Adenovirus Serotype Research Articles

Rapid Visual Detection Of Fowl Adenovirus Serotype 4 With Multienzyme Isothermal Rapid Amplification Combined with Lateral Flow Dipstick

Rapid Visual Detection Of Fowl Adenovirus Serotype 4 With Multienzyme Isothermal Rapid Amplification Combined with Lateral Flow Dipstick

An inactivated novel chimeric FAdV-4 containing fiber of FAdV-8b provides full protection against hepatitis-hydropericardium syndrome and inclusion body hepatitis

Fowl adenovirus serotype 4 (FAdV-4) and FAdV-8b are causative agents of hepatitis-hydropericardium syndrome (HHS) and inclusion body hepatitis (IBH), respectively. HHS and IBH co-infections were often reported in clinical, yet there are no commercially available bivalent vaccines for prevention and control of both FAdV-4 and -8b. In the present study, a chimeric FAdV-4 was firstly generated by substituting fiber-1 of FAdV-4 with fiber of FAdV-8b. The chimeric virus, rFAdV-4-fiber/8b, exhibited similar replication ability in vitro and pathogenicity in vivo to the parental wild type FAdV-4. A single dosage of vaccination with the inactivated rFAdV-4-fiber/8b induced high antibody titers against fiber-2 of FAdV-4 and fiber of FAdV-8b and provided full protection against FAdV-4 and -8b challenge. These results demonstrated that fiber of FAdV-8b could replace the role of fiber-1 of FAdV-4 in the process of viral infection, and rFAdV-4-fiber/8b could be used to make a potential bivalent vaccine for the control and prevention of HHS and IBH.

Hypervirulent FAdV-4 infection induces activation of the NLRP3 inflammasome in chicken macrophages

Fowl adenovirus serotype 4 (FAdV-4) is the primary causative agent of hepatitis–hydropericardium syndrome (HHS) causing great economic losses to the world poultry industry. The exact factors responsible for the pathogenesis of hypervirulent FAdV-4 have not been completely elucidated. Hypervirulent FAdV-4 infection induces inflammatory damages in accompany with a high level of proinflammatory interleukin-1 beta (IL-1β) secretion in a variety of organs. Investigation of the mechanisms underlying hypervirulent FAdV-4-induced IL-1β secretion would contribute to understanding of the pathogenesis of FAdV-4. Here, we investigated whether FAdV-4 infection activates NLRP3 inflammasome in chicken macrophage cell line HD11. The results showed that stimulation of HD11 with hypervirulent FAdV-4 induced NLRP3- and Caspase-1-dependent secretion of IL-1β. Genetic knockdown of NLRP3 or Caspase-1 expression, a critical component of inflammasome, significantly downregulated IL-1β expression, indicating that activation of the NLRP3 inflammasome contributed to the FAdV-4-induced IL-1β secretion. Moreover, ATP signaling and potassium efflux were involved in the process of NLRP3 inflammasome activation. Our data indicated that hypervirulent FAdV-4 infection induces the activation of NLRP3 inflammasome and followed by massive secretion of IL-1β of macrophages, which thereby contribute to the inflamed lesion of tissues.

Human Adenovirus Serotype 3 Infection Modulates the Biogenesis and Composition of Lung Cell-Derived Extracellular Vesicles.

Adenovirus (Ad) is a major causal agent of acute respiratory infections. However, they are a powerful delivery system for gene therapy and vaccines. Some Ad serotypes antagonize the immune system leading to meningitis, conjunctivitis, gastroenteritis, and/or acute hemorrhagic cystitis. Studies have shown that the release of small, membrane-derived extracellular vesicles (EVs) may offer a mechanism by which viruses can enter cells via receptor-independent entry and how they influence disease pathogenesis and/or host protection considering their existence in almost all bodily fluids. We proposed that Ad3 could alter EV biogenesis, composition, and trafficking and may stimulate various immune responses in vitro. In the present study, we evaluated the impact of in vitro infection with Ad3 vector on EV biogenesis and composition in the human adenocarcinoma lung epithelial cell line A549. Cells were infected in an exosome-free media at different multiplicity of infections (MOIs) and time points. The cell viability was determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and fluorometric calcein-AM. EVs were isolated via ultracentrifugation. Isolated EV proteins were quantified and evaluated via nanoparticle tracking, transmission electron microscopy, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and immunoblotting assays. The cell viability significantly decreased with an increase in MOI and incubation time. A significant increase in particle mean sizes, concentrations, and total EV protein content was detected at higher MOIs when compared to uninfected cells (control group). A549 cell-derived EVs revealed the presence of TSG101, tetraspanins CD9 and CD63, and heat shock proteins 70 and 100 with significantly elevated levels of Rab5, 7, and 35 at higher MOIs (300, 750, and 1500) when compared to the controls. Our findings suggested Ad3 could modulate EV biogenesis, composition, and trafficking which could impact infection pathogenesis and disease progression. This study might suggest EVs could be diagnostic and therapeutic advancement to Ad infections and other related viral infections. However, further investigation is warranted to explore the underlying mechanism(s).

