Biology subjects

Gao, Y.

Publications and source records attributed to Gao, Y..

At least 415 records · Page 23Linked to original sources

bioRxiv2022

Study on the mechanism of HE4 in hyperoxia-induced alveolar damage in rats

ObjectiveThis study investigated the mechanism of human epididymis protein 4 (HE4) in hyperoxia-induced alveolar damage in rats. MethodsThe pathological changes of SD rat lung tissue were detected by hematoxylin-eosin staining. Plasma protein levels were measured by enzyme-linked immunosorbent assay (ELISA). The expression of mRNA was detected by real-time RT-PCR. ResultsHyperoxia intervention within 7 days could induce acute lung injury in neonatal SD rats. Hyperoxia induction can increase HE4, MMP9 and TIMP1 in plasma and tissue of neonatal SD rats. By overexpressing and silencing HE4 gene in neonatal rat primary alveolar type II epithelial cells, we found that HE4 protein activates the phosphorylation of ERK and p65, activates the downstream MMP9 signaling pathway, inhibits MMP9 mRNA expression, inhibits protein activity, and reduces COLI degradation, increases collagen secretion, promoting matrix remodeling and fibrosis. ConclusionHE4 mediates the pathophysiological process of hyperoxia-induced lung injury in rats through ERK, MMP9 and TIMP1 signaling pathways. HE4 overexpression mediates lung basal remodeling and lung injury.

zoology↗

bioRxiv2022

Lifetime development changes in rats tracked by urinary proteome

The existing researches mainly focus on the embryonic stage and a short time after that. However, there was little research about the whole life of an individual from childhood to aging and death. For the first time, we used non-invasive urinary proteome technology to track the changes of several important development timepoints in a batch of rats, covering the 10 timepoints from childhood, adolescence, young, middle adulthood, and to old age death. As previous studies on puberty found, sexual or reproductive maturation, mature spermatozoa in seminiferous tubules(first seen), gonadal hormones, decline of estradiol(E), brain growth and central nervous system myelination, and our differential protein enrichment pathways also included reproductive system development, tube development, response to hormone, response to estradiol, brain development, neuron development. Like previous studies found in young adulthood, musculoskeletal maturity, peak bone mass, development of the immune system, and growth and physical development, and our differential protein enrichment pathway also included skeletal system development, bone regeneration, system development, immune system process, myeloid leukocyte differentiation, growth, and developmental growth. However, at all timepoints in the whole life, there were still many biological pathways of the differential urinary protein enrichment involving multiple organs, tissues, systems, etc., which had not been mentioned by existing studies. This study provided comprehensive and detailed changes in rats lifetime development through urinary proteome, supplementing the blank of development research. But also provided a new idea for monitoring the human health change condition and the possibly occurring aging diseases by using the urinary proteome. SummaryAs far as we know, this is the first time that the urinary proteome was used to track the changes of several important developmental timepoints in the lifetime of rats.

developmental biology↗

bioRxiv2022

A Computational Model of Learning Flexible Navigation in a Maze by Layout-Conforming Replay of Place Cells

Recent experimental observations have shown that the reactivation of hippocampal place cells (PC) during sleep or immobility depicts trajectories that can go around barriers and can flexibly adapt to a changing maze layout. Such layout-conforming replay sheds a light on how the activity of place cells supports the learning of flexible navigation in a dynamically changing maze. However, existing computational models of replay fall short of generating layout-conforming replay, restricting their usage to simple environments, like linear tracks or open fields. In this paper, we propose a computational model that generates layout-conforming replay and explains how such replay drives the learning of flexible navigation in a maze. First, we propose a Hebbian-like rule to learn the inter-PC synaptic strength during exploring a maze. Then we use a continuous attractor network (CAN) with feedback inhibition to model the interaction among place cells and hippocampal interneurons. The activity bump of place cells drifts along a path in the maze, which models layout-conforming replay. During replay in rest, the synaptic strengths from place cells to striatal medium spiny neurons (MSN) are learned by a novel dopamine-modulated three-factor rule to store place-reward associations. During goal-directed navigation, the CAN periodically generates replay trajectories from the animals location for path planning, and the trajectory leading to a maximal MSN activity is followed by the animal. We have implemented our model into a high-fidelity virtual rat in the MuJoCo physics simulator. Extensive experiments have demonstrated that its superior flexibility during navigation in a maze is due to a continuous re-learning of inter-PC and PC-MSN synaptic strength.

