Varicella zoster-specific CD4+Foxp3+ T cells accumulate after cutaneous antigen challenge in humans.

Autor: Vukmanovic-Stejic M; Division of Infection and Immunity, University College London, London W1T 4JF, United Kingdom., Sandhu D, Sobande TO, Agius E, Lacy KE, Riddell N, Montez S, Dintwe OB, Scriba TJ, Breuer J, Nikolich-Zugich J, Ogg G, Rustin MH, Akbar AN
Jazyk: angličtina
Zdroj: Journal of immunology (Baltimore, Md. : 1950) [J Immunol] 2013 Feb 01; Vol. 190 (3), pp. 977-86. Date of Electronic Publication: 2013 Jan 02.
DOI: 10.4049/jimmunol.1201331
Abstrakt: We investigated the relationship between varicella zoster virus (VZV)-specific memory CD4(+) T cells and CD4(+)Foxp3(+) regulatory T cells (Tregs) that accumulate after intradermal challenge with a VZV skin test Ag. VZV-specific CD4(+) T cells were identified with a MHC class II tetramer or by intracellular staining for either IFN-γ or IL-2 after Ag rechallenge in vitro. VZV-specific T cells, mainly of a central memory (CD45RA(-)CD27(+)) phenotype, accumulate at the site of skin challenge compared with the blood of the same individuals. This resulted in part from local proliferation because >50% of tetramer defined Ag-specific CD4(+) T cells in the skin expressed the cell cycle marker Ki67. CD4(+)Foxp3(+) T cells had the characteristic phenotype of Tregs, namely CD25(hi)CD127(lo)CD39(hi) in both unchallenged and VZV challenged skin and did not secrete IFN-γ or IL-2 after antigenic restimulation. The CD4(+)Foxp3(+) T cells from unchallenged skin had suppressive activity, because their removal led to an increase in cytokine secretion after activation. After VZV Ag injection, Foxp3(+)CD25(hi)CD127(lo)CD39(hi) T cells were also found within the VZV tetramer population. Their suppressive activity could not be directly assessed by CD25 depletion because activated T cells in the skin were also CD25(+). Nevertheless, there was an inverse correlation between decreased VZV skin responses and proportion of CD4(+)Foxp3(+) T cells present, indicating indirectly their inhibitory activity in vivo. These results suggest a linkage between the expansion of Ag-specific CD4(+) T cells and CD4(+) Tregs that may provide controlled responsiveness during Ag-specific stimulation in tissues.
Databáze: MEDLINE