Pathogenicity and virus shedding ability of fowl adenovirus serotype 4 to ducks

Fowl adenovirus serotype 4 (FAdV-4) is the pathogen causing hepatitis-hydropericardium syndrome (HHS) in broilers. Since June 2015, it has emerged as one of the leading causes of economic losses in the poultry industry in China. Although most studies on FAdV-4 have focused on its pathogenicity to broilers, limited studies have been performed on other natural hosts such as ducks and geese. In this study, we assessed the pathogenicity of FAdV-4 to ducks of different ages through intramuscular injection and found that infected ducks showed severe growth depression. The infected ducks also suffered from extensive organ damage and had histopathological changes in the liver, spleen, and kidney. Although the virus infection caused lymphocyte necrosis of immune organs and the development of the bursa of Fabricius (bursa) was inhibited, the humoral immune response of infected ducks to FAdV-4 remained strong. The infected ducks also had high viral load in tissues and shed virus after the challenge. Overall, our research demonstrates that FAdV-4 can infect ducks and adversely affect the productivity of animals. And the viruses shed by infected ducks can pose a potential risk to the same or other poultry flocks.

Immunity analysis against Fowl Adenovirus serotype 4 (FAdV-4) based on Fiber-2 trimer Protein with the different virulence

Since June 2015, Fowl adenovirus outbreaks have occurred in China, causing significant economic losses to poultry industry. The FAdV-4 Fiber-2 proteins could induce effective protection, but the precise mechanism of immune protection remains unknown. Here, we have compared the biological characteristics of Fiber-2 protein of the very virulent WZ strain of FAdV-4 (vvFAdV-4) with that of non-virulent ON1 strain. The sequence analysis revealed natural deletions and sequence differences between the classical non-pathogenic strain ON1 and the vvFAdV-4 isolate. These two Fiber-2 proteins successfully expressed in E. coli resemble in structure and function to the native-like trimeric protein. The trimeric structure and bioreactivity of the recombinant Fiber-2 proteins to FAdV-4 specific antibodies were characterized. The immune protection induced by Fiber-2 proteins of FAdV-4 WZ and ON1 strains were compared in SPF chickens. All birds in the WZ-Fiber-2 immunized group generated systemic specific antibodies compared with both ON1-Fiber-2 protein and PBS immunized groups. According to the results of attack mortalities, viral shedding and tissue gross lesion, the WZ Fiber-2 protein induced complete protection at a dose of 2 μg per chicken, whereas the ON1-Fiber-2 protein induced 0 protection at 3 dpc. In view of the characteristics of Fiber-2 proteins of different strains, this study can help us to further understand the mechanism of protective immunity and provide a basis for the prevention and control of FAdV-4 in chickens.

Disinfection efficacy and mechanism of olanexidine gluconate against norovirus

BackgroundThe purpose of this study was to evaluate the virucidal activity of a new olanexidine-containing formulation for hand hygiene (olanexidine gluconate hand rub; OLG-HR) against non-enveloped viruses and to understand its mechanism of action. MethodsThe virucidal activities of OLG-HR against two strains of caliciviruses and three adenovirus serotypes were evaluated through suspension tests. Also, virus-like particles were used to predict the effect of olanexidine gluconate on virus particle structure. ResultsThe results of suspension tests under conditions with and without interfering substances (1.5% BSA) indicated that OLG-HR had a broad-spectrum effect against non-enveloped viruses, and the virucidal effect was unaffected by organic contaminants. Furthermore, olanexidine inhibited the binding ability of virus-like particles to the binding receptor of human norovirus and increased the aggregation of virus-like particles in a dose-dependent manner. Transmission electron microscopy showed that the morphology of the virus-like particles was affected by exposure to olanexidine, indicating that the protein-denaturing effect of olanexidine gluconate caused the loss of receptor-binding capability of the viral capsid protein. ConclusionsThis study suggests that olanexidine gluconate is a potential biological and environmental disinfectant against norovirus and adenovirus.