neuroscience↗

bioRxiv2022

Histopathological characteristics of different parts of surgical specimens of UPJ stenosis

ObjectiveTo observe the pathological changes of different anatomical sites in the specimens obtained from ureteropelvic junction obstruction (UPJO) caused by UPJ stenosis. Materials and MethodsA total of 34 cases of UPJO were performed. The lesion of the ureteropelvic junction was visualized as the center, the 1.5cm renal pelvis segment was taken along the upper edge of the lesion segment (as the control group). Along the lower edge of the ureteral stricture, 1cm of ureteral stricture tissue was taken downward. Different dyeing methods were used to observe the tissue arrangement of different parts, the ratio of muscle to fiber tissue and the distribution of interstitial cells of Cajal(ICC) . ResultsThe number of ICCs in the lesion segment was reduced or even absent, disordered arrangement of muscle tissue was seen, the fibrous tissue proliferated to varying degrees. The pathological changes were statistically different from those of normal segment and ureteral stricture segment. ConclusionThe decrease of ICCs cells and the degree of tissue fibrosis are closely related to the pathogenesis and disease progression of UPJO caused by UPJ stenosis.

developmental biology↗

bioRxiv2022

Kinetic and Structural Analysis of Ribonucleotide Extension by DNA Polymerase η

DNA polymerases catalyze DNA synthesis with high fidelity, which is essential for all life. Extensive kinetic and structural efforts have been executed in exploring mechanisms of DNA polymerases, surrounding their kinetic pathway, catalytic mechanisms, and factors that dictate polymerase fidelity. Recent time-resolved crystallography studies on DNA polymerase {eta} (Pol {eta}) and {beta} have revealed essential transient events during DNA synthesis reaction, such as mechanisms of primer deprotonation, separated roles of the three metal ions, and conformational changes that disfavor incorporation of the incorrect substrate. DNA-embedded ribonucleotides (rN) are the most common lesion on DNA and a major threat to genome integrity. While kinetics of rN incorporation has been explored and structural studies have revealed that DNA polymerases have a steric gate that destabilizes rNTP binding, mechanism of extension upon rN addition remains poorly characterized. Using steady-state kinetics, static and time-resolved X-ray crystallography with Pol {eta} as a model system, we showed that the extra hydroxyl group on the primer terminus does not reduce the catalytic efficiency of Pol {eta}. However, rN ended primers alter the dynamics of the polymerase active site as well as the catalysis and fidelity of DNA synthesis. During rN extension, Pol {eta} fidelity drops significantly across different sequence context. Systematic structural studies suggest that the rN at the primer end improved primer alignment and reduced barriers in C2-endo to C3-endo sugar conformation change. Our work provides important insights for rN extension and implicates a possible mechanism for rN removal.

biochemistry↗

bioRxiv2022

Changes of urinary proteome in an ApoE-/- mouse model of atherosclerosis

Cardiovascular disease is currently the leading cause of death worldwide. Atherosclerosis is an important pathological basis of cardiovascular disease, and its early diagnosis is of great significance. Urine is more conducive in the accumulation and response of changes in the physiological state of the body and is not regulated by homeostasis mechanisms, so it is a good source of biomarkers in the early stage of disease. In this study, ApoE-/- mice were fed with a high-fat diet for 5 months. Urine samples from the experimental group and control group, which were C57BL/6 mice fed a normal diet, were collected at seven time points. Proteomic analysis was used for internalcontrol and intergroup control. Internal control results showed a significant difference in the urinary proteome before and after a 1-week high-fat diet, and several differential proteins have been reported to be associated with atherosclerosis or for use as candidate biomarkers. The results of the intergroup control indicated that the biological process enriched by the GO analysis of the differential proteins corresponded to the progression of atherosclerosis. Differences in chemical modifications of urinary proteins have also been reported to be associated with the disease. This study demonstrates that urinary proteomics has the potential to monitor changes in the body sensitively and provides the possibility of identifying early biomarkers of atherosclerosis.

