Adenovirus infections: new insights for the clinical laboratory.

Since their discovery in 1953, research on human adenoviruses (HAdVs) has had diverse foci, resulted in groundbreaking discoveries, such as gene splicing, and generated powerful oncolytic constructs and expression vectors for vaccine development and gene therapy. In contrast, virologists working in this field have made relatively little progress toward the prevention and treatment of the wide spectrum of HAdV-associated diseases. The understanding of species-specific features of viral pathogenesis, or of the mechanisms underlying the establishment of latency and reactivation, is still limited.

Approach for defining human adenovirus infection and disease for central review adjudication in clinical studies.

Background: Pediatric allogeneic hematopoietic cell transplant (allo-HCT) recipients are at risk for morbidity and mortality from human adenovirus (HAdV). HAdV can be detected in an asymptomatic state, referred to as infection or with signs or symptoms of illness, referred to as disease. Standardized case definitions are needed to distinguish infection from disease and allow for consistent reporting in both observational cohort studies and therapeutic clinical trials.

A Fulminant Case of Adenovirus Genotype C108 Infection in a Pediatric Stem Cell Transplant Recipient with x-Linked Lymphoproliferative Syndrome Type 1.

A 3-year-old male with X-linked lymphoproliferative syndrome type 1 underwent an unrelated umbilical cord blood transplant (UUCBT). The week prior to transplant the patient tested positive for adenovirus (HAdV) with a viral load of <190 copies/mL and was started on cidofovir. UUCBT proceeded as scheduled, and the patient engrafted on day +19.

Characterization of Human Adenoviruses of Medical Importance: Isolation of Infectious Virus from Clinical Specimens and Molecular Typing.

Human adenoviruses (HAdVs) constitute a group of ubiquitous viruses that currently comprises 51 well-defined serotypes and more than 113 genotypes classified into seven species, HAdV-A through HAdV-G. The members of these species differ considerably in their genomic characteristics and also in their tropism and pathogenicity. Virus isolation in cell culture remains critical for the preservation and comprehensive characterization of viruses of biomedical interest but has been almost completely abandoned by diagnostic laboratories.

Two novel recombinant human mastadenovirus D genotypes associated with acute respiratory illness.

Two novel genotypes of species human mastadenovirus D designated 109 and 110 were isolated from three epidemiologically unrelated cases of acute respiratory disease detected in January 2018 by surveillance efforts at the California/Mexico border. Both genotypes represent examples of intertypic recombination. Genotype D109 is most closely related to genotype D56 (97.

SARS-CoV-2 infection augments species- and age-specific predispositions in cotton rats.

Heterogeneity of COVID-19 manifestations in human population is vast, for reasons unknown. Cotton rats are a clinically relevant small animal model of human respiratory viral infections. Here, we demonstrate for the first time that SARS-CoV-2 infection in cotton rats affects multiple organs and systems, targeting species- and age-specific biological processes.

Intravenous delivery of GS-441524 is efficacious in the African green monkey model of SARS-CoV-2 infection.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the COVID-19 pandemic, has infected over 260 million people over the past 2 years. Remdesivir (RDV, VEKLURY®) is currently the only antiviral therapy fully approved by the FDA for the treatment of COVID-19. The parent nucleoside of RDV, GS-441524, exhibits antiviral activity against numerous respiratory viruses including SARS-CoV-2, although at reduced in vitro potency compared to RDV in most assays.

ICTV Virus Taxonomy Profile: 2022.

The family includes non-enveloped viruses with linear dsDNA genomes of 25-48 kb and medium-sized icosahedral capsids. Adenoviruses have been discovered in vertebrates from fish to humans. The family is divided into six genera, each of which is more common in certain animal groups.

Adenovirus: Epidemiology, Global Spread of Novel Types, and Approach to Treatment.

Adenoviruses (AdVs) are DNA viruses that typically cause mild infections involving the upper or lower respiratory tract, gastrointestinal tract, or conjunctiva. Rare manifestations of AdV infections include hemorrhagic cystitis, hepatitis, hemorrhagic colitis, pancreatitis, nephritis, or meningoencephalitis. AdV infections are more common in young children, due to lack of humoral immunity.

Oral Vaccination Protects Against Severe Acute Respiratory Syndrome Coronavirus 2 in a Syrian Hamster Challenge Model.

Background: Vaccines that are shelf stable and easy to administer are crucial to improve vaccine access and reduce severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmission around the world.

Methods: In this study, we demonstrate that an oral, adenovirus-based vaccine candidate protects against SARS-CoV-2 in a Syrian hamster challenge model.

Results: Hamsters administered 2 doses of VXA-CoV2-1 showed a reduction in weight loss and lung pathology and had completely eliminated infectious virus 5 days postchallenge.

Human Adenovirus Type 4 Comprises Two Major Phylogroups with Distinct Replicative Fitness and Virulence Phenotypes.

Human adenovirus type 4 (HAdV-E4) is the only type (and serotype) classified at present within species that has been isolated from a human host. Recent phylogenetic analysis of whole-genome sequences of strains representing the spectrum of intratypic genetic diversity described to date identified two major evolutionary lineages designated phylogroups (PGs) I and II and validated the early clustering of HAdV-E4 genomic variants into two major groups by low-resolution restriction fragment length polymorphism analysis. In this study, we expanded our original analysis of intra- and inter-PG genetic variability and used a panel of viruses representative of the spectrum of genetic diversity described for HAdV-E4 to examine the magnitude of inter- and intra-PG phenotypic diversity using an array of cell-based assays and a cotton rat model of HAdV respiratory infection.

Fatal Neonatal Sepsis Associated with Human Adenovirus Type 56 Infection: Genomic Analysis of Three Recent Cases Detected in the United States.

