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1.
Cell ; 178(3): 567-584.e19, 2019 07 25.
Article in English | MEDLINE | ID: mdl-31348886

ABSTRACT

The vaccine-mediated elicitation of antibodies (Abs) capable of neutralizing diverse HIV-1 strains has been a long-standing goal. To understand how broadly neutralizing antibodies (bNAbs) can be elicited, we identified, characterized, and tracked five neutralizing Ab lineages targeting the HIV-1-fusion peptide (FP) in vaccinated macaques over time. Genetic and structural analyses revealed two of these lineages to belong to a reproducible class capable of neutralizing up to 59% of 208 diverse viral strains. B cell analysis indicated each of the five lineages to have been initiated and expanded by FP-carrier priming, with envelope (Env)-trimer boosts inducing cross-reactive neutralization. These Abs had binding-energy hotspots focused on FP, whereas several FP-directed Abs induced by immunization with Env trimer-only were less FP-focused and less broadly neutralizing. Priming with a conserved subregion, such as FP, can thus induce Abs with binding-energy hotspots coincident with the target subregion and capable of broad neutralization.


Subject(s)
AIDS Vaccines/immunology , Antibodies, Neutralizing/immunology , HIV Antibodies/immunology , Peptides/immunology , Amino Acid Sequence , Animals , Antibodies, Neutralizing/chemistry , Antibodies, Neutralizing/classification , B-Lymphocytes/cytology , B-Lymphocytes/metabolism , Crystallography, X-Ray , Female , HEK293 Cells , HIV Antibodies/chemistry , HIV Antibodies/classification , HIV-1/metabolism , Humans , Macaca mulatta , Male , Peptides/chemistry , Protein Structure, Tertiary , env Gene Products, Human Immunodeficiency Virus/chemistry , env Gene Products, Human Immunodeficiency Virus/immunology , env Gene Products, Human Immunodeficiency Virus/metabolism
2.
Cell ; 165(4): 813-26, 2016 May 05.
Article in English | MEDLINE | ID: mdl-27114034

ABSTRACT

The HIV-1-envelope (Env) trimer is covered by a glycan shield of ∼90 N-linked oligosaccharides, which comprises roughly half its mass and is a key component of HIV evasion from humoral immunity. To understand how antibodies can overcome the barriers imposed by the glycan shield, we crystallized fully glycosylated Env trimers from clades A, B, and G, visualizing the shield at 3.4-3.7 Å resolution. These structures reveal the HIV-1-glycan shield to comprise a network of interlocking oligosaccharides, substantially ordered by glycan crowding, that encase the protein component of Env and enable HIV-1 to avoid most antibody-mediated neutralization. The revealed features delineate a taxonomy of N-linked glycan-glycan interactions. Crowded and dispersed glycans are differently ordered, conserved, processed, and recognized by antibody. The structures, along with glycan-array binding and molecular dynamics, reveal a diversity in oligosaccharide affinity and a requirement for accommodating glycans among known broadly neutralizing antibodies that target the glycan-shielded trimer.


Subject(s)
HIV-1/chemistry , env Gene Products, Human Immunodeficiency Virus/chemistry , Antibodies, Neutralizing/metabolism , Antibodies, Viral/metabolism , Crystallography, X-Ray , Glycosylation , HIV-1/classification , HIV-1/immunology , Immune Evasion , Models, Molecular , Molecular Dynamics Simulation , Polysaccharides/analysis , Polysaccharides/metabolism
3.
Cell ; 165(2): 449-63, 2016 Apr 07.
Article in English | MEDLINE | ID: mdl-26949186

ABSTRACT

Antibodies with ontogenies from VH1-2 or VH1-46-germline genes dominate the broadly neutralizing response against the CD4-binding site (CD4bs) on HIV-1. Here, we define with longitudinal sampling from time-of-infection the development of a VH1-46-derived antibody lineage that matured to neutralize 90% of HIV-1 isolates. Structures of lineage antibodies CH235 (week 41 from time-of-infection, 18% breadth), CH235.9 (week 152, 77%), and CH235.12 (week 323, 90%) demonstrated the maturing epitope to focus on the conformationally invariant portion of the CD4bs. Similarities between CH235 lineage and five unrelated CD4bs lineages in epitope focusing, length-of-time to develop breadth, and extraordinary level of somatic hypermutation suggested commonalities in maturation among all CD4bs antibodies. Fortunately, the required CH235-lineage hypermutation appeared substantially guided by the intrinsic mutability of the VH1-46 gene, which closely resembled VH1-2. We integrated our CH235-lineage findings with a second broadly neutralizing lineage and HIV-1 co-evolution to suggest a vaccination strategy for inducing both lineages.


