Martin T R, Rubenfeld G D, Ruzinski J T, Goodman R B, Steinberg K P, Leturcq D J, Moriarty A M, Raghu G, Baughman R P, Hudson L D
Medical Research Service, Seattle VA Medical Center, Seattle, Washington, 98108, USA.
Am J Respir Crit Care Med. 1997 Mar;155(3):937-44. doi: 10.1164/ajrccm.155.3.9117029.
The effects of bacterial endotoxin (lipopolysaccharide, LPS) are amplified by lipopolysaccharide binding protein (LBP) and CD14, resulting in cellular activation at very low concentrations of LPS. To investigate the importance of this pathway in acute lung injury, we measured LPS, LBP, and soluble CD14 (sCD14) in the bronchoalveolar lavage fluid (BAL) of 82 patients with acute respiratory distress syndrome (ARDS). LBP and sCD14 increased markedly in BAL of patients with ARDS. sCD14 and LBP each were strongly related to BAL total protein and polymorphonuclear neutrophil (PMN) concentration, whereas LPS concentration was not. Multivariate analyses showed sCD14 to be strongly related to BAL total protein, even after controlling for LPS and LBP concentrations. sCD14 was strongly and independently related to PMN concentration, after controlling for BAL LPS, LBP, and interleukin-8 (IL-8). The BAL LPS concentration was not strongly related to either BAL total protein or BAL PMN. The BAL sCD14 and LBP values were similar in all subgroups of patients with ARDS, and were not related to survival. The serum LBP and sCD14 were elevated in ARDS, but were not related to BAL total protein, LBP, sCD14, PMN, or clinical outcome. Thus, LBP and sCD14 reach high concentrations in the lungs of patients with ARDS, and BAL sCD14 is strongly related to two major indices of lung inflammation: total protein and PMN concentration. CD14-dependent mechanisms may contribute to lung inflammation in ARDS.
细菌内毒素（脂多糖，LPS）的作用通过脂多糖结合蛋白（LBP）和CD14得以放大，从而在极低浓度的LPS下引发细胞活化。为了研究该途径在急性肺损伤中的重要性，我们检测了82例急性呼吸窘迫综合征（ARDS）患者支气管肺泡灌洗液（BAL）中的LPS、LBP和可溶性CD14（sCD14）。ARDS患者BAL中的LBP和sCD14显著升高。sCD14和LBP均与BAL总蛋白及多形核中性粒细胞（PMN）浓度密切相关，而LPS浓度则不然。多变量分析显示，即使在控制LPS和LBP浓度后，sCD14仍与BAL总蛋白密切相关。在控制BAL LPS、LBP和白细胞介素-8（IL-8）后，sCD14与PMN浓度密切且独立相关。BAL LPS浓度与BAL总蛋白或BAL PMN均无密切关系。ARDS患者所有亚组的BAL sCD14和LBP值相似，且与生存率无关。ARDS患者血清LBP和sCD14升高，但与BAL总蛋白、LBP、sCD14、PMN或临床结局无关。因此，LBP和sCD14在ARDS患者肺部达到高浓度，且BAL sCD14与肺部炎症的两个主要指标：总蛋白和PMN浓度密切相关。依赖CD14的机制可能在ARDS的肺部炎症中起作用。
