The role of endothelial cell derived toll-like receptor 4 acute lung injury / 中华急诊医学杂志

ABSTRACT

Objective To investigate the role of toll-like receptor 4 (TLR4) of endothelium or bone marrow derived cells in the acute lung injury (ALI) induced by lipopolyscccharide (LPS) in mice with reciprocal bone marrow transplantation. Method Chimeric mice were produced by reciprocal bone marrow transplantation between TLR4mut/mut and TLR4+/+ mice and divided into 4 groups WT/WT (recipient/donor),WT/Mutant, Mutant/WT and Mutant/Mutant group. Six to eight weeks following transplantation, LPS was injected inot mice's tail vein in order to produce ALI model,and mice were sacrificed five hours later on.Samples of lung tissues were taken for the following analysis of wet/dry weight (W/D), lung permeabifity index (LPI), myeloperoxidase (MPO),levels of cytokines (TNF-α, IL-1β) and adhesion molecules (ICAM-1). Results Lung injury in the Mutant/Mutant mice was the mildest in the 4 groups. And lung injury in WT/Mutant mice was more serious than that in Mutant/WT mice. levels of MPO and ICAM-1 in WT/Mutant mice were much higher than those of Mutant/WT. In addition,the expression of ICAM-1 in WT/Mutant mice is comarable to that in WT/WT mice. Mutant/WT mice expressed higher levels of TNF-α and IL-1β than WT/Mutant mice. Conclusions Endothelial cell derived TLR4 plays ker-nel role in ALI induced by LPS via lung PMN recruitment,although bone marrow cells derived TLR4 are more im-portant for the release of cytokines.