PMID: 9427712Jan 15, 1998Paper

Lipopolysaccharide activates caspase-1 (interleukin-1-converting enzyme) in cultured monocytic and endothelial cells.

Blood
R R SchumannD Pfeil

Abstract

Interleukin-1 beta (IL-1 beta) is a pleiotropic proinflammatory cytokine. Mechanisms leading to its secretion include not only release of newly synthesized protein, but also cleavage of a preformed immature precursor protein into an active secretory form by the intracellular protease caspase-1 (formerly termed IL-1-converting enzyme [ICE]). Caspase-1 belongs to a rapidly growing family of cysteine proteases with substrate specificity for aspartate involved in cellular apoptosis. We have used an assay determining the caspase-1 activity based on cleavage of a fluorogenic peptide substrate to elucidate its role in lipopolysaccharide (LPS)-induced secretion of IL-1 beta. We show that LPS induces moderate caspase-1 activity in the monocytic cell line THP-1, in freshly isolated peripheral blood monocytes, and in human umbilical vein endothelial cells (HUVECs) in a time- and dose-dependent fashion. Caspase-1 activation by LPS was associated with cleavage of the IL-1 beta precursor protein that was followed by release of the mature IL-1 beta protein in monocytic cells. In contrast, subsequent release of IL-1 beta by HUVECs was not significant. LPS-induced caspase-1 activation appeared not to result from modulation of caspase-1 transcri...Continue Reading

Related Concepts

Related Feeds

Apoptosis

Apoptosis is a specific process that leads to programmed cell death through the activation of an evolutionary conserved intracellular pathway leading to pathognomic cellular changes distinct from cellular necrosis

Related Papers

Expert Opinion on Biological Therapy
Mihai G NeteaLeo A B Joosten
DNA Sequence : the Journal of DNA Sequencing and Mapping
S WardlowL Nicolson
The Journal of Immunology : Official Journal of the American Association of Immunologists
R W WatsonG Watson
Journal of Interferon & Cytokine Research : the Official Journal of the International Society for Interferon and Cytokine Research
D W DavisA Holian
© 2021 Meta ULC. All rights reserved