Rosenthal J, Thurman G W, Cusack N, Peterson V M, Malech H L, Ambruso D R
Department of Pediatrics, University of Colorado School of Medicine, Denver, USA.
Blood. 1996 Dec 1;88(11):4321-9.
Infection is a major cause of morbidity and mortality in patients after thermal injury. This predisposition to infections is related, in part, to abnormal polymorphonuclear leukocyte (PMN) function and a diminished respiratory burst. To evaluate the biochemical basis for the defective respiratory burst after major burns, the status of the oxidase enzyme system and its components was investigated. PMNs were isolated from 24 patients with 12% to 62% burns. Oxidase activity of intact PMNs, measured as superoxide anion (O2-) generation or oxygen consumption, was decreased in burn compared with healthy controls. Subcellular fractions from patient PMNs generated less O2- in the sodium dodecyl sulfate cell-free system, and this was related to a diminished contribution by cytosol but not by plasma membrane. Subsequently, cytosol was separated with CM-Sepharose, yielding two fractions; one contained the p47-phox and p67-phox (47/67 mix) and the other contained the remaining cytosolic components (run through [RT]). Although the contribution to oxidase activity made by RT from patient cytosol was similar to that of control, the activity of p47/67 mix from PMNs of burn patients was deficient. Quantitative assays using an immunoautoradiographic technique showed a consistent, but significant decrease in both p47-phox and p67-phox. The addition of purified or human recombinant p47-phox but not p67-phox corrected the diminished oxidase activity of cytosol from burn patients. Thus, decreased respiratory burst activity found in PMNs from individuals with thermal injury was associated with a specific, quantitative deficiency of p47-phox.
感染是热损伤患者发病和死亡的主要原因。这种易感染的倾向部分与多形核白细胞（PMN）功能异常和呼吸爆发减弱有关。为了评估大面积烧伤后呼吸爆发缺陷的生化基础，对氧化酶系统及其组成成分的状态进行了研究。从24例烧伤面积为12%至62%的患者中分离出PMN。与健康对照组相比，烧伤患者完整PMN的氧化酶活性（以超氧阴离子（O2-）生成或耗氧量来衡量）降低。患者PMN的亚细胞组分在十二烷基硫酸钠无细胞系统中产生的O2-较少，这与胞质溶胶而非质膜的贡献减少有关。随后，用CM-琼脂糖凝胶分离胞质溶胶，得到两个组分；一个含有p47-phox和p67-phox（47/67混合物），另一个含有其余的胞质成分（贯穿物[RT]）。尽管患者胞质溶胶中RT对氧化酶活性的贡献与对照组相似，但烧伤患者PMN中p47/67混合物的活性不足。使用免疫放射自显影技术的定量分析显示，p47-phox和p67-phox均持续但显著减少。添加纯化的或人重组的p47-phox而非p67-phox可纠正烧伤患者胞质溶胶氧化酶活性的降低。因此，热损伤个体的PMN中发现的呼吸爆发活性降低与p47-phox的特异性定量缺陷有关。
