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B Cells and T Cells

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Regulatory T Cells (Tregs)

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Summary

Regulatory T-cells (Tregs) are a type of T-cell that regulate and suppress the immune response. Regulatory T-cells exert profound anti-inflammatory effects, in part by producing TGF-beta and Interleukin-10 (IL-10). Tregs constitutively express CD25 on their surface, but are more specifically identified by their expression of the FOXP3 transcription factor. The production of Regulatory T-cells is induced by a combination of Interleukin-2 (IL-2) and TGF-beta, and it is inhibited by Interleukin-6 (IL-6).

Key Points

  • Regulatory T Cells (Tregs)
    • Subtype of T cells that regulate and suppress suppresses immune responses
      • Prevents autoimmunity by maintaining tolerance to self-antigens
    • Express CD25 (non-specific) and FOXP3 (specific)
      • CD25 may also be expressed by activated Helper and Killer T-cells (nonspecific)
      • FOXP3 expression is relatively specific for Tregs, which are also called FOXP3+ T-cells
    • Induced by TGF-beta
      • Also stimulated by Interleukin-2 (IL-2), but in non-specific manner (IL-2 stimulates all lymphocytes)
      • TGF-beta also is produced by Tregs in a self-promoting fashion
    • Inhibited by Interleukin-6 (IL-6)
      • major pro-inflammatory cytokine which functions to cross-inhibit Tregs
    • Produces anti-inflammatory cytokines