TODO
Interferons are a group of signaling proteins that are crucial in the body's defense against viral infections and in modulating the immune system. They are named for their ability to "interfere" with viral replication within host cells. Produced by immune cells like leukocytes, fibroblasts, and T cells in response to the presence of pathogens, interferons act as part of the first line of defense in the immune response.
There are three main types of interferons:
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Type I interferons: These include interferon-alphas and interferon-betas, and are primarily involved in antiviral defense. They help inhibit viral replication within infected cells, activate natural killer cells and macrophages, and increase the expression of major histocompatibility complex (MHC) molecules, enhancing the presentation of viral antigens to T cells.
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Type II interferons, also known as interferon-gammas, play a key role in both innate and adaptive immunity. It is essential for activating macrophages, enhancing antigen presentation, and promoting the differentiation of T helper cells, which are vital for a coordinated immune response. Interferon-gamma is also involved in controlling bacterial infections and has anti-tumor properties.
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Type III interferons, also known as interferon-lambdas, have functions similar to Type I interferons but are primarily involved in mucosal immunity, offering protection at epithelial surfaces such as the respiratory and gastrointestinal tracts.
Interferons have therapeutic applications, particularly in treating viral infections like hepatitis B and C, and certain cancers. They are also used in the management of multiple sclerosis due to their immunomodulatory effects. However, their use can be associated with side effects such as flu-like symptoms and fatigue.