Biology subjects

Gong, L.

Publications and source records attributed to Gong, L..

48 records · Page 3Linked to original sources

bioRxiv2021

The PD-L1 and TLR7 dual-targeting nanobody-drug conjugate exerts potent antitumor efficacy by orchestrating innate and adaptive immune responses

A variety of tumors are insensitive to immune checkpoint blockade (ICB) therapy. We propose that ICB therapy alone is insufficient to fully reactivate antitumor T cells, while effective mobilization of antigen-presenting cells (APCs) to assist adaptive immune cell activation can lead to potent antitumor effects with broad responsiveness. The Toll-like receptor 7 (TLR7) agonist SZU-101 we developed can induce the innate immune response against tumors and increase the immunogenicity of tumors. Interestingly, SZU-101-induced upregulation of programmed death ligand 1 (PD-L1) expression in tumor tissues can further enhance the response rate of the PD-L1 antibody. In addition, PD-L1 nanobodies have better solid tumor penetration ability, and because of this ability, they can be used to precisely deliver SZU-101 to tumor tissues. Therefore, a PD-L1 and TLR7 dual-targeting nanobody-drug conjugate (NDC), a novel drug molecule, was developed. We found that TLR7 agonists and PD-L1 nanobodies act synergistically and that NDC treatment reshapes the tumor immune microenvironment, activates both innate and adaptive immune cells, and exerts antitumor effects in both "hot" and "cold" tumors primarily through CD8+ T cells and natural killer (NK) cells. Our data show that a PD-L1 and TLR7 dual-targeting NDC can exhibit potent antitumor efficacy by orchestrating innate and adaptive immune responses and shows good prospects for clinical development. One Sentence SummaryBased on results showing that TLR7 agonists and PD-L1 nanobodies exert synergistic antitumor effects, a PD-L1 and TLR7 dual-targeting nanobody-drug conjugate that we developed shows good prospects for clinical development because it can orchestrate innate and adaptive immune responses, reshape the tumor immune microenvironment, and exert potent antitumor effects against both "hot" and "cold" tumors.

immunology↗

bioRxiv2021

CoVac501, a self-adjuvanting peptide vaccine conjugated with TLR7 agonists, against SARS-CoV-2 induces protective immunity

Safe, economical and effective vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are needed to achieve adequate herd immunity and halt the pandemic. We have constructed a novel SARS-CoV-2 vaccine, CoVac501, which is a self-adjuvanting peptide vaccine conjugated with Toll-like receptor 7 (TLR7) agonists. The vaccine contains two immunodominant peptides screened from receptor-binding domain (RBD) and is fully chemically synthesized. And the vaccine has optimized nanoemulsion formulation, outstanding stability and safety. In non-human primates (NHPs), CoVac501 elicited high and persistent titers of RBD-specific and protective neutralizing antibodies (NAbs), which were also effective to RBD mutations. CoVac501 was found to elicit the increase of memory T cells, antigen-specific CD8+ T cell responses and Th1-biased CD4+ T cell immune responses in NHPs. More importantly, the sera from the immunized NHPs can prevent infection of live SARS-CoV-2 in vitro. One-Sentence SummaryA novel SARS-CoV-2 vaccine we developed, CoVac501, which is a fully chemically synthesized and self-adjuvanting peptides conjugated with TLR7 agonists, can induce high-efficient humoral and cellular immune responses against SARS-CoV-2.

immunology↗

bioRxiv2020

Ocular Dominance Plasticity: Measurement Reliability and Variability

AO_SCPLOWBSTRACTC_SCPLOWIn the last decade, studies have shown that short-term monocular deprivation strengthens the deprived eyes contribution to binocular vision. However, the magnitude of the change in eye dominance after monocular deprivation (i.e., the patching effect) has been found to be different between for different methods and within the same method. There are three possible explanations for the discrepancy. First, the mechanisms underlying the patching effect that are probed by different measurement tasks might exist at different neural sites. Second, test-retest variability in the measurement might have led to inconsistencies, even within the same method. Third, the patching effect itself in the same subject might fluctuate across separate days or experimental sessions. To explore these possibilities, we assessed the test-retest reliability of the three most commonly used tasks (binocular rivalry, binocular combination, and dichoptic masking) and the repeatability of the shift in eye dominance after short-term monocular deprivation for each of the task. Two variations for binocular phase combination were used, at one and many contrasts of the stimuli. Also, two variations of the dichoptic masking task was tested, in which the orientation of the mask grating was either horizontal or vertical. This makes five different measurement methods in all. We hope to resolve some of the inconsistencies reported in the literature concerning this form of visual plasticity. In this study, we also aim to recommend a measurement method that will allow us to better understand its physiological basis and the underpinning of visual disorders.

