Hemagglutinin
Hemagglutinin is a type of protein found on the surface of influenza viruses. It plays a crucial role in the virus infection process by enabling the virus to bind to and enter host cells. Hemagglutinin is also a primary target for the immune response to influenza infection and is the main component of most influenza vaccines.
Structure and Function[edit | edit source]
Hemagglutinin is a glycoprotein that forms a trimeric complex on the surface of the influenza virus. Each monomer of the complex consists of a long, rod-like stem and a globular head. The head contains the binding site for sialic acid, a component of the receptors on the surface of host cells.
Upon binding to sialic acid, hemagglutinin undergoes a conformational change that allows the virus to fuse with the host cell membrane and release its genetic material into the cell. This process is essential for the virus to establish an infection.
Immune Response and Vaccination[edit | edit source]
The immune system recognizes hemagglutinin as a foreign substance and produces antibodies against it. These antibodies can neutralize the virus by blocking its ability to bind to host cells.
Most influenza vaccines are designed to stimulate an immune response against hemagglutinin. They typically contain purified hemagglutinin from several different strains of influenza virus, chosen based on predictions of which strains will be most prevalent in the upcoming flu season.
Variation and Antigenic Drift[edit | edit source]
Influenza viruses are classified based on the type of hemagglutinin they express. There are 18 known types of hemagglutinin, designated H1 through H18.
The hemagglutinin protein is subject to frequent mutation, a process known as antigenic drift. This allows the virus to evade the immune response and is one of the reasons why a new influenza vaccine must be formulated each year.
See Also[edit | edit source]
| Hemagglutinin Resources | |
|---|---|
|
 |
Search WikiMD
Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD
|
WikiMD's Wellness Encyclopedia |
| Let Food Be Thy Medicine Medicine Thy Food - Hippocrates |
Translate this page: - East Asian
中文,
日本,
한국어,
South Asian
हिन्दी,
தமிழ்,
తెలుగు,
Urdu,
ಕನ್ನಡ,
Southeast Asian
Indonesian,
Vietnamese,
Thai,
မြန်မာဘာသာ,
বাংলা
European
español,
Deutsch,
français,
Greek,
português do Brasil,
polski,
română,
русский,
Nederlands,
norsk,
svenska,
suomi,
Italian
Middle Eastern & African
عربى,
Turkish,
Persian,
Hebrew,
Afrikaans,
isiZulu,
Kiswahili,
Other
Bulgarian,
Hungarian,
Czech,
Swedish,
മലയാളം,
मराठी,
ਪੰਜਾਬੀ,
ગુજરાતી,
Portuguese,
Ukrainian
Medical Disclaimer: WikiMD is not a substitute for professional medical advice. The information on WikiMD is provided as an information resource only, may be incorrect, outdated or misleading, and is not to be used or relied on for any diagnostic or treatment purposes. Please consult your health care provider before making any healthcare decisions or for guidance about a specific medical condition. WikiMD expressly disclaims responsibility, and shall have no liability, for any damages, loss, injury, or liability whatsoever suffered as a result of your reliance on the information contained in this site. By visiting this site you agree to the foregoing terms and conditions, which may from time to time be changed or supplemented by WikiMD. If you do not agree to the foregoing terms and conditions, you should not enter or use this site. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.
Contributors: Prab R. Tumpati, MD
