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1.
J Mater Chem B ; 10(48): 9974-9983, 2022 12 14.
Article in English | MEDLINE | ID: mdl-36398620

ABSTRACT

Triangular gold nanoplates (TAuNPs) were prepared by a one-step rapid growth method and then reduced and stabilized on two-dimensional nano mica nanoplatelets (NMPs). We also prepared TAuNP/NMP nanohybrids with a three-dimensional lightning-rod effect by oxidative etching. The surface of the delaminated NMPs (only 1 nm thick) is highly charged and can provide a large specific surface area; thus, it can be used as a substrate for the stable growth of gold nanoplates. In addition, by controlling relevant synthesis parameters, the edge length of the TAuNPs can be easily adjusted in the range of 30-90 nm. During reduction of the TAuNPs, the cationic surfactant cetyltrimethylammonium chloride was added as a protective agent to surround the TAuNPs; consequently, the surface was positively charged, which facilitates adsorption for detecting molecules with negative charges. When nanohybrids were used in surface-enhanced Raman spectroscopy (SERS) to detect adenine molecules, the limit of detection concentration was 10-9 M. The Raman enhancement factor was 5.7 × 107, and the relative standard deviation (RSD) was 9.8%. Finally, this method was applied to the biological detection of Staphylococcus aureus, and the surface charge and hydrophilic properties of the material significantly improved the SERS signal of S. aureus. The limit of detection concentration was 102 CFU mL-1, and the RSD was 11.2%. The TAuNP/NMP nanohybrids can provide very rapid and sensitive SERS detection of biomolecules.


Subject(s)
Lightning , Metal Nanoparticles , Gold/chemistry , Metal Nanoparticles/chemistry , Staphylococcus aureus , Spectrum Analysis, Raman/methods , Bacteria
2.
ACS Omega ; 7(45): 41815-41826, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-36406539

ABSTRACT

Gold nanorods (AuNRs) with different aspect ratios were prepared by the seed-mediated growth method and combined with three carbon-based nanomaterials of multiple dimensions (i.e., zero-dimensional (0D) carbon black (CB), one-dimensional (1D) carbon nanotubes (CNTs), and two-dimensional (2D) graphene oxide (GO)). The AuNR/carbon-based nanomaterial hybrids were utilized in dynamic surface-enhanced Raman scattering (D-SERS). First, cetyltrimethylammonium bromide (CTAB) was used to stabilize and coat the AuNRs, enabling them to be dispersed in water and conferring a positive charge to the surface. AuNR/carbon-based nanomaterial hybrids were then formed via electrostatic attraction with the negatively charged carbon-based nanomaterials. Subsequently, the AuNR/carbon-based nanomaterial hybrids were utilized as large-area and highly sensitive Raman spectroscopy substrates. The AuNR/GO hybrids afforded the best signal enhancement because the thickness of GO was less than 5 nm, which enabled the AuNRs adsorbed on GO to produce a good three-dimensional hotspot effect. The enhancement factor (EF) of the AuNR/GO hybrids for the dye molecule Rhodamine 6G (R6G) reached 1 × 107, where the limit of detection (LOD) was 10-8 M. The hybrids were further applied in D-SERS (detecting samples transitioning from the wet state to the dry state). During solvent evaporation, the system spontaneously formed many hotspots, which greatly enhanced the SERS signal. The final experimental results demonstrated that the AuNR/GO hybrids afforded the best D-SERS signal enhancement. The EF value for R6G reached 1.1 × 108 after 27 min, with a limit of detection of 10-9 M at 27 min. Therefore, the AuNR/GO nanohybrids have extremely high sensitivity as molecular sensing elements for SERS and are also very suitable for the rapid detection of single molecules in water quality and environmental management.

