Send to

Choose Destination
See comment in PubMed Commons below
J Allergy Clin Immunol. 2010 Aug;126(2):280-9, 289.e1-7. doi: 10.1016/j.jaci.2010.05.022. Epub 2010 Jul 10.

Inducible costimulator (ICOS) is a marker for highly suppressive antigen-specific T cells sharing features of TH17/TH1 and regulatory T cells.

Author information

Université Lyon1, Faculté de Médecine Lyon Sud, Lyon, France.



CD4(+)CD25(+) regulatory T (Treg) cells are involved in the downmodulation of numerous immune responses to pathogens, tumors, or allergens.


In this study, we further characterized the nature of Treg cells that control skin inflammatory reactions to haptens.


In a model of contact hypersensitivity to 2,4-dinitro-fluorobenzene, we have investigated the phenotype, the specificity, and the origin of Treg cells that modulate the priming of effector CD8(+) T cells responsible for the development of the pathology.


2,4-Dinitrofluorobenzene immunization induced a population of CD4(+)CD25(+) Treg cells that controlled CD8(+) T-cell effector responses in a hapten-specific manner in vivo. High levels of inducible costimulator (ICOS) expression defined a population of CD4(+)CD25(+)FoxP3(+) (forkhead box protein 3) Treg cells that presented superior suppressive activity. Importantly, ICOS(+) Treg cells were distinguishable from all other FoxP3(+) Treg cells by the expression of IL-10, IL-17, and IFN-gamma. Hapten-specific Treg cells proliferating in response to their cognate antigen in vivo predominantly displayed a CD25(+)FoxP3(+)ICOS(+) phenotype. By using reporter mice, we showed that ICOS(+) Treg cells derived from the expansion of natural CD4(+)FoxP3(+) Treg cells rather than generation of adaptive Treg cells. Furthermore, the generation of ICOS(+) Treg cells depended on innate cells rather than the effector CD8(+) T-cell population.


Taken together, our data show that a population of CD4(+)CD25(+)FoxP3(+) T cells upregulates ICOS on in vivo sensitization and specifically suppresses hapten-reactive CD8(+) T cells both in vivo and in vitro.

[Indexed for MEDLINE]
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Elsevier Science
    Loading ...
    Support Center