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Chen, L.

Publications and source records attributed to Chen, L..

At least 379 records · Page 21Linked to original sources

Mechanisms of urate transport and uricosuric drugs inhibition in human URAT1

High urate levels in circulation lead to the accumulation of urate crystals in joints and ultimately inflammation and gout1. The reabsorption process of urate in the kidney by the urate transporter URAT1 plays a pivotal role in controlling serum urate levels2. Pharmacological inhibition of URAT1 by uricosuric drugs is a valid strategy for gout management3. Despite the clinical significance of URAT1, its structure and mechanism remain elusive. Here, we report the structures of human URAT1 (hURAT1) in complex with substrate urate or inhibitors benzbromarone and verinurad at resolution ranges from 3.0 to 3.3 [A]. Urate-bound hURAT1 adopts the outward-facing conformation. Urate is wrapped in the center of hURAT1 by five phenylalanines and coordinated by two positively charged residues on each side. Uricosuric compounds benzbromarone and verinurad occupy the urate-binding site of hURAT1 in the inward-facing conformation. Structural comparison between different conformations of hURAT1 reveals the rocker-switch-like mechanism for urate transport. Benzbromarone and verinurad exert their inhibitory effect by blocking not only the binding of urate but also the structural isomerization of hURAT1.

biochemistry↗

Deep Generative Optimization of mRNA Codon Sequences for Enhanced Protein Production and Therapeutic Efficacy

Messenger RNA (mRNA) therapeutics show immense promise, but their efficacy is limited by suboptimal protein expression. Here, we present RiboDecode, a deep learning framework that generates mRNA codon sequences for enhanced mRNA translation. RiboDecode introduces several advances, including direct learning from large-scale ribosome profiling data and generative exploration of a large sequence space. In silico analysis demonstrates RiboDecode s robust predictive accuracy for unseen genes and cellular environments. In vitro experiments showed substantial improvements in protein expression, significantly outperforming past methods. In addition, RiboDecode enables mRNA design with consideration of cellular context and demonstrates robust performance across different mRNA formats, including m1{Psi}-modified and circular mRNAs, an important feature for mRNA therapeutics. In vivo mouse studies showed that optimized influenza hemagglutinin mRNAs induce ten times stronger neutralizing antibody responses against influenza virus compared to the unoptimized sequence. In an optic nerve crush model, optimized nerve growth factor mRNAs achieve equivalent neuroprotection of retinal ganglion cells at one-fifth the dose of the unoptimized sequence. Collectively, RiboDecode represents a paradigm shift from rule-based to a data-driven, context-aware approach for mRNA therapeutic applications, enabling the development of more potent and dose-efficient treatments.

bioinformatics↗

Deciphering the Cell Specific Transcript Heterogeneity and Alternative Splicing during the Early Embryonic Development of Zebrafish

Cell fate determination during early embryonic development is a complex process modulated by gene expression. The intricate interplay of transcriptional and post-transcriptional regulation is integral to the developmental trajectory of embryogenesis, yet how RNA processing may contribute to early development programming is largely elusive. Leveraging recent technological advances in single-molecule nanopore sequencing, we developed a single-cell long-read transcriptome sequencing technology, allowing a clear view of transcript diversity during zebrafish embryogenesis during pre- and post-zygotic genome activation (ZGA). A closer examination of the dynamic transcript usage and potential alternative splicing revealed that abundant stage-specific transcripts with differential coding potentials are involved in distinct biological functions. Specifically, we identified two cell populations at the onset of ZGA based on isoform diversity instead of gene profiling, which followed divergent developmental trajectories toward the ectoderm and the presumptive ectoderm. These two populations of cells were characterized by divergent splicing regulations linked to differential RNA-binding proteins, including SNRPA and SFPQ. Altogether, using the single-cell long-read transcriptome sequencing strategy, we work has revealed the cell-specific transcriptome dynamics contributing to the cell fate determination during embryogenesis.

developmental biology↗

Genetic ancestry in Puerto Rican Afro-descendants illustrates diverse histories of African diasporic populations

