Viruses-Basel最新文献

We previously reported on HIV vaccines that elicited autologous Tier 2 neutralizing antibodies (nAbs) in rabbits. In the current study, we sought to establish a proof of concept that HIV vaccines using identical designs elicit Tier 2 nAbs in arhesus macaque (RM) model. DNA and MVA vaccines expressing SIV Gag and HIV-1 Env antigens were constructed, and in vitro expression was confirmed. A soluble envelope protein (gp140 Env) was expressed from a stable HEK293 cell line and purified using lectin affinity and size exclusion chromatography. The expression and secretion of SIV Gag and HIV-1 Env by the DNA and MVA vaccines was verified in vitro. Five RMs were inoculated with two DNA, followed by two MVA, and finally with two gp140 Env vaccines at weeks 0, 4, 8, 12, 20 and 28. Vaccine-induced T cell immunity was measured by IFN-γ ELISpot while nAbs were evaluated against MW965 (Tier 1A), 6644 (Tier 1B), autologous ZM109.5A and a closely-related ZM109.B4 (Tier 2) pseudovirions. Vaccinated RMs were challenged intrarectally with simian-human immunodeficiency virus (SHIV), four weeks after the final vaccination, as was an unvaccinated control group (n = 4). Following vaccination, all the animals developed moderate IFN-γ ELISpot responses after the DNA vaccinations which were boosted by the MVA vaccine. After the gp140 Env boost, all animals developed nAbs with peak median titres at 762 (MW965) and 263 (ZM109.5A). The vaccinated animals became infected after a similar number of challenges to the unvaccinated controls, and the resultant number of viral copies in the blood and the lymphoid tissues were similar. However, the duration of detectable viraemia in the vaccinated animals (median: 2 weeks) was shorter than the controls (median: 8.5 weeks). These data show that the vaccines elicited robust cellular and functional humoral immune responses that resulted in a quicker control of viraemia.

Bacterial lipopolysaccharides (LPS) have been shown to promote enteric viral infections. This study assessed whether possessing elevated levels of LPS was associated with norovirus infection. Fecal samples from diarrheic norovirus-positive (DNP) (n = 26), non-diarrheal norovirus-negative (NDNN) (n = 26), asymptomatic norovirus-positive (ANP) (n = 15), and diarrheic norovirus-negative (DNN) (n =15) infants were assayed for selected bacterial LPS by quantitative PCR. The mean levels of selected LPS gene targets were significantly high in DNP infants (6.17 ± 2.14 CFU/g) versus NDNN infants (4.13 ± 2.25 CFU/g), p = 0.003. So too was the abundance between DNP and DNN infants (p = 0.0023). The levels of selected LPS gene targets were high regardless of whether the infection was symptomatic or asymptomatic, p = 0.3808. The average expression of genes coding for selected LPS and their signalling molecule, Toll-like receptor 4 (TLR4), increased 7- and 2.5-fold, respectively, in DNP versus NDNN children. Infants possessing elevated levels of selected LPS-rich bacteria were 1.51 times more likely to develop norovirus diarrhea (95% CI: 1.14-2.01, p = 0.004). In conclusion, norovirus infection was associated with abundance of selected bacterial LPS, suggesting a possible role of bacterial LPS in norovirus infection.

A novel double-stranded RNA (dsRNA) virus was isolated and described from strain ZZZ210557 of plant endophyte Allocryptovalsa sichuanensis. The dsRNA virus contains four dsRNA segments, dsRNA1 to dsRNA4, with a size range of 3.8 to 5.1 kbp. Each possesses a single large ORF and is encapsulated in isometric particles approximately 42-47 nm in diameter. Notably, the dsRNA3 encoded sequence revealed modest similarities to the amino acid sequences of RdRps predicted from the nucleotide sequences of known and suspected members of the family Quadriviridae. Phylogenetic analysis of the putative RdRp with the corresponding proteins of other quadriviruses revealed that the dsRNA virus is a new member belonging to the family Quadriviridae, tentatively named Allocryptovalsa sichuanensis quadrivirus 1 (AsQV1). All four segments of AsQV1 could be successfully cured through ribavirin treatment, whereas it likely has no apparent impact on the morphologies or virulence of the host fungus. This study is the first report of a quadrivirus isolated from the fungus A. sichuanensis, and our results enhance the diversity of the quadrivirus.

