Natural T Cell Epitope Containing Methyl Lysines on Mycobacterial Heparin-Binding Hemagglutinin.
J Immunol
; 204(7): 1715-1723, 2020 04 01.
Article
in En
| MEDLINE
| ID: mdl-32122997
ABSTRACT
T cell epitopes are mostly nonmodified peptides, although posttranslationally modified peptide epitopes have been described, but they originated from viral or self-proteins. In this study, we provide evidence of a bacterial methylated T cell peptide epitope. The mycobacterial heparin-binding hemagglutinin (HBHA) is a protein Ag with a complex C-terminal methylation pattern and is recognized by T cells from humans latently infected with Mycobacterium tuberculosis By comparing native HBHA with recombinant HBHA produced in Mycobacterium smegmatis (rHBHA-Ms), we could link antigenic differences to differences in the methylation profile. Peptide scan analyses led to the discovery of a peptide containing methyl lysines recognized by a mAb that binds to native HBHA â¼100-fold better than to rHBHA-Ms This peptide was also recognized by T cells from latently infected humans, as evidenced by IFN-γ release upon peptide stimulation. The nonmethylated peptide did not induce IFN-γ, arguing that the methyl lysines are part of the T cell epitope.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
T-Lymphocytes
/
Epitopes, T-Lymphocyte
/
Lectins
/
Lysine
Limits:
Humans
Language:
En
Journal:
J Immunol
Year:
2020
Type:
Article
Affiliation country:
Belgium