Subject(s)
AIDS Vaccines/immunology , Antibodies, Neutralizing/immunology , HIV Antibodies/immunology , HIV Infections/immunology , Amino Acid Sequence , Antibodies, Neutralizing/chemistry , B-Lymphocytes/immunology , HIV Antibodies/chemistry , HIV Envelope Protein gp120/immunology , HIV Infections/prevention & control , HIV-1/immunology , Humans , Models, Molecular , Molecular Sequence Data , Sequence Alignment
4.
Cell ; 161(6): 1280-92, 2015 Jun 04.
Article in English | MEDLINE | ID: mdl-26004070

ABSTRACT

The site on the HIV-1 gp120 glycoprotein that binds the CD4 receptor is recognized by broadly reactive antibodies, several of which neutralize over 90% of HIV-1 strains. To understand how antibodies achieve such neutralization, we isolated CD4-binding-site (CD4bs) antibodies and analyzed 16 co-crystal structures -8 determined here- of CD4bs antibodies from 14 donors. The 16 antibodies segregated by recognition mode and developmental ontogeny into two types: CDR H3-dominated and VH-gene-restricted. Both could achieve greater than 80% neutralization breadth, and both could develop in the same donor. Although paratope chemistries differed, all 16 gp120-CD4bs antibody complexes showed geometric similarity, with antibody-neutralization breadth correlating with antibody-angle of approach relative to the most effective antibody of each type. The repertoire for effective recognition of the CD4 supersite thus comprises antibodies with distinct paratopes arrayed about two optimal geometric orientations, one achieved by CDR H3 ontogenies and the other achieved by VH-gene-restricted ontogenies.


Subject(s)
Antibodies, Neutralizing/chemistry , Antibodies, Viral/chemistry , HIV Envelope Protein gp120/chemistry , HIV Envelope Protein gp120/metabolism , HIV-1/physiology , Amino Acid Sequence , Antibodies, Neutralizing/metabolism , Antibodies, Viral/metabolism , B-Lymphocytes/immunology , CD4 Antigens/metabolism , Complementarity Determining Regions , Epitopes, B-Lymphocyte , HIV Envelope Protein gp120/immunology , Humans , Models, Molecular , Molecular Sequence Data , Sequence Alignment
5.
Immunity ; 48(3): 500-513.e6, 2018 03 20.
Article in English | MEDLINE | ID: mdl-29548671

ABSTRACT

Virtually the entire surface of the HIV-1-envelope trimer is recognized by neutralizing antibodies, except for a highly glycosylated region at the center of the "silent face" on the gp120 subunit. From an HIV-1-infected donor, #74, we identified antibody VRC-PG05, which neutralized 27% of HIV-1 strains. The crystal structure of the antigen-binding fragment of VRC-PG05 in complex with gp120 revealed an epitope comprised primarily of N-linked glycans from N262, N295, and N448 at the silent face center. Somatic hypermutation occurred preferentially at antibody residues that interacted with these glycans, suggesting somatic development of glycan recognition. Resistance to VRC-PG05 in donor #74 involved shifting of glycan-N448 to N446 or mutation of glycan-proximal residue E293. HIV-1 neutralization can thus be achieved at the silent face center by glycan-recognizing antibody; along with other known epitopes, the VRC-PG05 epitope completes coverage by neutralizing antibody of all major exposed regions of the prefusion closed trimer.


Subject(s)
Antibodies, Neutralizing/immunology , HIV Antibodies/immunology , HIV Envelope Protein gp120/immunology , HIV Infections/immunology , HIV-1/immunology , Polysaccharides/immunology , Amino Acid Sequence , Antibodies, Neutralizing/chemistry , Antibodies, Neutralizing/genetics , Antibodies, Neutralizing/metabolism , Antigens, Viral/chemistry , Antigens, Viral/immunology , Binding Sites , Epitope Mapping , Epitopes/chemistry , Epitopes/immunology , Epitopes/metabolism , Glycopeptides/chemistry , Glycopeptides/immunology , Glycosylation , HIV Antibodies/chemistry , HIV Antibodies/genetics , HIV Antibodies/metabolism , HIV Envelope Protein gp120/chemistry , HIV Envelope Protein gp120/metabolism , Humans , Models, Molecular , Molecular Conformation , Polysaccharides/chemistry , Protein Binding/immunology , Somatic Hypermutation, Immunoglobulin/immunology , Structure-Activity Relationship
6.
Glycobiology ; 34(4)2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38263491

ABSTRACT

Modern glycoproteomics experiments require the use of search engines due to the generation of countless spectra. While these tools are valuable, manual validation of search engine results is often required for detailed analysis of glycopeptides as false-discovery rates are often not reliable for glycopeptide data. Near-isobaric mismatches are a common source of misidentifications for the popular glycopeptide-focused search engine pGlyco3.0, and in this technical note we share a strategy and script that improves the accuracy of the search utilizing two manually validated datasets of the glycoproteins CD16a and HIV-1 Env as proof-of-principle.