ObjectivesGenetic studies of contemporary Puerto Ricans reflect a demographic history characterized by admixture between Indigenous American, African, and European peoples. While previous studies provide genetic perspectives on the general Puerto Rican population, less is known about the islands sub-populations, specifically Afro-Puerto Ricans. Materials and MethodsIn this study, the genetic ancestry of Afro-Puerto Ricans is characterized and compared to other Caribbean populations. Thirty DNA samples collected among self-identified Puerto Ricans of African descent in Loiza (n=2), Pinones (n=13), San Juan (n=2), Mayaguez (n=9), and Ponce (n=4), were genotyped at 750,000 loci on the National Geographic Genochip. We then applied unsupervised clustering and dimensionality-reduction methods to detect continental and subcontinental African and European genetic ancestry patterns. ResultsAdmixture analyses reveal that on average, the largest genetic ancestry component for Afro-Puerto Ricans is African in origin, followed by European and Indigenous American genetic ancestry components. African biogeographic origins of Afro-Puerto Ricans align most closely with contemporary peoples of Lower Guinea and the Bight of Biafra, while the European genetic ancestry component is most similar to contemporary Iberian, Italian, and Basque populations. These findings contrast with the biogeographic origins of comparative Barbadian and Puerto Rican populations. DiscussionOur results suggest that while there are similarities in general patterns of genetic ancestry among African descendants in the Caribbean, there is previously unrecognized regional heterogeneity, including among Puerto Rican sub-populations. These results are also consistent with available historical sources, while providing depth absent from the documentary record, particularly with regard to African ancestry.

genomics↗

Climate History and Metabolic Trade-offs shape the Bacterial Response to Drought

Soil drying challenges microbial viability and survival, with bacteria employing various mechanisms to respond to shifts in osmolarity, including dormancy or metabolic upregulation of osmoprotectants. However, the extent to which these responses are shaped by an organisms phylogeny or the climate history of a given environment is poorly understood. This study examines the responses of phylogenetically similar bacteria from semi-arid and humid tropical forest soils to osmotic and matric stress using synchrotron radiation-based Fourier Transform Infrared spectromicroscopy. This non-destructive approach depicts the biochemical phenotype for whole cells under control and stress conditions. We observed that, under osmotic stress, bacteria upregulated cell-signaling pathways, rapidly turned over lipid-storage compounds, and increased osmolyte production. In contrast, matric stress induced a more muted response, typically elevating the production of carbohydrate stress compounds, such as glycine betaine and trehalose. While phylogenetically similar bacteria showed comparable biochemistry under control conditions, climate history played an important role in regulating responses to stress, whereby a stronger metabolic response was observed from semi-arid relative to tropical forest isolates. We conclude that bacterial stress response to drought can be more diverse than previously observed, and regulated by both phylogeny and climate history.

microbiology↗

Vascular network-inspired diffusible scaffolds for engineering functional neural organoids

Organoids, three-dimensional in vitro organ-like tissue cultures derived from stem cells, show promising potential for developmental biology, drug discovery, and regenerative medicine. However, the function and phenotype of current organoids, especially neural organoids, are still limited by insufficient diffusion of oxygen, nutrients, metabolites, signaling molecules, and drugs. Herein, we present Vascular network-Inspired Diffusible (VID) scaffolds to fully recapture the benefits of physiological diffusion physics for generating functional organoids and phenotyping their drug response. In a proof-of-concept application, the VID scaffolds, 3D-printed meshed tubular channel networks, support the successful generation of engineered human midbrain organoids almost without necrosis and hypoxia in commonly used well-plates. Compared to conventional organoids, these engineered organoids develop with more physiologically relevant features and functions including midbrain-specific identity, oxygen metabolism, neuronal maturation, and network activity. Moreover, these engineered organoids also better recapitulate pharmacological responses, such as neural activity changes to fentanyl exposure, compared to conventional organoids with significant diffusion limits. Combining these unique scaffolds and engineered organoids may provide insights for organoid development and therapeutic innovation.

bioengineering↗

Genome-wide A to G and C to T Mutations Induced by Functional TadA Variants in Escherichia coli

