Confounding role of tumor necrosis factor in cryopyrin-associated periodic syndromes.

The NLRP3 inflammasome is a critical component of the innate immune system and can be activated in response to microbial and endogenous danger signals. Activation of the NLRP3 inflammasome results in caspase-1-dependent secretion of the proinflammatory cytokines IL-1β and IL-18. Gain-of-function missense mutations in NLRP3 result in a group of autoinflammatory diseases collectively known as the cryopyrin-associated periodic syndromes (CAPS). CAPS patients have traditionally been successfully treated with therapeutics targeting the IL-1 pathway; however, there are a number of identified CAPS patients who show only a partial response to IL-1 blockade. In this issue of the JCI, McGeough et al. demonstrated that TNF-α, in addition to IL-1β, plays an important role in promoting NLRP3 inflammasomopathies.