Subject(s)
Proteomics , Tandem Mass Spectrometry , Glycosylation , Proteomics/methods , Search Engine , Glycopeptides
7.
Proc Natl Acad Sci U S A ; 118(10)2021 03 09.
Article in English | MEDLINE | ID: mdl-33649208

ABSTRACT

Vaccine-based elicitation of broadly neutralizing antibodies holds great promise for preventing HIV-1 transmission. However, the key biophysical markers of improved antibody recognition remain uncertain in the diverse landscape of potential antibody mutation pathways, and a more complete understanding of anti-HIV-1 fusion peptide (FP) antibody development will accelerate rational vaccine designs. Here we survey the mutational landscape of the vaccine-elicited anti-FP antibody, vFP16.02, to determine the genetic, structural, and functional features associated with antibody improvement or fitness. Using site-saturation mutagenesis and yeast display functional screening, we found that 1% of possible single mutations improved HIV-1 envelope trimer (Env) affinity, but generally comprised rare somatic hypermutations that may not arise frequently in vivo. We observed that many single mutations in the vFP16.02 Fab could enhance affinity >1,000-fold against soluble FP, although affinity improvements against the HIV-1 trimer were more measured and rare. The most potent variants enhanced affinity to both soluble FP and Env, had mutations concentrated in antibody framework regions, and achieved up to 37% neutralization breadth compared to 28% neutralization of the template antibody. Altered heavy- and light-chain interface angles and conformational dynamics, as well as reduced Fab thermal stability, were associated with improved HIV-1 neutralization breadth and potency. We also observed parallel sets of mutations that enhanced viral neutralization through similar structural mechanisms. These data provide a quantitative understanding of the mutational landscape for vaccine-elicited FP-directed broadly neutralizing antibody and demonstrate that numerous antigen-distal framework mutations can improve antibody function by enhancing affinity simultaneously toward HIV-1 Env and FP.


Subject(s)
AIDS Vaccines/immunology , Broadly Neutralizing Antibodies/immunology , HIV Antibodies/immunology , HIV-1/immunology , Mutation , env Gene Products, Human Immunodeficiency Virus/immunology , AIDS Vaccines/genetics , Broadly Neutralizing Antibodies/genetics , HIV Antibodies/genetics , HIV-1/genetics , Humans , env Gene Products, Human Immunodeficiency Virus/genetics
8.
Mol Cancer ; 22(1): 152, 2023 09 09.
Article in English | MEDLINE | ID: mdl-37689715

ABSTRACT

BACKGROUND: Among digestive tract tumours, pancreatic ductal adenocarcinoma (PDAC) shows the highest mortality trend. Moreover, although PDAC metastasis remains a leading cause of cancer-related deaths, the biological mechanism is poorly understood. Recent evidence demonstrates that circular RNAs (circRNAs) play important roles in PDAC progression. METHODS: Differentially expressed circRNAs in normal and PDAC tissues were screened via bioinformatics analysis. Sanger sequencing, RNase R and actinomycin D assays were performed to confirm the loop structure of circEIF3I. In vitro and in vivo functional experiments were conducted to assess the role of circEIF3I in PDAC. MS2-tagged RNA affinity purification, mass spectrometry, RNA immunoprecipitation, RNA pull-down assay, fluorescence in situ hybridization, immunofluorescence and RNA-protein interaction simulation and analysis were performed to identify circEIF3I-interacting proteins. The effects of circEIF3I on the interactions of SMAD3 with TGFßRI or AP2A1 were measured through co-immunoprecipitation and western blotting. RESULTS: A microarray data analysis showed that circEIF3I was highly expressed in PDAC cells and correlated with TNM stage and poor prognosis. Functional experiments in vitro and in vivo revealed that circEIF3I accelerated PDAC cells migration, invasion and metastasis by increasing MMPs expression and activity. Mechanistic research indicated that circEIF3I binds to the MH2 domain of SMAD3 and increases SMAD3 phosphorylation by strengthening the interactions between SMAD3 and TGFßRI on early endosomes. Moreover, AP2A1 binds with circEIF3I directly and promotes circEIF3I-bound SMAD3 recruitment to TGFßRI on early endosomes. Finally, we found that circEif3i exerts biological functions in mice similar to those of circEIF3I in humans PDAC. CONCLUSIONS: Our study reveals that circEIF3I promotes pancreatic cancer progression. circEIF3I is a molecular scaffold that interacts with SMAD3 and AP2A1 to form a ternary complex, that facilitates the recruitment of SMAD3 to early endosomes and then activates the TGF-ß signalling pathway. Hence, circEIF3I is a potential prognostic biomarker and therapeutic target in PDAC.


Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Animals , Humans , Mice , Carcinoma, Pancreatic Ductal/genetics , Endosomes , In Situ Hybridization, Fluorescence , Pancreatic Neoplasms/genetics , RNA, Circular , Smad3 Protein/genetics , Transforming Growth Factor beta , Pancreatic Neoplasms
9.
J Transl Med ; 21(1): 903, 2023 Dec 11.
Article in English | MEDLINE | ID: mdl-38082307

ABSTRACT

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is characterized by rapid progression and poor prognosis. Understanding the genetic mechanisms that affect cancer properties and reprogram tumor immune microenvironment will develop new strategies to maximize the benefits for cancer therapies. METHODS: Gene signatures and biological processes associated with advanced cancer and unfavorable outcome were profiled using bulk RNA sequencing and spatial transcriptome sequencing, Caprin-1 was identified as an oncogenesis to expedite pancreatic cancer growth by activating autophagy. The mechanism of Caprin-1 inducing autophagy activation was further explored in vitro and in vivo. In addition, higher level of Caprin-1 was found to manipulate immune responses and inflammatory-related pathways. The immune profiles associated with increased levels of Caprin-1 were identified in human PDAC samples. The roles of CD4+T cells, CD8+T cells and tumor associated macrophages (TAMs) on clinical outcomes prediction were investigated. RESULTS: Caprin-1 was significantly upregulated in advanced PDAC and correlated with poor prognosis. Caprin-1 interacted with both ULK1 and STK38, and manipulated ULK1 phosphorylation which activated autophagy and exerted pro-tumorigenic phenotypes. Additionally, the infiltrated CD4+T cells and tumor associated macrophages (TAMs) were increased in Caprin-1High tissues. The extensive CD4+T cells determined poor clinical outcome in Caprin-1high patients, arguing that highly expressed Caprin-1 may assist cancer cells to escape from immune surveillance. CONCLUSIONS: Our findings establish causal links between the upregulated expression of Caprin-1 and autophagy activation, which may manipulate immune responses in PDAC development. Our study provides insights into considering Caprin-1 as potential therapeutic target for PDAC treatment.


Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Humans , Autophagy/genetics , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/pathology , Cell Line, Tumor , Immunity , Pancreatic Neoplasms/pathology , Protein Serine-Threonine Kinases , Tumor Microenvironment
10.
Can J Microbiol ; 69(12): 479-487, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37379574

ABSTRACT

The surface morphology of mature biofilms is heterogeneous and can be divided into concentric rings wrinkles (I), labyrinthine networks wrinkles (II), radial ridges wrinkles (III), and branches wrinkles (IV), according to surface wrinkle structure and distribution characteristics. Due to the wrinkle structures, channels are formed between the biofilm and substrate and transport nutrients, water, metabolic products, etc. We find that expansion rate variations of biofilms growing on substrates with high and low agar concentrations (1.5, 2.0, 2.5 wt.%) are not in the same phase. In the first 3 days' growth, the interaction stress between biofilm and each agar substrate increases, which makes the biofilm expansion rate decreases before wrinkle pattern IV (branches) comes up. After 3 days, in the later growth stage after wrinkle pattern IV appears, the biofilm has larger expansion rate growing on 2.0 wt.% agar concentration, which has the larger wrinkle distance in wrinkle pattern IV reducing energy consumption. Our study shows that the stiff substrate does not always inhibit the biofilm expansion, although it does in the earlier stage; after that, mature biofilms acquire larger expansion rate by adjusting the growth mode through the wrinkle evolution even in nutrient extremely depletion.


Subject(s)
Bacillus subtilis , Biofilms , Agar/metabolism , Bacillus subtilis/metabolism , Water/metabolism
11.
Can J Microbiol ; 69(7): 251-261, 2023 Jul 01.
Article in English | MEDLINE | ID: mdl-36893426

ABSTRACT

Material properties and growth environments affect the surface morphology of biofilms. Taken the biofilm growing in competitive environments as the object, which is compared with the single biofilm, we find that the competitive environment has an impact on the biofilm thickness and wrinkle patterns. Through diffusion-limited growth theoretical model analysis, it shows that the competitive environment is caused by cells competing for nutrition, and the competitive environment reacts on biofilms, which affect the phenotypic differentiation, causing changes in the stiffness of the biofilm. Using the theoretical and finite element simulation, we compare these results of bi-layer and tri-layer film-substrate models with experimental observations, and find that tri-layer film-substrate model is in line with the reality, which means that the layer between the biofilm and substrate plays an import role for wrinkle formation. Based on the above analysis, we further study effects of biofilm stiffness and interlayer thickness on wrinkles under competitive environment.


