Format

Send to

Choose Destination
J Biol Chem. 2006 Jul 21;281(29):20055-67. Epub 2006 May 17.

Specific recognition of apoptotic cells reveals a ubiquitous and unconventional innate immunity.

Author information

1
Department of Microbiology and Immunology, Section of Nephrology, University of Illinois College of Medicine, Chicago, Illinois 60612, USA.

Abstract

The purpose of physiological cell death is the noninflammatory clearance of cells that have become inappropriate or nonfunctional. Consistent with this function, the recognition of apoptotic cells by professional phagocytes, including macrophages and dendritic cells, triggers a set of potent anti-inflammatory responses manifest on multiple levels. The immediate-early inhibition of proinflammatory cytokine gene transcription in the phagocyte is a proximate consequence of recognition of the apoptotic corpse, independent of subsequent engulfment and soluble factor involvement. Here, we show that recognition is linked to a characteristic signature of responses, including MAPK signaling events and the ablation of proinflammatory transcription and cytokine secretion. Specific recognition and response occurs without regard to the origin (species, tissue type, or suicidal stimulus) of the apoptotic cell and does not involve Toll-like receptor signaling. These features mark this as an innate immunity fundamentally distinct from the discrimination of "self" versus "other" considered to be the hallmark of conventional immunity. This profound unconventional innate immune discrimination of effete from live cells is as ubiquitous as apoptotic cell death itself, manifest by professional and nonprofessional phagocytes and nonphagocytic cell types alike. Innate apoptotic immunity provides an intrinsic anti-inflammatory circuit that attenuates proinflammatory responses dynamically and may act systemically as a powerful physiological regulator of immunity.

PMID:
16707494
DOI:
10.1074/jbc.M603920200
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for HighWire
Loading ...
Support Center