Page 626 - Veterinary Immunology, 10th Edition

VetBooks.ir Regulatory Cells

Although much immune regulation is “passive” in that self-reactive
lymphocytes are eliminated by central tolerance, cells in peripheral

tissues also “actively” regulate the immune system. Cells with
regulatory functions include T cells, B cells, macrophages, dendritic
cells, and natural suppressor cells.

Regulatory T Cells

Regulatory T cells (called Tregs) play a master role in regulating the
immune system and maintaining the balance between peripheral
tolerance and immunity (Fig. 20.10). In their absence, multiorgan
autoimmune disease or uncontrolled inflammation results. Some of

these Treg cells develop naturally, whereas others are induced by
cytokine exposure.

FIG. 20.10 The production and functions of regulatory T cells.
They are generated by the combined actions of IL-2 and TGF-β as
well as the presence of retinoic acid. They characteristically
produce the suppressive cytokines, TGF-β, IL-10, and IL-35.

626