Phosphocholine reverses inhibition of pulmonary surfactant
adsorption caused by c-reactive protein .
McEachren, Todd M., and Kevin M. W. Keough.
Department of Biochemistry and Discipline of Pediatrics, Memorial
University of Newfoundland, St. John's, Newfoundland Canada, A1B
3X9
APStracts 2:0083L, 1995.
The influence of the acute inflammatory phase protein human C-reactive
protein (CRP) on the adsorption of porcine pulmonary surfactant from
a subphase into an air-water interface has been investigated. CRP was
shown to detract from the ability of surfactant to rapidly adsorb to
the air-water interface at a molar ratio of 0.03 : 1, protein to
phospholipid (weight ratio, 0.5 : 1). On a weight basis, CRP was
found to be more effective than fibrinogen at reducing the adsorption
rate of surfactant. The effect of CRP required the presence of
calcium, and was reversed by the addition of phosphocholine, in a
concentration dependent manner. The inhibition of surfactant
adsorption by CRP was effectively eliminated by the addition of
phosphocholine at a molar ratio of 300 : 1, phosphocholine : CRP, but
it was not diminished by the addition of identical molar ratios of _
-phosphoethanolamine or DL-[alpha]-glycerophosphate at the same molar
ratios. These data suggest that the potent inhibition of surfactant
adsorption by CRP is primarily a result of a specific interaction
between CRP and the phosphocholine headgroup of surfactant lipids in
the subphase and that it can be reversed by the water-soluble CRP
ligand, phosphocholine.
Received 6 June 1994; accepted in final form 9 May 1995.
APS Manuscript Number L158-4.
Article publication pending Am. J. Physiol. (Lung Cell. Mol.
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 26 May 1995.