Biology subjects

Lee, J. H.

Publications and source records attributed to Lee, J. H..

At least 91 records · Page 5Linked to original sources

bioRxiv2022

A Phytophthora nucleolar effector, Pi23226, targets to host ribosome biogenesis for necrotrophic cell death

Pathogen effectors target diverse subcellular organelles to manipulate the plant immune system. Although nucleolus has been emerged as a stress marker, and several effectors are localized in the nucleolus, the roles of nucleolar-targeted effectors remain elusive. In this study, we showed Phytophthora infestans infection of Nicotiana benthamiana results in nucleolar inflation during the transition from biotrophic to necrotrophic phase. Multiple P. infestans effectors were localized in the nucleolus: Pi23226 induced cell death in Nicotiana benthamiana and nucleolar inflation similar to that observed in the necrotrophic stage of infection, whereas its homolog Pi23015 and a deletion mutant (Pi23226{Delta}C) did not induce cell death or affect nucleolar size. RNA immunoprecipitation and iCLIP-seq analysis indicated that Pi23226 bound to the 3'-end of 25S rRNA precursors, resulting in the accumulation of unprocessed 27S pre-rRNAs. The nucleolar stress marker NAC082 was strongly upregulated under Pi23226-expressing conditions. Pi23226 subsequently inhibited global protein translation in host cells by interacting with ribosomes. Pi23226 enhanced P. infestans pathogenicity, indicating that Pi23226-induced ribosome malfunction and cell death was beneficial for pathogenesis in the host. Our results provide evidence for the molecular mechanism underlying RNA-binding effector activity in host ribosome biogenesis, and lead to new insights into the nucleolar action of effectors in pathogenesis.

plant biology↗

bioRxiv2022

High-dimensional and spatial analysis reveals immune landscape dependent progression in cutaneous squamous cell carcinoma

PurposeThe tumour immune microenvironment impacts the biological behaviour of the tumour but its effect on clinical outcomes in head and neck cutaneous squamous cell carcinomas (HNcSCC) is largely unknown. Experimental DesignWe compared the immune milieu of high-risk HNcSCC that never progressed to metastasis with those that metastasised using multi-parameter imaging mass cytometry. The cohort included both immunosuppressed patients (IS) and patients with an absence of clinical immune-suppression (ACIS). Spatial analyses were used to identify cellular interactions that were associated with tumour behaviour. ResultsNon-progressing primary HNcSCC were characterised by higher CD8+ and CD4+ T cell responses, including numerically increased Regulatory T cells. By contrast, primary lesions from HNcSCC patients who progressed were largely devoid of T cells with lower numbers of innate immune cells and increased expression of checkpoint receptors and in the metastatic lesions were characterised by an accumulation of B cells. Spatial analysis reveals multiple cellular interactions associated with non-progressing primary tumours that were distinct in primary tumours of disease progressing patients. Cellular regional analysis of the tumour microenvironment also shows squamous cell-enriched tumour regions associated with primary non-progressing tumours. ConclusionsEffective responses from both CD8+ and CD4+ T cells in the tumour microenvironment are essential for immune control of primary HNcSCC. Our findings indicate that the early events that shape the immune responses in primary tumours dictate progression and disease outcomes in HNcSCC. Translational RelevanceThe ability to predict metastatic tumour progression at the time of initial diagnosis of primary HNcSCC could tailor personalised medical care including disease surveillance strategies and identifying patients who will benefit most from adjuvant therapy. One Sentence SummaryThe immune landscape of high-risk cutaneous squamous cell carcinoma differs in tumours that never progress compared to those that progress to metastasis.

pathology↗

bioRxiv2022

Gallbladder adenocarcinomas undergo subclonal diversification and selection from precancerous lesions to metastatic tumors