Heterologous prime-boost immunizations with chimpanzee adenoviral vectors elicit potent and protective immunity against SARS-CoV-2 infection

A safe and effective vaccine for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is urgently needed to tackle the COVID-19 global pandemic. Here, we describe the development of chimpanzee adenovirus serotypes 6 and 68 (AdC6 and AdC68) vector-based vaccine candidates expressing the full-length transmembrane spike glycoprotein. We assessed the vaccine immunogenicity, protective efficacy, and immune cell profiles using single-cell RNA sequencing in mice. Mice were vaccinated via the intramuscular route with the two vaccine candidates using prime-only regimens or heterologous prime-boost regimens. Both chimpanzee adenovirus-based vaccines elicited strong and long-term antibody and T cell responses, balanced Th1/Th2 cell responses, robust germinal center responses, and provided effective protection against SARS-CoV-2 infection in mouse lungs. Strikingly, we found that heterologous prime-boost immunization induced higher titers of protective antibodies, and more spike-specific memory CD8+ T cells in mice. Potent neutralizing antibodies produced against the highly transmissible SARS-CoV-2 variants B.1.1.7 lineage (also known as N501Y.V1) and B.1.351 lineage (also known as N501Y.V2) were detectable in mouse sera over 6 months after prime immunization. Our results demonstrate that the heterologous prime-boost strategy with chimpanzee adenovirus-based vaccines is promising for further development to prevent SARS-CoV-2 infection.

The pros and cons of cytokines for fowl adenovirus serotype 4 infection.

Hepatitis-hydropericardium syndrome (HHS), caused by fowl adenovirus serotype 4 (FAdV-4), has spread on chicken farms worldwide, causing huge economic losses. Currently, the exact mechanism of pathogenesis of FAdV-4 remains unknown. Despite the severe inflammatory damage observed in chickens infected with pathogenic FAdV-4, few studies have focused on the host immune system-virus interactions and cytokine secretion. Host immunity acts as one of the most robust defense mechanisms against infection by pathogens, and cytokines are important in their elimination. However, excessive inflammatory cytokine secretion could contribute to the pathogenesis of FAdV-4. Understanding of the roles of cytokines produced during FAdV-4 infection is important for the study of pathogenicity and for developing strategies to control FAdV-4. Several previous studies have addressed the immune responses to FAdV-4 infection, but there has not been a systematic review of this work. The present review provides a detailed summary of the current findings on cytokine production induced by FAdV-4 infection to accelerate our understanding of FAdV-4 pathogenesis.

Identification of a novel immunological epitope on Hexon of fowl adenovirus serotype 4

Fowl adenovirus serotype 4 (FAdV-4), the causative agent of hepatitis-hydropericardium syndrome (HHS), distributed widely in the poultry farms in China. Hexon is one of the major capsid proteins associated with viral species or serotypes. However, the epitopes of Hexon protein remain largely unknown. In this study, a monoclonal antibody (mAb) specific to Hexon protein of FAdV-4, designated as 3G8, was generated. Subsequently, the linear peptide recognized by 3G8 was mapped and identified as 213AYGAYVK219 using a series of overlapping peptides generated from Hexon protein. Amino acid sequence analysis revealed that the epitope recognized by 3G8 was highly conserved across all the FAdVs. The epitope was immunogenic and could be recognized by FAdV-4 positive chicken serum samples. These findings will enrich our knowledge regarding the epitope on Hexon and provide valuable information for further characterization of the antigenicity of Hexon protein.

Ex Vivo and In Vivo CD46 Receptor Utilization by Species D Human Adenovirus Serotype 26 (HAdV26).

