Promoting tolerance to proteolipid protein-induced experimental autoimmune encephalomyelitis through targeting dendritic cells.

Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA.
Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 10/2010; 107(40):17280-5. DOI: 10.1073/pnas.1010263107
Source: PubMed

ABSTRACT In T cell-mediated autoimmune diseases, self-reactive T cells with known antigen specificity appear to be particularly promising targets for antigen-specific induction of tolerance without compromising desired protective host immune responses. Several lines of evidence suggest that delivery of antigens to antigen-presenting dendritic cells (DCs) in the steady state (i.e., to immature DCs) may represent a suitable approach to induce antigen-specific T-cell tolerance peripherally. Here, we report that anti-DEC205-mediated delivery of the self-peptide proteolipid protein (PLP)139-151 to DCs ameliorated clinical symptoms in the PLP-induced SJL model of experimental autoimmune encephalomyelitis. Splenocytes from treated mice were anergized to PLP139-151, and IL-17 secretion was markedly reduced. Moreover, we show directly, using transgenic CD4(+) Vβ6(+) TCR T cells specific for PLP139-151, that, under the conditions of the present experiments, these cells also became anergic. In addition, evidence for a CD4(+) T cell-mediated suppressor mechanism was obtained.

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