Prostaglandin E 1 protects against liver injury induced by Escherichia coli infection via a dominant th2‐like response of liver T cells in mice

Prostaglandin E series (PGEs) are known to protect against lipopolysaccharide (LPS)‐induced liver injury by down‐regulating the production of inflammatory cytokines. We show here a novel mechanism whereby prostaglandin E 1 protects mice against liver injury after Escherichia coli infection. Prostaglandin E 1 administration suppressed circulating interleukin 12 (IL‐12) levels but increased the IL‐10 production after E. coli challenge. Furthermore, prostaglandin E 1 ‐α‐cyclodextrin (PGE 1 ) shifted the Th1/Th2 balance of CD3 intermediate IL‐2Rβ + T cells in the liver to a dominant Th2‐like response. Neutralization of endogenous IL‐4 by administration of anti–IL‐4 monoclonal antibody (mAb) diminished the inhibitory effect of prostaglandin E 1 on liver injury after E. coli challenge. These results suggested that the Th2‐like response of liver T cells may be at least partly involved in the mechanism whereby prostaglandin E 1 protects against E. coli ‐induced liver injury.