Human adenovirus serotype 26 (Ad26) is used as a gene-based vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and HIV-1. However, its primary receptor portfolio remains controversial, potentially including sialic acid, coxsackie and adenovirus receptor (CAR), integrins, and CD46. We and others have shown that Ad26 can use CD46, but these observations were questioned on the basis of the inability to cocrystallize Ad26 fiber with CD46. Recent work demonstrated that Ad26 binds CD46 with its hexon protein rather than its fiber. We examined the functional consequences of Ad26 for infection in vitro and in vivo. Ectopic expression of human CD46 on Chinese hamster ovary cells increased Ad26 infection significantly. Deletion of the complement control protein domain CCP1 or CCP2 or the serine-threonine-proline (STP) region of CD46 reduced infection. Comparing wild-type and sialic acid-deficient CHO cells, we show that the usage of CD46 is independent of its sialylation status. Ad26 transduction was increased in CD46 transgenic mice after intramuscular (i.m.) injection but not after intranasal (i.n.) administration. Ad26 transduction was 10-fold lower than Ad5 transduction after intratumoral (i.t.) injection of CD46-expressing tumors. Ad26 transduction of liver was 1,000-fold lower than that ofAd5 after intravenous (i.v.) injection. These data demonstrate the use of CD46 by Ad26 in certain situations but also show that the receptor has little consequence by other routes of administration. Finally, i.v. injection of high doses of Ad26 into CD46 mice induced release of liver enzymes into the bloodstream and reduced white blood cell counts but did not induce thrombocytopenia. This suggests that Ad26 virions do not induce direct clotting side effects seen during coronavirus disease 2019 (COVID-19) vaccination with this serotype of adenovirus. IMPORTANCE The human species D Ad26 is being investigated as a low-seroprevalence vector for oncolytic virotherapy and gene-based vaccination against HIV-1 and SARS-CoV-2. However, there is debate in the literature about its tropism and receptor utilization, which directly influence its efficiency for certain applications. This work was aimed at determining which receptor(s) this virus uses for infection and its role in virus biology, vaccine efficacy, and, importantly, vaccine safety.

Evaluation of intermolecular interactions required for thermostability of a recombinant adenovirus within a film matrix

Thermostability of vaccines and biologic drugs are key to increasing global access to a variety of life-saving agents. In this report, we characterize interactions between a novel zwitterionic surfactant and adenovirus serotype 5 which allow the virus to remain stable at room temperature in a thin film matrix. Complexity of the adenovirus capsid and the polydispersity of the surfactant required use of a variety of techniques to achieve this goal. The CMC of the surfactant in Tris buffer (pH 6.5) was estimated to be 0.7–1.17 × 10−4 M by the pyrene 1:3 ratio method. TEM images depict micelle formation around virus capsids. An estimated Kd of the virus-surfactant interaction of 2.25 × 10−9 M was determined by isothermal titration calorimetry. Associated data suggest that this interaction may be thermodynamically favorable and entropically driven. A competitive saturation study and TEM images indicate that the surfactant also binds to hexon proteins on the virus capsid. Taken together, these data support the working hypothesis that the surfactant is capable of forming micelles in the solid and liquid state and that it forms a protective coating around the virus by binding to hexon proteins on the virus capsid during the film forming process.

Historical Investigation of Fowl Adenovirus Outbreaks in South Korea from 2007 to 2021: A Comprehensive Review.

Fowl adenoviruses (FAdVs) have long been recognized as critical viral pathogens within the poultry industry, associated with severe economic implications worldwide. This specific group of viruses is responsible for a broad spectrum of diseases in birds, and an increasing occurrence of outbreaks was observed in the last ten years. Since their first discovery forty years ago in South Korea, twelve antigenically distinct serotypes of fowl adenoviruses have been described. This comprehensive review covers the history of fowl adenovirus outbreaks in South Korea and updates the current epidemiological landscape of serotype diversity and replacement as well as challenges in developing effective broadly protective vaccines. In addition, transitions in the prevalence of dominant fowl adenovirus serotypes from 2007 to 2021, alongside the history of intervention strategies, are brought into focus. Finally, future aspects are also discussed.

