Journal of Medical Virology最新文献

Background: High-dose Vitamin C (VitC) substantially boosts the anti-tumor effect of oncolytic adenoviruses (oAds), but optimizing its therapeutic potential remains to be fully explored. This study aims to investigate the synergistic effects of VitC and oAds on tumor cell viability and the underlying mechanisms. The CCK-8 assay and Flow cytometry were employed to detect the viability and apoptosis of tumor cells treated with VitC, oAds and VitC plus oAds. The combination therapy increased the oncolytic effect by 25-fold in CT26 cells and 10-fold in 4T1 cells, highlighting that VitC could enhance the oncolytic effect of oAds. Intermittent injection of VitC, rather than continuous injection, combined with oAds, was applied to examine the anti-tumor effect in vivo. Tumor-bearing mice receiving intermittent VitC alongside oAds showed smaller tumor volume, tumor weight and longer survival compared to those receiving the monotherapy. Additionally, no remarkable side effects were observed, as indicated by H&E staining of vital organs. Mechanistically, VitC synergized with oAds to recruit CD8⁺ effector T cells. These lymphocytes released IFN-γ, which reduced the expression of SLC7A11, a subunit of cystine/glutamate antiporter, and ultimately triggered ferroptosis by the reduced GSH. In conclusion, our findings propose a novel administration strategy for VitC that effectively augments the oncolytic effect of oAds, thereby warranting further investigation into its potential clinical applications.

Early detection of human papillomavirus type 16 (HPV16), the primary etiological agent of cervical cancer, is essential for effective clinical management. Specifically, detecting HPV16 E7 mRNA expression provides superior prognostic value, identifying transcriptionally active infections most likely to progress to precancerous lesions. In this study, we developed a fluorescence-based nanobiosensor that integrates catalytic hairpin assembly (CHA) with Fe₃O₄@Au core-shell nanoparticles (Fe₃O₄@Au NPs). This novel design combines magnetic enrichment and enzyme-free signal amplification, distinguishing it from prior HPV biosensors by enabling ultrasensitive detection in complex matrices like first-void urine (FVU). The biosensor showed linear fluorescence responses from 0.002 to 1 pM in PBS and 0.1-1 pM in FVU, with excellent specificity for single-base mismatch discrimination. It remained stable for 45 days. Validation using RNA from HPV16 plasmid-transformed E. coli and CaSki cells confirmed robust performance, while clinical swab specimens matched commercial assays completely. This biosensor offers a promising tool for early HPV16 detection in screening programs.

Non-hepatotropic viruses (NHVs), as a category of pathogens not primarily targeting the liver, can also cause hepatic injury. Liver injury associated with Epstein-Barr virus (EBV) and cytomegalovirus (CMV) infections, in particular, often attracts significant clinical attention. This retrospective cohort study analyzed the seroprevalence and clinical features of EBV and CMV infections among patients in Beijing from 2020 to 2024, with a focus on the impact of immunosuppression status on liver injury patterns. The CMV IgM positivity rate was 4.00% (646/16,201), and the EBV IgM positivity rate was 7.84% (1007/12,838), both showing significant upward annual trends (p < 0.001). Analysis of 236 IgM-positive inpatients revealed a "bifurcation phenomenon": the non-immunosuppressed group exhibited more severe hepatocellular injury (e.g., ALT levels 6.5- to 10.9-fold higher) and cholestatic damage (e.g., CMV group: TBIL increased 7.8-fold), yet had better clinical outcomes (adverse outcome rate: 0-4.8%) compared to the immunosuppressed group (adverse outcome rate: 18.4-27.8%, p < 0.05). Further analysis of 125 patients with confirmed liver injury demonstrated that the immunosuppressed group had severe CD4 + T-cell depletion and inverted CD4 + /CD8+ ratios. During EBV and CMV co-infection, the immunosuppressed group showed higher CMV DNA detection rates (66.7% vs. 20.0%, p = 0.0097) and viral loads (median 2675 vs. 625 copies/mL, p = 0.002). Within the immunosuppressed group, patients with CD4 + T-cell counts > 300 cells/μL had higher ALT and AST levels, supporting an immune-mediated injury mechanism. These findings indicate that immune status and virus type jointly shape the clinical spectrum of EBV/CMV-related liver injury. The dissociation between severe liver injury and favorable prognosis in non-immunosuppressed patients underscores the role of immune pathology, while poorer outcomes in immunosuppressed patients are driven by CD4 + T-cell depletion, impaired viral clearance, and extrahepatic complications.