Subject(s)
Bacillus subtilis , Biofilms , Computer Simulation
12.
Indian J Microbiol ; 63(2): 197-207, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37325022

ABSTRACT

There is a 'coffee ring' in the Bacillus subtilis biofilm center, and the colony biofilm morphologies are distinct inside and outside the 'coffee ring'. In this paper, we study this morphological difference and explain the reasons of the 'coffee ring' formation and further the causes to the morphological variation. We developed a quantitative method to characterize the surface morphology, the outer area is thicker than the inner area of the 'coffee ring', and the thickness amplitude in outer area is larger than inner area of the 'coffee ring'. We adopt a logistic growth model to obtain how the environmental resistance influence the colony biofilm thickness. Dead cells provide gaps for stress release and make folds formation in colony biofilm. we developed a technique for optical imaging and matching cells with the BRISK algorithm to capture the distribution and movement of motile cells and matrix producing cells in the colony biofilm. Matrix producing cells are mainly distribute in the outside of the 'coffee ring', and the extracellular matrix (ECM) prevents the motile cells moving outward from center. Motile cells mainly locate inside the ring, a small amount of dead motile cells outside the 'coffee ring' give rise to radial folds formation. There are no ECM blocking cell movements inside the ring, which result in uniform folds formation. The distribution of ECM and different phenotypes lead to the formation of the 'coffee ring', which is verified by using eps and flagellar mutants.

13.
Cancer Sci ; 113(9): 2986-3001, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35534983

ABSTRACT

Emerging evidence has indicated that long noncoding RNAs (lncRNAs) are potential biomarkers and play crucial roles in cancer development. However, the functions and underlying mechanisms of lncRNA TPT1-AS1 in pancreatic ductal adenocarcinoma (PDAC) remain elusive. RNAseq data of PDAC tissues and normal tissues were analyzed, and lncRNAs which were associated with PDAC prognosis were identified. The clinical relevance of TPT1-AS1 for PDAC patients was explored, and the effects of TPT1-AS1 in PDAC progression were investigated in vitro and in vivo. LncRNA TPT1-AS1 was highly expressed in PDAC, and high TPT1-AS1 levels predicted a poor prognosis. Moreover, functional experiments revealed that TPT1-AS1 promoted pancreatic cancer cell proliferation, migration, invasion, and epithelial-to-mesenchymal transition (EMT) process in vitro and in vivo. Mechanistically, TPT1-AS1 functioned as an endogenous sponge for miR-30a-5p, which increased integrin ß3 (ITGB3) level in pancreatic cancer cells. Conversely, our data revealed that ITGB3 could activate the transcription factor signal transducer and activator of transcription 3 (STAT3), which in turn bound directly to the TPT1-AS1 promoter and affected the expression of TPT1-AS1, thus forming a positive feedback loop with TPT1-AS1. Taken together, our results uncovered a reciprocal loop of TPT1-AS1 and ITGB3 which contributed to pancreatic cancer growth and development, and indicated that TPT1-AS1 might serve as a novel potential diagnostic biomarker and therapeutic target for PDAC patients.


Subject(s)
Carcinoma, Pancreatic Ductal , MicroRNAs , Pancreatic Neoplasms , RNA, Long Noncoding , Carcinoma, Pancreatic Ductal/genetics , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Feedback , Gene Expression Regulation, Neoplastic , Humans , Integrin beta3/genetics , Integrin beta3/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Pancreatic Neoplasms
14.
J Transl Med ; 20(1): 86, 2022 02 12.
Article in English | MEDLINE | ID: mdl-35151320

