Viral immunology最新文献

Viral infections are ubiquitous, and their prevention and treatment have become a great challenge. Steroids have different biological activities, including antiviral activity, which is related to steroid structural diversity. With the intensive study of steroids, it has been found that steroids can interfere with almost any step of the viral life cycle to exert antiviral activity. In this article, we review the antiviral activity and mechanism of action of steroids and their derivatives against a range of human viruses and conclude that natural steroids and their derivatives are very promising antiviral drug candidates that deserve further study to elucidate their pharmacological potential.

Interferon (IFN) is a pivotal agent against hepatitis B virus (HBV) in clinic, but there is a lack of accurate biomarkers to predict the response to IFN therapy in patients with chronic hepatitis B (CHB). Our study aimed to investigate potential targets for IFN therapy and to explore the network of interactions associated with IFN response. MicroRNA (miRNA) (GSE29911) and messenger RNA (GSE27555) datasets were used to screen the differentially expressed miRNAs (DEmiRNAs) and differentially expressed genes (DEGs). The random forest and k-nearest neighbors algorithm were used to further screen the core DEmiRNAs and build a prediction model. A Protein-Protein Interaction (PPI) network based on the STRING database was constructed and visualized by the Cytoscape software. Then, we collected transcription factors (TFs) from the TransmiR database to construct the TF-miRNA-hub gene regulatory network. Finally, real-time quantitative polymerase chain reaction was used to verify the expression of four miRNAs in HepG2-NTCP and Huh-7, and the effect of IFN treatment on four miRNAs' expression was preliminarily explored. Eighteen DEmiRNAs in GSE29911 and 700 DEGs in GSE27555 were identified. Boruta feature selection identified four miRNAs (miR-873, miR-200a, miR-30b, and let-7g) from 18 DEmiRNAs. We identified 48 TFs, 4 miRNAs, and 10 hub genes and constructed a TF-miRNA-hub gene network to suggest the mechanism of IFN response. According to the experimental results, miR-873 was upregulated and IFN treatment could inhibit it in HBV-transfected cells (p < 0.05). We constructed a TF-miRNA-hub gene regulatory network, and our results demonstrate that miR-873 was identified as a potential biomarker of IFN response in patients with CHB. This information provides an initial basis for understanding the complex IFN response regulatory mechanisms.

People living with HIV (PLWH) beginning antiretroviral therapy (ART) retain a high burden of cytomegalovirus (CMV). CMV has been implicated in atherosclerosis in healthy adults, and a role in PLWH is plausible. Atherosclerosis has also been linked with γδ T cells and CMV seropositivity with altered γδ T cell profiles in other populations. In our cohort of PLWH starting ART in Jakarta (Indonesia), metrics of the CMV burden correlated with altered profiles of Vδ2^- γδ T cells. Here CMV DNA was sought by RT-PCR as PLWH began ART. γδ T cell subsets were immunophenotyped using flow cytometry, and CMV-reactive antibodies were quantitated by ELISA after fixed intervals on ART. Carotid intima-media thickness (cIMT) was used to assess atherosclerosis. PLWH retained higher levels of CMV-reactive antibody than healthy controls (p = 0.001-0.04), and 50% began ART with detectable CMV DNA. cIMT values rose between 6 and 12 months on ART. At 6 months, cIMT correlated with CMV-reactive antibodies and proportions of activated Vδ2^- γδ T cells (r = 0.56-0.57; p = 0.035-0.042) in PLWH who began ART with detectable CMV DNA. Hence, a high burden of replicating CMV may promote atherosclerosis in PLWH after a period on ART, and the role of activated Vδ2^- γδ T cells warrants further study.

Chronic hepatitis C virus (HCV) infection poses a major health risk worldwide, with patients susceptible to liver cirrhosis and hepatocellular carcinoma. This study focuses on the development of effective therapeutic strategies for HCV infection through the investigation of immunogenic properties of a DNA construct based on the NS3/4A gene of HCV genotype (g)3a. Gene expression of the mutagenized (mut) NS3/4A target genes was assessed through reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blot analysis. Additionally, bioinformatics tools were employed to evaluate the impact of the mut-NS3/4A-based DNA vaccine. Analysis revealed increased mut-NS3/4A mRNA levels and target protein abundance compared with the native sequence. Elevated mut-NS3/NS4A levels could result from increased RNA stability and proper protein folding. Physicochemical analyses of the protein demonstrated favorable attributes such as thermostability and solubility. Three-dimensional mut-NS3/4A protein modeling confirmed its high stability and agreement with known protein structures. Additionally, potential immunogenic regions of both T and B cell epitopes were discovered based on peptide binding to major histocompatibility complex molecules of Asian origin. Importantly, these epitopes exhibited nonallergenic and nontoxic characteristics. These findings highlight the potential of the NS3/4A-based DNA construct as a promising candidate for an HCVg3a vaccine tailored for the Asian population, providing valuable insights for future immunotherapeutic approaches.

