Some Adenovirus

Introduction

Adenovirus is a double-stranded DNA virus with >50 serotypes that infect human tissues, some of which show tropism for gastrointestinal mucosae. Adenovirus has been recognized as one of the important pathogens responsible for diarrhea. The virus is a spherical and non-enveloped particle with a diameter of 70-90 nm. The virion is composed of a protein capsid, made up of 252 capsomeres, and a nucleoprotein core that contains the DNA viral genome (26-46 kb long, containing 23-46 protein-coding genes) and internal proteins.

Fig1 Structure of adenovirus. (Waye, 2010)

Adenoviridae Family

Adenoviruses belong to the family Adenoviridae. To date, five genera of the Adenoviridae family have been classified including Mastadenovirus, Aviadenovirus, Atadenovirus, Siadenovirus, and Ichtadenovirus. The Mastadenovirus infects mammalian species whereas the Aviadenovirus infects avian species. The Atadenovirus and Siadenovirus infect a wide range of hosts while the Ichtadenovirus, which comprises only one member, infects fish (white sturgeon adenovirus 1). Human adenovirus is classified into 9 subgroups (A to I) and within each subgroup 90 genotypes have been identified. All subgroups of adenovirus infect the respiratory tract while subgroup F of serotypes 40 and 41 infect the gastrointestinal tract.

Pathogenesis

Human adenovirus can infect and replicate in epithelial cells of the gastrointestinal tract. The viruses cause lytic infection in epithelial cells and/or latent infection in lymphoid cells. The virus can actively replicate and inhibit the macromolecular synthesis and transport mRNA to the cytoplasm of the cell, facilitating cellular death and cell lysis. In addition, virions are produced, resulting in a host inflammatory response. Human adenovirus can persist in susceptible cells in a latent state for years and eventually re-activate, re-infect, and replicate in epithelial cells, causing disease symptoms again.

Fig2 Adenovirus infection and replication pathway. (Waye, 2010)

Epidemiology

Adenoviruses typically cause self-limited respiratory, gastrointestinal, or conjunctival disease throughout the year, without significant seasonal variation. Adenovirus can be transmitted by inhalation, direct contact with small droplets, or the fecal-oral route. It has been reported that adenovirus is a causative agent of several outbreaks in communities such as schools, nurseries, and military camps, the virus being able to contaminate environmental sources including food and water. The incubation period depends on the virus serotype and mechanism of transmission and can range from 2 days to 2 weeks. Most of these occur in children younger than the age of 5 years and are generally self-limiting illnesses. Acute infection is usually self-limited in immunocompetent adults, but the virus may establish asymptomatic persistent infection.

Symptoms

Illnesses are usually mild. Patients often present with watery diarrhea lasting 5-12 days, vomiting, cramps. Adenovirus can cause lymphoid hyperplasia leading to obstruction or intussusception particularly in the pediatric population. In addition, the adenovirus infection can cause symptoms such as eye diseases and respiratory diseases. Severe adenovirus infection with a high mortality rate can affect infants, immunocompromised patients, or transplant recipients. Immunosuppressed individuals may develop nephritis, enteritis, hepatitis, pneumonia, and encephalitis, any of which may be fatal.

Prevention and Treatment

• Prevention: Currently no adenovirus vaccine is available to the general public. A live, oral vaccine against types 4 and 7 was used by the U.S. military.
• Treatment: There is no specific treatment for people with adenovirus infection. Most adenovirus infections are mild and may require only care to help relieve symptoms. The treatment is focused on managing patient symptoms and avoiding the appearance of complications.

Antibody Products and Services

Creative Biolabs has become the partner of choice to provide various ViroAntibody products (e.g. primary antibodies, secondary antibodies, pseudovirus) to advance your virology research goals. We provide a variety of monoclonal and polyclonal antibodies against Adenovirus for wide applications. Our experts understand the virology researches to provide personalized solutions, including ViroAntibody Neutralization Assays, ViroAntibody Discovery Services, ViroAntibody Engineering Services, ViroAntibody Customized Services. If you are interested in our antibody products or services, please feel free to contact us for more details.

Reference

1. Waye, Mmy.; Sing C.W. Anti-Viral Drugs for Human Adenoviruses. Pharmaceuticals. 2010, 3(10): 3343-3354.

All products and services are intended for Research Use Only, and NOT to be used in diagnostic or therapeutic procedures.