Type I & Type II Interferons (IFN’s)
The role they play in research
Interferons were originally described as agents that hinder viral replication, but have emerged over the years as critical mediators of cellular programming and defense against bacterial, protozoal and viral infections as well as tumors. IFNs have distinct roles in the immune response and are classified as Type I & Type II Interferons. Type I Interferon is a potent pro-inflammatory cytokine that can be released by a variety of immune cells after recognition of danger signals. The signaling of Type I IFNs activate the JAK/STAT cascade, impacting both innate and adaptive immune responses. Depending on the model, the presence of Type I IFNs can either prevent or enhance susceptibility to viral and microbial infections. IFN-y is the only Type II Interferon and is secreted primarily by NK cells, CD8+ T cells, and Th1 cells. IFN-y can directly limit viral replication, but has also been shown to be important in the immune response against protozoal and some bacterial infections, as well as cancer models. Specific inhibition of Type I & Type II interferons signaling may prove beneficial in developing novel therapeutics. The activity of Type I & II IFNs in the immune response continues to be an active area of research.