biochemistry↗

bioRxiv2022

Golgi-dependent Reactivation and Regeneration of Quiescent Neural Stem Cells

The ability of stem cells to switch between quiescent and proliferative states is crucial for maintaining tissue homeostasis and regeneration. In Drosophila, quiescent neural stem cells (qNSCs) extend a primary protrusion, which is removed prior to NSC reactivation. Here, we have unravelled that qNSC protrusions can be regenerated upon injury. This regeneration process relies on the Golgi apparatus which acts as the major acentrosomal microtubule-organizing centre in qNSCs. A Golgi-resident GTPase Arf1 and its guanine-nucleotide exchange factor Sec71 promote NSC reactivation and regeneration via the regulation of microtubule growth. Arf1 physically associates with its new effector Mini Spindles (Msps)/XMAP215, a microtubule polymerase. Finally, Arf1 functions upstream of Msps to target the cell-adhesion molecule E-cadherin to NSC-neuropil contact sites during NSC reactivation. Our findings have established Drosophila qNSCs as a new regeneration model and identified a novel Arf1/Sec71-Msps pathway in the regulation of microtubule growth and NSC reactivation.

cell biology↗

bioRxiv2022

Structural and Dynamic Basis of DNA Capture and Translocation by Mitochondrial Twinkle Helicase

Twinkle is the sole helicase responsible for mitochondrial DNA replication. Twinkle can selfload onto and unwind mitochondrial DNA. Nearly 60 mutations on Twinkle have been linked to human mitochondrial diseases. Using cryo-electron microscopy (cryo-EM) and High-speed atomic force microscope (HS-AFM), we obtained the atomic-resolution structure of a vertebrate Twinkle homolog with DNA and captured in real-time how Twinkle is self-loaded onto DNA. Our data highlight the essential role of the non-catalytic N-terminal domain of Twinkle. The N-terminal domain interacts with the helicase domain to stabilize Twinkle hexamers during translocation and the new domain-domain interface is a hotspot for disease-related mutations. The N-terminal domains can protrude approximately 5 nm to capture nearby DNA and initialize Twinkle loading onto DNA. Moreover, structural analysis and subunit doping experiments suggest that Twinkle hydrolyzes ATP stochastically, which explains the low efficiency of Twinkle DNA unwinding and implicates additional regulations of Twinkle during mitochondrial DNA replication.

biochemistry↗

bioRxiv2022

Further humoral immunity evasion of emerging SARS-CoV-2 BA.4 and BA.5 subvariants

Multiple BA.4 and BA.5 subvariants with R346 mutations on the spike glycoprotein have been identified in various countries, such as BA.4.6/BF.7 harboring R346T, BA.4.7 harboring R346S, and BA.5.9 harboring R346I. These subvariants, especially BA.4.6, exhibit substantial growth advantages compared to BA.4/BA.5. In this study, we showed that BA.4.6, BA.4.7, and BA.5.9 displayed higher humoral immunity evasion capability than BA.4/BA.5, causing 1.5 to 1.9-fold decrease in NT50 of the plasma from BA.1 and BA.2 breakthrough-infection convalescents compared to BA.4/BA.5. Importantly, plasma from BA.5 breakthrough-infection convalescents also exhibits significant neutralization activity decrease against BA.4.6, BA.4.7, and BA.5.9 than BA.4/BA.5, showing on average 2.4 to 2.6-fold decrease in NT50. For neutralizing antibody drugs, Bebtelovimab remains potent, while Evusheld is completely escaped by these subvariants. Together, our results rationalize the prevailing advantages of the R346 mutated BA.4/BA.5 subvariants and urge the close monitoring of these mutants, which could lead to the next wave of the pandemic.

immunology↗

bioRxiv2022

Urinary proteome changes during pregnancy in rats

Pregnancy involves a significant amount of physiological changes. A normal pregnancy is essential to ensure healthy maternal and fetal development. We sought to explore whether the urinary proteome could reflect the pregnancy process. Urine samples were collected from pregnant rats on gestational day 1, 4, 7, 11, 14, 16, 18, 20 (GD 1 d, GD 4 d, GD 7 d, GD 11 d, GD 14 d, GD 16 d, GD 18 d, GD 20 d), and control rats on days 0, 4, 7, 11, 14, 16, 18 and 20. The urinary proteome was profiled by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), and differential proteins were obtained by comparing the 0 d (GD 1 d) of the same group at each time point within the two groups. Through the analysis of the enriched pathways of differentially expressed proteins in the pregnant group, during the period from fertilization to implantation, many pathways related to embryo implantation and trophoblast differentiation were enriched on GD 1 d, GD 4 d and GD 7 d. In addition, the developmental process of the fetal rat heart such as heart looping and endocardial cushion formation, are consistent with the timing of previous studies; the developmental process of the lung and the development of the rat embryo alveoli before birth are consistent with the reported timing; and the developmental time of the rat embryo pancreas is also during the period of pancreatic cell proliferation and differentiation. These processes were enriched only in the pregnancy group and not in the control group. Furthermore, coagulation-associated pathways were found to be increasingly prominent before labor, which is consistent with the previously reported trend of increasing coagulation function during pregnancy. Our results indicated urinary proteome can reflect some embryonic developmental and maternal changes in rat pregnancy.

