Importance of the field: Vaccines are still one of the best approaches to manage infectious diseases. Despite the advances in drug therapies, prophylactic medicine is still more cost efficient and minimizes the burden in the heath system. Despite all the research in vaccine development, many infectious diseases are still without an effective vaccine. The use of adjuvants in vaccines has been one successful strategy to increase efficacy. IFNs are widely expressed cytokines that have potent antiviral effects. These cytokines are the first line of defense against viral infections and have important roles in immuno surveillance for malignant cells. One of the most promising uses of IFNs is as adjuvants that are co-applied with antigen in vaccines.
Areas covered in this review: In this review, a cumulative analysis of many of the studies that have used IFN-α, -β, -γ and -λ as adjuvants between 1987 and the present suggests that many do possess the capacity to serve as potent immunoadjuvants for vaccination.
What the reader will gain: This review provides a very large collection of studies involving all types of IFNs used as adjuvants in vaccines using different vaccination strategies and various animal models.
Take home message: It is clear that the use of IFNs not only improved the efficacy and safety of most vaccines, but also had important immunomodulatory effect directing T(H)1 immune responses.