Abstract
CTLA-4 is thought to inhibit effector T cells both intrinsically, by competing with CD28 for B7 ligands, and extrinsically, through the action of regulatory T cells (Tregs). We studied in vivo responses of normal and CTLA-4-deficient Ag-specific murine effector CD4 + T cells. We directly demonstrate that effector T cellrestricted CTLA-4 inhibits T cell responses in a cellextrinsic manner. Cotransfer experiments show that CTLA-4 on normal effector CD4 + T cells completely abrogates the dramatically increased expansion normally experienced by their CTLA-4-deficient counterparts. Neither the wild-type nor the CTLA-4-deficient T cells express the Treg transcription factor Foxp3 when transferred alone or together. Thus, cell-extrinsic inhibition of T cell responses by CTLA-4 is not limited to Tregs but is also a function of effector T cells.
Original language | English (US) |
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Pages (from-to) | 1123-1127 |
Number of pages | 5 |
Journal | Journal of Immunology |
Volume | 189 |
Issue number | 3 |
DOIs | |
State | Published - Aug 1 2012 |
Externally published | Yes |
ASJC Scopus subject areas
- Immunology and Allergy
- Immunology