The fusion expression of DNA replication-related proteins with nucleotide deaminase enzymes promotes random mutations in bacterial genomes, thereby increasing genetic diversity among population. Most previous studies have focused on cytosine deaminase, which produces only C[->]T mutations, significantly limiting the variety of mutation types. In this study, we developed a fusion expression system by combining DnaG (RNA primase) with adenine deaminase TadA-8e (DnaG-TadA) in Escherichia coli, which is capable of rapidly introducing A[->]G mutations into the E. coli genome, resulting in a 664-fold increase in terms of mutation rate. Additionally, we engineered a dual-functional TadA variant, TadAD, and then fused it with DnaG. This construct introduced both C[->]T and A[->]G mutations into the E. coli genome, with the mutation rate further increased by 370-fold upon co-expression with an uracil glycosylase inhibitor (DnaG-TadAD-UGI). We applied DnaG-TadA and DnaG-TadAD-UGI systems to the adaptive laboratory evolution for Cd2+ and kanamycin resistance, achieving an 8.0 mM Cd2+ and 200 g/mL kanamycin tolerance within just 17 days and 132 hours, respectively. Compared to conventional evolution methods, the final tolerance levels were increased by 320% and 266%, respectively. Our work offers a novel strategy for random mutagenesis in E. coli and potentially other prokaryotic species. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=98 SRC="FIGDIR/small/610230v1_ufig1.gif" ALT="Figure 1"> View larger version (22K): org.highwire.dtl.DTLVardef@176e445org.highwire.dtl.DTLVardef@848b7corg.highwire.dtl.DTLVardef@1e190b9org.highwire.dtl.DTLVardef@1e47b44_HPS_FORMAT_FIGEXP M_FIG C_FIG For TOC only

synthetic biology↗

Epigenetic control of commensal induced Th2 Responses and Intestinal immunopathology

Understanding the initiation of T-helper (Th)-2 immunity is crucial for addressing allergic diseases that have been linked to the commensal microbiota. However, Th2 responses are notably absent from known host-microbiota intestinal immune circuits. Notably, the commensal protist Tritrichomonas induces a transient innate ILC2 circuit rather than a chronic Th2 circuit. Canonical Th2 responses rely on the induction of IL-4 production by innate cells. This study shows that the absence of Tet2, a DNA demethylase, reprograms naive T cells to autonomously produce IL-4 upon T cell receptor stimulation, bypassing the need for IL-4 from innate cells for Th2 differentiation. Loss of this checkpoint induces chronic Th2 responses to Tritrichomonas, associated with IL-25-dependent barrier dysfunction and increased susceptibility to allergic pathology in response to dietary antigens. Sentence SummaryRegulation of cell autonomous IL-4 in T cells is critical to prevent dysregulated Th2 immunity to commensals and predisposition to allergy.

immunology↗

Enhanced Salt Tolerance in Synechocystis sp. PCC 6803 Through Adaptive Evolution: Mechanisms and Applications for Environmental Bioremediation

Salt stress is common in natural environments, where elevated salt levels in brackish water and saline soil can hinder the growth of organisms, thereby exacerbating environmental challenges. Developing salt-tolerant organisms not only uncovers novel mechanisms of salt tolerance but also lays the groundwork for managing and utilizing saline environments. Cyanobacteria, which are widely distributed in hydrosphere and soil, serve as ideal models for studying salt stress. In this study, the model cyanobacterium Synechocystis sp. PCC 6803 was selected, whose salt (NaCl) tolerance improved from 4.0% to 6.5% (m/v) through adaptive laboratory evolution. Genome re-sequencing and mutant analysis identified six key genes associated with salt tolerance. Notably, the deletion of slr1670, which encodes glycerol glucoside hydrolase, improved the strains salt tolerance. In addition, slr1753 encodes a membrane protein that may enhance salt tolerance by facilitating ion transport to the extracellular space. Further analysis revealed that overexpression of slr1753 significantly accumulates Na+ on the cell surface, enabling effective seawater treatment using the engineered strain, resulting in a 6.35% reduction of Na+ in the seawater. Moreover, the adapted bacteria can be used for the remediation of saline soil samples, leading to a 184.2% and 43.8% increase in the germination rate and average height of Brassica rapa chinensis, respectively, along with a 25.3% rise in total organic carbon content and reductions in both total salt content by 1.82% and pH by 1.91% in soil. This study provides novel insights into salt tolerance mechanisms and the bioremediation of high-salinity environments. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=105 SRC="FIGDIR/small/610226v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@cde16aorg.highwire.dtl.DTLVardef@8a27ccorg.highwire.dtl.DTLVardef@3af9bforg.highwire.dtl.DTLVardef@1e29cfb_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