developmental biology↗

bioRxiv2022

Next-generation large-scale binary protein interaction network for Drosophila

Generating reference maps of the interactome networks underlying most cellular functions can greatly illuminate genetic studies by providing a protein-centric approach to finding new components of existing pathways, complexes, and processes. Here, we applied state-of-the-art experimental and bioinformatics methods to identify high-confidence binary protein-protein interactions (PPIs) for Drosophila melanogaster. We performed four all-by-all yeast two-hybrid (Y2H) screens of >10,000 Drosophila proteins, resulting in the FlyBi dataset of 8,723 PPIs among 2,939 proteins. As part of this effort, we tested subsets of our data and data from previous PPI datasets using an orthogonal assay, which allowed us to normalize data quality across datasets. Next, we integrated our FlyBi data with previous PPI data, resulting in an expanded, high-confidence binary Drosophila reference interaction network, DroRI, comprising 17,232 interactions among 6,511 proteins. These data are accessible through the Molecular Interaction Search Tool (MIST) and other databases. To assess the utility of the PPI resource, we used novel interactions from the FlyBi dataset to generate an autophagy interaction network that we validated in vivo using two different autophagy-related assays. We found that deformed wings (dwg) encodes a protein that is both a regulator and a target of autophagy. Altogether, the resources generated in this project provide a strong foundation for building high-confidence new hypotheses regarding protein networks and function.

cell biology↗

bioRxiv2022

Extensive plant use of exometabolites

Root exudation has been extensively studied due to its importance in soil carbon cycling and in supporting growth of soil microbes. However, the extent and dynamics of plant uptake of exogenous metabolites is poorly understood. To gain new insights into these processes we used 13C-tracing to characterize plant uptake of exometabolites across a panel of diverse plant species (Arabidopsis thaliana, Brachypodium distachyon, Lotus japonicus, Panicum virgatum, and Kalanchoe fedtschenkoi) grown in sterile hydroponic cultures. The uptake of exometabolites accounted for 23% of the overall B. distachyon carbon budget, and we identified 33 metabolites that were taken up by plants. Counterintuitively, many metabolites had higher uptake rates during the day vs. night. Thirteen of the metabolites from root exudates were found to promote root growth in A. thaliana, including hydroxybenzoate, threonate, N-acetyl-glucosamine, and uracil. Together these results indicate that the root uptake of organics can account for a significant portion of the plant carbon budget and that exogenous small molecules used by plants alter root growth with implications for plant nutrition, organic farming, soil nutrient cycling, and rhizosphere community dynamics.

plant biology↗

bioRxiv2022

Automated container-less cell processing method for single-cell proteomics

Single-cell genomics and transcriptomics studies enabled us to characterize cell heterogeneity in various tissues, which helped us to better understand the biological system and disease progression. Single-cell proteomics, which directly measures the protein expression level, has the potential to further enhance our knowledge by providing not only a more direct measurement but also crucial information cannot be captured by genomics or transcriptomics study, such as protein activation states and post-translation modification events. One of the main challenges of single-cell proteomics is the large sample loss during sample preparation, which is largely unavoidable using standard proteomics protocols. Protein and peptide loss to the container surface is a well-known phenomenon but often overlooked in larger-scale (>1 {micro}g) proteomics experiments. When it comes to single-cell proteomics with only picograms of protein samples, this loss becomes non-negligible and often dictates the outcomes of the experiment. More importantly, sample processing through multiple pipette tips and containers often introduces random errors, which undermine the ability to detect true heterogenous cellular events. To solve these problems and further improve the throughput and reproducibility of the single-cell proteomics experiments, we developed an automated container-less cell processing platform, utilizing acoustic levitation to process cell samples in the air. Our platform automatically performs cell lysis, protein reduction, alkylation, digestion, and peptide labeling in the air, without any sample transfer step or container. The digested and labeled peptides are then directly injected into the capillary LC-MS/MS system for analysis, eliminating manual steps and conserving most of the sample materials for proteomics analysis. Our initial test shows at least 30% improvement in peptide signals over conventional methods. This process can be performed in parallel to further improve sample processing throughput.

