Linked Life Data

10421400

Source:http://linkedlifedata.com/resource/pubmed/id/10421400

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1999-8-31
pubmed:abstractText
The emergence of variants in the outer envelope proteins of hepatitis B virus (HBV) are found among individuals vaccinated against HBV and asymptomatic carriers of the infection. For example, children in The Gambia vaccinated against hepatitis B may show serological evidence of breakthrough infections, particularly if anti-HBs antibodies induced by the vaccine are low in titre. A single-point mutation at nucleotide 421 of the S gene is associated with such breakthrough infections. In the present study, the antigenicity of variant HBV S protein expressed as HBsAg particles in a vaccinia virus expression system has been characterised using a panel of monoclonal antibodies directed against linear and conformational determinations of the S protein. A cellular ELISA procedure using expressed antigen in Vero cells revealed differences in reactivity using four of the six antibodies that had been raised against the adw subtype of HBV and recognise conformational epitopes in the a determinant. In two instances, an enhanced reactivity for the variant antigen was found, confirming that point mutations in the a determinant of the S protein between residues 139 and 147 may result in significant changes in conformation. These findings also demonstrate that there are distinct antigenic differences between the vaccine strains of HBsAg/ adw subtype and the predominant HBsAg subtype circulating in West Africa. The implications of this work are that serodiagnosis of HBV infections may be unreliable in populations where there is a possibility of variant HBV infections emerging in the face of increasing herd immunity to HBV as a result of vaccination, particularly using monoclonal antibody-based diagnostic tests. Such variants may play a role in the maintenance of HBV infections in endemic regions.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0146-6615
pubmed:author
pubmed:issnType
Print
pubmed:volume
58
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
346-52
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:10421400-Amino Acid Sequence, pubmed-meshheading:10421400-Amino Acid Substitution, pubmed-meshheading:10421400-Animals, pubmed-meshheading:10421400-Antibodies, Monoclonal, pubmed-meshheading:10421400-Cell Line, pubmed-meshheading:10421400-Cercopithecus aethiops, pubmed-meshheading:10421400-Child, pubmed-meshheading:10421400-Enzyme-Linked Immunosorbent Assay, pubmed-meshheading:10421400-Epitopes, pubmed-meshheading:10421400-Genetic Variation, pubmed-meshheading:10421400-Hepatitis B, pubmed-meshheading:10421400-Hepatitis B Antibodies, pubmed-meshheading:10421400-Hepatitis B Surface Antigens, pubmed-meshheading:10421400-Hepatitis B virus, pubmed-meshheading:10421400-Humans, pubmed-meshheading:10421400-Mice, pubmed-meshheading:10421400-Molecular Sequence Data, pubmed-meshheading:10421400-Protein Conformation, pubmed-meshheading:10421400-Recombinant Fusion Proteins, pubmed-meshheading:10421400-Sequence Homology, Amino Acid, pubmed-meshheading:10421400-Vaccination, pubmed-meshheading:10421400-Vaccinia virus, pubmed-meshheading:10421400-Vero Cells
pubmed:year
1999
pubmed:articleTitle
A hepatitis B virus variant found in the sera of immunised children induces a conformational change in the HBsAg "a" determinant.
pubmed:affiliation
Department of Pathology and Infectious Diseases, Royal Veterinary College, London, UK.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't