Glucocorticoids sensitize the innate immune system through regulation of the NLRP3 inflammasome.

Busillo JM, Azzam KM, Cidlowski JA.
Source: J Biol Chem
Publication Date: (2011)
Issue: 286(44):: 38703-13
Research Area:
Immunotherapy / Hematology
Cells used in publication:
Species: human
Tissue Origin: blood
4D-Nucleofector® X-Unit
4D publication! For siRNA experiments, THP-1 cells were resuspended at 2  106 cells/ml in 4D NucleofectorTM X (Lonza) and mixed with 600 pmol of either non-targeting control or NLRP3 specific ONTARGETplus SMARTpool siRNAs (Dharmacon) and electroporated per the manufacturer’s instructions.
Glucocorticoids have long been recognized as powerful anti-inflammatory compounds that are one of the most widely prescribed classes of drugs in the world. However, their role in the regulation of innate immunity is not well understood. We sought to examine the effects of glucocorticoids on the NOD-like receptors (NLRs), a central component of the inflammasome and innate immunity. Surprisingly, we show that glucocorticoids induce both NLRP3 messenger RNA and protein, which is a critical component of the inflammasome. The glucocorticoid-dependent induction of NLRP3 sensitizes the cells to extracellular ATP and significantly enhances the ATP-mediated release of proinflammatory molecules, including mature IL-1?, TNF-?, and IL-6. This effect was specific for glucocorticoids and dependent on the glucocorticoid receptor. These studies demonstrate a novel role for glucocorticoids in sensitizing the initial inflammatory response by the innate immune system.