We aimed to elucidate the evolutionary trajectories of gallbladder adenocarcinoma (GBAC) using multi-regional and longitudinal tumor samples. Using whole-exome sequencing data, we constructed phylogenetic trees in each patient, and analyzed mutational signatures. A total of 11 patients including 2 rapid autopsy cases were enrolled. The most frequently altered gene in primary tumors was ERBB2 (54.5%), followed by TP53 (45.5%), and FBXW7 (27.3%). Most mutations in frequently altered genes in primary tumors were detectable in concurrent precancerous lesions (biliary intraepithelial neoplasia, BilIN), but some of them were subclonal. Subclonal diversity was common in BilIN (n=4). However, among subclones in BilIN, a certain subclone commonly shrank in concurrent primary tumors. In addition, selected subclones underwent linear and branching evolution, maintaining subclonal diversity. In combined analysis with metastatic tumors (n=11), branching evolution was identified in 9 (81.8%) patients. Of these, 8 patients (88.9%) had a total of 11 subclones expanded at least 7-fold during metastasis. These subclones harbored putative metastasis-driving mutations in tumor suppressor genes such as SMAD4, ROBO1, and DICER1. In mutational signature analysis, 6 mutational signatures were identified: 1, 3, 7, 13, 22, and 24 (cosine similarity >0.9). Signatures 1 (age) and 13 (APOBEC) decreased during metastasis while signatures 22 (aristolochic acid) and 24 (aflatoxin) were relatively highlighted. Subclonal diversity arose early in precancerous lesions and the clonal selection was a common event during malignant transformation in GBAC. However, selected cancer clones continued to evolve and thus maintained subclonal diversity in metastatic tumors.

genetics↗

bioRxiv2022

Cisplatin neurotoxicity targets specific subpopulations and K+ channels in tyrosine-hydroxylase positive dorsal root ganglia neurons

Among the features of cisplatin chemotherapy-induced peripheral neuropathy are chronic pain and innocuous mechanical hypersensitivity. The complete etiology of the latter remains unknown. Here, we show that cisplatin targets a heterogeneous population of tyrosine hydroxylase-positive (TH+) primary afferent dorsal root ganglion neurons (DRGNs) within the primary afferent dorsal root ganglia in mice, determined using single-cell transcriptome and electrophysiological analyses. TH+ DRGNs regulate innocuous mechanical sensation through C-low threshold mechanoreceptors. A differential assessment of wild-type and vitamin E deficient TH+ DRGNs revealed heterogeneity and specific functional phenotypes. The TH+ DRGNs comprise; fast-adapting eliciting one action potential (AP; 1-AP), moderately-adapting ([≥] 2-APs), in responses to square-pulse current injection, and spontaneously firing (SF). Cisplatin increased the input resistance and AP frequency but reduced the temporal coding feature of 1-AP and [≥] 2-APs neurons. By contrast, cisplatin has no measurable effect on the SF neurons. Vitamin E reduced the cisplatin-mediated increased excitability, but did not improve the TH+ neuron temporal coding properties. Cisplatin mediates its effect by targeting outward K+ current, likely carried by through K2P18.1 (Kcnk18), discovered through the differential transcriptome studies and heterologous expression. Studies show a potential new cellular target for chemotherapy-induced peripheral neuropathy and implicate the possible neuroprotective effects of vitamin E in cisplatin chemotherapy.

neuroscience↗

bioRxiv2021

Long-lasting germinal center responses to a priming immunization with continuous proliferation and somatic mutation

Germinal centers (GCs) are the engines of antibody evolution. Using HIV Env protein immunogen priming in rhesus monkeys (RM) followed by a long period without further immunization, we demonstrate GC B cells (BGC) lasted at least 6 months (29 weeks), all the while maintaining rapid proliferation. A 186-fold BGC cell increase was present by week 10 compared to a conventional immunization. Single cell transcriptional profiling revealed that both light zone and dark zone GC states were sustained throughout the 6 months. Antibody somatic hypermutation (SHM) of BGC cells continued to accumulate throughout the 29 week priming period, with evidence of selective pressure. Additionally, Env-binding BGC cells were still 49-fold above baseline 29 weeks after immunization, suggesting that they could be active for significantly longer periods of time. High titers of HIV neutralizing antibodies were generated after a single booster immunization. Fully glycosylated HIV trimer protein is a complex antigen, posing significant immunodominance challenges for B cells, among other difficulties. Memory B cells (BMem) generated under these long priming conditions had higher levels of SHM, and both BMem cells and antibodies were more likely to recognize non-immunodominant epitopes. Numerous BGC cell lineage phylogenies spanning the >6-month GC period were identified, demonstrating continuous GC activity and selection for at least 191 days, with no additional antigen exposure. A long prime, adjuvanted, slow delivery (12-day) immunization approach holds promise for difficult vaccine targets, and suggests that patience can have great value for tuning GCs to maximize antibody responses.

