Regulatory T cells (Tregs) express all of the following, except:

Regulatory T cells (Tregs) A population of T cells called regulatory T cells functions to prevent immune reactions against self antigens. Regulatory T cells develop mainly in the thymus, as a result of recognition of self antigens, but they may also be induced in peripheral lymphoid tissues. The best-defined regulatory T cells are CD4+ cells that express high levels of CD25, the a chain of the IL-2 receptor, and FOXP3, a transcription factor of the forkhead family. Both IL-2 and FOXP3 are required for the development and maintenance of functional CD4+ regulatory T cells. Mutations in FOXP3 in humans result in autoimmune disorder called IPEX syndrome (immune dysregulation, polyendocrinopathy, enteropathy, X-linked).