Immunology in clinic review series; focus on autoinflammatory diseases: role of inflammasomes in autoinflammatory syndromes

Autoinflammatory syndromes are disorders characterized by the hyperactivation of the innate immune system in the absence of microbial infection or autoantibody production. Some autoinflammatory syndromes are associated with recurrent episodes of fever and systemic inflammation that are caused by dysregulated activation of inflammasomes, molecular platforms responsible for the activation of caspase-1 and the production of interleukin (IL)-1 beta. In this review we will discuss the role of IL-1 beta and the inflammasomes in host defence and how mutations of two genes, NLRP3 and PYRIN, leads to the autoinflammatory syndromes, cryopyrin-associated periodic syndromes (CAPS) and familial Mediterranean fever (FMF). Both CAPS and FMF are characterized by increased inflammasome activity and overproduction of IL-1 beta which is ultimately responsible for disease manifestations. Importantly, understanding the molecular mechanisms of these syndromes has led to effective treatment for these rare diseases with biological drugs that target IL-1 beta-mediated signalling.