neuroscience↗

bioRxiv2020

Cascade Diversification Directs the Generation of Neuronal Diversity in Hypothalamus

The hypothalamus contains an astounding heterogeneity of neurons to achieve its role in regulating endocrine, autonomic and behavioral functions. Despite previous progress in deciphering the gene regulatory programs linked to hypothalamus development, its molecular developmental trajectory and origin of neuronal diversity remain largely unknown. Here we combine transcriptomic profiling of 43,261 cells derived from Rax+ hypothalamic neuroepithelium with lineage tracing to map a developmental landscape of mouse hypothalamus and delineate the developmental trajectory of radial glial cells (RGCs), intermediate progenitor cells (IPCs), nascent neurons and peptidergic neurons in the lineage hierarchy. We show that RGCs adopt a conserved strategy for multipotential differentiation but generate both Ascl1+ and Neurog2+ IPCs, which display regionally differential origins in telencephalon. As transit-amplifying cells, Ascl1+ IPCs differ from their telencephalic counterpart by displaying fate bifurcation to produce both glutamatergic and GABAergic neurons. After classifying the developing neurons into 29 subtypes coded by diverse transcription factors, neurotransmitters and neuropeptides, we identified their molecular determinants via regulon analysis and further found that postmitotic neurons at nascent state possess the potential to resolve into more diverse subtypes of peptidergic neurons. Together, our study offers a single-cell framework for hypothalamus development and reveals that multiple cell types along the order of lineage hierarchy contribute to the fate diversification of hypothalamic neurons in a stepwise fashion, suggesting that a cascade diversifying model can deconstruct the origin of neuronal diversity.

developmental biology↗

bioRxiv2020

SARS-CoV-2 invades host cells via a novel route: CD147-spike protein

Currently, COVID-19 caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been widely spread around the world; nevertheless, so far there exist no specific antiviral drugs for treatment of the disease, which poses great challenge to control and contain the virus. Here, we reported a research finding that SARS-CoV-2 invaded host cells via a novel route of CD147-spike protein (SP). SP bound to CD147, a receptor on the host cells, thereby mediating the viral invasion. Our further research confirmed this finding. First, in vitro antiviral tests indicated Meplazumab, an anti-CD147 humanized antibody, significantly inhibited the viruses from invading host cells, with an EC50 of 24.86 g/mL and IC50 of 15.16 g/mL. Second, we validated the interaction between CD147 and SP, with an affinity constant of 1.85x10-7M. Co-Immunoprecipitation and ELISA also confirmed the binding of the two proteins. Finally, the localization of CD147 and SP was observed in SARS-CoV-2 infected Vero E6 cells by immuno-electron microscope. Therefore, the discovery of the new route CD147-SP for SARS-CoV-2 invading host cells provides a critical target for development of specific antiviral drugs.

microbiology↗

bioRxiv2019

The complete mitochondrial genome of Calyptogena marissinica (Heterodonta: Veneroida: Vesicomyidae): insight into the deep-sea adaptive evolution of vesicomyids

The deep sea is one of the most extreme environments on earth, with low oxygen, high hydrostatic pressure and high levels of toxins. Species of the family Vesicomyidae are among the dominant chemosymbiotic bivalves found in this harsh habitat. Mitochondria play a vital role in oxygen usage and energy metabolism; thus, they may be under selection during the adaptive evolution of deep-sea vesicomyids. In this study, the mitochondrial genome (mitogenome) of the vesicomyid bivalve Calyptogena marissinica was sequenced with Illumina sequencing. The mitogenome of C. marissinica is 17,374 bp in length and contains 13 protein-coding genes, 2 ribosomal RNA genes (rrnS and rrnL) and 22 transfer RNA genes. All of these genes are encoded on the heavy strand. Some special elements, such as tandem repeat sequences, \"G(A)nT\" motifs and AT-rich sequences, were observed in the control region of the C. marissinica mitogenome, which is involved in the regulation of replication and transcription of the mitogenome and may be helpful in adjusting the mitochondrial energy metabolism of organisms to adapt to the deep-sea environment. The gene arrangement of protein-coding genes was identical to that of other sequenced vesicomyids. Phylogenetic analyses clustered C. marissinica with previously reported vesicomyid bivalves with high support values. Positive selection analysis revealed evidence of adaptive change in the mitogenome of Vesicomyidae. Ten potentially important adaptive residues were identified, which were located in cox1, cox3, cob, nad2, nad4 and nad5. Overall, this study sheds light on the mitogenomic adaptation of vesicomyid bivalves that inhabit the deep-sea environment.