3.
ACS Appl Bio Mater ; 5(3): 1073-1083, 2022 03 21.
Article in English | MEDLINE | ID: mdl-35195391

ABSTRACT

A flexible hybrid substrate was developed by affixing gold nanoparticles (AuNPs) onto the surface of two-dimensional nanomica platelets (NMPs). The substrate was successfully used in biosensors with high efficiency and high selectivity through surface-enhanced Raman scattering (SERS). By controlling the amphiphilicity of the hybrid substrate, the flexible substrate was made highly selective toward biomolecules. Four different SERS substrate systems were constructed, including intercalated mica, exfoliated NMPs, hydrophilic exfoliated NMPs, and hydrophobic exfoliated NMPs. NMPs were only 1 nm thick. AuNPs adsorbed on both sides of NMPs and thus created excellent three-dimensional hot junction effects in the z-axis direction. For the detection of adenine in DNA, a satisfactory Raman enhancement factor (EF) of up to 8.9 × 106 was achieved with the detection limit as low as 10-8 M. Subsequently, the AuNP/NMP hybrids were adopted to rapidly detect hydrophilic Staphylococcus hominis and hydrophobic Escherichia coli. The AuNP/PIB-POE-PIB/NMP nanohybrid was concurrently hydrophilic and hydrophobic. This amphiphilic property greatly enhanced the detection selectivity and signal intensity for hydrophilic or hydrophobic bacteria. Overall, AuNPs/PIB-POE-PIB/NMPs developed as SERS substrates enable rapid, sensitive biodetection.


Subject(s)
Metal Nanoparticles , Spectrum Analysis, Raman , Blood Platelets , Gold/chemistry , Hydrophobic and Hydrophilic Interactions , Metal Nanoparticles/chemistry , Spectrum Analysis, Raman/methods
5.
Mol Immunol ; 136: 55-64, 2021 08.
Article in English | MEDLINE | ID: mdl-34087624

ABSTRACT

Pseudorabies virus (PRV) is an enveloped double-stranded DNA virus that is the etiological agent of Aujeszky's disease in pigs. Vaccination is currently available to prevent PRV infection, but there is still an urgent need for new strategies to control this infectious disease. Histone deacetylases (HDACs) are epigenetic regulators that regulate the histone tail, chromatin conformation, protein-DNA interaction and even transcription. Viral transcription and protein activities are intimately linked to regulation by histone acetyltransferases and HDACs that remodel chromatin and regulate gene expression. We reported here that genetic and pharmacological inhibition of HDAC1 significantly influenced PRV replication. Moreover, we demonstrated that inhibition of HDAC1 induced a DNA damage response and antiviral innate immunity. Mechanistically, the HDAC1 inhibition-induced DNA damage response resulted in the release of double-strand DNA into the cytosol to activate cyclic GMP-AMP synthase and the downstream STING/TBK1/IRF3 innate immune signaling pathway. Our results demonstrate that an HDAC1 inhibitor may be used as a new strategy to prevent Aujeszky's disease in pigs.


Subject(s)
Herpesvirus 1, Suid/drug effects , Histone Deacetylase 1/antagonists & inhibitors , Histone Deacetylase Inhibitors/pharmacology , Hydroxamic Acids/pharmacology , Pseudorabies/drug therapy , 3T3 Cells , Animals , Cell Line , DNA Damage/drug effects , DNA Repair/genetics , HEK293 Cells , Herpesvirus 1, Suid/growth & development , Histone Deacetylase 1/genetics , Humans , Immunity, Innate/drug effects , Immunity, Innate/immunology , Membrane Proteins/metabolism , Mice , Nucleotidyltransferases/metabolism , Pseudorabies/immunology , RAW 264.7 Cells , RNA Interference , RNA, Small Interfering/genetics , Swine , Swine Diseases/virology , Virus Replication/drug effects
6.
Curr Top Med Chem ; 21(14): 1235-1250, 2021 Oct 05.
Article in English | MEDLINE | ID: mdl-34145995