Background: Human adenovirus (HAdV)-D56 was first described in 2011 by genomics analysis of a strain isolated in France in 2008 from a fatal case of neonatal infection. Since then, it has been reported in cases of keratoconjunctivitis and male urethritis. Three epidemiologically unrelated fatal cases of neonatal sepsis associated with infection by HAdV-D strains with a similar genetic makeup were documented in the United States between 2014 and 2020.

Genotypes and phylogenetic analysis of adenovirus in children with respiratory infection in Buenos Aires, Argentina (2000-2018).

Human adenoviruses (HAdV) are one of the most frequent causes of respiratory infections around the world, causing mild to severe disease. In Argentina, many studies focused on the association of HAdV respiratory infection with severe disease and fatal outcomes leading to the discovery in 1984 of a genomic variant 7h associated with high fatality. Although several molecular studies reported the presence of at least 4 HAdV species (B, C, D and E) in Argentina, few sequences were available in the databases.

Human Adenovirus 7-Associated Hemophagocytic Lymphohistiocytosis-like Illness: Clinical and Virological Characteristics in a Cluster of Five Pediatric Cases.

Background: Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening condition of immune dysregulation. Children often suffer from primary genetic forms of HLH, which can be triggered by infection. Others suffer from secondary HLH as a complication of infection, malignancy, or rheumatologic disease.

Human Adenovirus Type 55 Distribution, Regional Persistence, and Genetic Variability.

Human adenovirus type 55 (HAdV-55) causes acute respiratory disease of variable severity and has become an emergent threat in both civilian and military populations. HAdV-55 infection is endemic to China and South Korea, but data from other regions and time periods are needed for comprehensive assessment of HAdV-55 prevalence from a global perspective. In this study, we subjected HAdV-55 isolates from various countries collected during 1969-2018 to whole-genome sequencing, genomic and proteomic comparison, and phylogenetic analyses.

Human mastadenovirus-B (HAdV-B)-specific E3-CR1β and E3-CR1γ glycoproteins interact with each other and localize at the plasma membrane of non-polarized airway epithelial cells.

The E3 region of all simian and human types classified within species Human mastadenovirus B (HAdV-B) encodes two unique highly conserved ORFs of unknown function designated E3-CR1β and E3-CR1γ. We generated a HAdV-3 mutant encoding small epitope tags at the N-termini of both E3-CR1β and E3-CR1γ (HAdV-3 N-tag wt) and a double knock out (HAdV-3 N-tag DKO) mutant virus that does not express either protein. Our studies show that HAdV-3 E3-CR1β and E3-CR1γ are type I transmembrane proteins that are produced predominantly at late times post infection, are glycosylated, co-localize at the plasma membrane of non-polarized epithelial cells, and interact with each other.

Isolation of a novel intertypic recombinant human mastadenovirus B2 from two unrelated bone marrow transplant recipients.

Human adenoviruses (HAdV) are well-known opportunistic pathogens of immunocompromised adult and pediatric patients but specific associations between HAdV species or individual HAdV types and disease are poorly understood. In this study we report the isolation of a novel HAdV-B2 genotype from two unrelated immunocompromised patients, both recipients of a hematopoietic cell transplant. In both patients, the course of HAdV infection is consistent with a scenario of reactivation of a latent virus rather than a primary opportunistic infection.

Genomic and phylogenetic analysis of two guinea pig adenovirus strains recovered from archival lung tissue.

Next generation sequencing was used to determine the whole genome sequence for two different strains of guinea pig adenovirus (GPAdV) detected in association with outbreaks of pneumonia in Australia in 1996, and in Germany in 1997 using total DNA extracted from infected archival frozen lung tissue as a template. The length of the determined genomic sequences was 37,031 bp and 37,070 bp, respectively. The nucleotide composition showed a relatively high content of guanine + cytosine (G + C) of 62 %.

Human Adenovirus 7d Strains Associated with Influenza-Like Illness, New York, USA, 2017-2019.

Human adenovirus 7d is a respiratory pathogen capable of causing acute respiratory disease of variable severity. Phylogenetic analysis of whole-genome sequences of 15 strains isolated from cases of influenza-like-illness during 2017-2019 demonstrated the circulation of 2 distinct clades of genomic variant 7d in colleges in New York, USA.

Isolation and initial propagation of guinea pig adenovirus (GPAdV) in cell lines.

 The lack of adequate systems to isolate and propagate guinea pig adenovirus (GPAdV), a prevalent cause of respiratory illness of varaible severity in laboratory guinea pig colonies worldwide, has precluded its formal characterization to allow for the development of comprehensive diagnostic assays, and for the execution of complex pathogenesis and basic virology studies. Two strains of GPAdV were isolated in guinea pig ( ) cell cultures from frozen archival infected animal tissue originated from colony outbreaks of pneumonia in Australia and the Czech Republic in 1996. Commercially available guinea pig cell lines from colorectal carcinoma (GPC-16), fetal fibroblast (104-C1) and lung fibroblast (JH4 C1), and the tracheal epithelial cell line GPTEC-T developed in this study were able to support viral infection and early propagation.

Genomic characterization of human adenovirus type 4 strains isolated worldwide since 1953 identifies two separable phylogroups evolving at different rates from their most recent common ancestor.

Species Human mastadenovirus E (HAdV-E) comprises several simian types and a single human type: HAdV-E4, a respiratory and ocular pathogen. RFLP analysis for the characterization of intratypic genetic variability has previously distinguished two HAdV-E4 clusters: prototype (p)-like and a-like. Our analysis of whole genome sequences confirmed two distinct lineages, which we refer to as phylogroups (PGs).