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Biology subjects

Chen, H.-H.

Publications and source records attributed to Chen, H.-H..

7 recordsLinked to original sources

Integrated Proteo-Metabolomics of Urinary Extracellular Vesicles Reveals Early Molecular Divergence and Temporal Pathogenesis of Sepsis-Associated AKI

BackgroundSepsis-associated acute kidney injury (S-AKI) is a major contributor to morbidity and mortality in critically ill patients. However, the molecular mechanisms underlying its temporal progression remain poorly understood because conventional biomarkers primarily reflect renal dysfunction rather than disease pathogenesis. Urinary extracellular vesicles (uEVs), which carry kidney-derived molecular cargo, provide a promising platform for monitoring renal-specific biological alterations during disease progression. MethodsWe conducted a longitudinal multi-omics study of uEVs collected from 81 patients with sepsis, including 48 patients with S-AKI and 33 sepsis-only controls. Patients were randomly assigned to a discovery cohort (n = 52) and an independent validation cohort (n = 29). Urine samples were collected at Day 1, Day 4, and Day 8 after AKI diagnosis. High-resolution proteomic and metabolomic profiling was performed to characterize temporal molecular alterations. Enriched pathways identified in the discovery cohort were evaluated in the validation cohort using pathway-level concordance analysis. ResultsComparative analysis between S-AKI and sepsis-only patients identified distinct stage-specific molecular alterations throughout disease progression. At the early stage (Day 1), validated pathways included complement and coagulation cascades, ferroptosis, HIF-1 signaling, sphingolipid metabolism, and arachidonic acid metabolism, highlighting coordinated inflammatory, hypoxic, and lipid metabolic responses. During the mid-stage (Day 4), persistent activation of complement and coagulation cascades, ferroptosis, and HIF-1 signaling was accompanied by metabolic reprogramming involving alanine, aspartate and glutamate metabolism and tyrosine metabolism. Although limited sample availability reduced statistical power at Day 8, phenylalanine metabolism remained validated in the metabolomic analysis, suggesting persistent metabolic dysregulation during late-stage disease progression. ConclusionsThis study provides the first longitudinal, independently validated multi-omics characterization of human uEVs in S-AKI. By integrating proteomic and metabolomic profiling, we reveal the temporal evolution of renal-specific molecular pathways from early inflammatory and hypoxic responses to subsequent metabolic reprogramming. These findings establish uEV-based multi-omics as a promising strategy for molecular phenotyping of S-AKI beyond conventional clinical biomarkers and provide a valuable resource for future biomarker discovery and therapeutic target identification.

biochemistry↗

The Taiwan Precision Medicine Initiative: A Cohort for Large-Scale Studies

The Taiwan Precision Medicine Initiative (TPMI), a project initiated by the Academia Sinica in collaboration with 16 major medical centers around Taiwan, has recruited 565,390 participants who consented to provide DNA samples for genetic profiling and grant access to their electronic medical records (EMR) for studies to develop precision medicine. Access to the EMR is both retrospective and prospective, allowing researchers to conduct prospective studies over time. Genetic profiling is done with population-optimized SNP arrays for the Han Chinese populations that enable genetic analyses such as genome-wide association, phenome-wide association, and polygenic risk score studies to evaluate common disease risk and pharmacogenetic response. Furthermore, the TPMI participants agree to be contacted for future research opportunities related to their genetic risks and receive personalized genetic risk profiles with health management recommendations. TPMI has established the TPMI Data Access Platform (TDAP), a central database and analysis platform that both safeguards the security of the data and facilitates academic research. The TPMI is the largest non-European cohort that merges genetic profiles with EMR in the world. With a cohort that can be followed over time, it can be utilized to validate genetic risk prediction models, conduct clinical trials to show the efficacy of risk-based health management, and optimize health policies based on genetic risks. In this report, we describe the TPMI study design, the population and genetic characteristics of the TPMI cohort, and the power it provides to conduct crucial studies in developing precision medicine on a population and personal level. As Han Chinese represent almost 20% of the worlds population, the results of TPMI studies will benefit >1.4 billion people around the world and serve as a model for developing population-based precision medicine.

genetics↗

Overloading And unpacKing (OAK) - droplet-based combinatorial indexing for ultra-high throughput single-cell multiomic profiling

Multiomic profiling of single cells by sequencing is a powerful technique for investigating cellular diversity in complex biological systems. Although the existing droplet-based microfluidic methods have advanced single-cell sequencing, they produce a plethora of cell-free droplets and underutilize barcoding capacities due to their low cell concentration prerequisites. Meanwhile, combinatorial indexing on microplates can index cells in a more effective way; however, it requires time-consuming and laborious protocols involving multiple splitting and pooling steps. Addressing these constraints, we have developed "Overloading And unpacKing" (OAK). With reduced labor intensity, OAK can provide cost-effective multiomic profiling for hundreds of thousands of cells, offering detection sensitivity on par with commercial droplet-based methods. To demonstrate OAKs versatility, we conducted single-cell RNA sequencing (scRNA-Seq) as well as joint single-nucleus RNA sequencing (snRNA-Seq) and single-nucleus Assay for Transposase Accessible Chromatin with sequencing (snATAC-Seq) using cell lines. We further showcased OAKs performance on more complex samples, including in vitro differentiated bronchial epithelial cells and primary retinal tissues. Finally, we examined transcriptomic responses of 408,000 melanoma cells across around 1,000 starting lineages over a 90-day treatment with a RAF inhibitor, belvarafenib. We discovered a rare cell population (0.12%) that underwent a sequence of transcriptomic changes, resulting in belvarafenib resistance. Ultra-high throughput, broad compatibility with diverse molecular modalities, high detection sensitivity, and simplified experimental procedures distinguish OAK from previous methods, and render OAK a powerful tool for large-scale analysis of molecular signatures, even for rare cells.

