T- and B-cell epitopes in the secreted Mycobacterium bovis antigen MPB70 in mice.
MPB70 is a soluble secreted protein highly expressed in Mycobacterium bovis and strains of bacille Calmette-Guérin (BCG); as such, it is a candidate for subunit and DNA vaccines against tuberculosis. MPB70 was screened for T-cell epitopes in four different inbred mouse strains. Major histocompatibility complex (MHC) H-2b-expressing mice (C57BL/6) secreted interferon-gamma (IFN-gamma) after stimulation with peptides from the regions 1-20, 41-50, 81-110, 121-150 and 161-193 of the MPB70 sequence. H-2db mouse (B6D2) splenocytes secreted IFN-gamma after stimulation with some of the same peptides, whereas H-2d mice (BALB/c and DBA/2) did not secrete IFN-gamma upon stimulation with the peptides. Sera from H-2db mice immunized with native MPB70 in incomplete Freund's adjuvant (IFA), mpb70 DNA or live BCG Moreau were found to contain antibodies against the native MPB70 antigen. H-2db mice immunized with native MPB70 in IFA exhibited high titres of peptide-reactive immunoglobulin G1 (IgG1) antibodies, whereas DNA-immunized mice reacted with IgG2a antibodies against some of the same peptides. As some of the epitopes recognized by mouse T and B cells have previously been found to stimulate immune responses in humans, cattle and rabbits, we conclude that these epitopes may be good general epitopes for the stimulation of T- and B-cell responses and candidates for a DNA vaccine with a broad applicability.
Tollefsen
S
S
Institute of Immunology, Rikshospitalet, University of Oslo, Oslo, Norway. stig.tollefsen@labmed.uio.no
Pollock
J M
JM
Lea
T
T
Harboe
M
M
Wiker
H G
HG
D000595:Amino Acid Sequence; D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D001426:Bacterial Proteins / Q000276:immunology*; D018274:Electroporation; D004797:Enzyme-Linked Immunosorbent Assay; D018985:Epitopes, B-Lymphocyte / Q000276:immunology*; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D005620:Freund's Adjuvant / Q000494:pharmacology; D006183:H-2 Antigens / Q000276:immunology; D006239:Haplotypes; D064532:Histocompatibility Antigen H-2D; D007132:Immunoglobulin Isotypes / Q000096:biosynthesis; D007371:Interferon-gamma / Q000096:biosynthesis / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D008969:Molecular Sequence Data; D009163:Mycobacterium bovis / Q000276:immunology*; D010446:Peptide Fragments / Q000276:immunology; D014376:Tuberculosis / Q000276:immunology* / Q000517:prevention & control; D019444:Vaccines, DNA / Q000276:immunology* / Q000592:standards
D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D018985:Epitopes, B-Lymphocyte; D018984:Epitopes, T-Lymphocyte; D006183:H-2 Antigens; D064532:Histocompatibility Antigen H-2D; D007132:Immunoglobulin Isotypes; D010446:Peptide Fragments; D019444:Vaccines, DNA; C060216:MPB70 protein, Mycobacterium bovis; D007371:Interferon-gamma; D005620:Freund's Adjuvant