immunology↗

bioRxiv2021

Deep Learning-based Automated Rare Sperm Identification from Testes Biopsies

Non-obstructive azoospermia (NOA), the most severe form of male infertility, is currently treated using microsurgical sperm extraction (microTESE) to retrieve sperm cells for in vitro fertilization via intracytoplasmic sperm injection (IVF-ICSI). The success rate of this procedure for NOA patients is currently limited by the ability of andrologists to identify a few rare sperm cells among millions of background testis cells. To improve this success rate, we developed a convolution neural network (CNN) to detect rare sperm from low-resolution microscopy images of microTESE samples. Our CNN uses the U-Net architecture to perform pixel-based classification on image patches from brightfield microscopy, which is followed by morphological analysis to detect individual sperm instances. This CNN is trained using microscopy images of fluorescently labeled sperm, which is fixed to eliminate their motility, and doped into testis biopsies obtained from NOA patients. We initially tested this algorithm using purified sperm samples at different imaging magnifications in order to determine the upper bounds of performance. We then tested this algorithm by doping rare sperm cells into testis biopsy samples from NOA patients and found a sperm detection F1 score of 85.2%. These results demonstrate the potential to use automated microscopy to dramatically increase the amount of testis biopsy tissue that could be comprehensively examined, which greatly increases the chance of finding rare viable sperm, and thereby increases the success rates of IVF-ICSI for couples with NOA.

bioengineering↗

bioRxiv2021

Use of a graph neural network to the weighted gene co-expression network analysis of Korean native cattle

In the general framework of the weighted gene co-expression network analysis (WGCNA), a hierarchical clustering algorithm is commonly used to module definition. However, hierarchical clustering depends strongly on the topological overlap measure. In other words, this algorithm may assign two genes with low topological overlap to different modules even though their expression patterns are similar. Here, a novel gene module clustering algorithm for WGCNA is proposed. We develop a gene module clustering network (gmcNet), which simultaneously addresses single-level expression and topological overlap measure. The proposed gmcNet includes a "co-expression pattern recognizer" (CEPR) and "module classifier". The CEPR incorporates expression features of single genes into the topological features of co-expressed ones. Given this CEPR-embedded feature, the module classifier computes module assignment probabilities. We validated gmcNet performance using 4,976 genes from 20 native Korean cattle. We observed that the CEPR generates more robust features than single-level expression or topological overlap measure. Given the CEPR-embedded feature, gmcNet achieved the best performance in terms of modularity (0.261) and the differentially expressed signal (27.739) compared with other clustering methods tested. Furthermore, gmcNet detected some interesting biological functionalities for carcass weight, backfat thickness, intramuscular fat, and beef tenderness of Korean native cattle. Therefore, gmcNet is a useful framework for WGCNA module clustering. Author summaryA graph neural network is a good alternative algorithm for WGCNA module clustering. Even though the graph-based learning methods have been widely applied in bioinformatics, most studies on WGCNA did not use graph neural network for module clustering. In addition, existing methods depend on topological overlap measure of gene pairs. This can degrade similarity of expression not only between modules, but also within module. On the other hand, the proposed gmcNet, which works similar to message-passing operation of graph neural network, simultaneously addresses single-level expression and topological overlap measure. We observed the higher performance of gmcNet comparing to existing methods for WGCNA module clustering. To adopt gmcNet as clustering algorithm of WGCNA, it remains future research issues to add noise filtering and optimal k search on gmcNet. This further research will extend our proposed method to be a useful module clustering algorithm in WGCNA. Furthermore, our findings will be of interest to computational biologists since the studies using graph neural networks to WGCNA are still rare.

