Activation of myelin reactive T cells in multiple sclerosis: a possible role for T cell degeneracy?
While it is widely accepted that myelin reactive T cells are key players in the immunopathogenesis of multiple sclerosis (MS), the initial triggers that turn on these self-reactive T-cells remain to be determined. One mechanism, which is already text book knowledge for a decade, is molecular mimicry by which viral or microbial antigens are able to cross-activate T cells specific for myelin epitopes, the major target in MS pathology. Although proof of concept for this principle was given in animal model studies, evidence for such a mechanism in MS is limited. In this issue, Zhang et al. demonstrate an increased frequency of T cells that cross-react with a wide variety of antigens, a phenomenon termed as T cell degeneracy. While the role of these degenerate T cells in MS remains to be determined the authors now provide new elegant tools to study this T cell population, thus providing a starting point to better understand their function in MS.
Stinissen
Piet
P
Biomedical Research Institute, Hasselt University, Agoralaan, Diepenbeek, Belgium. piet.stinissen@uhasselt.be
Hellings
Niels
N
D015551:Autoimmunity / Q000276:immunology; D018984:Epitopes, T-Lymphocyte / Q000276:immunology; D015802:HLA-DR2 Antigen / Q000276:immunology; D006801:Humans; D008213:Lymphocyte Activation / Q000276:immunology; D009103:Multiple Sclerosis / Q000276:immunology*; D009185:Myelin Proteins / Q000276:immunology*; D010455:Peptides / Q000276:immunology; D011948:Receptors, Antigen, T-Cell / Q000276:immunology; D016176:T-Lymphocyte Subsets / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology*
D018984:Epitopes, T-Lymphocyte; D015802:HLA-DR2 Antigen; D009185:Myelin Proteins; D010455:Peptides; D011948:Receptors, Antigen, T-Cell