Open AccessMolecular basis for antibody cross‐reactivity between the hepatitis C virus core protein and the host‐derived GOR protein
Author(s) -
ZHANG Z. X.,
CHEN M.,
AGEN K. WALLH,
TROJNAR J.,
MAGNIUS L. O.,
WAHRKN B.,
SÄLLBERG M.
Publication year - 1994
Publication title -
clinical & experimental immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.329
H-Index - 135
eISSN - 1365-2249
pISSN - 0009-9104
DOI - 10.1111/j.1365-2249.1994.tb06042.x
Subject(s) - avidity , antibody , virology , cross reactivity , antigen , hepatitis c virus , molecular mimicry , biology , epitope , virus , chemistry , immunology , cross reactions
SUMMARY The presence of antibodies reactive to a recently cloned host‐derived antigen GOR is highly correlated with the presence of antibodies to the hepatitis C virus (HCV), We explored the molecular basis for this observation, and address the following question: are antibodies reactive with GOR 19‐27 (QKAKSNPNR) a result of a cross‐reactivity triggered by the antigenic region at residues 9‐17 of HCV core (RKTKRNTNR)? We compared the relative antibody avidity between antibodies reactive to both regions, and determined the residues essential for antibody binding using substitution peptide analogues. Of 96 sera assayed, 60 were found positive for anti‐HCV, and of these 55 were found to react with HCV core. Twenty‐nine sera were found reactive to the GOR peptide, and these were all reactive to HCV core. In most cases the relative antibody avidity of antibodies reactive to GOR was higher for the HCV core peptide. In 21 of the GOR‐reactive sera we were able to determine the essential residues for antibody binding. The essential residues in > 50% of all tested sera coincided with the well conserved residues Lys 10 , Lys 12 , Asn 14 , and Asn 16 . Also, reactivity to GOR was not related to any certain serotype of antibodies to HCV. Taken together, these findings explain at the molecular level the observed cross‐reactivity between these two proteins, since sequence homology per se is not evidence for cross‐reactivity.