Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1989-6-2
pubmed:abstractText
The two types of human C4, C4A and C4B, differ in their amino acid sequence and in their capacity to bind to different acceptor sites. C4B is more efficient than C4A in haemolytic assays; by contrast C4A binds preferentially to immune complexes. In assays comparing haemolysis to processing of immune complexes the two types of C4 differ more than fivefold. Thus, the classical pathway is a duplicated system that allows the formation of a C3 convertase on various substrates: this duplication may be of vital importance to eliminate invading microorganisms. In addition, the clinical observation of an increased incidence of homozygous C4A null alleles in systemic lupus erythematosus may be explained in part by defective processing of immune complexes in the absence of C4A.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1012-8204
pubmed:author
pubmed:issnType
Print
pubmed:volume
6
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
19-26
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Two isotypes of human C4, C4A and C4B have different structure and function.
pubmed:affiliation
Département de Médecine, Hôpital Cantonal Universitaire, Geneva, Switzerland.
pubmed:publicationType
Journal Article, Review, Research Support, Non-U.S. Gov't