bioinformatics↗

bioRxiv2021

Mechanically active integrins direct cytotoxic secretion at the immune synapse

The secretory output of cell-cell interfaces must be tightly controlled in space and time to ensure functional efficacy. This is particularly true for the cytotoxic immune synapse (IS), the stereotyped junction formed between a cytotoxic lymphocyte and the infected or transformed target cell it aims to destroy1. Cytotoxic lymphocytes kill their targets by channeling a mixture of granzyme proteases and the pore forming protein perforin directly into the IS2, 3. The synaptic secretion of these toxic molecules constrains their deleterious effects to the target cell alone, thereby protecting innocent bystander cells in the surrounding tissue from collateral damage. Despite the importance of this process for immune specificity, the molecular and cellular mechanisms that establish secretory sites within the IS remain poorly understood. Here, we identified an essential role for integrin mechanotransduction in cytotoxic secretion using a combination of single cell biophysical measurements, ligand micropatterning, and functional assays. Upon ligand-binding, the L{beta}2 integrin LFA-1 functioned as a spatial cue, attracting lytic granules containing perforin and granzyme and inducing their fusion at closely adjacent sites within the synaptic membrane. LFA-1 molecules were subjected to pulling forces within these secretory domains, and genetic or pharmacological suppression of these forces abrogated cytotoxicity. We conclude that lymphocytes employ an integrin-dependent mechanical checkpoint to enhance both the potency and the security of their cytotoxic output.

immunology↗

bioRxiv2021

Multi-organ analysis of low-level somatic mosaicism reveals stage- and tissue-specific mutational features in human development

Most somatic mutations arising during normal development present as low-level in single or multiple tissues depending on the developmental stage and affected organs1-4. However, it remains unclear how the human developmental stages or mutation-carrying organs affect somatic mutations features. Here, we performed a systemic and comprehensive analysis of low-level somatic mutations using deep whole-exome sequencing (WES; average read depth: [~]500x) of 498 multiple organ tissues with matched controls from 190 individuals. We found that early-stage mutations shared between multiple organs are lower in number but showed higher allele frequencies than late-stage mutations [0.54 vs. 5.83 variants per individual: 6.17% vs. 1.5% variant allele frequency (VAF)] along with less nonsynonymous mutations and lower functional impacts. Additionally, early- and late-stage mutations had unique mutational signatures distinct from tumor-originate mutations. Compared with early-stage mutations presenting a clock-like signature across all studied organs or tissues, late-stage mutations show organ, tissue, and cell-type specificity in mutation count, VAFs, and mutational signatures. In particular, analysis of brain somatic mutations shows bimodal occurrence and temporal-lobe-specific mutational signatures. These findings provide new insight into the features of somatic mosaicisms dependent on developmental stages and brain regions.

genomics↗

bioRxiv2021

Intrinsic mechanical sensitivity of auditory neurons as a contributor to sound-driven neural activity

Mechanosensation - by which mechanical stimuli are converted into a neuronal signal - is the basis for the sensory systems of hearing, balance, and touch. Mechanosensation is unmatched in speed and its diverse range of sensitivities, reaching its highest temporal limits with the sense of hearing; however, hair cells (HCs) and the auditory nerve (AN) serve as obligatory bottlenecks for sounds to engage the brain. Like other sensory neurons, auditory neurons use the canonical pathway for neurotransmission and millisecond-duration action potentials (APs). How the auditory system utilizes the relatively slow transmission mechanisms to achieve ultrafast speed and high audio-frequency hearing remains an enigma. Here, we address this paradox and report that the AN is mechanically sensitive, and minute mechanical displacement profoundly affects its response properties. Sound-mimicking sinusoidal mechanical and electrical current stimuli affect phase-locked responses. In a phase-dependent manner, the two stimuli can also evoke suppressive responses. We propose that mechanical sensitivity interacts with synaptic responses to shape responses in the AN, including frequency tuning and temporal phase-locking. The combination of neurotransmission and mechanical sensation to control spike patterns gives the AN a secondary receptor role, an emerging theme in primary neuronal functions.

neuroscience↗

bioRxiv2021

Capacity to erase gene occlusion is a defining feature distinguishing naive from primed pluripotency

Pluripotent stem cells can exist in either the naive state representing a developmental blank slate or the downstream primed state poised for differentiation. Currently, known differences between these two states are mostly phenomenological, and none can adequately explain why the two states should differ in developmental priming. Gene occlusion is a mode of epigenetic inactivation that renders genes unresponsive to their cognate transcriptional activators. It plays a crucial role in lineage restriction. Here, we report that a defining feature distinguishing the two pluripotent states lies in the ability of naive but not primed cells to erase occlusion. This "deocclusion" capacity requires Esrrb, a gene expressed only in the naive but not primed state. Notably, Esrrb silencing in the primed state is itself due to occlusion. Collectively, our data argue that the Esrrb-dependent deocclusion capacity in naive cells is key for sustaining naive pluripotency, and the loss of this capacity in the primed state via the occlusion of Esrrb poises cells for differentiation.

