Overview of the biology of type I interferons.

Type I interferons are pleiotropic cytokines with antiviral, antitumor and immunoregulatory functions. An aspect of their complex biology is the paradox that, depending on context, type I interferons can be anti-inflammatory and tissue protective or can be proinflammatory and promote autoimmunity. Along these lines, the activation of type I interferon pathways is effective in suppressing disease activity in patients with multiple sclerosis and in animal models of arthritis and colitis, while there is an expectation that blockade of the same pathways will be beneficial in the treatment of patients with systemic lupus erythematosus.