title: Mapping of TH1 helper T-cell epitopes on major secreted mycobacterial antigen 85A in mice infected with live Mycobacterium bovis BCG.
abstract: TH1 cytokine secretion was examined in response to synthetic peptides of the 85A component of the major secreted, fibronectin-binding antigen 85 complex from Mycobacterium tuberculosis in seven different mouse strains infected with live M. bovis BCG. Twenty-eight overlapping 20-mer peptides covering the complete mature 295-amino-acid (AA) protein were synthesized. Significant interleukin-2 (IL-2) and gamma interferon (IFN-gamma) secretion could be measured following in vitro stimulation of spleen cells with these peptides. H-2d haplotype mice reacted preferentially against the amino-terminal half of the protein, i.e., against peptide 5 (AA 41 to 60) and especially against peptide 11 (AA 101 to 120), which contained an I-Ed binding motif. H-2b haplotype mice, on the other hand, reacted against peptides from both amino- and carboxy-terminal halves of the protein, peptide 25 (AA 241 to 260) being the most potent stimulator of IL-2 and IFN-gamma production. (BALB/c x C57BL/6)F1 animals with the H-2d/b haplotype weakly recognized peptides specific for both parental lines. Finally, CBA/J (H-2k) and major histocompatibility complex class II mutant B6.C.bm12 mice, carrying a mutant I-A beta bm12 allele on an H-2b background, reacted only very weakly to the 85A peptides. Reactive T cells isolated from lungs of BCG-infected H-2b haplotype mice recognized the same epitopes as spleen cells, especially peptide 25. These data confirm previous findings regarding the powerful IL-2 and IFN-gamma-inducing properties of antigen 85 during infection with live M. bovis BCG.
authors.affiliation: Instituut Pasteur van Brabant, Hôpital Erasme (ULB), Brussels, Belgium.
authors.forename: K
authors.initials: K
authors.lastname: Huygen
authors.forename: E
authors.initials: E
authors.lastname: Lozes
authors.forename: B
authors.initials: B
authors.lastname: Gilles
authors.forename: A
authors.initials: A
authors.lastname: Drowart
authors.forename: K
authors.initials: K
authors.lastname: Palfliet
authors.forename: F
authors.initials: F
authors.lastname: Jurion
authors.forename: I
authors.initials: I
authors.lastname: Roland
authors.forename: M
authors.initials: M
authors.lastname: Art
authors.forename: M
authors.initials: M
authors.lastname: Dufaux
authors.forename: J
authors.initials: J
authors.lastname: Nyabenda
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics*; D016207:Cytokines / Q000096:biosynthesis / Q000378:metabolism; D000939:Epitopes / Q000235:genetics; D005260:Female; D008168:Lung / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008811:Mice, Inbred DBA; D008969:Molecular Sequence Data; D009163:Mycobacterium bovis / Q000235:genetics / Q000276:immunology*; D010449:Peptide Mapping; D010455:Peptides / Q000235:genetics / Q000276:immunology; D013045:Species Specificity; D013154:Spleen / Q000276:immunology; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*; D014376:Tuberculosis / Q000276:immunology / Q000517:prevention & control
chemical_list: D000942:Antigens, Bacterial; D016207:Cytokines; D000939:Epitopes; D010455:Peptides; C065036:antigen 85, Mycobacterium bovis