Lentiviral vector-transduced T cells were approved by the FDA as gene therapy anti-cancer medications. Little is known about the effects of host genetic variation on the safety and efficacy of the lentiviral vector gene delivery system. To narrow this knowledge gap, we characterized hepatic gene delivery by lentiviral vectors across the Collaborative Cross (CC) mouse genetic reference population. For 24 weeks, we periodically measured hepatic luciferase expression from lentiviral vectors in 41 CC mouse strains. Hepatic and splenic vector copy numbers were determined. We report that the CC mouse strains showed highly diverse outcomes following lentiviral gene delivery. For the first time, a moderate correlation between mouse-strain-specific sleeping patterns and transduction efficiency was observed. We associated two quantitative trait loci (QTLs) with intrastrain variations in transduction phenotypes, which mechanistically relates to the phenomenon of metastable epialleles. An additional QTL was associated with the kinetics of hepatic transgene expression. Genes found in the above QTLs are potential targets for personalized gene therapy protocols. Importantly, we identified two mouse strains that open new directions for characterizing continuous viral vector silencing and HIV latency. Our findings suggest that wide-range patient-specific outcomes of viral vector-based gene therapy should be expected. Thus, novel clinical protocols should be considered for non-fatal diseases.

Liver transplant recipients (LTRs) have been considered a population group that is vulnerable to COVID-19 as they are chronically immunosuppressed patients with frequent comorbidities. This study describes the course of the SARS-CoV-2 disease from February 2020 to December 2023 along seven pandemic "waves". We carried out an observational study on 307 COVID-19 cases in a cohort of LTRs with the aim of evaluating the changes in the disease characteristics over time and determining the risk factors for severe COVID-19. An older age and serum creatinine level ≥ 2 mg/dL were found to be risk factors for hospital admission and respiratory failure. The use of calcineurin inhibitors was a protective factor for death, hospitalization, and respiratory failure from COVID-19. One hundred percent of patients who died (N = 12) were on mycophenolate mofetil, which was a determinant for respiratory failure. Azathioprine was associated with admission to the intensive care unit (ICU) and with invasive mechanical ventilation (IMV). Vaccination was a protective factor for hospitalization, respiratory failure, and mortality. The severe COVID-19 rate was higher during the first five waves, with a peak of 57.14%, and the highest mortality rate (21.43%) occurred in the fourth wave. The IMV and ICU admission rates did not show significant differences across the periods studied.

Patients with hematological malignancies (HMs) are at higher risk of severe COVID-19 and secondary infections, which further complicate their outcomes. This study evaluated the impact of secondary infections (SIs) on mortality in hospitalized HM patients with SARS-CoV-2 infection and identified risk factors associated with SIs. We included 217 patients with HMs and COVID-19 admitted to a tertiary hospital in Rome, from April 2020 to September 2022. SIs occurred in 44.2% of patients, with bloodstream infections (42.7%) and respiratory infections (30.5%) being most frequent; among the latter, COVID-19-associated pulmonary aspergillosis (CAPA) was observed in 41.4% of cases. Viral reactivations, predominantly CMV, occurred in 9.2% of patients. The overall mortality rate was 29%, with higher mortality observed in patients with SIs (47.4% vs. 14.7%, p < 0.01). Risk factors for SIs included severe COVID-19 (OR = 2.957, p < 0.05) and prolonged hospitalization (OR = 1.095, p < 0.001). Severe COVID-19 (OR = 8.229, p < 0.001), intensive care unit (ICU) admission (OR = 15.232, p < 0.001), chronic steroid therapy (OR = 2.803, p < 0.05), SIs (OR = 2.892, p < 0.05), and viral reactivation (OR = 6.269, p < 0.01) were independent predictors of mortality. SIs and viral reactivations are common in patients with HMs and SARS-CoV-2 infection and significantly increase mortality, highlighting the need for timely management and preventive strategies in this vulnerable population.

This study assessed the diagnostic performance of influenza-related symptoms and signs and their combinations, as well as differences in patient characteristics based on the type/subtype of influenza, in outpatients at a primary healthcare surveillance system. Our prospective analysis included cases aged ≥ 15 years from two influenza seasons (2022/23 and 2023/24) in Novi Sad, Serbia. Influenza cases were confirmed using polymerase chain reaction (PCR) testing. The mean age of participants with laboratory-confirmed influenza was significantly lower than that of those without influenza (p < 0.0001): 37.90 vs. 54.92 years in 2022/23, and 40.21 vs. 54.17 years in 2023/24. Among the examined symptoms and signs, the highest sensitivity in the 2022/23 season was demonstrated for fever (87.95%, CI: 78.96-94.07), while in the 2023/24 season it was cough (100.00%, CI: 88.06-100.00). In the 2022/23 season, the positive predictive values (PPVs) were highest for fever (34.93%), chills (31.95%), myalgia (30.30%), and malaise (28.57%), but they dropped significantly in 2023/24 for all observed symptoms and signs (ranging from 1.91% to 9.17%). Compared to the World Health Organization's case definition for influenza-like illness (ILI), the case definition provided by the European Centre for Disease Prevention and Control demonstrated higher sensitivity but lower specificity across both seasons. Participants who tested positive between December and February were more likely to have influenza A(H1N1)pdm09 or A(H3N2), whereas those who tested positive between February and April were more likely to have influenza B. This study underscores the importance of seasonal timing, symptom evaluation, and case definitions in improving influenza diagnosis in primary care.