molecular biology↗

bioRxiv2019

Multiple Cross Displacement Amplification Coupled with Gold Nanoparticles-Based Lateral Flow Biosensor for Detection of the Mobilized Colistin Resistance Gene mcr-1

Fast dissemination of the mobilized colistin resistance (mcr) gene mcr-1 in Enterobacteriaceae causes a huge threat to the treatment of severe infection. In the current report, a multiple cross displacement amplification (MCDA) coupled with the detection of amplified products by gold nanoparticles-based lateral flow biosensor (LFB) assay (MCDA-LFB) was established to identify the mcr-1 gene with simpleness, rapidity, specificity and sensitivity. The MCDA-LFB assay was performed at a isothermal temperature (63{degrees}C) for only 30 min during the amplification stage, and the reaction products were directly identified by using LFB which obtained the result with 2 min. The entire process of experiments, from templates extraction to result judging, was accomplished less than 60 min. For the analytical specificity of this method, all of the 16 mcr-1-producing strains were positive, and all of the non-mcr-1 isolates got the negative results. The sensitivity of mcr-1-MCDA-LFB assay was as little as 600 fg of plasmid DNA per reaction in pure culture, and approximately 4.5x103 CFU/mL (~4.5 CFU/reaction) in fecal samples spiked with 100 l of strains. Therefore, this technique established in the present study is suitable for the surveillance of mcr-1 gene in clinic and livestock industry.

molecular biology↗

bioRxiv2018

High resolution profile of body wide pathological changes induced by abnormal elastin metabolism in Loxl1 knockout mice

Abnormal ECM caused serious body wide diseases and elastin is one of the important ECM components. But its systemic function still has not yet been thoroughly illustrated due to limitations related to novel research technologies. To uncover the functions of elastin, a new method for body-wide organ transcriptome profiling, combined with single-cell mass cytometry of the blood, was developed. A body-wide organ transcriptomic (BOT) map was created by performing RNA-seq of 17 organs from both Loxl1 knockout (KO) and wide type (WT) mice. The BOT results showed a systematic up-regulation of genes related to immune response and proliferation process in multiple tissues of the KO mice; histological and immune staining also confirmed the hyperplasia and infiltration of local immune cells in the vagina, small intestine, and liver tissues of KO mice. Furthermore, using 32 markers, CYTOF mass cytometry analysis of the immune cell subpopulations from the peripheral blood revealed apparent systemic immune changes in the KO mice; data showed an activated NK cells and T cells with a higher expression of CD44 and CD38, and a suppressed B cells, macrophages and neutrophils with lower expressions of CD62L, CD44 and IL6. More interestingly, these findings also correlated well with the data obtained from cancer patient databases; tumor patients had higher mutation frequency of Loxl1, and the Loxl1-mutant tumor patients had up-regulated immune process, cell proliferation and decreased survival rate. Thus, this research provided a powerful strategy to screen body-wide organ functions of a particular gene; the findings also illustrated the important biological roles of elastin on multiple organ cells and systemic immunity. These strategy and discoveries are both of important value for the understanding of ECM biology and multi-organ cancer pathology.

