Expression of the genes of interferons and other cytokines in normal and diseased tissues of man.

Specific interferon genes are transcribed at low levels in the spleen, liver, and peripheral blood leukocytes of normal individuals in the apparent absence of virus infection while other interferon genes remain unexpressed in the same tissues. In contrast, the genes of cytokines such as IL-1, IL-6 and TNF are expressed at relatively high levels in the organs of normal individuals. The level of expression of the IL-1, IL-6 and TNF genes is markedly reduced in the livers of patients with autoimmune liver disease compared to the level of expression in the liver of normal individuals, whereas the expression of interferon genes is similar in both normal and diseased liver, suggesting that a defect in the expression of specific cytokines is associated with severe liver disease.