Effects of Kupffer cell-depletion on Concanavalin A-induced hepatitis

TNF-α, IFN-γ, IL-4, and MIP-2 are known to be involved in Con A-induced hepatitis. Although Kupffer cells are reportedly involved in TNF-α production, it is largely unknown whether or not Kupffer cells also play a role in the production of other cytokines, such as IFN-γ, IL-4, and MIP-2. In this study we examined the liver injury and the levels of plasma cytokines, including above four cytokines, KC, and IL-10 in Kupffer cell-depleted mice obtained through administration of liposome-encapsulated dichloromethylene bisphosphonate. The liver injury was significantly suppressed in Kupffer cell-depleted mice, as assessed as to the plasma ALT level and histochemistry. The cytokine levels were also significantly suppressed in such mice except for those of IFN-γ, which was slightly suppressed at 12 h, and IL-10, which was not significantly suppressed at any time. Apoptosis was also significantly suppressed in such mice, as found immunohistochemically with anti-ssDNA Ab. Taken together, these results suggest that Kupffer cells are involved in the production of MIP-2, KC, IL-4, and TNF-α in Con A-induced hepatitis, thereby contributing to the liver injury either directly or indirectly.