Adenovirus vaccine
An adenovirus vaccine is designed to stimulate an immune response against adenovirus infections, which can range from mild respiratory illnesses to severe complications in immunocompromised individuals. These vaccines can be categorized into different types: B cell vaccines, which help produce long-lasting antibodies; T cell vaccines, aimed at generating killer T cells to eliminate infected cells; and recombinant vaccines that enhance the immune response to other viral antigens. Historically, the U.S. military used a live oral B cell vaccine targeting adenovirus types 4 and 7, which significantly reduced respiratory diseases among recruits. This vaccine was discontinued in 2011 but was replaced with a new oral recombinant vaccine that continues to be available only to military personnel. T cell vaccines are still under clinical investigation, with the potential to offer broader protection, especially to those at risk of severe illness. The impact of these vaccines highlights their importance in preventing adenovirus-related health issues, particularly in specific populations. Overall, the development and study of adenovirus vaccines underscore their role in public health, particularly for vulnerable groups.
On this Page
Subject Terms
Adenovirus vaccine
Definition
An adenovirus vaccine is a nonpathogenic form of adenovirus or its antigens. It is given to animals, including humans, to stimulate the formation of a memory immune response to adenovirus infection.
B cell vaccine. Adenovirus B cell vaccines stimulate B cells to differentiate into long-lived plasma cells. Upon subsequent contact with adenovirus, these plasma cells secrete antibodies that specifically neutralize adenovirus.
From 1971 to 1996, the US military routinely administered to recruits an enteric-coated live oral vaccine against human adenovirus types 4 and 7, which frequently cause acute respiratory disease and pneumonia in that population. The vaccine induced a strong immune response because it presented B cells with strong antigens in their natural shape. Infection of epithelial cells in the small intestine allowed viral replication, but it was asymptomatic. The vaccine was unavailable to civilians because most adenovirus infections are mild and self-limiting.
T cell vaccine. Many people carry adenovirus without symptoms. Immunodeficiency, induced so that a person can receive a tissue or organ transplant, allows the virus to spread in the infected person and cause severe and potentially lethal disseminated infection. An adenovirus T cell vaccine gives those persons cytotoxic T cells (or killer T cells), which recognize and destroy cells infected by adenovirus or gives them helper T cells, which help cytotoxic T cells perform those functions. T cell vaccines remain under clinical study and are not available for use.
A vaccine can be prepared by selecting and growing donated helper T cells that naturally recognize adenovirus capsid hexon protein antigenic fragments. Alternatively, a vaccine can be prepared by using donated monocytes to train donated naïve cytotoxic T cells to recognize antigenic fragments of all adenovirus capsid proteins. The monocytes are modified by infection with recombinant adenovirus to produce the antigenic fragments, and they present the antigenic fragments to the cytotoxic T cells.
Recombinant vaccine. The antigens of many viruses (such as hepatitis C virus or human immunodeficiency virus) stimulate only weak production of antibodies by B cells. However, recombinant adenoviruses linking those antigens to the adenovirus capsid proteins can greatly increase the production of antibodies to the antigens.
Most people have been infected by adenovirus and have associated antibodies. Those antibodies weaken the vaccine by neutralizing the recombinant adenovirus. Attempts to overcome this problem include changing the adenovirus capsid hexon or fiber to a form less recognizable by the immune system and administering vaccines by a mucosal rather than an intramuscular or subcutaneous route.
Impact
The B cell vaccine previously used against human adenovirus types 4 and 7 decreased adenovirus respiratory disease in military recruits by 82 to 95 percent. The economic value of that health benefit is estimated to be worth $22 million annually. This vaccine was discontinued in 2011 and replaced with a new, live, oral vaccine, which is a recombinant vaccine also targeting types 4 and 7. It is given as two enteric-coated tablets. This vaccine is only available to military personnel.
Clinical trials suggest that T cell vaccines may decrease the significant risk of illness or death caused by severe disseminated adenovirus infection. Ongoing clinical trials will determine if these vaccines can be made available, as they are believed to provide broader protection.
Bibliography
"Adenovirus Vaccine Information Statement." CDC, 8 Jan. 2020, www.cdc.gov/vaccines/hcp/vis/vis-statements/adenovirus.html. Accessed 2 Oct. 2024.
Chatziandreou, Ilenia, et al. "Capture and Generation of Adenovirus Specific T Cells for Adoptive Immunotherapy." British Journal of Haematology, vol. 132, 2006, pp. 117-126.
Foy, H. M. "Adenoviruses." Viral Infections in Humans: Epidemiology and Control, edited by A. Evans and R. Kaslow. 4th ed., New York: Plenum, 1997.
Grandi, Guido, editor. Genomics, Proteomics, and Vaccines. Hoboken, N.J.: John Wiley & Sons, 2004.
Heymann, David L., editor. Control of Communicable Diseases Manual. 19th ed., Washington, D.C.: American Public Health Association, 2008.
Horwitz, M. S. "Adenoviruses." Fields’ Virology, edited by David M. Knipe and Peter M. Howley. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins, 2007.
Plotkin, Stanley A., and Walter A. Orenstein, editors. Vaccines. 5th ed., Philadelphia: Saunders/Elsevier, 2008.
Russell, Kevin L., et al. "Vaccine-Preventable Adenoviral Respiratory Illness in U.S. Military Recruits, 1999-2004." Vaccine, vol. 24, 2006, pp. 2835-2842.
Sinha, Sanchari. "What are Adenovirus-Based Vaccines?" News-Medical, 10 Mar. 2021, www.news-medical.net/health/What-are-Adenovirus-Based-Vaccines.aspx. Accessed 2 Oct. 2024.
Stern, Alexandra Minna, and Howard Markel. "The History Of Vaccines and Immunization: Familiar Patterns, New Challenges." Health Affairs, vol. 24, no. 3, 2005, pp. 611-621.