molecular biology↗

Nuclear receptor interaction protein (NRIP) as a novel actin-binding protein involved in invadosome formation for myoblast fusion

To investigate the role of nuclear receptor interaction protein (NRIP) in myoblast fusion, both the primary myoblasts from muscle-specific NRIP-knockout mice and NRIP-null C2C12 cells (KO19 cells) exhibited a significant deficit in the fusion index during myogenesis; on the other hand, overexpressed NRIP in KO19 cells could rescue myotube formation. Furthermore, NRIP was found to interact with actin directly and reciprocally that is an invadosome component for myoblast fusion. Endogenous NRIP colocalized with components of invadosome such as F-actin, Tks5, and cortactin at the tips of cells during C2C12 differentiation, and exogenous NRIP was enriched with actin at the tip of attacking cells during myogenic fusion, implying that NRIP is a novel invadosome component. Using time-lapse microscopy and cell-cell fusion assays further confirmed NRIP directly participates in cell fusion through actin. Moreover, to map the domain of NRIP-actin binding, NRIP interacted with actin either through WD40 domains directly for binding or indirectly through the IQ domain for -actinin 2 binding with actin. NRIP with actin binding was strongly correlated with invadosome formation and myotube fusion. Collectively, NRIP acts as a novel actin-binding protein through its WD40 or the IQ to form invadosomes that trigger myoblast fusion.

cell biology↗

Human-specific enrichment of schizophrenia risk-genes in callosal neurons of the developing neocortex

Human genetic studies have provided a wealth of information on genetic risk factors associated with neuropsychiatric diseases. However, whether different brain cell types are differentially affected in disease states and when in their development and maturation alterations occur is still poorly understood. Here we generated a longitudinal transcriptional map of excitatory projection neuron (PN) and inhibitory interneuron (IN) subtypes of the cerebral cortex, across a timeline of mouse embryonic and postnatal development, as well as fetal human cortex and human cortical organoids. We found that three types of gene signatures uniquely defined each cortical neuronal subtype: dynamic (developmental), adult (terminal), and constitutive (stable), with individual neuronal subtypes varying in the degree of similarity of their signatures between species. In particular, human callosal projection neurons (CPN) displayed the greatest species divergence, with molecular signatures highly enriched for non-coding, human-specific RNAs. Evaluating the association of neuronal class-specific signatures with neuropsychiatric disease risk genes using linkage disequilibrium score regression showed that schizophrenia risk genes were enriched in CPN identity signatures from human but not mouse cortex. Human cortical organoids confirmed the association with excitatory projection neurons. The data indicate that risk gene enrichment is both species- and cell type-specific. Our study reveals molecular determinants of cortical neuron diversification and identifies human callosal projection neurons as the most species-divergent population and a potentially vulnerable neuronal class in schizophrenia.

developmental biology↗

FIN-Seq: Transcriptional profiling of specific cell types in frozen archived tissue from the human central nervous system

Thousands of frozen, archived tissues from postmortem human central nervous system (CNS) are currently available in brain banks. As single cell and single nucleus technologies are beginning to elucidate the cellular diversity present within the human CNS, it is becoming clear that transcriptional analysis of the human CNS requires cell type specificity. Single cell and single nucleus RNA profiling provide one avenue to decipher this heterogeneity. An alternative, complementary approach is to profile isolated, pre-defined cell types and use methods that can be applied to many archived human tissue samples. Here, we developed FIN-Seq (Frozen Immunolabeled Nuclei Sequencing), a method that accomplishes these goals. FIN-Seq uses immunohisto-chemical isolation of nuclei of specific cell types from frozen human tissue, followed by RNA-Sequencing. We applied this method to frozen postmortem samples of human cerebral cortex and retina and were able to identify transcripts, including low abundance transcripts, in specific cell types.

neuroscience↗

An allele-specific functional SNP associated with two autoimmune diseases modulates IRF5 expression by long-range chromatin loop formation

Both Systemic Lupus Erythematosus (SLE) and Systemic Sclerosis (SSc) are autoimmune diseases sharing similar genetic backgrounds. Genome-wide association studies (GWASs) have constantly disclosed numerous genetic variants conferring to both disease risks at 7q32.1, but the functional mechanisms underlying them are still largely unknown. Through combining fine-mapping and functional epigenomic analyses, we prioritized a potential independent functional SNP (rs13239597) within TNPO3 promoter region, residing in a putative enhancer element. Functional analysis integrating expression quantitative trait locus (eQTL) and high-throughput chromatin interaction (Hi-C) demonstrated that IRF5 is the distal target gene (~118kb) of rs13239597, which is a key regulator of pathogenic autoantibody dysregulation increased risk of both SLE and SSc. We experimentally validated the long-range chromatin interactions between rs13239597 and IRF5 using chromosome conformation capture (3C) assay. We further demonstrated that rs13239597-A acted as an allele-specific enhancer regulating IRF5 expression, independently of TNPO3 by using dual-luciferase reporter assays and CRISPR-Cas9. Particularly, the transcription factor EVI1 could preferentially bind to rs13239597-A allele and increase the enhancer activity to regulate IRF5 expression. Taken together, our results uncovered the mechanistic insight connecting between a noncoding functional variant with a distal immunologically pathogenic gene IRF5, which might obligate in understanding the complex genetic architectures of SLE and SSc pathogenesis.

genetics↗