髓系细胞触发受体-1在输血相关性急性肺损伤大鼠肺组织的表达

Myeloid cell triggering receptor 1 expression related acute lung injury in rat lung tissue in blood transfusions

目的观察髓系细胞触发受体（TREM-1）在输血相关性急性肺损伤（TRALI）SpragueDawley（SD）大鼠肺组织中的表达及其在TRALI发病机理中的作用。方法sD大鼠55只，随机分为TRALI组（n=25）、正常对照组（n=10）和阳性对照组（n=20）。TRALI组腹腔注射脂多糖（LPS）2mg／kg2h后静脉输注人血浆（1ml／只）；正常对照组腹腔注射生理盐水2mg／kg，移除1mJ大鼠血液后及时输注等体积生理盐水；阳性对照组静脉输注LPS5mg／kg诱导急性肺损伤。3组分别于造模后6h留取外周血及肺组织，采用荧光实时定量反转录多聚酶链反应法（RT-PCR）检测大鼠外周血及肺组织TREM-1mRNA；酶联免疫吸附试验（ELISA）检测大鼠外周血及肺组织TREM-1和肿瘤坏死因子（TNF）-α浓度；HE染色进行大鼠肺组织Smith病理损伤评分。Spearman相关性分析TRALI组TREM-1mRNA、TNF-α和Smith病理损伤评分3者之间的相关性。结果TRALI组和阳性对照组大鼠肺组织TREM-1mRNA的表达（4．96±0．08、6．35±0．09）高于正常对照组（1．01±0．00）（均P〈0．05），血TREM-1mRNA的表达（9．85±3．23、12．33±3．56）也高于正常对照组（2．15±0．35）（均P〈0．05）。TRALI组大鼠肺组织和血TREM-1浓度[（695．25±116．87）、（703．80±100．67）ng／L]高于正常对照组[（234．51±44．38）、（240．22±46．63）ng／L]（均P〈0．05），但与阳性对照组差异无统计学意义（均P〉0．05）。TRALI组大鼠肺组织和血TNF-α浓度[（288．26±35．53）、（276．26±39．53）ng／L]显著高于正常对照组[（216．34±33．45）、（220．60±38．30）ng／L]（均P〈0．05），但与阳性对照组差异无统计学意义（均P〉0．05）。TRALI组Smith病理损伤评分（7．46±0．95）显著高于正常对照组（0．32±0．28）（P〈0．05），与阳性对照组（8．65±0．72）差异无统计学意义（P〉0．05）。TRALI组大鼠肺组织Smith病理损伤评分与肺组织TREM-1mRNA表达及浓度、TNF-α浓度呈正相关（r=0．377、0．489、0．763，均P〈0．05），肺组织TREM-1mRNA表达与肺组织TNF-α浓度无相关性（P〉0．05），但TREM-1浓度与TNF-α浓度正相关（r=0．689，P〈0．05）。结论TRALI大鼠肺组织中TREM-1浓度升高，与TNF-α浓度及肺损伤程度相关，提示TREM-1可能参与了TRALI肺部炎性反应。

Objective To investigate the expression of trigger receptors on myeloid cells （TREM- 1 ） in lung tissue of Sprague Dawley （SD） rats with transfusion-related acute lung injury （TRALI） and its role in the pathogenesis of TRALI. Methods Fifty-five SD rats were randomly divided into TRALI group （n= 25） , normal control group （n=10） and the positive control group （n=20）. The TRALI group was given intraperitoneal injection of 2 mg/kg lipopolysaccharide （LPS） followed by intravenous infusion of human plasma （1 murat） at 2 h later; the normal control group was intraperitoneal injection of 2 mg/kg saline, followed by intravenous infusion of 1 ml saline after withdrawal of 1 ml blood; the positive control group was given intravenously 5 mg/kg LPS to induce lung injury. At 6 h after modeling, the rats in the three groups were collected of peripheral blood and harvested for lung tissue specimens. Real-time quantitative reverse transcription polymerase chain reaction （RT- PCR） was used to detect the TREM- 1 mRNA in the rat peripheral blood and lung tissue. ELISA assay was employed to measure the levels of TREM- 1 and tumor necrosis factor （TNF）- ct in the rat peripheral blood and lung tissue. HE staining of rat lung tissue was performed for Smith pathological scoring. Spearman correlation analysis was performed to determine the correlation among TREM-1 mRNA, TNF-a and Smith pathological scores in the TRALI group. Results The expression of TREM-1 mRNA in rat lung tissue of the TRALI group （4.96±0.08） and positive control group （6.35_＋0.09） was higher than that in the control group （1.01±0.00） （all P〈0.05 ）, and so was the expression of TREM-1 mRNA in rat peripheral blood of the TRALI group （9.85 ±3.23） and positive control group （12.33±3.56） compared with the control group （2.15±0.35） Call P〈0.05）. TREM-1 concentrations in the lung tissue and blood of TRALI group [ （695.25± 116.87） and （703.80± 100.67） ng/Ll were higher than those in the control group [ （234.51±44.38） and （240.22±46.63） ng/L] （all P〈0.05） , but were not statistically different from those in the positive control group （P〉0.05）. TNF-α concentrations in the lung tissue and blood of TRALI group [ （288.26±35.53） and （276.26±39.53） ng/L] were higher than those in the control group [ （216.34±33.45） and （220.60±38.30） ng/L] （all P〈0.05）, but were not statistically different from those in the positive control group （P〉0.05）. The Smith pathological score in the TRALI group （7.46±0.95） was significantly higher than that in the control group （0.32±0.28） （P〈0.05）, but was not statistically different from that in the positive control group （8.65_＋0.72） （P〉0.05）. In the TRALI group, Smith pathological score was positively correlated with TREM-1 mRNA expression （r=0.377）, TREM-1 （r= 0.489） and TNF-α （r=0.763） concentrations in rat lung tissue （all P〈0.05） ; lung tissue TREM- 1 concentration （r=0.689, P〈0.05）, but not TREM-1 mRNA expression, was correlated with lung tissue TNF- a concentration. Conclusion TREM- 1 concentration is elevated in lung tissue of rats with TRALI and correlated with lung TNF-α level and severity of lung injury, suggesting that TREM-1 may be involved in the inflammatory response in lung TRALI.