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Efficient induction of CD25- iTreg by co-immunization requires strongly antigenic epitopes for T cells.

ABSTRACT: BACKGROUND: We previously showed that co-immunization with a protein antigen and a DNA vaccine coding for the same antigen induces CD40 low IL-10 high tolerogenic DCs, which in turn stimulates the expansion of antigen-specific CD4+CD25-Foxp3+ regulatory T cells (CD25- iTreg). However, it was unclear how to choose the antigen sequence to maximize tolerogenic antigen presentation and, consequently, CD25- iTreg induction. RESULTS: In the present study, we demonstrated the requirement of highly antigenic epitopes for CD25- iTreg induction. Firstly, we showed that the induction of CD25- iTreg by tolerogenic DC can be blocked by anti-MHC-II antibody. Next, both the number and the suppressive activity of CD25- iTreg correlated positively with the overt antigenicity of an epitope to activate T cells. Finally, in a mouse model of dermatitis, highly antigenic epitopes derived from a flea allergen not only induced more CD25- iTreg, but also more effectively prevented allergenic reaction to the allergen than did weakly antigenic epitopes. CONCLUSIONS: Our data thus indicate that efficient induction of CD25- iTreg requires highly antigenic peptide epitopes. This finding suggests that highly antigenic epitopes should be used for efficient induction of CD25- iTreg for clinical applications such as flea allergic dermatitis.

SUBMITTER: Geng S

PROVIDER: S-EPMC3107816 | biostudies-literature | 2011

REPOSITORIES: biostudies-literature

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Efficient induction of CD25- iTreg by co-immunization requires strongly antigenic epitopes for T cells.

Geng Shuang S Yu Yang Y Kang Youmin Y Pavlakis George G Jin Huali H Li Jinyao J Hu Yanxin Y Hu Weibin W Wang Shuang S Wang Bin B

BMC immunology 20110505

<h4>Background</h4>We previously showed that co-immunization with a protein antigen and a DNA vaccine coding for the same antigen induces CD40 low IL-10 high tolerogenic DCs, which in turn stimulates the expansion of antigen-specific CD4+CD25-Foxp3+ regulatory T cells (CD25- iTreg). However, it was unclear how to choose the antigen sequence to maximize tolerogenic antigen presentation and, consequently, CD25- iTreg induction.<h4>Results</h4>In the present study, we demonstrated the requirement o ...[more]

PMID: 21542943

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Efficient induction of CD25- iTreg by co-immunization requires strongly antigenic epitopes for T cells.

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Efficient induction of CD25- iTreg by co-immunization requires strongly antigenic epitopes for T cells.

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