cancer biology↗

bioRxiv2018

Cell atlas of human uterus

The human uterus is a highly dynamic tissue that undergoes repeated damage repair and regeneration during the menstrual cycle, which make it ideal model to study tissue regeneration and pathological process. Stem/progenitors were speculated to be involved in the regeneration of endometrial epithelial and pathogenesis of endometriosis. But the identity, microenvironment and regulatory mechanisms of the uterus epithelial stem/progenitors in vivo remain unclear. Here, we dissected the cell heterogeneities of the full-thickness human uterus epithelial cells (11 clusters), stroma cells (6 clusters), endothelial cells (5 clusters), smooth muscle cells (2 clusters), myofibroblasts (2 clusters) and immune cells (6 clusters) from 2735 single cell by single cell RNA-seq. Further analysis identified a unique ciliated epithelial cell cluster showing characteristics of stem/progenitors with properties of epithelial-mesenchymal transition (EMT) that mainly localized in the upper functionalis of the endometrium. Ordering the cell subpopulations along the pseudo-space revealed cell clusters possess cellular states of stress, inflammation and apoptosis in the upper functionalis cellular ecosystem of the endometrium. Connectivity map between the human uterus subpopulations revealed potential inflammatory (cytokines and chemokines) and developmental (WNT, FGF, VEGF) signals within the upper functionalis cellular ecosystem of the endometrium, especially from other epithelial clusters, regulating cell plasticity of the EMT-epithelial clusters. This study reconstructed the heterogeneities, space-specific distribution and connectivity map of human uterus atlas, which would provide insight in the regeneration of uterus endometria and reference for the pathogenesis of uterus.

cell biology↗

bioRxiv2018

Multiplex Chromatin Interaction Analysis with Single-Molecule Precision

We describe a microfluidics-based strategy for genome-wide analysis of multiplex chromatin interactions with single-molecule precision. In multiplex chromatin interaction analysis (multi-ChIA), individual chromatin complexes are partitioned into droplets that contain a gel bead with unique DNA barcode, in which tethered chromatin DNA fragments are barcoded and amplified for sequencing and mapping to demarcate chromatin contacts. Thus, multi-ChIA has the unprecedented ability to uncover multiplex chromatin interactions at single-molecule level, which has been impossible using previous methods that rely on analyzing pairwise contacts via proximity ligation. We demonstrate that multiplex chromatin interactions predominantly contribute to topologically associated domains, and clusters of gene promoters and enhancers provide a fundamental topological framework for co-transcriptional regulation.

genomics↗

bioRxiv2018

Local Delivery of Stromal Cell-Derived Factor-1α Improves the Pregnancy Rate of Injured Uterus through the Promotion of Endometrial and Vascular Regeneration

Severe infection and mechanical injury of the uterus may lead to infertility and miscarriage. Currently, there is a lack of effective treatment modality for functional repair of uterine injury. To address this clinical challenge, this study aimed to develop a chemotactic composite scaffold by incorporating recombinant human stromal cell-derived factor-1 (rhSDF-1) into a silk fibroin-bacterial cellulose (SF-BC) membrane carrier. A rat model of uterine injury was utilized for this study, which was composed of three groups: blank control, implantation with SF-BC only or SF-BC loaded with rhSDF-1. The tissue regeneration efficacy of the three groups were analyzed and compared. The results showed that SF-BC loaded with rhSDF-1 significantly enhanced endometrial regeneration and arteriogenesis of the injured rat uterus, which led to improved pregnancy outcomes, thus indicating much promise for functional uterine repair and regeneration.

bioengineering↗

bioRxiv2017

Nanopore Sequencing Reveals High-Resolution Structural Variation in the Cancer Genome

Acquired genomic structural variants (SVs) are major hallmarks of the cancer genome. Their complexity has been challenging to reconstruct from short-read sequencing data. Here, we exploit the long-read sequencing capability of the nanopore platform using our customized pipeline, Picky, to reveal SVs of diverse architecture in a breast cancer model. From modest sequencing coverage, we identified the full spectrum of SVs with superior specificity and sensitivity relative to short-read analyses and uncovered repetitive DNA as the major source of variation. Examination of the genome-wide breakpoints at nucleotide-resolution uncovered micro-insertions as the common structural features associated with SVs. Breakpoint density across the genome is associated with propensity for inter-chromosomal connectivity and transcriptional regulation. Furthermore, an over-representation of reciprocal translocations from chromosomal double-crossovers was observed through phased SVs. The comprehensive characterization of SVs using the robust long-read sequencing approach in cancer cohorts will facilitate strategies to monitor genome stability during tumor evolution and improve therapeutic intervention.

genomics↗