molecular biology↗

bioRxiv2021

Application of an integrated computational antibody engineering platform to design SARS-CoV-2 neutralizers

As the COVID-19 pandemic continues to spread, hundreds of new initiatives including studies on existing medicines are running to fight the disease. To deliver a potentially immediate and lasting treatment to current and emerging SARS-CoV-2 variants, new collaborations and ways of sharing are required to create as many paths forward as possible. Here we leverage our expertise in computational antibody engineering to rationally design/optimize three previously reported SARS-CoV neutralizing antibodies and share our proposal towards anti-SARS-CoV-2 biologics therapeutics. SARS-CoV neutralizing antibodies, m396, 80R, and CR-3022 were chosen as templates due to their diversified epitopes and confirmed neutralization potency against SARS. Structures of variable fragment (Fv) in complex with receptor binding domain (RBD) from SARS-CoV or SARS-CoV2 were subjected to our established in silico antibody engineering platform to improve their binding affinity to SARS-CoV2 and developability profiles. The selected top mutations were ensembled into a focused library for each antibody for further screening. In addition, we convert the selected binders with different epitopes into the trispecific format, aiming to increase potency and to prevent mutational escape. Lastly, to avoid antibody induced virus activation or enhancement, we applied NNAS and DQ mutations to the Fc region to eliminate effector functions and extend half-life.

bioengineering↗

bioRxiv2021

Vaccine genetics of IGHV1-2 VRC01-class broadly neutralizing antibody precursor naive human B cells

A successful HIV vaccine must overcome the hurdle of being able to activate naive precursor B cells encoding features within their germline B cell receptors (BCR) that allow recognition of broadly neutralizing epitopes. Knowledge of whether broadly neutralizing antibody (bnAb) precursor B cells are circulating at sufficient frequencies within individuals in communities heavily impacted by HIV may be important. Using a germline-targeting eOD-GT8 immunogen and high-throughput droplet-based single cell BCR sequencing, we demonstrate that large numbers of paired BCR sequences from multiple donors can be efficiently screened to elucidate precursor frequencies of rare, naive VRC01-class B cells. The results indicate that IGHV1-2 alleles incompatible with VRC01-class responses are relatively common in various human populations, and germline variation within IGHV1-2 associates with gene usage frequencies in the naive BCR repertoire.

immunology↗

bioRxiv2021

Analysis of the blood microbiome in a porcine model of fecal-induced peritonitis

BackgroundRecent studies have proposed the existence of a blood microbiome, even in the healthy host. However, we do not know how the blood microbiome changes when a bloodstream infection (BSI) occurs. Here, we analyzed the dynamics of the blood microbiome in a porcine model of polymicrobial bacteremia induced by fecal peritonitis. Serial blood samples were taken over 12 hours post-induction of fecal peritonitis, and BSI was validated by conventional blood culture and assessment of clinical symptoms. ResultsThe bacterial populations in the blood microbiome were retained throughout the experimental period. However, there were significant taxonomic differences between the profile in the fecal and blood microbiomes, reflecting tropism for the blood environment. We also confirmed that the microbiota we detected was not contaminated by low mass bacteria in the bloodstream. However, at the same time, we noted a slight increase in Bacteroidetes, which is a major component of the gut microbiome, as sepsis developed. Comparison of the functional pathways in the blood and fecal microbiomes revealed upregulation of pathways involved in environmental interactions, and downregulation of those related to cell proliferation, in the former. Based on the enriched biological pathways, we concluded that communication and stress management pathways are essential for the survival of the blood microbiome under harsh conditions. ConclusionThis study suggests that the microbiota can be stably retained in the bloodstream over time. Although further investigation in humans is required, we suggest that the blood microbiome may be another factor to be considered in the context of BSI and subsequent sepsis.

microbiology↗

bioRxiv2021

Seq-Scope: Submicrometer-resolution spatial transcriptomics for single cell and subcellular studies

