TNF and Hepatitis: Con A-induced hepatitis is accompanied by an increase in the serum concentration of several proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interferon-γ (IFN-γ) and interleukin-1 (IL-1) [7], [8] which contribute to the development of hepatitis [5], [9].