein expression patterns associated with integrin-mediated signaling pathways and immune response mechanisms. Complementarily, MOFA identified latent factors correlating with lung function metrics, highlighting critical molecular pathways involved in integrin cell surface interactions and lipid metabolism regulation. Machine learning-based analysis facilitated the development of a multi-marker panel-comprising IGHV2-70, LysoPC (16:0), and hexadecyl ferulate-which achieved 81.46% accuracy in identifying pulmonary dysfunction cohort. ConclusionsThese findings suggest that alterations in integrin-related signaling networks and dysregulation of lipid metabolism play pivotal roles in mediating the long-term pulmonary consequences of humidifier disinfectant exposure. The proposed multi-marker panel offers significant potential for enhanced risk stratification and timely therapeutic intervention. At a Glance CommentaryO_ST_ABSScientific Knowledge on the SubjectC_ST_ABSExtensive epidemiological evidence has established the causal relationship between humidifier disinfectant exposure and pulmonary dysfunction; however, clinically validated biomarkers for predicting chronic lung disease progression remain limited. Pediatric populations demonstrate unique pathophysiological mechanisms distinct from adults, highlighting the critical necessity for biomarker identification grounded in comprehensive molecular understanding. Despite advances in omics technologies, recent investigations have encountered significant obstacles in achieving deeper mechanistic insights, predominantly attributable to methodological constraints in harmonizing clinical phenotypes with high-dimensional molecular datasets. What This Study Adds to the FieldThis investigation elucidates the fundamental contributions of integrin-mediated signaling cascades and lipid metabolic networks to persistent pulmonary dysfunction following humidifier disinfectant exposure. Our analyses revealed coordinated regulation of integrin signaling pathways and immune response networks through NMF clustering, indicating dynamic temporal evolution of inflammatory responses during chronic disease progression, with temporally distinct molecular signatures identified across discrete observation intervals. Multi-omics factor analysis (MOFA) corroborated integrin pathway dysregulation while additionally uncovering systematic suppression of lipid metabolic processes. Furthermore, machine learning algorithms enabled development of a robust three-component biomarker panel--encompassing IGHV2-70, LysoPC (16:0), and hexadecyl ferulate--demonstrating 81.46% classification accuracy for pulmonary dysfunction phenotypes. Collectively, these findings substantially advance mechanistic understanding of chronic lung injury in vulnerable pediatric cohorts and identify clinically relevant biomarkers with translational potential for risk stratification and therapeutic targeting in clinical practice.

systems biology↗

bioRxiv2025

A TP53 Intron-Derived Peptide Promotes Tumor Survival

During transcription, alternative cleavage and polyadenylation (APA) of transcripts produces mRNAs that differ in their 3 ends. We previously found that leukemia cells cleave and polyadenylate transcripts within introns (intronic APA, IPA) to generate truncated RNA isoforms, which perturb the expression and function of corresponding genes. In addition to protein-coding RNA, we found that leukemia cells express numerous putative long non-coding RNAs generated by IPA, with most uncharacterized. Here, we identify an IPA isoform encoded within intron 1 of the TP53 tumor suppressor gene that is translated into a non-canonical protein termed IPADP1 (IPA-derived protein 1). IPADP1 expression was detected in patient leukemia cells and human blood cancer cell lines. We uncovered an oncogenic role for IPADP1 in enhancing cancer cell survival during drug treatments, as well as promoting tumor formation in vivo. Using proteomic and functional studies, our data suggest that IPADP1 increases cell viability by regulating apoptotic signaling, cell cycle, and DNA damage responses. Furthermore, we observed that the expression of p53-IPA is significantly associated with SF3B1 mutations in leukemia patients, suggesting mechanisms for the genesis of this isoform. Our study demonstrates that an IPA isoform could have a function different from its host gene.

cancer biology↗

bioRxiv2025

Cell-cell communication as underlying principle governing color pattern formation in fishes

The diverse pigmentation patterns of animals are crucial for predation avoidance and behavioral display, yet mechanisms underlying this diversity remain poorly understood. In zebrafish, Turing models have been proposed to explain stripe patterns, but it is unclear if they apply to other fishes. In anemonefish (Amphiprion ocellaris), we identified gja5b, a gene orthologous to zebrafish leopard and encoding a connexin involved in pigment cell communication, as responsible for the Snowflake phenotype. Using CRISPR/Cas9 and transgenesis, we recapitulate the Snowflake phenotype and show expression of gja5b in iridophores. A matching allele was recovered in zebrafish, revealing complementary requirements in both species. Our findings highlight conserved roles of gap junction mediated communication in pigment patterning across divergent teleosts.