biochemistry↗

bioRxiv2022

Novel insights into L-serine exporters in Corynebacterium glutamicum from gene mining and functional analysis

Amino acid exporters play an important role in regulating amino acid production by Corynebacterium glutamicum, and over 90% of amino acid export is attributed to exporters in this species. ThrE was reported to be an O_SCPLOWLC_SCPLOW-serine exporter, and SerE was identified as an O_SCPLOWLC_SCPLOW-serine exporter in our previous study. However, when both ThrE and SerE were deleted, the O_SCPLOWLC_SCPLOW-serine titer was decreased by 60%, suggesting other O_SCPLOWLC_SCPLOW-serine exporters may exist. In the present study, NCgl0254 and NCgl0255 were identified as novel O_SCPLOWLC_SCPLOW-serine exporters through comparative transcriptomics and gene functional analyses. The contributions of the four exporters (ThrE, SerE, NCgl0254 and NCgl0255) in O_SCPLOWLC_SCPLOW-serine export were studied by gene deletion, gene overexpression, amino acid export assay and real-time quantitative PCR (RT-qPCR). The results showed that SerE is the major O_SCPLOWLC_SCPLOW-serine exporter in C. glutamicum. Fermentation and amino acid export assays of SSAAI, SSAAI-serE-thrE-ncgl0254-ncgl0255 and SSAAI{Delta}serE{Delta}thrE{Delta}ncgl0254{Delta}ncgl0255 indicated that the four O_SCPLOWLC_SCPLOW-serine exporters undertake most of the O_SCPLOWLC_SCPLOW-serine export, and their overexpression enhanced export of O_SCPLOWLC_SCPLOW-serine in SSAAI. When one O_SCPLOWLC_SCPLOW-serine exporter was deleted, the transcription level of the other three exporters was upregulated. However, the decrease in O_SCPLOWLC_SCPLOW-serine titer caused by deletion of one exporter was not fully compensated by upregulation of the other three exporters at the transcription level, indicating that O_SCPLOWLC_SCPLOW-serine production by C. glutamicum may be determined by cooperative efficiency of all four O_SCPLOWLC_SCPLOW-serine exporters, with each being interdependent. IMPORTANCEThis work identified the novel O_SCPLOWLC_SCPLOW-serine exporters NCgl0254 and NCgl0255, and revealed their roles in O_SCPLOWLC_SCPLOW-serine export alongside the O_SCPLOWLC_SCPLOW-serine exporters. All four O_SCPLOWLC_SCPLOW-serine exporters are interdependent and undertake most of the O_SCPLOWLC_SCPLOW-serine export, but SerE is the major O_SCPLOWLC_SCPLOW-serine exporter. The findings expand our knowledge of amino acid exporters in C. glutamicum, and the approach can be employed for exploring of bacterial exporters of unknown function.

bioengineering↗

bioRxiv2022

Osteocytes regulate organismal senescence of bone and bone marrow

The skeletal system contains a series of sophisticated cellular lineages arisen from the mesenchymal stem cells (MSC) and hematopoietic stem cells (HSC), that determine the homeostasis of bone and bone marrow. Here we reasoned that osteocyte may exert a function in regulation of these lineage cell specifications and tissue homeostasis. Using a mouse model of conditional deletion of osteocytes by the expression of diphtheria toxin subunit (DTA) in dentin matrix protein 1 (DMP-1) positive osteocytes, we demonstrated that partial ablation of DMP-1positive osteocytes caused severe sarcopenia, osteoporosis and degenerative kyphosis, leading to shorter lifespan in these animals. Osteocyte reduction altered mesenchymal lineage commitment resulting in impairment of osteogenesis and induction of osteoclastogensis. Single cell RNA sequencing further revealed that hematopoietic lineage was mobilized towards myeloid lineage differentiation with expanded myeloid progenitors, neutrophils and monocytes, while the lymphopoiesis was impaired with reduced B cells in the osteocyte ablation mice. The acquisition of a senescence-associated secretory phenotype (SASP) in both osteoprogenic and myeloid lineage cells was the underlying cause. Together, we showed that osteocytes play critical roles in regulating of lineage cell specifications in bone and bone marrow through mediation of organismal senescence.

