T-cell subsets in autoimmunity.

Although differential cytokine production has been best characterized in CD4+ T cells, it is becoming clear that CD8+ T cells may also be heterogeneous at the level of cytokine production, and that this determines whether they exhibit inflammatory- or suppressor-type properties. Compelling evidence has accumulated in the past few years that cytokines such as interleukin-4, interleukin-10 and transforming growth factor-beta may serve as regulators of cell-mediated immunopathologies by inhibiting the development or effector function of inflammatory T cells that produce cytokines such as interferon-gamma or lymphotoxin.