Viral detection occurs frequently in critically ill patients. Patients with multiple viremic events had a higher ICU mortality. The highly sensitive mNGS technology has significantly enhanced viral pathogen detection rates. We enrolled 134 critically ill patients with severe infections who underwent mNGS testing during January 2019 to December 2021, at Qilu Hospital (Qingdao) of Shandong University. Viral pathogens were identified in 78 cases (58.2%). Torque teno virus (TTV) or herpesviruses (HVs) showed the highest detection rates (23.1% and 29.9%, respectively). The incidence of major adverse events (MAEs) in the hospital was 53.0%. Patients with TTV or HVs detection had more secondary nosocomial infections and stress ulcers, and the incidence of MAEs showed an increasing trend. Multivariate Logistic regression analysis showed that APACHE II score (OR: 1.10, 95%CI: 1.02-1.19, p = 0.018) and TTV or HVs detection by mNGS (OR: 2.40, 95% CI: 1.05-5.50, p = 0.038) were independent risk factors for MAEs. This study advocates the use of mNGS for detecting viruses in critically ill patients with severe infections, as it serves as a predictor for heightened risk of in-hospital MAE.

Torque teno virus (TTV) is a ubiquitous, nonenveloped DNA virus of the Anelloviridae family and a proposed surrogate marker of immune competence. Although nonpathogenic, its replication reflects host immune status and is associated with immune dysregulation during respiratory viral infections (RVIs). This study evaluated the interplay among TTV levels, inflammatory, endothelial, and coagulation biomarkers in acute RVIs. We collected 468 leftover material samples (234 respiratory and 234 blood samples) from hospitalized patients with PCR-confirmed RVIs. Patients were stratified by viral etiology, differential involvement of the respiratory tract, age, and possible co-detected pathogens. Cytokines (IL-6, IL-8, IL-1β, TNF-α), IFNs (α/β/γ), and endothelial markers (ICAM-1, VCAM-1) were quantified using microfluidic immunoassays. Routine coagulation parameters were measured in a subset of patients. TTV DNA load was quantified in both compartments using real-time PCR. Associations with inflammatory and coagulation parameters were assessed using nonparametric tests. TTV DNA was detectable across all age groups and viral etiologies, with higher levels in infants (0-1 years) and elderly patients (81-94 years). Blood and respiratory TTV levels were strongly correlated (r = 0.53, p < 0.0001). In infants, blood TTV correlated positively with IL-6 and CRP; in elderly patients, inverse correlations with TNF-α, IFN-α, and ICAM-1 suggested less regulated antiviral and endothelial responses. No significant differences were found by viral type or possible co-detected pathogens, though cytokine-TTV associations persisted. TTV levels reflect systemic and local immune activation during RVIs and deserve further investigation as possible noninvasive biomarker of immune dysregulation and thromboinflammatory risk. Longitudinal studies are needed to determine its prognostic value.

Viral load data provide critical insights into host-pathogen interactions and guide clinical and public health decisions. Because frequent testing is often infeasible, viral dynamics models are used to reconstruct infection trajectories, but optimal sampling strategies remain unclear. We compared two approaches for collecting SARS-CoV-2 viral load data: cross-sectional sampling (one measurement at symptom onset) and longitudinal sampling (every 3 days after onset) under constraints on the total number of tests and tests per individual. A viral dynamics model was first fitted to data from the National Basketball Association cohort, and the estimated parameters were treated as ground truth. Synthetic data were then generated under each sampling design, refitted, and evaluated for accuracy in estimating viral load over 30 days, peak viral load, peak time, and viral shedding duration. Longitudinal sampling consistently yielded lower root mean squared error and narrower one standard deviation interval than cross-sectional sampling. Peak timing and viral shedding duration were unbiased under both designs, but cross-sectional designs underestimated peak viral load and produced wider one standard deviation intervals. Coverage of viral load estimates was markedly higher for longitudinal designs (> 0.90) compared with cross-sectional ones (~0.10). Accuracy and coverage exceeded 0.96 even with just two tests per individual, with little additional benefit from more tests. In conclusion, longitudinal sampling—despite limited data—substantially improves accuracy and precision of viral load estimation compared with cross-sectional designs. These findings highlight efficient strategies for study design and resource allocation in infectious disease research.