LncRNA-536 and RNA Binding Protein RBM25 Interactions in Pulmonary Arterial Hypertension

OBJECTIVEHyperproliferation of pulmonary artery smooth muscle cells (PASMCs) is one of the essential features of the maladaptive inward remodeling of the pulmonary arteries in pulmonary arterial hypertension (PAH). In this study, we define the mechanistic association between long-noncoding RNA: ENST00000495536 (Lnc-536) and anti-proliferative HOXB13 in mediating smooth muscle hyperplasia. METHODSAntisense oligonucleotide-based GapmeRs or plasmid overexpressing lnc-536 were used to evaluate the role of lnc-536 in mediating hyperproliferation of PDGF-treated or idiopathic PAH (IPAH) PASMCs. Further, we pulled down lnc536 to identify the proteins directly interacting with lnc536. The in-vivo role of lnc-536 was determined in Sugen-hypoxia and HIV-transgenic pulmonary hypertensive rats. RESULTSIncreased levels of lnc-536 in PDGF-treated or IPAH PASMCs promote hyperproliferative phenotype by downregulating the HOXB13 expression. Knockdown of lnc-536 in-vivo prevented increased RVSP, Fulton Index, and pulmonary vascular remodeling in Sugen-Hypoxia rats. The lncRNA-536 pull-down assay demonstrated the interactions of RNA binding protein: RBM25 with SFPQ, a transcriptional regulator that has a binding motif on HOXB13 exon Further, The RNA-IP experiment using the SFPQ antibody showed direct interaction of RBM25 with SFPQ and knockdown of RBM25 resulted in increased interactions of SFPQ and HOXB13 mRNA while attenuating PASMC proliferation. Finally, we examined the role of lnc-536 and HOXB13 axis in the PASMCs exposed to the dual hit of HIV and a stimulant: cocaine as well. CONCLUSIONlnc-536 acts as a decoy for RBM25, which in turn sequesters SFPQ, leading to the decrease in HOXB13 expression and hyperproliferation of smooth muscle cells associated with PAH development.

cell biology↗

δ-α cell-to-cell interactions modulate pancreatic islet Ca2+ oscillation modes

Glucose-induced pancreatic islet hormone release is tightly coupled with oscillations in cytoplasmic free Ca2+ concentration of islet cells, which is regulated by a complex interplay between intercellular and intracellular signaling. {delta} cells, which entangle with cells located at the islet periphery, are known to be important paracrine regulators. However, the role of {delta} cells in regulating Ca2+ oscillation pattern remains unclear. Here we show that {delta}- cell-to-cell interactions are the source of variability in glucose-induced Ca2+ oscillation pattern. Somatostatin secreted from {delta} cells prolonged the islets oscillation period in an cell mass-dependent manner. Pharmacological and optogenetic perturbations of {delta}- interactions led islets to switch between fast and slow Ca2+ oscillations. Continuous adjustment of {delta}- coupling strength caused the fast oscillating islets to transition to mixed and slow oscillations. We developed a mathematical model, demonstrating that the fast-mixed-slow oscillation transition is a Hopf bifurcation. Our findings provide a comprehensive understanding of how {delta} cells modulate islet Ca2+ dynamics and reveal the intrinsic heterogeneity of islets due to the structural composition of different cell types. HighlightsO_LISomatostatin slows down islet Ca2+ oscillations in an cell mass-dependent manner. C_LIO_LIPharmacological and optogenetic perturbations of {delta}- interaction cause islet Ca2+ oscillation mode switching. C_LIO_LIContinuous tuning of {delta}- interaction strength induces fast-mixed-slow oscillation transition successively. C_LIO_LIMathematical modeling shows the fast-mixed-slow oscillation transition as a Hopf bifurcation. C_LI

