title: Priming of autoreactive CD8(+) T cells is inhibited by immunogenic peptides which are competitive for major histocompatibility complex class I binding.
abstract: In the present study, we investigated if priming of autoreactive CD8(+) T cells would be inhibited by competitive peptides for major histocompatibility complex (MHC) class I binding. We used a mouse model of vitiligo which is induced by immunization of K(b)-binding tyrosinase-related protein 2 (TRP2)-180 peptide. Competitive peptides for K(b) binding inhibited IFN-γ production and proliferation of TRP2-180-specific CD8(+) T cells upon ex vivo peptide restimulation, while other MHC class I-binding peptides did not. In mice, the capability of inhibition was influenced by T-cell immunogenicity of the competitive peptides. The competitive peptide with a high T-cell immunogenicity efficiently inhibited priming of TRP2-180-specific CD8(+) T cells in vivo, whereas the competitive peptide with a low T-cell immunogenicity did not. Taken together, the inhibition of priming of autoreactive CD8(+) T cells depends on not only competition of peptides for MHC class I binding but also competitive peptide-specific CD8(+) T cells, suggesting that clonal expansion of autoreactive T cells would be affected by expansion of competitive peptide-specific T cells. This result provides new insights into the development of competitive peptides-based therapy for the treatment of autoimmune diseases.
authors.affiliation: Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon 305-701, Korea.
authors.forename: Sooseong
authors.initials: S
authors.lastname: You
authors.forename: Yoon Seok
authors.initials: YS
authors.lastname: Choi
authors.forename: Seokchan
authors.initials: S
authors.lastname: Hong
authors.forename: Eui-Cheol
authors.initials: EC
authors.lastname: Shin
keywords: Autoimmune disease; Autoreactive CD8+ T cell; Competitive peptide; Major histocompatibility complex class I