Mapping of B-neutralizing and T-helper cell epitopes on the bovine leukemia virus external glycoprotein gp51.
A battery of 19 synthetic peptides was used to characterize efficient neutralizing and helper T-cell epitopes on the bovine leukemia virus (BLV) external envelope glycoprotein gp51. Four of the antipeptide antisera raised in rabbits inhibited the formation of BLV-induced syncytia; these antisera are directed against peptides 64-73, 98-117, and 177-192. Only antisera directed against the 177-192 region also neutralized vesicular stomatitis virus-BLV pseudotypes. This study clearly demonstrates that neutralizing properties can be observed with antibodies raised to regions undescribed so far and included in both the amino-terminal and central parts of the antigen. In addition, some helper T-cell determinants were defined from gp51-immunized mice and from BLV-infected cattle. Although none of the peptides tested behaved as a universal helper T-cell epitope, peptide 98-117 stimulated T-cell proliferation from BALB/c mice and from three infected cows, while peptide 169-188 strongly stimulated T-cell proliferation from one infected cow. Further experiments performed with three peptides overlapping the 169-188 region (177-192, 179-192, 181-192) demonstrated the particular relevance of residue(s) P-177 and/or D-178 in the helper T-cell epitope. These data should assist in the design of an efficient subunit vaccine against BLV infection that contains peptides possessing both B-neutralizing and helper T-cell determinants.
Callebaut
I
I
Microbiology Unit, Faculty of Agronomy, Gembloux, Belgium.
Vonèche
V
V
Mager
A
A
Fumière
O
O
Krchnak
V
V
Merza
M
M
Zavada
J
J
Mammerickx
M
M
Burny
A
A
Portetelle
D
D
D000595:Amino Acid Sequence; D000818:Animals; D001402:B-Lymphocytes / Q000276:immunology*; D002417:Cattle; D016583:Enzootic Bovine Leukosis / Q000382:microbiology; D000939:Epitopes / Q000032:analysis / Q000276:immunology*; D005260:Female; D015726:Giant Cells / Q000502:physiology; D007106:Immune Sera; D066298:In Vitro Techniques; D001909:Leukemia Virus, Bovine / Q000276:immunology* / Q000302:isolation & purification; D008213:Lymphocyte Activation; D051379:Mice; D008807:Mice, Inbred BALB C; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D010455:Peptides / Q000138:chemical synthesis / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D014759:Viral Envelope Proteins / Q000276:immunology*
D000939:Epitopes; D007106:Immune Sera; D010455:Peptides; D014759:Viral Envelope Proteins