systems biology↗

Endoplasmic reticulum patterns insect cuticle nanostructure

Insect cuticles with nano-level structures exhibit functional surface properties such as structural color and superhydrophobicity. Despite the enormous influence the cuticle has had on biomimetic industrial applications, molecular and cellular mechanisms of cuticular extracellular matrix (ECM) assembly into nanoscale structures remain poorly understood in insects and other taxa. Ghiradella (1989) described how a crystallin-like lattice of endoplasmic reticulum (ER) prefigures the patterning of the porous cuticle of the butterfly wing scale with structural color1. Building on that insight, we show that the nanopore structure of the olfactory (olf) organs, which serve as molecular filters in Drosophila, is built through a novel process in which ER material is trafficked to the plasma membrane mediated by the autophagy pathway. The process is controlled by the insect-specific protein Gore-tex/Osiris23 (Gox)2, which is localized to the tubular ER of olf hair cells. Gox recruits Ref(2)P, the fly counterpart of mammalian p62/SQSTM13, to initiate ER scission. The excised ER fragments are processed by autophagy to gain access to the plasma membrane and trigger membrane invagination, which plays a role in remodeling the cuticular envelope layer to the nanopore formation. This repurposing of the ER phagy for machinery to support the fabrication of nanoscale ECM by the Gox protein sheds light on the nanopatterning of insect cuticles and their genetic control.

developmental biology↗

Conserved RNA-binding protein interactions mediate syntologous lncRNA functions

Syntologous long noncoding RNAs (lncRNAs) are loci with conserved genomic positions that often show little or no sequence similarity. Despite diverging primary sequences, lncRNA syntologs from distant species can carry out similar functions. However, determinants underlying conserved functions of syntologous lncRNA transcripts with no sequence similarity remain unknown. Using CASC15 and melanoma formation as a paradigm for fast evolving lncRNAs and their functions, we found that human and zebrafish CASC15 syntologs with no detectable sequence similarity retained their function across 450 million years of evolution. Similar to the casc15-deficient zebrafish, CASC15-mutant human melanoma cells show increased cell migration. Expression of human CASC15 in zebrafish rescues loss of casc15 function by attenuating melanoma formation. This conserved function is supported by a set of RNA-binding proteins, interacting with both zebrafish and human CASC15 transcripts. Together, our findings demonstrate that conserved RNA-protein interactions can define functions of rapidly evolving lncRNA transcripts.

molecular biology↗

A single-molecule nanopore sequencing platform

Nanopore sequencing, a third-generation sequencing technology, has revolutionized the gene sequencing industry with its advantages of long reads, fast speed, real-time sequencing and analysis, and potential in detecting base modifications. This technology allows researchers to sequence longer DNA fragments in a single read, providing more comprehensive genomic information compared to previous methods. Nanopore sequencing operates on electrical signals generated by a nanopore embedded in a membrane separating two electrolyte-filled chambers. When single-stranded DNA (ssDNA) passes through the nanopore, it creates variations in the current that correspond to different DNA bases. By analyzing these current fluctuations with machine learning algorithms, the DNA sequence can be determined. In this study, we introduced several improvements to nanopore sequencing, including nanopore local chemistry sequencing, novel motor and pore proteins, chip design, and basecalling algorithms. Our new nanopore sequencing platform, CycloneSEQ, demonstrated long-duration sequencing (107 hours) on a single chip with high yield (>50 Gb). In human genomic DNA sequencing, CycloneSEQ was able to produce long reads with N50 33.6 kb and modal identity 97.0%. Preliminary findings on human whole-genome de novo assembly, variant calling, metagenomics sequencing, and single-cell RNA sequencing have further highlighted CycloneSEQs potential across different areas of genomics.

genomics↗

MiniXL: An open-source, large field-of-view epifluorescence miniature microscope for mice capable of single-cell resolution and multi-brain region imaging

Capturing the intricate dynamics of neural activity in freely behaving animals is essential for understanding the neural mechanisms underpinning specific behaviors. Miniaturized microscopy enables investigators to track population activity at cellular level, but the field of view (FOV) of these microscopes have been limited and does not allow multiple-brain region imaging. To fill this technological gap, we have developed the eXtra Large field-of-view Miniscope (MiniXL), a 3.5g lightweight miniaturized microscope with an FOV measuring 3.5 mm in diameter and an electrically adjustable working distance of 1.9 mm {+/-} 200 m. We demonstrated the capability of MiniXL recording the activity of large neuronal population in both subcortical area (hippocampal dorsal CA1) and deep brain regions (medial prefrontal cortex, mPFC and nucleus accumbens, NAc). The large FOV allows simultaneous imaging of multiple brain regions such as bilateral mPFCs or mPFC and NAc during complex social behavior and tracking cells across multiple sessions. As with all microscopes in the UCLA Miniscope ecosystem, the MiniXL is fully open-source and will be shared with the neuroscience community to lower the barriers for adoption of this technology.

