Diverse Enhancement of Superoxide Production from Kupffer Cells and Neutrophils after Burn Injury or Septicemia

Abstract

Objective: To investigate the difference in superoxide production from circulating neutrophils and Kupffer cells between in the mice after burn injury and mice suffering from bacterial septicemia. Background: Both severe burn injury and septicemia can result in a critical/fatal outcome for the patients even after initial resuscitation. Analyses of defense mechanisms in the host who survive after severe stress are thereby very important for improvement of intensive care. Method: Either burn injury or inoculations with Peudomonas aeruginosa were subjected to C57BL/6 mice. After 7 days, circulating neutrophils and Kupffer cells were obtained from the mice to examine superoxide or cytokine production. Results: Neither of the mouse groups showed any pathological changes in major organs or any elevations in the serum transaminase or TNF levels at 7 days after burn injury or bacterial inoculation. The burn injured mice showed significantly higher superoxide production from neutrophils by stimulation with phorbor myristate acetate (PMA) or opsonized zymosan (OZ) than that from Kupffer cells. In contrast, the bacterial challenged mice showed a significantly higher superoxide production from Kupffer cells than that from neutrophils. In addition, the burn injured mice showed a significantly higher production of IL-10, namely anti-inflammatory cytokine, from the Kupffer cells by LPS stimulation than the bacterial challenged mice while the bacterial challenged mice showed a significantly higher production of IL-12, namely proinflammatory cytokine, from Kupffer cells by LPS stimulation than the burn injured mice. Conclusions: Neutrophils might thus be activated to a greater degree than Kupffer cells in mice after burn injury, while Kupffer cells might be activated more than neutrophils after bacterial septicemia.