SYNTHESIS OF EICOSANOIDS BY PROPIONIBACTERIUM-ACNES-ELICITED LIVER ADHERENT CELLS AND THEIR EFFECT ON PRODUCTION OF INTERLEUKIN-1 AND TUMOR-NECROSIS-FACTOR

When heat-killed Propionibacterium acnes (P. acnes) is intravenously injected into rats or mice, liver adherent cells including macrophages and Kupffer cells increase in number and they synthesize various kinds of biologically-active materials. We studied the production of eicosanoids and the cytokines, interleukin 1 (IL-1) and tumor necrosis factor (TNF), by P. acnes-elicited liver adherent cells and the regulatory mechanisms of eicosanoids in the synthesis of cytokines. As a result, P. acnes-elicited liver adherent cells synthesized not only prostaglandin (PG) E2, 6-keto-PGF1α, thromboxane B2 and leukotriene B4, but also IL-1 and TNF. In addition, PGE2 and PGI2 suppressed the production of these cytokines. These results suggested that there are auto-regulatory mechanisms in production of cytokines in the liver. © 1990.