ABSTRACT

BACKGROUND: Peroxisome proliferator-activated receptor-beta/delta (PPARδ) was considered as the key regulator involved in the evolution of various tumors. Given that PPARδ potential role in hepatocellular carcinoma (HCC) is still obscure, we comprehensively assessed its expression pattern, prognosis, functions and correlation with tumor microenvironment in HCC using public database data and in vitro studies. METHODS: Transcriptional data and clinical data in the TCGA and GEO database were analyzed in R software. Quantitative real-time polymerase chain reaction (qRT-PCR), western blotting and immunohistochemistry were used to detect the expression level of related RNA and proteins. The malignant biological characteristics were explored by cell counting Kit-8 (CCK8), 5-Ethynyl-2'-deoxyuridine (EdU) assay and wound healing assay. RESULTS: Our results illustrated that PPARδ expression was significantly higher in HCC tissues and HCC cell lines. Elevated expression of PPARδ suggested poor clinical staging and prognosis in HCC. Ligand-activated PPARδ expression promoted the proliferation and invasion of HCC cells via PDK1/AKT/GSK3ß signaling pathway. The expression of PPARδ was closely related to the HCC tumor microenvironment. CONCLUSIONS: PPARδ plays an important part in HCC progression, penetrating investigation of the related regulatory mechanism may shed light upon further biological and pharmacological value.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , PPAR delta , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Proliferation/genetics , Gene Expression Regulation, Neoplastic , Humans , Ligands , Liver Neoplasms/pathology , PPAR delta/genetics , PPAR delta/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction , Tumor Microenvironment
15.
J Virol ; 94(13)2020 06 16.
Article in English | MEDLINE | ID: mdl-32295908

ABSTRACT

HIV-1 envelope (Env) trimers, stabilized in a prefusion-closed conformation, can elicit humoral responses capable of neutralizing HIV-1 strains closely matched in sequence to the immunizing strain. One strategy to increase elicited neutralization breadth involves vaccine priming of immune responses against a target site of vulnerability, followed by vaccine boosting of these responses with prefusion-closed Env trimers. This strategy has succeeded at the fusion peptide (FP) site of vulnerability in eliciting cross-clade neutralizing responses in standard vaccine-test animals. However, the breadth and potency of the elicited responses have been less than optimal. Here, we identify three mutations (3mut), Met302, Leu320, and Pro329, that stabilize the apex of the Env trimer in a prefusion-closed conformation and show antigenically, structurally, and immunogenically that combining 3mut with other approaches (e.g., repair and stabilize and glycine-helix breaking) yields well-behaved clade C-Env trimers capable of boosting the breadth of FP-directed responses. Crystal structures of these trimers confirmed prefusion-closed apexes stabilized by hydrophobic patches contributed by Met302 and Leu320, with Pro329 assuming canonically restricted dihedral angles. We substituted the N-terminal eight residues of FP (FP8, residues 512 to 519) of these trimers with the second most prevalent FP8 sequence (FP8v2, AVGLGAVF) and observed a 3mut-stabilized consensus clade C-Env trimer with FP8v2 to boost the breadth elicited in guinea pigs of FP-directed responses induced by immunogens containing the most prevalent FP8 sequence (FP8v1, AVGIGAVF). Overall, 3mut can stabilize the Env trimer apex, and the resultant apex-stabilized Env trimers can be used to expand the neutralization breadth elicited against the FP site of vulnerability.IMPORTANCE A major hurdle to the development of an effective HIV-1 vaccine is the elicitation of serum responses capable of neutralizing circulating strains of HIV, which are extraordinarily diverse in sequence and often highly neutralization resistant. Recently, we showed how sera with 20 to 30% neutralization breadth could, nevertheless, be elicited in standard vaccine test animals by priming with the most prevalent N-terminal 8 residues of the HIV-1 fusion peptide (FP8), followed by boosting with a stabilized BG505-envelope (Env) trimer. Here, we show that subsequent boosting with a 3mut-apex-stabilized consensus C-Env trimer, modified to have the second most prevalent FP8 sequence, elicits higher neutralization breadth than that induced by continued boosting with the stabilized BG505-Env trimer. With increased neutralizing breadth elicited by boosting with a heterologous trimer containing the second most prevalent FP8 sequence, the fusion peptide-directed immune-focusing approach moves a step closer toward realizing an effective HIV-1 vaccine regimen.


Subject(s)
AIDS Vaccines/immunology , env Gene Products, Human Immunodeficiency Virus/genetics , env Gene Products, Human Immunodeficiency Virus/immunology , Animals , Antibodies, Neutralizing/immunology , Female , Guinea Pigs , HEK293 Cells , HIV Antibodies/immunology , HIV Seropositivity , HIV-1/immunology , Humans , Immunization, Secondary , Peptides , Vaccines, Subunit
16.
FASEB J ; 34(2): 2524-2540, 2020 02.
Article in English | MEDLINE | ID: mdl-31908026

