Kramer B W, Jobe A H, Bachurski C J, Ikegami M
Department of Pulmonary Biology, Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039, USA.
Am J Respir Crit Care Med. 2001 Jan;163(1):158-65. doi: 10.1164/ajrccm.163.1.2005084.
We tested the effects of surfactant protein A (SP-A) on inflammation and surfactant function in ventilated preterm lungs. Preterm lambs of 131 d gestation were ventilated for 15 min to initiate a mild inflammatory response, and were then treated with 100 mg/ kg recombinant human SP-C surfactant or with the same surfactant supplemented with 3 mg/kg ovine SP-A. Addition of SP-A to the SP-C surfactant did not change lung function. After 6 h of ventilation, cell numbers in the alveolar wash were 4.9 times higher in SP-A + SP-C-surfactant-treated animals. Cellular infiltrates consisted of neutrophils that produced less hydrogen peroxide than did cells from SP-C-surfactant-treated animals. Expression of adhesion molecules CD11b and CD44 was significantly greater after SP-A treatment, whereas the expression of CD14 was unchanged. Messenger RNAs (mRNAs) for the proinflammatory cytokines interleukin (IL)-1beta, IL-6, and IL-8, but not tumor necrosis factor-alpha, were increased in SP-A-treated lungs. Surfactant protein mRNAs and protein leakage into alveolar washes were not altered by SP-A, indicating that SP-A treatment produces no evidence of lung injury. The present study identifies an unanticipated role of SP-A in neutrophil recruitment in the lungs of preterm lambs.
我们测试了表面活性蛋白A（SP-A）对机械通气早产肺炎症及表面活性功能的影响。对妊娠131天的早产羔羊进行15分钟的机械通气以引发轻度炎症反应，然后分别用100mg/kg重组人SP-C表面活性剂或添加3mg/kg羊SP-A的相同表面活性剂进行治疗。向SP-C表面活性剂中添加SP-A并未改变肺功能。通气6小时后，接受SP-A + SP-C表面活性剂治疗的动物肺泡灌洗中的细胞数量比其他组高4.9倍。细胞浸润由中性粒细胞组成，这些中性粒细胞产生的过氧化氢比接受SP-C表面活性剂治疗的动物的细胞少。SP-A治疗后，黏附分子CD11b和CD44的表达显著增加，而CD14的表达未改变。在接受SP-A治疗的肺中，促炎细胞因子白细胞介素（IL）-1β、IL-6和IL-8的信使核糖核酸（mRNA）增加，但肿瘤坏死因子-α的mRNA未增加。SP-A未改变表面活性蛋白mRNA及蛋白向肺泡灌洗液中的渗漏情况，表明SP-A治疗未产生肺损伤的迹象。本研究确定了SP-A在早产羔羊肺中性粒细胞募集过程中发挥的意外作用。
