Pathogenicity of T cells responsive to diverse cryptic epitopes of myelin basic protein in the Lewis rat
Mor, F.; Cohen, I.R.
Journal of Immunology 155(7): 3693-3699
1995
ISSN/ISBN: 0022-1767 PMID: 7561070 Document Number: 453410
The cellular immunology of experimental autoimmune encephalomyelitis, a model for multiple sclerosis, has been studied, for the most part, using T cells directed to dominant epitopes of the Ag myelin basic protein (MBP). To characterize T cells reactive to cryptic epitopes of MBP, we immunized Lewis rats with each of 17 overlapping peptides of the 18.5-kDa isoform of rat MBP. We found that, in addition to the known 71-90 epitope, six other peptides induced active encephalomyelitis in the majority of the injected rats. T cell lines raised to six different MBP epitopes were encephalitogenic upon adoptive transfer to naive rats. In contrast to the T cells specific for the dominant 71-90 peptide, the T cell lines reactive to cryptic epitopes were not restricted in their TCR genes to V-beta-8.2, and some of the lines caused prolonged disease. Thus, T cells of different specificities and TCR usage can be pathogenic.