ABSTRACT

The main mechanism of hyaluronidase 1(HYAL-1) in the development of postoperative pancreatic fistula (POPF) after pancreatoduodenectomy (PD) was unknown. In this study, a comprehensive inventory of pre-, intra-, and postoperative clinical and biological data of two cohorts (62 pancreatic cancer [PCa] and 111 pancreatic ductal adenocarcinoma [PDAC]) which could induce POPF were retrospectively analyzed. Then, a total of 7644 genes correlated with HYAL-1 was predicted in PDAC tissues and the enriched pathway, kinase targets and biological process of those correlated genes were evaluated. Finally, a mouse pancreatic fistula (PF) model was first built and in vitro studies were performed to investigate the effects of HYAL-1 on PF progression. Our data indicated that preoperative serum HYAL-1 level, pancreatic fibrosis score, and pancreatic duct size were valuable factors for detecting POPF of Grade B and C. The serum HYAL-1 level of 2.07 mg/ml and pancreatic fibrosis score of 2.5 were proposed as the cutoff values for indicating POPF. The bioinformatic analysis and in vitro and in vivo studies demonstrated that HYAL-1 facilitates pancreatic acinar cell autophagy via the dephosphorylation of adenosine 5'-monophosphate-activated protein kinase (AMPK) and signal transducers and activators of transcription 3 (STAT3) signaling pathways, which exacerbate pancreatic secretion and inflammation. In summary, the preoperative serum HYAL-1 was a significant predictor for POPF in patients who underwent PD. Tumor-induced HYAL-1 is one of core risk in accelerating PF and then promoting pancreatic secretion and acute inflammation response through the AMPK and STAT3-induced autophagy.


Subject(s)
Autophagy/physiology , Hyaluronoglucosaminidase/blood , Pancreatic Fistula/pathology , Pancreaticoduodenectomy , Adult , Aged , Carcinoma, Pancreatic Ductal/pathology , Carcinoma, Pancreatic Ductal/surgery , Female , Humans , Intestines/pathology , Male , Middle Aged , Pancreas/pathology , Pancreatic Fistula/diagnosis , Pancreatic Fistula/surgery , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/surgery , Pancreaticoduodenectomy/methods , Retrospective Studies , Risk Factors , Pancreatic Neoplasms
17.
Immunol Invest ; 50(4): 389-398, 2021 May.
Article in English | MEDLINE | ID: mdl-32506984

ABSTRACT

Background: The cross-reactive allergen between mugwort (Artemisia vulgaris) and kidney bean (Phaseolus vulgaris) has not yet been identified.Methods: A total of 24 patients were included in this study. The sera of patients were analyzed for the concentrations of specific IgE antibodies. The allergenicity and cross-reactivity were investigated by Western blotting and immunoblot inhibitory experiments.Results: The immunoblotting indicated the binding of patients' IgE to crude mugwort extract at ~26 kDa protein (15 cases), ~60 kDa (15 cases), and 10-15 kDa proteins (12 cases). The results of the immunoblot-inhibition assay showed that kidney bean seed extract inhibited specific IgE binding to mugwort at 10-15 kDa, ~26 kDa, and ~60 kDa in 4 (16.7%), 1 (4.2%) and 2 (8.3%) cases, respectively. On the other hand, mugwort extract was demonstrated to inhibit specific IgE binding to kidney bean seed at 10-15 kDa, 15-20 kDa, ~30 kDa, and 60 kDa in 1 (4.2%), 3 (12.5%), 4 (16.7%), and 3 (12.5%) cases, respectively.Conclusion: The 26-30 kDa, 10-15 kDa, and 60 kDa proteins are potential causative agents of the cross-reactivity between mugwort and kidney beans. The findings of this study improved the current understanding on the allergenicity of kidney beans and would provide insights into the refinement of treatment strategy for anaphylaxis.


Subject(s)
Allergens/immunology , Anaphylaxis/immunology , Antigens, Plant/immunology , Artemisia/immunology , Exercise , Phaseolus/immunology , Pollen/immunology , Rhinitis, Allergic, Seasonal/immunology , Anaphylaxis/blood , Cross Reactions , Humans , Immunoglobulin E/blood , Plant Extracts/immunology , Rhinitis, Allergic, Seasonal/blood , Seeds/immunology
18.
Biomed Eng Online ; 20(1): 67, 2021 Jul 03.
Article in English | MEDLINE | ID: mdl-34217312

