Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1999-7-29
pubmed:abstractText
The protective epitope of the type III group B streptococcal polysaccharide (GBSPIII) is length dependent and conformational. To obtain a more accurate characterization of the conformational epitope, ELISA inhibition and surface plasmon resonance studies were conducted on two GBSPIII-specific mAbs using a large panel of oligosaccharide probes. The results of the studies confirmed that 2 repeating units (RU) is the minimum binding unit and that, while increases in chain length from 2 RU to 7 RU caused further optimization of the epitope, it remained monovalent. A 3-fold increase in affinity was observed between 7 RU and 20 RU, which, by surface plasmon resonance studies on a Fab, was shown to be due to both further optimization of the individual epitope and the occurrence of multivalency of epitope. The data support our hypothesis that the conformational epitope is an extended helical segment of the GBSPIII. GBSPIII exists mainly in the random coil form, which structurally mimics short oligosaccharide self Ags, but it can infrequently and spontaneously form extended helices. Although not prevalent in GBSPIII, the immune system preferentially selects these helical epitopes because they are unique to the polysaccharide. Contrary to a previously proposed model of GBSPIII binding in which the binding of the first Ab propagates a continuum of helical epitopes, our binding kinetics are consistent only with the helical epitope's being discontinuous and infrequent.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
163
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
820-5
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:10395675-Animals, pubmed-meshheading:10395675-Antigens, Bacterial, pubmed-meshheading:10395675-Binding, Competitive, pubmed-meshheading:10395675-Binding Sites, Antibody, pubmed-meshheading:10395675-Carbohydrate Conformation, pubmed-meshheading:10395675-Carbohydrate Sequence, pubmed-meshheading:10395675-Epitopes, pubmed-meshheading:10395675-Female, pubmed-meshheading:10395675-Glycoconjugates, pubmed-meshheading:10395675-Humans, pubmed-meshheading:10395675-Kinetics, pubmed-meshheading:10395675-Mice, pubmed-meshheading:10395675-Mice, Inbred BALB C, pubmed-meshheading:10395675-Molecular Sequence Data, pubmed-meshheading:10395675-Polysaccharides, Bacterial, pubmed-meshheading:10395675-Serum Albumin, pubmed-meshheading:10395675-Streptococcus agalactiae, pubmed-meshheading:10395675-Surface Plasmon Resonance
pubmed:year
1999
pubmed:articleTitle
Conformational epitope of the type III group B Streptococcus capsular polysaccharide.
pubmed:affiliation
Institute for Biological Sciences, National Research Council of Canada, Ottawa.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't