neuroscience↗

Steering cell-state and phenotype transitions by causal disentanglement learning

Understanding and manipulating cell-state and phenotype transitions is essential for advancing biological research and therapeutic treatment. We introduce CauFinder, an advanced framework designed to accurately identify causal regulators of these transitions and further precisely steer such transitions by integrating causal disentanglement modelling with network control based solely on observed data. By leveraging do-calculus and optimizing information flow metrics, CauFinder can distinguish causal factors from spurious ones, ensuring precise control over desired state transitions. One significant advantage of CauFinder is its ability to identify those variables causally affecting the cell-state/phenotype transitions among all observed variables, both theoretically and computationally, leading to the identification of their master regulators when combined with network control. Consequently, by employing a counterfactual algorithm, CauFinder is able effectively to facilitate desirable state transitions or steer these transitional trajectories/paths by modulating these causal drivers. Beyond its theoretical advantages, CauFinder outperforms existing approaches computationally in both simulated and real-world settings. CauFinder is able to not only reveal natural biological transition processes such as (a) cell differentiation, (b) lung adenocarcinoma (LUAD) to lung squamous cell carcinoma (LUSC) transdifferentiation and (c) drug-sensitive to drug-resistant transitions but also identify the causal regulators of their reverse transition processes, such as (A) cell dedifferentiation, (B) LUSC to LUAD transdifferentiation and (C) drug-resistant to drug-sensitive transitions. These findings highlight its superior ability to causally uncover essential regulatory mechanisms and accurately steer cell-state/phenotype transitions, thus providing novel therapeutic strategies.

bioinformatics↗

Single-cell analysis identifies distinct CD4+ T cells associated with the pathobiology of pediatric obesity-related asthma

Pediatric obesity-related asthma is characterized by non-atopic T helper 1 (Th1) inflammation and steroid resistance. CDC42 upregulation in CD4+T cells underliesTh1 inflammation but the CD4+T cell subtype(s) with CDC42 upregulation and their contribution to steroid resistance are not known. Compared to healthy-weight asthma, obesity-alone and healthy-weight controls, single-cell transcriptomics of obese asthma CD4+T cells revealed CDC42 upregulation in 3 clusters comprised of naive and central memory T cells, which differed from the cluster enriched for Th1 responses that was comprised of effector T cells. NR3C1, coding for glucocorticoid receptor, was downregulated, while genes coding for NLRP3 inflammasome were upregulated, in clusters with CDC42 upregulation and Th1 responses. Conserved genes in these clusters correlated with pulmonary function deficits in obese asthma. These findings suggest that several distinct CD4+T cell subtypes are programmed in obese asthma for CDC42 upregulation, Th1 inflammation, and steroid resistance, and together contribute to obese asthma phenotype. SummaryCD4+T cells from obese children with asthma are distinctly programmed for non-allergic immune responses, steroid resistance and inflammasome activation, that underlie the obese asthma phenotype.

immunology↗

Synaptic synergy of T cell receptor and interleukin 2 receptor in CD8+ T cells

Interleukin 2 (IL2) promotes T cell proliferation and differentiation, making it a central target in immunotherapies. T cells fine-tune their sensitivity to and consumption of IL2 by regulating surface expression and composition of the IL2 receptor. Following antigen recognition, IL2 receptor signaling is shared through polarized interactions in T cell aggregates. However, how IL2 function is integrated during earlier antigen-dependent T cell synapses is unknown. Here, we demonstrate a synergistic effect between the T cell receptor (TCR) and IL2 receptor signaling at the immunological synapse of CD8+ T cells with supported lipid bilayers. TCR and IL2 signaling overlapped in space and time, potentiating each other when simultaneously triggered. Immuno-STATs, a safe and effective new class of immunotherapeutics, which fuse IL2 and peptide-major histocompatibility complex (pMHC) in a single molecule to expand antigen-specific CD8+ T cells, enhanced both TCR and IL2 signaling and promoted antigen specific T-T immunological synapses.

immunology↗