ABSTRACT

Hepatocellular carcinoma (HCC) is currently the sixth most common malignancy and the second major cause of tumor-related deaths in the world. This study aimed to investigate the role of cleavage and polyadenylation factor-6 (CPSF6) and B-cell translocation gene 2 (BTG2) in regulating the glycolysis and apoptosis in HCC cells. The RNA and protein expression of CPSF6 and BTG2 in normal hepatocyte and HCC were, respectively, detected by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) analysis and Western blot analysis. The viability and apoptosis of transfected Huh-7 cells were, respectively, analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) assay. The expression of apoptosis-related proteins and HK-2 in transfected Huh-7 cells was also detected by Western blot analysis. The levels of glucose and lactate in the culture supernatant of transfected Huh-7 cells were, respectively, detected with the glucose assay kit and lactate assay kit. The interaction of CPSF6 and BTG2 was confirmed by RNA binding protein immunoprecipitation (RIP) assay. As a result, CPSF6 expression was increased while BTG2 expression was decreased in Huh-7 cells. Interference with CPSF6 suppressed the viability and glycolysis, and promoted the apoptosis of Huh-7 cells. Furthermore, CPSF6 interacted with BTG2 and interference with CPSF6 upregulated the BTG2 expression and inhibited the protein kinase B (AKT)/extracellular signal-regulated kinase (ERK)/nuclear factor (NF)-κB pathway. Interference with BTG2 could partially reverse the above cell changes caused by interference with CPSF6. In conclusion, CPSF6 inhibited the BTG2 expression to promote glycolysis and suppress apoptosis in HCC cells by activating AKT/ERK/NF-κB pathway.


Subject(s)
Carcinoma, Hepatocellular , Immediate-Early Proteins , Liver Neoplasms , Apoptosis , Carcinoma, Hepatocellular/genetics , Carrier Proteins , Cell Line, Tumor , Cell Proliferation , Glycolysis , Humans , Immediate-Early Proteins/genetics , Immediate-Early Proteins/metabolism , Liver Neoplasms/genetics , RNA , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolism , mRNA Cleavage and Polyadenylation Factors
19.
Entropy (Basel) ; 23(1)2021 Jan 08.
Article in English | MEDLINE | ID: mdl-33429980

ABSTRACT

The thermochemical sulfur-iodine cycle is a potential method for hydrogen production, and the hydrogen iodide (HI) decomposition is the key step to determine the efficiency of hydrogen production in the cycle. To further reduce the irreversibility of various transmission processes in the HI decomposition reaction, a one-dimensional plug flow model of HI decomposition tubular reactor is established, and performance optimization with entropy generate rate minimization (EGRM) in the decomposition reaction system as an optimization goal based on finite-time thermodynamics is carried out. The reference reactor is heated counter-currently by high-temperature helium gas, the optimal reactor and the modified reactor are designed based on the reference reactor design parameters. With the EGRM as the optimization goal, the optimal control method is used to solve the optimal configuration of the reactor under the condition that both the reactant inlet state and hydrogen production rate are fixed, and the optimal value of total EGR in the reactor is reduced by 13.3% compared with the reference value. The reference reactor is improved on the basis of the total EGR in the optimal reactor, two modified reactors with increased length are designed under the condition of changing the helium inlet state. The total EGR of the two modified reactors are the same as that of the optimal reactor, which are realized by decreasing the helium inlet temperature and helium inlet flow rate, respectively. The results show that the EGR of heat transfer accounts for a large proportion, and the decrease of total EGR is mainly caused by reducing heat transfer irreversibility. The local total EGR of the optimal reactor distribution is more uniform, which approximately confirms the principle of equipartition of entropy production. The EGR distributions of the modified reactors are similar to that of the reference reactor, but the reactor length increases significantly, bringing a relatively large pressure drop. The research results have certain guiding significance to the optimum design of HI decomposition reactors.

20.
BMC Bioinformatics ; 21(1): 159, 2020 Apr 29.
Article in English | MEDLINE | ID: mdl-32349677

ABSTRACT

BACKGROUND: Genomic islands are associated with microbial adaptations, carrying genomic signatures different from the host. Some methods perform an overall test to identify genomic islands based on their local features. However, regions of different scales will display different genomic features. RESULTS: We proposed here a novel method "2SigFinder ", the first combined use of small-scale and large-scale statistical testing for genomic island detection. The proposed method was tested by genomic island boundary detection and identification of genomic islands or functional features of real biological data. We also compared the proposed method with the comparative genomics and composition-based approaches. The results indicate that the proposed 2SigFinder is more efficient in identifying genomic islands. CONCLUSIONS: From real biological data, 2SigFinder identified genomic islands from a single genome and reported robust results across different experiments, without annotated information of genomes or prior knowledge from other datasets. 2SigHunter identified 25 Pathogenicity, 1 tRNA, 2 Virulence and 2 Repeats from 27 Pathogenicity, 1 tRNA, 2 Virulence and 2 Repeats, and detected 101 Phage and 28 HEG out of 130 Phage and 36 HEGs in S. enterica Typhi CT18, which shows that it is more efficient in detecting functional features associated with GIs.


Subject(s)
Algorithms , Genome, Bacterial , Genomic Islands/genetics , Genomics/methods , Pseudomonas aeruginosa/genetics , Pseudomonas aeruginosa/pathogenicity , Salmonella enterica/genetics , Salmonella enterica/pathogenicity , Virulence
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