Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2005-4-4
pubmed:abstractText
The serum lectins mannose-binding lectin (MBL), L-ficolin, and H-ficolin are recognition molecules in the lectin complement pathway, which play an important role in innate immunity. To assess involvement of the lectin pathway in the clearance of apoptotic cells, we used flow cytometry to quantify binding of MBL, L-ficolin, and H-ficolin to apoptotic HL60, U937, and Jurkat cells induced by actinomycin D. When apoptotic cells were incubated with normal human serum, MBL and L-ficolin bound to all three cell lines tested; moreover, H-ficolin bound to apoptotic Jurkat cells only. Subsequently, C4 and C3 were deposited on apoptotic cells of all three cell lines. MBL, L-ficolin, and H-ficolin binding to apoptotic cells was confirmed by the use of purified proteins. Purified C4 added to apoptotic cells that had bound pure L-ficolin was deposited on the cell surfaces. In L-ficolin-depleted serum, C3 deposition on HL60 or Jurkat cells decreased to approximately 50% or 70%, respectively, in comparison to the serum before L-ficolin depletion. We conclude that L-ficolin, in addition to MBL, recognizes apoptotic cells and activates complement via the lectin pathway. We also observed in vitro binding of L-ficolin and H-ficolin to cC1q receptor (C1q receptor specific for the collagenous region of C1q)/calreticulin, a candidate receptor for the collagenous region of MBL and C1q. Thus, L-ficolin and H-ficolin as well as MBL participate in the clearance of apoptotic cells through complement activation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Calreticulin, http://linkedlifedata.com/resource/pubmed/chemical/Complement C1q, http://linkedlifedata.com/resource/pubmed/chemical/Complement C3, http://linkedlifedata.com/resource/pubmed/chemical/Complement C4, http://linkedlifedata.com/resource/pubmed/chemical/Complement System Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Dactinomycin, http://linkedlifedata.com/resource/pubmed/chemical/Lectins, http://linkedlifedata.com/resource/pubmed/chemical/Mannose-Binding Lectin, http://linkedlifedata.com/resource/pubmed/chemical/Membrane Glycoproteins, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Complement, http://linkedlifedata.com/resource/pubmed/chemical/complement 1q receptor, http://linkedlifedata.com/resource/pubmed/chemical/ficolin
pubmed:status
MEDLINE
pubmed:issn
0171-2985
pubmed:author
pubmed:issnType
Print
pubmed:volume
209
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
689-97
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Specific binding of L-ficolin and H-ficolin to apoptotic cells leads to complement activation.
pubmed:affiliation
Department of Biochemistry, School of Medicine, Fukushima Medical University, 1-Hikariga-oka, Fukushima 960-1295, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't