Collagen is a survival factor against lipopolysaccharide-induced
apoptosis in cultured sheep pulmonary artery endothelial cells.
Hoyt, Dale G., Robert J. Mannix, James M. Rusnak, Bruce R. Pitt, and
John S. Lazo.
Department of Pharmacology, University of Pittsburgh School of
Medicine, Pittsburgh, PA 15261
APStracts 2:0044L, 1995.
Hoyt, Dale G., Robert J. Mannix, James M. Rusnak, Bruce R. Pitt and
John S. Lazo. Collagen is a Survival Factor Against
Lipopolysaccharide-Induced Apoptosis in Cultured Sheep Pulmonary
Artery Endothelial Cells. Am. J. Physiol. xxx (Lung Cell. Mol.
Physiol. xx): Lxxx-Lxxx, 199x). Lipopolysaccharide (LPS) causes
direct pulmonary endothelial injury that can precipitate cell death.
We investigated the ability of LPS to produce apoptosis in sheep
pulmonary artery endothelial cells (SPAEC) grown in monolayer on
plastic or collagen. When SPAEC were grown on plastic, LPS (100
ng/ml) caused internucleosomal DNA fragmentation (IDF) to 180-200
base pair ladders after 4 h. Higher order chromatin damage, producing
50 kilobase DNA fragments, occurred within 2 h. Significant DNA
strand breaks were seen in attached cells within 1 h incubation with
> 1 ng LPS/ml using in situ labelling by break extension (ISBE).
DNA strand breakage in attached cells peaked after 2 h and remained
elevated after 4 h. Detachment of SPAEC from the monolayer did not
begin until 4 h. SPAEC cultured on collagen were protected from LPS
-induced apoptosis; DNA damage measured by IDF, high molecular weight
DNA fragmentation and ISBE were suppressed. The protective effect of
collagen was not due to inactivation of LPS. Thus, LPS-induced
apoptosis occurs in SPAEC after genotoxic damage and this process is
suppressed by the extracellular matrix.
Received 13 December 1994; accepted in final form 23 March 1995.
APS Manuscript Number L353-4.
Article publication pending Am. J. Physiol. (Lung Cell. Mol.
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 4 April 1995.