developmental biology↗

bioRxiv2025

Rapid CAR Screening and circRNA-driven CAR-NK Cells for Persistent Shed-resistant Immunotherapy

Chimeric antigen receptor (CAR)-based immunotherapies against solid tumors face two major hurdles, the "decoy effect" of shedding antigens that sequester CARs, and the limited persistence of immune effectors within the immunosuppressive tumor microenvironment. Here, we present a mechanistic approach to overcome these barriers by integrating a physiologically relevant screening platform with circular RNA (circRNA) engineering. Unlike conventional screens using immortalized cell lines, we performed rapid functional screening directly in human primary natural killer (NK) cells to identify a novel scFv, CLMS10. Structural modeling revealed that CLMS10 targets a membrane-proximal epitope that overlaps the proteolytic cleavage site, thereby evading inhibition by soluble mesothelin (solMSLN). Furthermore, we demonstrated that circRNA-mediated CAR expression, when codelivered with interleukin-21 (IL-21), confers sufficient stability to withstand the continuous antigen shedding induced by cancer-associated fibroblasts (CAFs), resulting in reduced CAR downregulation. In an in vivo metastatic pancreatic cancer model, IL-21-augmented circCAR-MS10-NK cells exhibited potency comparable to that of lentivirally engineered CAR-NK cells while offering superior manufacturability. Overall, this study establishes a paradigm for generating shed-resistant CAR therapeutics through the strategic integration of epitope-specific functional selection and enhanced RNA stability.

bioengineering↗

bioRxiv2025

Parietal top-down projections balance flexibility and stability in adaptive learning

Rapid behavioral adaptation requires the brain to solve a fundamental computational dilemma: how to flexibly update learned rules while maintaining stable motor performance. This flexibility-stability trade-off is central to cognitive function and artificial intelligence, yet its neural circuit basis is poorly understood. Here, we identify the circuit architecture that coordinates this balance. Using a within-session auditory reversal learning task combined with circuit-specific manipulations in mice, we demonstrate that the posterior parietal cortex (PPC) orchestrates adaptive learning through two parallel, anatomically distinct pathways to the auditory cortex (AC) and inferior colliculus (IC). These two circuits perform a double dissociation of function: the PPC-to-AC circuit facilitates flexible rule updating by encoding dynamic stimulus-outcome contingencies, while the PPC-to-IC circuit preserves stable action execution across changing rules. A feedforward network model further demonstrates that segregated stable and flexible top-down projections are necessary and sufficient for rapid reversal learning. This parallel architecture segregates adaptive and stable computations into distinct circuits, providing a mechanistic framework for cognitive flexibility and offering potential insight into conditions where this balance is disrupted, such as obsessive-compulsive disorder and schizophrenia.

neuroscience↗

bioRxiv2025

Deconstructing the common anteroposterior organisation of adult bilaterian guts

A through-gut is one of the major features of bilaterians. Comparative work among bilaterians has identified common molecular mechanisms during early gut patterning, but the primordial gut later often undergoes different degrees of reorganization in each lineage to form a fully differentiated adult gut with specializations along its anteroposterior (AP) axis. Yet, how the conserved embryonic gut AP pattern relates to the adult guts in diverse bilaterians after metamorphosis is still poorly understood. To unravel the molecular subdivisions of adult guts, we investigated the gut through transcriptomic analyses of five phylogenetically informative species, an annelid, a sea urchin, a hemichordate, a cephalochordate, and a vertebrate. We identified bipartite transcriptional programs defining the AP functional subdivisions. Patterning systems composed of Hox, Parahox, and, surprisingly, other transcription factors (TFs) known to be involved in gut formation in sea urchin larvae are maintained in these adult tissues. Using unbiased analyses, we identified five conserved TF modules corresponding to the AP compartments of the guts that are elaborated or shifted in different species. Our study inferred conserved and modified adult AP patterning modules along bilaterian guts enabling the reconstruction of ancestral bilaterian features with profound implications for the evolution of the bilaterian body plan.

developmental biology↗

bioRxiv2025

Alcohol impacts an fMRI marker of neural inhibition in humans and rodents.

