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More MS news articles for January 2004

CD4 T-cell epitopes of human alpha B-crystallin

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=14743435&dopt=Abstract

J Neurosci Res. 2004 Feb 15;75(4):516-23
Chou YK, Burrows GG, LaTocha D, Wang C, Subramanian S, Bourdette DN, Vandenbark AA.
Department of Neurology, Oregon Health and Science University, Portland, Oregon.

Of potential importance to multiple sclerosis (MS), oligodendroglial alpha B-crystallin is expressed and associated with the myelin sheath at the earliest stage of MS lesion development.

We selected T-cell lines specific for human alpha B-crystallin from peripheral blood mononuclear cells (PBMC) of HLA-DR2 homozygous MS patients and found that the alpha B-crystallin-specific T-cells were CD4+ and restricted by DRB1*1501, and expressed Th1 cytokines.

The CD4 T-cell epitopes of human alpha B-crystallin were determined by proliferation of alpha B-crystallin-specific T-cell lines to 17 20-mer synthetic overlapping peptides spanning the entire molecule of human alpha B-crystallin.

It was found that the HLA-DR2 donor-derived alpha B-crystallin-specific T-cell lines proliferated to alpha B-crystallin peptides 21-40, 41-60, and to a lesser extent, 131-150.

These T-cell proliferation responses were associated with intracellular expression of interleukin-2 (IL-2) and secretion of interferon-gamma (IFN-gamma), and tumor necrosis factor-alpha (TNF-alpha).

The amino acid sequences of these peptides were compatible with predicted HLA-DR2-restricted binding motifs.

PBMC of an early active MS patient proliferated to the epitope-containing peptides significantly better than did those of later stage MS patients or healthy controls.

Taken together, these findings suggest that autoreactive alpha B-crystallin-specific Th1 cells may have the potential to contribute to MS pathogenesis.