Fowl adenovirus serotype 4 uses gga-miR-181a-5p expression to facilitate viral replication via targeting of STING

Fowl adenovirus serotype 4 (FAdV-4) has caused substantial economic losses to the poultry industry and it has become a serious pathogen of poultry in China since 2015. MicroRNAs (miRNAs) play vital roles in regulating viral infection. However, how miRNAs regulate FAdV-4 replication in Leghorn male hepatocellular (LMH) cells remains unclear. This study aimed to elucidate the role of gga-miR-181a-5p in regulating FAdV-4 replication. The findings indicated that the expression of gga-miR-181a-5p was significantly upregulated in LMH cells during FAdV-4 infection. Also, the transfection of gga-miR-181a-5p mimics promoted FAdV-4 replication, while the opposite result was observed when gga-miR-181a-5p inhibitor was transfected in LMH cells. Moreover, the stimulator of interferon genes (STING) was found to be the target gene of gga-miR-181a-5p using software analysis, further confirming that STING was the target of gga-miR-181a-5p and gga-miR-181a-5p could negatively regulate the expression of STING at the mRNA and protein levels. Finally, the results showed that the overexpression of STING inhibited FAdV-4 replication and the knockout of STING promoted FAdV-4 replication. The collective findings revealed a novel host evasion mechanism adopted by FAdV-4 via gga-miR-181a-5p, suggesting novel strategies for designing miRNA-based vaccines and therapies.

Nanocomposites based on polylactide and silver nanoparticles and their antimicrobial and antiviral applications

Novel antimicrobial and antiviral silver-containing nanocomposites (PLA-Ag-PEI) based on polylactide (PLA) have been created by the thermochemical reduction of Ag+ ions in the polymer films. Structure-properties relationships of nanocomposites were investigated using FTIR, WAXS, TEM, DSC, TGA. It was found that thermochemical reduction of Ag+ ions in presence of polyethyleneimine as a reducing agent and stabilizer occurred above 100 °C for 5 min. The optimal parameters of the Ag+ ions reduction process in the polymer films were determined, i.e. 160°С for 5 min. The average size of Ag nanoparticles in the PLA-Ag-PEI was defined to be 6.7 nm. The nanocomposites have demonstrated strong antimicrobial activity against S. aureus and E. coli strains, as well as antiviral activity against herpes simplex virus type 1, influenza A virus and adenovirus serotype 2.

Characterization of Co-infection With Fowl Adenovirus Serotype 4 and 8a.

Fowl adenoviruses (FAdVs), which are distributed worldwide, have caused considerable economic losses to poultry farms. Co-infection with FAdVs and other avian pathogens has been reported previously. However, the pathogenicity of different serotypes of FAdVs causing co-infection remains unclear. Herein, strain HN from FAdV species C serotype 4 (FAdV-4) and strain AH720 from species E serotype 8a (FAdV-8a) were used to assess the pathogenicity of their co-infection in specific-pathogen-free (SPF) chickens. Compared with chickens infected with FAdV-4 alone, those co-infected with FAdV-4 and FAdV-8a showed similar clinical symptoms, mortality rates and degree of tissue lesions, and notably decreased viral loads of HN. Conversely, the viral loads of AH720 increased markedly in the co-infection group compared with that in chickens infected with AH720 strain alone. Increased viral loads of AH720 in the liver were suspected to contribute to the pathogenicity of chickens co-infected with the HN and AH720 strains. This was further investigated by histopathology and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining analyses. Collectively, these data indicated that co-infection with FAdV-4 and FAdV-8a suppresses the replication and proliferation of FAdV-4 but enhances the replication and proliferation of FAdV-8a in chicken liver. This study will provide valuable information for the further investigation of the interactions between FAdV-4 and FAdV-8a during co-infection.

Genetic diversity and molecular evolution of human adenovirus serotype 41 strains circulating in Beijing, China, during 2010-2019.