Respiratory syncytial virus (RSV) is one of the most important etiologies of acute respiratory infections that cause bronchiolitis in children under 5 years of age. Treatments are expensive, no vaccine is available, and this is an important cause of hospitalization. Costimulatory molecules have been reported to be good inducers of antiviral type 1 immune response. This study aimed to generate a recombinant vaccine with the RSV F protein fused to 4-1BBL to evaluate the activation of an antiviral response in vitro and the production of neutralizing antibodies in vivo. The codon-optimized F gene was subcloned into an expression vector as follows: streptavidin core, gene F, and costimulatorytumor necrosis factor receptor superfamily member 9 -TNFRS9- ligand (4-1BBL). After the induction of expression in Escherichia coli C43, the recombinant protein (SA-F3x-4-1BBL, denominated SF4) was purified and verified by western blotting. Cultured RAW264.7 macrophages were stimulated with SF4 protein, then tumor necrosis factor (TNF) receptor-associated factor 2 (TRAF2), p38, and nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) were analyzed by western blot, and mRNA cytokines were analyzed by RT-qPCR. Finally, male C57BL/6 mice were inoculated with SF4, and the generation of anti-RSV neutralizing antibodies and serum cytokines was examined. SF4 had a size of 84.4 kDa with a 5.6% yield. SA-F-4-1BBL upregulated TRAF2, TNF-α, and interferon (IFN)-γ expression levels and activated p38 mitogen-activated protein kinase and NF-κΒ pathways in RAW264.7 cells. Importantly, antibodies capable of neutralizing RSV infection and producing type 1 cytokines were detected in the sera of immunized animals. These results suggest that the fusion protein SF4 activates the 4-1BBL signaling pathway, resulting in an effective antiviral response mediated by neutralizing antibodies and antiviral cytokines.

The increasing use of immune suppressive monoclonal antibodies in the treatment of organ transplant recipients and patients with oncologic, neurological, and autoimmune diseases can lead to serious morbidity and mortality from the reactivation of viral agents that persist in humans. The squirrel monkey polyomaviruses are naturally found in Bolivian squirrel monkeys (SQM) and may be a useful model for the study of polyomavirus-associated pathogenesis and experimental treatment and prevention strategies. Two diverse groups of squirrel monkeys were given, a single dose of an anti-B cell antibody (rituximab) resulting in complete depletion of B cells (CD20+), while an anti-CD8 monoclonal antibody (7 pt-3F9) resulted in a transient depletion of CD8+ lymphocytes compared with control animals (group with no infusion with either of the monoclonal antibodies). The animals remained clinically healthy, with no pathological symptoms suggesting that the intensity and/or duration of immune suppression were inadequate to trigger pathogenic reactivation of the latent polyoma and herpes viruses. We observed a transient reduction in circulating plasma cytokines, IL-2, IFN-γ, and IL-12 reduced JC and BK viral protein-specific proliferative responses in both the CD8 and CD20 depletion groups. This study clearly elucidates the consequences of the use of depletion monoclonal antibodies in immune suppression modalities in the treatment of human malignancies and during transplantation, and SQM acts as a good model in the selection of dosage at which activation of latent viruses is at a minimum, with no pathological consequences.

This study aims to evaluate the estimate of causal relationship between Epstein-Barr virus (EBV) antibody levels and autoimmune diseases (AIDs), such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), through bidirectional two-sample Mendelian randomization (MR) analysis. Despite 50 years of research into the link between EBV infection and AIDs, inconsistent results persist due to the complex mechanisms of EBV within the body. We utilized large-scale genome-wide association studies (GWAS) data from the Integrative Epidemiology Unit (IEU) Open GWAS Project database to conduct rigorous MR analysis, incorporating various sensitivity analyses to assess potential impacts and ensure robustness. EBV antibodies (including VCA-IgG, ZEBRA-IgG, EBNA-1-IgG, and EA-D-IgG) were used as exposure variables, whereas RA and SLE served as outcome variables. In the reverse analysis, RA and SLE were treated as exposure variables and EBV antibodies as outcome variables. When EBV antibodies are designated as the exposure variables, the random-effects inverse-variance weighted (IVW) analysis indicated a significant negative genetic causal relationship between EBV EA-D antibody levels and RA (p = 0.007, odds ratio [OR] = 0.700, 95% confidence interval [CI] = [0.539-0.907]). No significant genetic causal relationship was found between SLE and EBV antibody levels. When RA and SLE are designated as the exposure variables, the random-effects IVW analysis revealed significant positive genetic causal relationships between SLE and EBV ZEBRA antibody levels (p = 0.009, OR = 1.028, 95% CI = [1.007-1.050]) and EBV EA-D antibody levels (p = 0.005, OR = 1.032, 95% CI = [1.009-1.054]). No significant genetic causal relationship was observed between RA and EBV antibody levels. This study offers compelling evidence of a causal relationship between EBV antibody levels and AIDs through MR analysis. Our findings lay a new foundation and perspective for future research directions, clinical prognosis, and treatment.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and first identified in Wuhan, China, in December 2019, has led to global efforts in vaccination to mitigate rising morbidity and mortality, with vaccines proving crucial in controlling the pandemic. This study evaluated the humoral responses to the inactivated virus vaccine Sinopharm or Koxing Kerlafor, the protein subunit vaccine ZF001, and the adenoviral vector vaccine Convidecia after 18 months of inactivated virus vaccination by heterologous and homologous booster vaccination in patients with previous SARS-CoV-2 infection and healthy individuals. We discovered that patients who had recovered from the infection and then received a third vaccine dose (booster) exhibited durable immunity. Furthermore, the heterologous booster vaccine induced higher neutralizing antibody responses compared with the homologous booster. These findings offer valuable insights into the efficacy of different COVID-19 vaccine strategies following booster immunization.