cell biology↗

bioRxiv2022

Programming the lifestyles of engineered bacteria for cancer therapy

Bacteria can be genetically engineered to act as therapeutic delivery vehicles in the treatment of tumors, killing cancer cells or activating the immune system. This is known as Bacteria-Mediated Cancer Therapy (BMCT). Tumor invasion, colonization and tumor regression are major biological events, which are directly associated with antitumor effects and are uncontrollable due to the influence of tumor microenvironments during the BMCT process. Here, we developed a genetic circuit for dynamically programming bacterial lifestyles (planktonic, biofilm or lysis), to precisely manipulate the process of bacterial adhesion, colonization and drug release in BMCT process, via hierarchical modulation of the lighting power density (LPD) of near-infrared (NIR) light. The deep tissue penetration of NIR offers us a modality for spatiotemporal and noninvasive control of bacterial genetic circuits in vivo. By combining computational modeling with high throughput characterization device, we optimized the genetic circuits in engineered bacteria to program the process of bacterial lifestyle transitions by altering the illumination scheme of NIR. Our results showed that programming intratumoral bacterial lifestyle transitions allows precise control of multiple key steps throughout the BMCT process, and therapeutic efficacy can be greatly improved by controlling the localization and dosage of therapeutic agents via optimizing the illumination scheme.

synthetic biology↗

bioRxiv2022

Genetic score omics regression and multi-trait meta-analysis detect widespread cis-regulatory effects shaping bovine complex traits

To complete the genome-to-phenome map, transcriptome-wide association studies (TWAS) are performed to correlate genetically predicted gene expression with observed phenotypic measurements. However, the relatively small training population assayed with gene expression could limit the accuracy of TWAS. We propose Genetic Score Omics Regression (GSOR) correlating observed gene expression with genetically predicted phenotype, i.e., genetic score. The score, calculated using variants near genes with assayed expression, provides a powerful association test between cis-effects on gene expression and the trait. In simulated and real data, GSOR outperforms TWAS in detecting causal/informative genes. Applying GSOR to transcriptomes of 16 tissue (N[~]5000) and 37 traits in [~]120,000 cattle, multi-trait meta-analyses of omics-associations (MTAO) found that, on average, each significant gene expression and splicing mediates cis-genetic effects on 8[~]10 traits. Supported by Mendelian Randomisation, MTAO prioritised genes/splicing show increased evolutionary constraints. Many newly discovered genes/splicing regions underlie previously thought single-gene loci to influence multiple traits.

genomics↗

bioRxiv2022

Integrated single-cell sequencing analysis reveals peripheral immune landscape across the human lifespan

Systematic understanding of immune dynamics across the entire human lifespan at single-cell resolution is currently lacking. Here, we performed single-cell RNA sequencing (scRNA-seq) and single-cell T cell receptor (TCR)/B cell receptor (BCR) sequencing (scTCR/BCR-seq) on over 380,000 peripheral blood mononuclear cells collected from 45 healthy participants aged 0 to over 90 years. We revealed that the functions of T cell subsets were most susceptible to senescence among all PBMCs, featured by increased NF-{kappa}B signaling and IFN-{gamma} responses pathways, while reduced telomere maintenance and energy metabolism. We subsequently explored the rewiring of cell-cell interactions among different immune cells across the lifespan and revealed the major alteration of immune checkpoints in T cells within the cellular interaction networks. By combined analysis of scRNA-seq and scTCR-seq, we revealed that 1) GNLY+ CD8 Effector T cells exhibited a high clonal expansion with distinct functional signatures in children and the elderly; 2) Naive CD4+ T and naive CD8+ T cells displayed different aging patterns in both transcriptomes and immune repertoires; and 3) CD8+ MAIT cells showed a higher cell abundance and clonal diversity in adolescents. Furthermore, we identified a unique cytotoxic B cell subset enriched in children by scRNA-seq and scBCR-seq analysis and experimental validations. In summary, our work provided valuable insights and rich resources for understanding the development and aging of the human immune system across the lifespan.

immunology↗