Figure 1
From: IL-10 production by CD4+ effector T cells: a mechanism for self-regulation
Stable vs. conditional expression of interleukin (IL)-10 in Th effector subsets. Antigen-activated naive CD4+ T lymphocytes can adopt at least three distinct effector phenotypes as directed by cytokines within the local environment. In the presence of IL-4 they differentiate into Th2 cells, which in addition to IL-4, -5, and -13 also stably express IL-10 (without the requirement for IL-4 instruction during subsequent stimulation). IL-12 promotes Th1 differentiation by inducing interferon-γ (IFN-γ) synthesis. Although Th1 lymphocytes can also express IL-10, their production of the cytokine is not stable. Similarly, Th17 effectors, generated in the presence of IL-6 and transforming growth factor-β (TGF-β) and characterized by IL-17 expression (with or without IL-22), can secrete IL-10 under the correct set of conditions.