Human adenovirus serotype 41 (HAdV-F41) is an important pathogen that causes diarrhea in children. However, the data on its molecular genetic characteristics and evolutionary history are still neither comprehensive nor sufficient. Four capsid protein genes from 58 HAdV-F41-positive specimens taken from diarrheal children in Beijing during 2010-2019 were amplified and analyzed. Variant amino acids in the hexon gene (18 sites) and short fiber gene (4 sites) clustered these strains into two clades and four subclades. The deletion of 15 amino acids found in the gene seemed to have little effect on the genomic strain cluster same as to penton gene. The HAdV-F41 strains had high diversity, as assessed from the intraspecific recombination of hexon, short fiber and long fiber. The molecular evolutionary rate of HAdV-F41's concatenated genes was 4.07×10-5 substitutions/site/year, and it diverged from the most recent common ancestor in 1720. Apart from in the penton gene, positive selection codons were predicted in the other three genes, which may play a synergistic role in the evolution of HAdV-F41. These results provide new insights for understanding the characteristics of infectivity and developing vectors and vaccine vehicles for HAdV-F41.

Synthesis of New Modified with Rhodamine B Peptides for Antiviral Protection of Textile Materials.

Here we report on the synthesis and characterization of three new N-modified analogues of hemorphin-4 with rhodamine B. Modified with chloroacetyl, chloride cotton fabric has been dyed and color coordinates of the obtained textile materials were determined. Antiviral and virucidal activities of both the peptide-rhodamine B compounds and the dyed textile material were studied. Basic physicochemical properties (acid-base behavior, solvent influence, kinetics) related to the elucidation of structural activity of the new modified peptides based on their steric open/closed ring effect were studied. The obtained results lead to the conclusion that in protic solvent with change in pH of the environment, direct control over the dyeing of textiles can be achieved. Both the new hybrid peptide compounds and the modification of functionalized textile materials with these bioactive hemorphins showed virucidal activity against the human respiratory syncytial virus (HRSV-S2) and human adenovirus serotype 5 (HAdV-5) for different time intervals (30 and 60 min) and the most active compound was Rh-3.

Investigation of the antiviral activity of the recombinant human interferon lambda 1 in human conjunctiva cell culture

The aim of the study was to determine the efficacy of recombinant human interferon lambda 1 (IFN-λ1) against human adenovirus serotype 5 in a culture of human conjunctival cells Chang conjunctiva clone 1-5c-4. Material and methods. The study design consisted of three experimental schemes, reflecting a prophylactic and two options for a therapeutic and prophylactic treatment regimen (with the constant presence of the virus in the culture medium and with its removal after adsorption). The antiviral activity of IFN-λ1 was determined by the number of viable cells after exposure to the virus (MTT test). Results and discussion. It has been established that IFN-λ1 has antiviral activity against human adenovirus in vitro under a prophylactic and therapeutic-prophylactic scheme of administration at an infection dose of 1 and 10 TCID50 (50% tissue culture infectious dose), but not at an infection dose of 100 TCID50. The antiviral effect of the use of IFN-λ1 in a therapeutic and prophylactic regimen at an infection dose of 1 TCID50 was comparable to that of IFN-α. At the same time, both interferons did not have a toxic effect on the cell culture even at a concentration of 84 and 58 μg/ml, respectively. The antiviral activity and the absence of cytotoxic action provide the basis for further study of the possibility of development of based on IFN-λ1 drug for eye conjunctiva viral diseases treatment.

Fractionating a COVID-19 Ad5-vectored vaccine improves virus-specific immunity.

SARS-CoV-2 has caused a global pandemic that has infected more than 250 million people worldwide. Although several vaccine candidates have received emergency use authorization, there is still limited knowledge on how vaccine dosing affects immune responses. We performed mechanistic studies in mice to understand how the priming dose of an adenovirus-based SARS-CoV-2 vaccine affects long-term immunity to SARS-CoV-2. We first primed C57BL/6 mice with an adenovirus serotype 5 vaccine encoding the SARS-CoV-2 spike protein, similar to that used in the CanSino and Sputnik V vaccines. The vaccine prime was administered at either a standard dose or 1000-fold lower dose, followed by a boost with the standard dose 4 weeks later. Initially, the low dose prime induced lower immune responses relative to the standard dose prime. However, the low dose prime elicited immune responses that were qualitatively superior and, upon boosting, exhibited substantially more potent recall and functional capacity. We also report similar effects with a simian immunodeficiency virus (SIV) vaccine. These findings show an unexpected advantage of fractionating vaccine prime doses, warranting a reevaluation of vaccine trial protocols for SARS-CoV-2 and other pathogens.