ABSTRACT

BACKGROUND: Virus-like Particles (VLPs) are non-genetic multimeric nanoparticles synthesized through in vitro or in vivo self-assembly of one or more viral structural proteins. Immunogenicity and safety of VLPs make them ideal candidates for vaccine development and efficient nanocarriers for foreign antigens or adjuvants to activate the immune system. AIMS: The present study aimed to design and synthesize a chimeric VLP vaccine of the phage Qbeta (Qß) coat protein presenting the universal epitope of the coronavirus. METHODS: The RNA phage Qß coat protein was designed and synthesized, denoted as Qbeta. The CoV epitope, a universal epitope of coronavirus, was inserted into the C-terminal of Qbeta using genetic recombination, designated as Qbeta-CoV. The N-terminal of Qbeta-CoV was successively inserted into the TEV restriction site using mCherry red fluorescent label and modified affinity purified histidine label 6xHE, which was denoted as HE-Qbeta-CoV. Isopropyl ß-D-1-thiogalactopyranoside (IPTG) assessment revealed the expression of Qbeta, Qbeta-CoV, and HE-Qbeta-CoV in the BL21 (DE3) cells. The fusion protein was purified by salting out using ammonium sulfate and affinity chromatography. The morphology of particles was observed using electron microscopy. The female BALB/C mice were immunized intraperitoneally with the Qbeta-CoV and HE-Qbeta-- CoV chimeric VLPs vaccines and their sera were collected for the detection of antibody level and antibody titer using ELISA. The serum is used for the neutralization test of the three viruses of MHV, PEDV, and PDCoV. RESULTS: The results revealed that the fusion proteins Qbeta, Qbeta-CoV, and HE-Qbeta-CoV could all obtain successful expression. Particles with high purity were obtained after purification; the chimeric particles of Qbeta-CoV and HE-Qbeta-CoV were found to be similar to Qbeta particles in morphology and formed chimeric VLPs. In addition, two chimeric VLP vaccines induced specific antibody responses in mice and the antibodies showed certain neutralizing activity. CONCLUSION: The successful construction of the chimeric VLPs of the phage Qß coat protein presenting the universal epitope of coronavirus provides a vaccine form with potential clinical applications for the treatment of coronavirus disease.


Subject(s)
Antibodies, Neutralizing/immunology , Capsid Proteins/immunology , Coronavirus/immunology , Vaccines, Virus-Like Particle/immunology , Animals , Antigens, Viral/genetics , Antigens, Viral/immunology , Enzyme-Linked Immunosorbent Assay , Female , Mice, Inbred BALB C , Microscopy, Electron, Scanning , Phylogeny , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/isolation & purification , Recombinant Fusion Proteins/metabolism , Vaccines, Virus-Like Particle/genetics , Viral Proteins/genetics
7.
Front Immunol ; 11: 575818, 2020.
Article in English | MEDLINE | ID: mdl-33072119

ABSTRACT

Pigs have anatomical and physiological characteristics comparable to those in humans and, therefore, are a favorable model for immune function research. Interferons (IFNs) and inflammasomes have essential roles in the innate immune system. Here, we report that G10, a human-specific agonist of stimulator of interferon genes (STING), activates both type I IFN and the canonical NLRP3 inflammasome in a STING-dependent manner in porcine cells. Without a priming signal, G10 alone transcriptionally stimulated Sp1-dependent p65 expression, thus triggering activation of the nuclear factor-κB (NF-κB) signaling pathway and thereby priming inflammasome activation. G10 was also found to induce potassium efflux- and NLRP3/ASC/Caspase-1-dependent secretion of IL-1ß and IL-18. Pharmacological and genetic inhibition of NLRP3 inflammasomes increased G10-induced type I IFN expression, thereby preventing virus infection, suggesting negative regulation of the NLRP3 inflammasome in the IFN response in the context of STING-mediated innate immune activation. Overall, our findings reveal a new mechanism through which G10 activates the NLRP3 inflammasome in porcine cells and provide new insights into STING-mediated innate immunity in pigs compared with humans.


Subject(s)
Immunity, Innate/drug effects , Inflammasomes/agonists , Interferon Type I/metabolism , Membrane Proteins/agonists , NLR Family, Pyrin Domain-Containing 3 Protein/agonists , Thiazines/pharmacology , Animals , CARD Signaling Adaptor Proteins/metabolism , Caspase 1/metabolism , Chlorocebus aethiops , HEK293 Cells , Humans , Inflammasomes/genetics , Inflammasomes/immunology , Inflammasomes/metabolism , Interferon Type I/genetics , Membrane Proteins/genetics , Membrane Proteins/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , NLR Family, Pyrin Domain-Containing 3 Protein/immunology , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Signal Transduction , Sp1 Transcription Factor/genetics , Sp1 Transcription Factor/metabolism , Sus scrofa , THP-1 Cells , Transcription Factor RelA/genetics , Transcription Factor RelA/metabolism , Vero Cells
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