Open AccessCutting Edge: IL-4-Induced Protection of CD4+CD25− Th Cells from CD4+CD25+ Regulatory T Cell-Mediated Suppression
Author(s) -
Luigia Pace,
Stefania Rizzo,
Cecilia Palombi,
Frank Brombacher,
Gino Doria
Publication year - 2006
Publication title -
the journal of immunology/the journal of immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.737
H-Index - 372
eISSN - 1550-6606
pISSN - 0022-1767
DOI - 10.4049/jimmunol.176.7.3900
Subject(s) - il 2 receptor , microbiology and biotechnology , t cell , interleukin 21 , biology , cell growth , immune system , immunology , biochemistry
CD4(+)CD25(+) T regulatory (Treg) cells are a CD4(+) T cell subset involved in the control of the immune response. In vitro, murine CD4(+)CD25(+) Treg cells inhibit CD4(+)CD25(-) Th cell proliferation induced by anti-CD3 mAb in the presence of APCs. The addition of IL-4 to cocultured cells inhibits CD4(+)CD25(+) Treg cell-mediated suppression. Since all cell types used in the coculture express the IL-4Ralpha chain, we used different combinations of CD4(+)CD25(-) Th cells, CD4(+)CD25(+) Treg cells, and APCs from wild-type IL-4Ralpha(+/+) or knockout IL-4Ralpha(-/-) mice. Results show that the engagement of the IL-4Ralpha chain on CD4(+)CD25(-) Th cells renders these cells resistant to suppression. Moreover, the addition of IL-4 promotes proliferation of IL-4Ralpha(+/+)CD4(+)CD25(+) Treg cells, which preserve full suppressive competence. These findings support an essential role of IL-4 signaling for CD4(+)CD25(-) Th cell activation and indicate that IL-4-induced proliferation of CD4(+)CD25(+) Treg cells is compatible with their suppressive activity.