Understanding the mechanism of IL-1β secretion

The cytokine interleukin-1 beta (IL-1 beta) is a key mediator of the inflammatory response. Essential for the host-response and resistance to pathogens, it also exacerbates damage during chronic disease and acute tissue injury. It is not surprising therefore that there is a huge level of interest in how this protein is produced and exported from cells. However, the mechanism of 1L-1 beta release has proven to be elusive. It does not follow the conventional ER-Golgi route of secretion. A literature full of disparate observations arising from numerous experimental systems, has contributed to a complicated mix of diverse proposals. Here we summarise these observations and propose that secretion of 1L-1 beta occurs on a continuum, dependent upon stimulus strength and the extracellular IL-1 beta requirement. (C) 2011 Elsevier Ltd. All rights reserved.