Acute alcohol consumption leads to cognitive and behavioral disinhibition that increase health and social risks, such as traffic fatalities and violence. Although rodent studies have shown that alcohol affects inhibitory neuronal activity, its relevance to humans remains largely unexplored. Here, we used the Hurst exponent--an fMRI-based marker of neural inhibition--to examine alcohols effects in both rats and humans. In rats, acute alcohol administration significantly reduced the cortical Hurst exponent, suggesting a decrease in inhibitory neuronal activity. This reduction was strongly correlated with the spatial distribution of GABAA receptor expression, highlighting the key role of these receptors in mediating alcohols effects. Similarly, in humans, acute alcohol consumption reduced the cortical Hurst exponent, especially in brain regions with high GABAA receptor expression. Our findings provide cross-species in vivo evidence that acute alcohol consumption modulates neural inhibition, offering new insights into the neural mechanisms underlying alcohol-induced behavioral modulation.

neuroscience↗

bioRxiv2025

Blocking CCR2+ Monocyte Infiltration Enhances Neurological Recovery after Subarachnoid Hemorrhage

BACKGROUNDSubarachnoid hemorrhage (SAH) patients mortality rate has been decreasing, but improving survivors prognosis outcome, which impacts patients quality of life, is still limited. An Early Brain Injury (EBI), which is a period of first 72 hours after SAH, is critical phase when resident and infiltrating innate immune cells induce neuroinflammation, deciding the prognosis outcome. While the roles of microglia have been studied, little is known about the role of infiltrating immune cells, especially that of monocytes. We investigated how the absence of monocyte infiltration during EBI may affect SAH outcomes. METHODSUsing Middle cerebral artery (MCA) perforation method, we established Wild type (WT) and C-C Chemokine Receptor type 2 (CCR2) knockout transgenic mice (CCR2-/-) SAH model. Using flow cytometry, we determined differences in immune cell infiltration population. Also, through Cytometric bead array (CBA), we measured inflammatory cytokine level. We performed different behavioral experiments to assess neurological and behavioral recovery and prognosis of SAH. Furthermore, to confirm neuronal cell death severity, immunohistochemistry was performed. We also tested CCR2 antagonists in the early EBI period to see if it impacted WT mices neurological outcome. RESULTSSAH model showed increased infiltration of CD45hi immune cells, mainly Ly6C+ monocyte at 24 hours after SAH, which were nearly abolished in CCR2-/- SAH mice. Increased IL-6 and TNF- cytokine levels in cerebrospinal fluid was significantly reduced as well. Also, better neurological and motor recovery was observed from CCR2-/- SAH mice. Overall neuronal cell death by late EBI period was significantly decreased. Finally, WT SAH mice treated with CCR2 antagonists showed improved neurological outcomes 24 hours after SAH, while showing reduced total infiltrating immune cells and monocytes. CONCLUSIONClassical monocyte infiltration, which occurs via CCR2 signaling, is detrimental for neuroinflammation during EBI of SAH that leads to poor prognosis. CCR2 inhibition could be a potential target for interventional therapeutic strategy. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=66 SRC="FIGDIR/small/644055v1_ufig1.gif" ALT="Figure 1"> View larger version (25K): org.highwire.dtl.DTLVardef@66726eorg.highwire.dtl.DTLVardef@1e2d390org.highwire.dtl.DTLVardef@afa86borg.highwire.dtl.DTLVardef@5a3f85_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical AbstractC_FLOATNO C_FIG

immunology↗

bioRxiv2025

SORDINO for Silent, Sensitive, Specific, and Artifact-Resisting fMRI in awake behaving mice

Blood-oxygenation-level-dependent (BOLD) functional magnetic resonance imaging (fMRI) has revolutionized our understanding of the brain activity landscape, bridging circuit neuroscience in animal models with noninvasive brain mapping in humans. This immensely utilized technique, however, faces challenges such as acoustic noise, electromagnetic interference, motion artifacts, magnetic-field inhomogeneity, and limitations in sensitivity and specificity. Here, we introduce Steady-state On-the-Ramp Detection of INduction-decay with Oversampling (SORDINO), a transformative fMRI technique that addresses these challenges by maintaining a constant total gradient amplitude while acquiring data during continuously changing gradient direction. When benchmarked against conventional fMRI on a 9.4T system, SORDINO is silent, sensitive, specific, and resistant to motion and susceptibility artifacts. SORDINO offers superior compatibility with multimodal experiments and carries novel contrast mechanisms distinct from BOLD. It also enables brain-wide activity and connectivity mapping in awake, behaving mice, overcoming stress- and motion-related confounds that are among the most challenging barriers in current animal fMRI studies.

