Reference
Reference TypeLiterature
TitleMapping of murine Th1 helper T-Cell epitopes of mycolyl transferases Ag85A, Ag85B, and Ag85C from Mycobacterium tuberculosis.
AuthorsS D'Souza; V Rosseels; M Romano; A Tanghe; O Denis; F Jurion; N Castiglione; A Vanonckelen; K Palfliet; Kris Huygen
AffiliationsMycobacterial Immunology, Pasteur Institute of Brussels, Brussels, Belgium.
JournalInfect Immun
Year2003
AbstractBALB/c (H-2(d)) and C57BL/6 (H-2(b)) mice were infected intravenously with Mycobacterium tuberculosis H37Rv or vaccinated intramuscularly with plasmid DNA encoding each of the three mycolyl transferases Ag85A, Ag85B, and Ag85C from M. tuberculosis. Th1-type spleen cell cytokine secretion of interleukin-2 (IL-2) and gamma interferon (IFN-gamma) was analyzed in response to purified Ag85 components and synthetic overlapping peptides covering the three mature sequences. Tuberculosis-infected C57BL/6 mice reacted strongly to some peptides from Ag85A and Ag85B but not from Ag85C, whereas tuberculosis-infected BALB/c mice reacted only to peptides from Ag85A. In contrast, spleen cells from both mouse strains produced elevated levels of IL-2 and IFN-gamma following vaccination with Ag85A, Ag85B, and Ag85C DNA in response to peptides of the three Ag85 proteins, and the epitope repertoire was broader than in infected mice. Despite pronounced sequence homology, a number of immunodominant regions contained component specific epitopes. Thus, BALB/c mice vaccinated with all three Ag85 genes reacted against the same amino acid region, 101 to 120, that was also immunodominant for Ag85A in M. bovis BCG-vaccinated and tuberculosis-infected H-2(d) haplotype mice, but responses were completely component specific. In C57BL/6 mice, a cross-reactive T-cell response was detected against two carboxy-terminal peptides spanning amino acids 241 to 260 and 261 to 280 of Ag85A and Ag85B. These regions were not recognized at all in C57BL/6 mice vaccinated with Ag85C DNA. Our results underline the need for comparative analysis of all three Ag85 components in future vaccination studies.
Curation Last Updated2023-08-18 20:03:06
Epitope
Epitope ID19579
Chemical TypeLinear peptide
Linear SequenceGFLNPSEGWWPTLIGLAMND
Source Molecule NameAntigen 85-C precursor
Source OrganismMycobacterium tuberculosis H37Rv (Mycobacterium tuberculosis str. H37Rv)
Starting Position195
Ending Position214
Epitope Reference Details
Epitope Structure DefinesEpitope containing region/antigenic site
Epitope NameAg85C 151-170
Reference Starting Position151
Reference Ending Position170
CommentsThe Swiss-Prot sequence numbering includes the signal sequence.
Location of Data in ReferenceTable 1
Immunization
Host OrganismMus musculus C57BL/6
1st In Vivo Process
In Vivo Process TypeAdministration in vivo
Administration Details
Routeintramuscular
Dose Schedule3 doses of 100 μg plasmid DNA 3 wks apart
1st Immunogen
Epitope RelationSource Antigen
Chemical TypeProtein
Molecule NameAntigen 85-C precursor
OrganismMycobacterium tuberculosis H37Rv (Mycobacterium tuberculosis str. H37Rv)
Immunization Comments
Immunization CommentsImmunogen carrier: Plasmid. Mice were immunized with three i.m. injections of 100ug pDNA encoding Ag85 (A, B or C). Spleens were removed 3 weeks after the last DNA immunization.
T Cell Assay
Qualitative MeasurementPositive
Method/TechniqueELISA
Measurement ofIFNg release
Effector Cells
Effector Cell Tissue TypeSpleen
Effector Cell TypeSplenocyte
Effector Cell Culture ConditionsDirect Ex Vivo
Antigen Presenting Cells
Cell Tissue TypeSpleen
Cell TypeSplenocyte
Cell Culture ConditionsDirect Ex Vivo
Antigen
Epitope RelationEpitope
Chemical TypeLinear peptide
Linear SequenceGFLNPSEGWWPTLIGLAMND
Source Molecule NameAntigen 85-C precursor
Source OrganismMycobacterium tuberculosis H37Rv (Mycobacterium tuberculosis str. H37Rv)
Starting Position195
Ending Position214
Assay Reference Details
Assay Comments by IEDB CuratorOverlapping 20-mers spanning the length of Ag85 were tested for reactivity using splenocytes from mice immunized with plasmid DNA encoding Ag85.
Location of Assay Data in ReferenceFigure 2