Recently, cases of human infection with rat hepatitis E virus (ratHEV, Rocahepevirus ratti) have been reported worldwide. Due to the significant genetic differences between ratHEV and human HEV genotypes 1-4 (Paslahepevirus balayani), current HEV diagnostic assays are unable to detect ratHEV. The aim was to establish and validate a laboratory-developed ratHEV RT-qPCR assay for use with human plasma and stool samples on a fully automated, high-throughput platform. Published primers and probes were optimized for use on cobas 5800/6800/8800 systems using European Union In Vitro Diagnostics Regulation (IVDR)-grade reagents, including an RNA full-process inhibition control. Analytical sensitivity (21 repeats), linear range (five repeats) and precision (three repeats over 3 days) were evaluated using viral particles from cell culture (MN450851.1). The inclusivity was verified using DNA oligonucleotides and known positive samples (rat liver and human serum). The limits of detection were 98.9 copies/ml in plasma and 60.3 copies/ml in stool, and the assay showed excellent linearity over at least 5 log (r²: 0.991 in plasma and 0.9989 in stool) and high precision (< 0.62 ct). The assay reliably detected different ratHEV C1 subgenotypes, returning positive results for all 11 rat liver samples and one known ratHEV RNA-positive human plasma sample, while no false positives were detected in the broad cross-reactivity set (n = 41). In the pilot ratHEV surveillance cohort, 1.1% of plasma samples (n = 1999) were positive for HEV RNA, but none were positive for ratHEV RNA. Our new, fully automated, lab-developed ratHEV assay can be used in compliance with the IVDR for routine human diagnostics. Further studies are needed to determine the clinical relevance in different human cohorts.

Recombinant adeno-associated virus (rAAV) is a prominent vector for gene therapy; however, its transduction efficiency is hampered by intrinsic intracellular barriers. This study investigates the regulatory role of the lysosome-resident chloride/proton antiporter CLC-7 in rAAV trafficking and transduction. Using siRNA-mediated knockdown and pharmacological inhibition, we demonstrate that targeted disruption of CLC-7 function significantly enhances rAAV transduction efficiency in multiple in vitro cell models and in vivo murine model. Mechanistically, CLC-7 depletion alters lysosomal chloride homeostasis, leading to selective reduction in the catalytic activity of cathepsins B and L-key proteases involved in rAAV capsid processing -without impacting the activity of the Cl⁻-independent aspartic protease cathepsin D. Consequently, rAAV accumulates in lysosomes with delayed capsid degradation, with facilitates subsequent lysosomal escape of intact virions. Collectively, our findings identify CLC-7 as a critical negative regulator of rAAV transduction through modulation of lysosomal protease activity, providing a novel therapeutic target to optimize rAAV-based gene delivery strategies.

Background: Biliary atresia (BA) is a severe infantile hepatobiliary disorder of unknown etiology. Perinatal rotavirus (RV) infection has been implicated in animal models of BA; however, supporting human data remains limited. The study investigated the serological evidence of recent RV infection in infants with BA using RV-specific immunoglobulin (Ig)-A, a marker of primary infection unaffected by maternal antibodies.

Methods: Serum samples from 17 infants with BA and 30 age-matched controls without gastrointestinal symptoms or prior RV vaccination were retrospectively analyzed. Anti-RV-IgA titers were measured by enzyme-linked immunosorbent assay using purified WA-strain virions. Cytomegalovirus (CMV)-IgM and Epstein-Barr virus (EBV)-viral capsid antigen (VCA)-IgM levels were assessed using commercial enzyme immunoassays.

Results: RV-IgA was detected in 70.6% (12/17) of the patients with BA versus 3.4% (1/29) of the controls (p < 0.001). RV-IgA titers were significantly higher in the BA group (median: interquartile range 2^8.0:2^6.0-2^10.0) than in the control group (2^3.5:2^2.0-2^4.8) (p = 0.004). Among patients diagnosed with BA after 14 days of age, 84.6% (11/13) were RV-IgA-positive. CMV-IgM was detected in three patients in the BA group and one individual in the control group, while EBV-VCA-IgM was negative in BA patients and positive in two controls; neither difference was statistically significant.

Conclusions: The study findings support the potential association between RV infection and BA pathogenesis. However, the lack of an epidemiological reduction in BA following the introduction of the RV vaccine warrants caution in other studies. Further prospective multicenter studies are required to elucidate the causal role of RV infection in BA development.