neuroscience↗

bioRxiv2025

Alternative polyadenylation regulates human urothelial differentiation

The urothelium is stratified into progenitor basal cells, intermediate cells, and terminally differentiated umbrella cells. Proper renewal of umbrella cells is necessary for maintaining urinary tract barrier integrity. To investigate whether mRNA alternative cleavage and polyadenylation (APA) regulates urothelial differentiation, we developed a single-cell polyadenylation site usage (scPASU) computational pipeline to map cell state-specific polyadenylation sites in single-cell RNA-seq data from 13,544 urothelial cells. Leveraging single-cell spatial imaging, we directly visualized APA events in situ, revealing their spatial specificity within the adult human ureter. APA shaped urothelial differentiation, independent of gene expression changes. Furthermore, key APA-regulated genes shared conserved motifs in their 3 UTRs, often containing Alu elements, suggesting a potential mechanism regulating poly(A) site selection. Our study establishes APA as a driver of urothelial transcriptome diversity.

systems biology↗

bioRxiv2025

Insights into the Evolution of Ancient Shark and Ray Sex Chromosomes

While sex-determining mechanisms have been extensively characterized in many vertebrates, they have not been explored in chondrichthyan fishes until relatively recently. In the present study, we used high-quality whole genome reference assemblies to examine the putative sex chromosomes of 14 elasmobranch species spanning nine orders. We describe four newly assembled reference genomes belonging to the white shark Carcharodon carcharias, the Atlantic stingray Hypanus sabinus, the smalltooth sawfish Pristis pectinata, and the zebra shark Stegostoma tigrinum. We conducted sex chromosome identification and verification using short-read sequence data collected for multiple individuals for three of the species. This revealed putative pseudoautosomal regions (PARs) and, in one instance, a candidate sex chromosome reassignment. A synteny analysis revealed an ancient and shared origin of the chromosomes within elasmobranchs considerably older than any previously proposed scenario, and a potential candidate gene involved in sex determination shared across all examined species. The synteny analysis also revealed a historical fusion and the formation of neo-Y chromosomes between two myliobatiform species. Our results show that there has been strong conservation and homology of the X chromosomes among elasmobranchs in spite of their varied features and different evolutionary histories.

evolutionary biology↗

bioRxiv2024

LAG3 marks activated but hyporesponsive NK cells.

Natural Killer (NK) cells are critical for immunosurveillance yet become dysfunctional in contexts such as chronic stimulation by viral infections or cancer. This phenomenon is similar to T cell exhaustion but less well characterized, which limits therapeutic interventions. As shown for T cells, NK cells often display an increased expression of immune checkpoint proteins (ICP) following chronic stimulation, and ICP blockade therapies are currently being explored for several cancer types, which have remarkable patient benefits. Nevertheless, the nature of ICP expression in NK cells is still poorly documented. In this study, we aimed to identify the conditions that lead to and the phenotype of immune checkpoint LAG3 (Lymphocyte-activation gene 3) expressing NK cells. Using various experimental models, we found that LAG3 is expressed by murine NK cells upon activation in different contexts, including in response to cancer and acute viral infections. LAG3 marks a subset of immature, proliferating and activated cells, which, despite activation, have a reduced capacity to respond to a broad range of stimuli. Further characterization also revealed that LAG3+ NK cells exhibit a transcriptional signature similar to that of exhausted CD8+ T cells. Taken together, our results support the use of LAG3 as a marker of dysfunctional NK cells across diverse chronic and acute inflammatory conditions.

immunology↗

bioRxiv2024

Downregulation of O-GlcNAcylation enhances etoposide-induced p53-mediated apoptosis in HepG2 human liver cancer cells

