Alpha interferon is produced by white blood cells other than lymphocytes, beta interferon by fibroblasts, and gamma interferon by natural killer cells and cytotoxic T lymphocytes (killer T cells). All interferons inhibit viral replication by interfering with the transcription of viral nucleic acid.
What is the interferon pathway?
The interferon (IFN) pathway plays a critical role in the human immune response. One of the many responses to the viral invasion is the induction of the pleiotropic cytokines, interferon (IFN). Induction of IFN gene expression leads to increased cellular resistance to viral infection and may also affect cell growth.
What is the process of interferon production?
Interferons are formed when most cells are treated with viruses or double-stranded RNA (to form IFN-alpha or beta, or both) or when lymphoid cells are treated with mitogens or the appropriate antigen (to form IFN-gamma).
What is the type 1 interferon pathway?
All type I interferons (IFNs) bind a common receptor at the surface of human cells, which is known as the type I IFN receptor. The type I IFN receptor is composed of two subunits, IFNAR1 and IFNAR2, which are associated with the Janus activated kinases (JAKs) tyrosine kinase 2 (TYK2) and JAK1, respectively.
What secretes interferon alpha?
IFN-alpha 1 is secreted by immune (lymphocytes, NK cells, B-cells and T-cells, macrophages) and non-immune cells (fibroblasts, endothelial cells, osteoblasts and others) in answer to a viral infection.
How is interferon alpha administered?
This medication is given by injection into a muscle or under the skin as directed by your doctor. Rotate the injection site each time you inject this medication to prevent soreness. It may also be given by injection into a vein or directly into a lesion, usually by a health care professional.
What is the use of alpha interferon?
Alpha interferon is a cytokine produced by the innate immune system in response to environmental exposures including viral infections. Alpha interferon in various formulations has been developed as therapy of several forms of cancer and viral infections, but its major use has been as therapy of chronic hepatitis C.
How does interferon alpha work?
How interferon alfa works. Interferon alfa stimulates T cells and other immune system cells to attack the cancer. It can also encourage cancer cells to send out chemicals that attract immune system cells to them.
What is the mechanism of action of interferon?
Mechanism of Action: Interferons inhibit varying stages of viral replication including viral entry, uncoating, mRNA synthesis and protein synthesis. IFNs have profound immunomodulatory properties. The immune response to IFN-alpha appears to be critical to clearance of hepatitis B and C infection.
What are type 1 and type 2 interferons?
Expression of type I and III IFNs can be induced in virtually all cell types upon recognition of viral components, especially nucleic acids, by cytoplasmic and endosomal receptors, whereas type II interferon is induced by cytokines such as IL-12, and its expression is restricted to immune cells such as T cells and NK …
Which cell releases interferon alpha?
Type I interferon (IFN-alpha and IFN-beta) is secreted by virus-infected cells while type II, immune or gamma interferon (IFN-gamma) is mainly secreted by T cells, natural killer (NK) cells and macrophages.
When are alpha and beta interferons produced?
There are three types of interferons (IFN), alpha, beta and gamma. IFN-alpha is produced in the leukocytes infected with virus, while IFN-beta is from fibroblasts infected with virus. IFN-gamma is induced by the stimulation of sensitized lymphocytes with antigen or non-sensitized lymphocytes with mitogens.
What is the interferon signaling pathway?
Interferon (IFN) Cell Signaling Pathway. Following viral infection, the human body triggers a complex regulatory system of innate and adaptive immune responses designed to defend against the virus. One of the many responses to the viral invasion is the induction of the pleiotropic cytokines, interferon (IFN) [1].
What are Type I interferons composed of?
Type I interferons (IFNs) are composed of various genes including IFN alpha (IFNA), beta (IFNB), omega, epsilon, and kappa. In humans the IFNA genes are composed of more than 13 subfamily genes, whereas there is only one IFNB gene.
What is the role of interferon in viral infection?
Following viral infection, the human body triggers a complex regulatory system of innate and adaptive immune responses designed to defend against the virus. One of the many responses to the viral invasion is the induction of the pleiotropic cytokines, interferon (IFN) [1].
How do interferon JAKs work?
Interferon Pathway. The IFN-Gamma-activated JAKs also regulate, through as yet-unknown intermediates, activation of the catalytic subunit (p110) of PI3K. The activation of PI3K ultimately results in downstream activation of PKC-Delta (Protein Kinase-C-Delta), which in turn regulates phosphorylation of STAT1 on Ser727.
