Linked Life Data

11937567

Source:http://linkedlifedata.com/resource/pubmed/id/11937567

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
2002-4-8
pubmed:abstractText
We examined complement activation by Neisseria gonorrhoeae via the mannan-binding lectin (MBL) pathway in normal human serum. Maximal binding of MBL complexed with MBL-associated serine proteases (MASPs) to N. gonorrhoeae was achieved at a concentration of 0.3 microg/ml. Preopsonization with MBL-MASP at concentrations as low as 0.03 microg/ml resulted in approximately 60% killing of otherwise fully serum-resistant gonococci. However, MBL-depleted serum (MBLdS) reconstituted with MBL-MASP before incubation with organisms (postopsonization) failed to kill at a 100-fold higher concentration. Preopsonized organisms showed a 1.5-fold increase in C4, a 2.5-fold increase in C3b, and an approximately 25-fold increase in factor Bb binding; enhanced C3b and factor Bb binding was classical pathway dependent. Preopsonization of bacteria with a mixture of pure C1-inhibitor and/or alpha(2)-macroglobulin added together with MBL-MASP, all at physiologic concentrations before adding MBLdS, totally reversed killing in 10% reconstituted serum. Reconstitution of MBLdS with supraphysiologic (24 microg/ml) concentrations of MBL-MASP partially overcame the effects of inhibitors (57% killing in 10% reconstituted serum). We also examined the effect of sialylation of gonococcal lipooligosaccharide (LOS) on MBL function. Partial sialylation of LOS did not decrease MBL or C4 binding but did decrease C3b binding by 50% and resulted in 80% survival in 10% serum (lacking bacteria-specific Abs) even when sialylated organisms were preopsonized with MBL. Full sialylation of LOS abolished MBL, C4, and C3b binding, resulting in 100% survival. Our studies indicate that MBL does not participate in complement activation on N. gonorrhoeae in the presence of "complete" serum that contains C1-inhibitor and alpha(2)-macroglobulin.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
168
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4078-86
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:11937567-Adult, pubmed-meshheading:11937567-Binding Sites, Antibody, pubmed-meshheading:11937567-Carrier Proteins, pubmed-meshheading:11937567-Collectins, pubmed-meshheading:11937567-Complement C1 Inactivator Proteins, pubmed-meshheading:11937567-Complement Pathway, Classical, pubmed-meshheading:11937567-Cytidine Monophosphate N-Acetylneuraminic Acid, pubmed-meshheading:11937567-Dose-Response Relationship, Immunologic, pubmed-meshheading:11937567-Drug Synergism, pubmed-meshheading:11937567-Humans, pubmed-meshheading:11937567-Lectins, pubmed-meshheading:11937567-Lipopolysaccharides, pubmed-meshheading:11937567-Mannans, pubmed-meshheading:11937567-N-Acetylneuraminic Acid, pubmed-meshheading:11937567-Neisseria gonorrhoeae, pubmed-meshheading:11937567-Opsonin Proteins, pubmed-meshheading:11937567-Protein Binding, pubmed-meshheading:11937567-Serum Bactericidal Test, pubmed-meshheading:11937567-alpha-Macroglobulins
pubmed:year
2002
pubmed:articleTitle
Regulation of the mannan-binding lectin pathway of complement on Neisseria gonorrhoeae by C1-inhibitor and alpha 2-macroglobulin.
pubmed:affiliation
Section of Infectious Diseases and Hematology-Oncology, Evans Biomedical Research Center, Boston University Medical Center, Boston, MA 02118, USA. sgulati@bu.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.