In vitro binding analysis of hepatitis B virus preS-derived putative helper T-cell epitopes to MHC class II molecules using stable HLA-DRB1*0405/DRA*0101 transfected cells.
In designing epitope-based vaccines, the inclusion of a helper T-lymphocyte (HTL) epitope is necessary to elicit both humoral and cellular immune responses. Whereas the preS region of the hepatitis B virus (HBV) surface antigen is well-known to raise protective immunity, the epitopes for activating HTLs are poorly characterized. In an attempt to identify such epitopes, the HBV-preS region was screened for peptide sequences with HLA-DR4 binding motifs, and putative HTL candidate peptides were synthesized in a biotinylated form. Using L929 mouse fibroblasts stably transfected with HLA-DRB1*0405 and HLA-DRA*0101 cDNA, specific binding of the peptides was then detected using fluorescence-conjugated streptavidin. The cell-surface expression of HLA-DR molecules on transfectants was confirmed by confocal microscopy, and quantitative analysis of candidate peptide binding was performed by fluorescence activated cell sorting. Among eight preS-derived peptides, three candidate peptides-namely preS1(23-33), preS1(62-72), and preS1(76-86)-showed good binding characteristics to HLA-DR4 molecules, among which the preS1(23-33) epitope was regarded as the most promising HTL epitope. Further studies with these candidate HTL stimulatory peptides will show their ability to activate the human immune system against HBV.
Kim
J H
JH
Protein Engineering Laboratory, Korea Research Institute of Bioscience and Biotechnology, Yusong, Taejon, South Korea.
Park
J H
JH
Lee
Y J
YJ
Cho
E W
EW
Bae
Y S
YS
Kim
K L
KL
D000818:Animals; D001665:Binding Sites; D002478:Cells, Cultured; D000939:Epitopes / Q000378:metabolism*; D006684:HLA-DR Antigens / Q000235:genetics / Q000276:immunology*; D059805:HLA-DR alpha-Chains; D059811:HLA-DRB1 Chains; D006514:Hepatitis B Surface Antigens / Q000276:immunology*; D006801:Humans; D051379:Mice; D011498:Protein Precursors / Q000276:immunology*; D015203:Reproducibility of Results; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology* / Q000821:virology; D014162:Transfection
D000939:Epitopes; D006684:HLA-DR Antigens; D059805:HLA-DR alpha-Chains; D059811:HLA-DRB1 Chains; D006514:Hepatitis B Surface Antigens; D011498:Protein Precursors; C050806:presurface protein 1, hepatitis B surface antigen