Hepatitis C virus (HCV) is a global public health problem, but advancements in HCV treatment have improved the cure rate. This study evaluated the effectiveness of direct-acting antivirals (DAAs) in HCV-infected patients from May 2021 to April 2023 in collaboration with tertiary care hospitals in West Bengal. The HCV viral load was monitored via qRT-PCR. Sanger sequencing was performed to determine the HCV genotypes. The clinicians prescribed the patient treatment regime. The maximum number of patients in the study population (N = 398) were compensated cirrhosis patients (46.28%). The overall SVR rate of the study population was 94.47%. The decompensated cirrhosis patients experienced the lowest SVR rate (88.89%). The maximum number of patients were prescribed sofosbuvir/daclatasvir (63.77%), and the lowest SVR rate (93.23%) was observed with this treatment regime. In the study population, GT-3 was the predominant (67.43%) circulating genotype, followed by GT-1 and -4. Among 398 patients, 22 (5.53%) were non-responsive to DAA treatment. Out of these 22 non-responder patients, 77.27% (n = 17) were GT-3-infected (3a:10; 3b:07), followed by GT-1 (1c: 04; 1b: 01). Thus, increasing numbers of DAA non-responsive cases among HCV GT-3-infected and decompensated cirrhosis patients may pose serious threats in the future.

Influenza poses a serious threat to both individual and public health. This study aimed to investigate the virological and epidemiological characteristics of influenza infections and to explore the genetic diversity of the circulating influenza viruses. In total, 1886 nasopharyngeal specimens from patients with acute respiratory illnesses were tested against 13 respiratory viruses using a multiplex real-time PCR. Whole-genome sequencing, phylogenetic, and amino acid analyses of representative influenza strains were performed. At least one respiratory virus was detected in 869 (46.1%) patients; 87 (4.6%) were co-infected with two or three viruses. Influenza A(H1N1)pdm09 was the most prevalent virus (16.1%), followed by rhinoviruses (8.1%) and RSV (6.7%). Hemagglutinin (HA) genes of the 74 influenza A(H1N1)pdm09 viruses were categorized in subclades C.1.8, C.1.9, and C.1 within clade 5a.2a and D1, D.2, and D.3 within clade 5a.2a.1. The A(H3N2) viruses analyzed belonged to clade 2a.3a.1, subclades J.2 and J.1. The sequenced B/Victoria lineage viruses fell into clade V1A.3a.2, subclades C.5.6 and C.5.7. Amino acid substitutions in most viral proteins were identified compared with the vaccine strains, including in the HA antigenic sites. This study demonstrated the dominant distribution of the influenza A(H1N1)pdm09 virus among the respiratory viruses studied and the genetic diversity of the circulating influenza viruses.

Carica papaya, a tropical fruit-bearing plant, has attracted significant attention for its diverse phytomedical properties and its ability to regulate both innate and adaptive immunity, making it a promising natural therapeutic agent. C. papaya is rich in bioactive compounds that play a multifaceted role in immunomodulation. These bioactive constituents have demonstrated efficacy not only against the dengue virus but also against other viral infections, including COVID-19 (Corona Virus Disease 2019), Human Immunodeficiency Virus (HIV), Zika virus, and others. The antiviral effects of C. papaya are achieved through its ability to enhance host immunity, mitigate inflammation, reduce oxidative stress, inhibit viral replication, and modulate immune responses. These mechanisms highlight its potential as a candidate for antiviral therapies, paving the way for further exploration of its pharmacological applications and promoting eco-friendly, accessible healthcare solutions for combating viral diseases. This review highlights the antiviral potential of C. papaya extracts in inhibiting viral replication and modulating immune responses, emphasizing the need for further studies and clinical trials to validate their efficacy against other medically significant viruses causing human diseases.