Spatial barcoding technologies have the potential to reveal histological details of transcriptomic profiles; however, they are currently limited by their low resolution. Here we report Seq-Scope, a spatial barcoding technology with a resolution almost comparable to an optical microscope. Seq-Scope is based on a solid-phase amplification of randomly barcoded single-molecule oligonucleotides using an Illumina sequencing-by-synthesis platform. The resulting clusters annotated with spatial coordinates are processed to expose RNA-capture moiety. These RNA-capturing barcoded clusters define the pixels of Seq-Scope that are approximately 0.5-1 m apart from each other. From tissue sections, Seq-Scope visualizes spatial transcriptome heterogeneity at multiple histological scales, including tissue zonation according to the portal-central (liver), crypt-surface (colon) and inflammation-fibrosis (injured liver) axes, cellular components including single cell types and subtypes, and subcellular architectures of nucleus, cytoplasm and mitochondria. Seq-scope is quick, straightforward and easy-to-implement, and makes spatial single cell analysis accessible to a wide group of biomedical researchers.

bioengineering↗

bioRxiv2021

Control of topoisomerase II activity and chemotherapeutic inhibition by TCA cycle metabolites

Topoisomerase II (topo II) is essential for disentangling newly replicated chromosomes. DNA unlinking involves the physical passage of one DNA duplex through another and depends on the transient formation of double-strand DNA breaks, a step exploited by frontline chemotherapeutics to kill cancer cells. Although anti-topo II drugs are efficacious, they also elicit cytotoxic side effects in normal cells; insights into how topo II is regulated in different cellular contexts is essential to improve their targeted use. Using chemical fractionation and mass spectrometry, we have discovered that topo II is subject to metabolic control through the TCA cycle. We show that TCA metabolites stimulate topo II activity in vitro and that levels of TCA flux modulate cellular sensitivity to anti-topo II drugs in vivo. Our works reveals an unanticipated connection between the control of DNA topology and cellular metabolism, a finding with important ramifications for the clinical use of anti-topo II therapies.

biochemistry↗

bioRxiv2021

Discovery of μ,δ-Opioid receptor dual biased agonists that overcome the limitation of prior biased agonists

Morphine is widely used to manage pain in patients, although the risk of side effects is significant. The use of biased agonists to the G protein of -opioid receptors has been suggested as a potential solution, although Oliceridine and PZM21 have previously failed to demonstrate benefits in clinical studies. An amplification-induced confusion in the process of comparing G protein and beta-arrestin pathways may account for previous biased agonist mis-identification. Here, we have devised a strategy to discover biased agonists with intrinsic efficacy. We computationally simulated 430,000 molecular dockings to the -opioid receptor to construct a compound library. Hits were then verified by experiment. Using the verified compounds, we performed simulations to build a second library with a common scaffold, and selected compounds which show biased features to and {delta}-opioid receptors through a cell-based assay. Three compounds (ID110460001, ID110460002, and ID110460003) with a dual biased agonistic effect for and {delta}-opioid receptors were identified. These candidates are full agonists for the -opioid receptor, and they show specific binding modes. Based on our findings, we expect our novel compound to act as a biased agonist than conventional drugs such as Oliceridine.

pharmacology and toxicology↗

bioRxiv2020

Sestrins regulate age-induced deterioration of muscle stem cell homeostasis

The health and homeostasis of skeletal muscle is preserved by a population of tissue resident stem cells called satellite cells. Young healthy satellite cells maintain a state of quiescence, but aging or metabolic insults results in reduced capacity to prevent premature activation and stem cell exhaustion. As such, understanding genes and pathways that protect satellite cell maintenance of quiescence are needed. Sestrins are a class of stress-inducible proteins that act as antioxidants and inhibit the activation of the mammalian target of rapamycin complex 1 (mTORC1) signaling complex. Despite these pivotal roles, the role of Sestrins has not been explored in adult stem cells. Herein, we show that Sestrin1,2 loss results in hyperactivation of the mTORC1 complex, increased propensity to enter the cell cycle and shifts in metabolic flux. Aging of Sestrin1,2 knockout mice demonstrated a loss of MuSCs and reduced ability to regenerate. These findings demonstrate Sestrins function to help maintain MuSC metabolism that supports quiescence and against aging. HighlightsO_LISestrin deficiency alters mTORC1 signaling in muscle stem cells (MuSCs). C_LIO_LIIn young mice, Sestrins are dispensable for regenerative responses of MuSCs. C_LIO_LISestrin deficiency accelerates age-dependent loss and dysfunction of MuSCs. C_LI

cell biology↗