Etoposide, an anticancer drug that inhibits topoisomerase II, is commonly used in combination chemotherapy. However, the impact of O-GlcNAcylation regulation on etoposides anticancer effects has rarely been investigated. This study evaluated the effect of etoposide on cellular O-GlcNAcylation and whether modulating this process enhances etoposide-induced apoptosis. O-GlcNAc expression was measured after 24 h of etoposide treatment, and the effect of O-GlcNAc transferase (OGT) inhibition by OSMI-1 on etoposides anticancer activity in HepG2 human liver cancer cells was quantitatively analyzed. Additionally, molecular analyses were used to confirm that the observed effects were mediated by p53-induced apoptosis. Etoposide reduced O-GlcNAcylation in a dose-dependent manner without directly interacting with OGT. Cotreatment with 20 M of OSMI-1 lowered the IC50 value for cell viability by approximately 1.64-fold to 60.68 M and increased the EC50 value for cytotoxicity by around 4.07-fold to 43.41 M. Furthermore, this synergistic effect was linked to the activation of the p53/caspase-3/PARP1 pathway. These findings suggest that downregulating O-GlcNAcylation may enhance the efficacy of etoposide-based chemotherapy and help overcome tumor resistance. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/626030v2_ufig1.gif" ALT="Figure 1"> View larger version (59K): org.highwire.dtl.DTLVardef@3cb205org.highwire.dtl.DTLVardef@cb686forg.highwire.dtl.DTLVardef@356662org.highwire.dtl.DTLVardef@1d4dc40_HPS_FORMAT_FIGEXP M_FIG Etoposide, a topoisomerase II inhibitor, reduces O-GlcNAcylation in HepG2 liver cancer cells. Further inhibition of O-GlcNAc transferase by OSMI-1 enhanced etoposide-induced apoptosis, lowering the IC50 for viability and increasing the EC50 for cytotoxicity. This synergy was mediated by the p53, caspase-3/7, PARP1 pathway, suggesting that targeting O-GlcNAcylation may improve etoposide efficacy. C_FIG

molecular biology↗

bioRxiv2024

Hijacking and recording intracellular RNAs in human cells using eukaryotic reprogrammed tracrRNAs

Recording intracellular RNA expression events is critical for understanding cell states and biological processes, but no method without responsive promoters is available in mammalian cells. Here, we determined the sequence formula of eukaryotic reprogrammed tracrRNA, named euRptr, which can hijack intracellular RNAs to make a complex with CRISPR-associated tools. By leveraging the programmability of euRptr, we devised the system "CHEETAH" to directly capture and record intracellular RNAs in human cells. We validated that CHEETAH induces self-editing by hijacking endogenous mRNAs, that CHEETAH selectively records different viral RNA fragments on a DNA reporter using base editors with a shared-euRptr, and that CHEETAH enables multiplexed, time-resolved recording of viral RNAs on a DNA Tape using prime editors, providing a new avenue for investigating intracellular RNA in eukaryotes.

genetics↗

bioRxiv2024

Bystander base editing interferes with visual function restoration in Leber congenital amaurosis

Base editors (BEs) have emerged as a powerful tool for gene correction with high activity. However, bystander base editing, a byproduct of BEs, presents challenges for precise editing. Here, we investigated the effects of bystander edits on phenotypic restoration in the context of Leber congenital amaurosis (LCA), a hereditary retinal disorder, as a therapeutic model. We observed that in rd12 of LCA model mice, the highest editing activity version of an adenine base editors (ABEs), ABE8e, generated substantial bystander editing, resulting in missense mutations despite RPE65 expression, preventing restoration of visual function. Through AlphaFold-based mutational scanning and molecular dynamics simulations, we identified that the ABE8e-driven L43P mutation disrupts RPE65 structure and function. Our findings underscore the need for more stringent requirements in developing precise BEs for future clinical applications.

genetics↗

bioRxiv2024

Rapid cyclic stretching induces synthetic, proinflammatory phenotypes in cultured human intestinal smooth muscle, with the potential to alter signaling to adjacent bowel cells

Background and AimsBowel smooth muscle experiences mechanical stress constantly during normal function, and pathologic mechanical stressors in disease states. We tested the hypothesis that pathologic mechanical stress could alter transcription to induce smooth muscle phenotypic class switching. MethodsPrimary human intestinal smooth muscle cells (HISMCs), seeded on electrospun aligned poly-{varepsilon}-caprolactone nano-fibrous scaffolds, were subjected to pathologic, high frequency (1 Hz) uniaxial 3% cyclic stretch (loaded) or kept unloaded in culture for 6 hours. Total RNA sequencing, qRT-PCR, and quantitative immunohistochemistry defined loading-induced changes in gene expression. NicheNet predicted how differentially expressed genes might impact HISMCs and other bowel cells. ResultsLoading induced differential expression of 4537 genes in HISMCs. Loaded HISMCs had a less contractile phenotype, with increased expression of synthetic SMC genes, proinflammatory cytokines, and altered expression of axon guidance molecules, growth factors and morphogens. Many differentially expressed genes encode secreted ligands that could act cell-autonomously on smooth muscle and on other cells in the bowel wall. DiscussionHISMCs demonstrate remarkably rapid phenotypic plasticity in response to mechanical stress that may convert contractile HISMCs into proliferative, fibroblast-like cells or proinflammatory cells. These mechanical stress-induced changes in HISMC gene expression may be relevant for human bowel disease.

bioengineering↗