IFNA1, also known as IFN-alpha and IFNA, belongs to the alpha/beta interferon family. Interferons(IFNs) are proteins made and released by host cells in response to the presence of pathogens such as viruses, bacteria, parasites, or tumor cells. They belong to the large class of glycoproteins known as cytokines. IFNs stimulate the production of two enzymes: a protein kinase and an oligoadenylate synthetase. They allow for communication between cells to trigger the protective defenses of the immune system that eradicate pathogens or tumors. IFNs can activate immune cells, such as natural killer cells and macrophages; they increase recognition of infection or tumor cells by up-regulating antigen presentation to T lymphocytes, and they also increase the ability of uninfected host cells to resist new infection by the virus. Leukocyte interferon is produced predominantly by B lymphocytes. Immune interferon is produced by mitogen- or antigen-stimulated T lymphocytes. IFNA1 is produced by macrophages and has antiviral activities.