Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2010-4-27
pubmed:abstractText
Chitosan is a polycationic and biocompatible polysaccharide composed of glucosamine and N-acetyl glucosamine that is chemotactic for neutrophils and stimulates wound repair through mechanisms that remain unclear. It was previously shown that chitosan depletes complement proteins from plasma, suggesting that chitosan activates complement. Complement activation leads to cleavage of C5 to produce C5a, a neutrophil chemotactic factor. Here, we tested the hypothesis that chitosan generates C5a in human whole blood, citrated plasma, and serum. C5a fragment appeared in coagulating whole blood, and mixtures of chitosan-glycerol phosphate/whole blood, in parallel with platelet and thrombin activation. However, in plasma and serum, thrombin and chitosan-GP failed to generate C5a, although native C3, C5, and factor B adsorbed noncovalently to insoluble chitosan particles incubated in citrated plasma, serum, EDTA-serum and methylamine-treated plasma. By surface plasmon resonance, pure C3 adsorbed to chitosan. The profile of serum factors associating with chitosan was consistent with a model in which anionic blood proteins with a pI lower than the pK(0) 6.78 of chitosan (the upper limit of chitosan pK(a)) associate electrostatically with cationic chitosan particles. Zymosan, a yeast ghost particle, activated complement in serum and citrated plasma, but not in EDTA-serum or methylamine plasma, to generate fluid-phase C5a, while C3b formed covalent cross-links with zymosan-associated proteins and became rapidly cleaved to iC3b, with factor Bb stably associated. These data demonstrate that chitosan is a nonreactive biomaterial that does not directly activate complement, and provide a novel basis for predicting anionic serum protein-chitosan interactions.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1552-4965
pubmed:author
pubmed:copyrightInfo
(c) 2009 Wiley Periodicals, Inc.
pubmed:issnType
Electronic
pubmed:day
15
pubmed:volume
93
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1429-41
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
C3, C5, and factor B bind to chitosan without complement activation.
pubmed:affiliation
Institute of Biomedical Engineering, Ecole Polytechnique, Montréal, Quebec, Canada H3C 3A7.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't