Linked Life Data

12794146

Source:http://linkedlifedata.com/resource/pubmed/id/12794146

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2003-6-9
pubmed:abstractText
Streptococcus pneumoniae is an important cause of morbitity and mortality worldwide. Capsule-specific IgG1 and IgG2 Abs are induced upon vaccination with polysaccharide-based vaccines that mediate host protection. We compared the protective capacity of human recombinant serogroup 6-specific IgG1 and IgG2 Abs in mice deficient for either leukocyte FcR or complement factors. Human IgG1 was found to interact with mouse leukocyte FcR in vitro, whereas human IgG2 did not. Both subclasses induced complement activation, resulting in C3c deposition on pneumococcal surfaces. Passive immunization of C57BL/6 mice with either subclass before intranasal challenge with serotype 6A induced similar degrees of protection. FcgammaRI- and III-deficient mice, as well as the combined FcgammaRI, II, and III knockout mice, were protected by passive immunization, indicating FcR not to be essential for protection. C1q or C2/factor B knockout mice, however, were not protected by passive immunization. Passively immunized C2/factor B(-/-) mice displayed higher bacteremic load than C1q(-/-) mice, supporting an important protective role of the alternative complement pathway. Spleens from wild-type and C1q(-/-) mice showed hyperemia and thrombotic vessel occlusion, as a result of septicemic shock. Notably, thrombus formation was absent in spleens of C2/factor B(-/-) mice, suggesting that the alternative complement pathway contributes to shock-induced intravascular coagulation. These studies demonstrate complement to play a central role in Ab-mediated protection against pneumococcal infection in vivo, as well as in bacteremia-associated thrombotic complications.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0022-1767
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
170
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6158-64
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:12794146-Animals, pubmed-meshheading:12794146-Antibodies, Bacterial, pubmed-meshheading:12794146-Antibody Specificity, pubmed-meshheading:12794146-Complement System Proteins, pubmed-meshheading:12794146-Humans, pubmed-meshheading:12794146-Immunization, Passive, pubmed-meshheading:12794146-Immunoglobulin G, pubmed-meshheading:12794146-Lung, pubmed-meshheading:12794146-Mice, pubmed-meshheading:12794146-Mice, Inbred BALB C, pubmed-meshheading:12794146-Mice, Inbred C57BL, pubmed-meshheading:12794146-Mice, Knockout, pubmed-meshheading:12794146-Pneumonia, Pneumococcal, pubmed-meshheading:12794146-Polysaccharides, Bacterial, pubmed-meshheading:12794146-Receptors, IgG, pubmed-meshheading:12794146-Sepsis, pubmed-meshheading:12794146-Spleen, pubmed-meshheading:12794146-Streptococcus pneumoniae
pubmed:year
2003
pubmed:articleTitle
Central role of complement in passive protection by human IgG1 and IgG2 anti-pneumococcal antibodies in mice.
pubmed:affiliation
Immunotherapy Laboratory, Department of Immunology, University Medical Center Utrecht, Utrecht, The Netherlands.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't