Removal of cytokine inducing substances by polymyxin-B immobilized polystyrene-derivative fibers during in vitro hemoperfusion of 10% human plasma containing Staphylococcus aureus challenge
Removal of cytokine inducing substances by polymyxin-B immobilized polystyrene-derivative fibers during in vitro hemoperfusion of 10% human plasma containing Staphylococcus aureus challenge
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DOI：
10.1097/00002480-199801000-00011
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发表时间：
1998-01-01
期刊：
影响因子：
4.2
通讯作者：
Pereira, BJG
中科院分区：
文献类型：
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作者：
Jaber, BL;Barrett, TW;Pereira, BJG
金黄色葡萄球菌(S.aureus)经常从医院的血液培养中分离出来。金黄色葡萄球菌菌血症的发病机制可能与革兰氏阴性细菌感染有关。细胞壁成分，如肽多聚糖和脂磷壁酸(LTA)，可以激发细胞因子的产生。多粘菌素-B(PMX-B)是一种结合内毒素(ET)并抑制其活性的阳离子多肽。基于这一原理，PMX-B被加入到聚苯乙烯衍生纤维中，创建了去除ET的血液灌流柱(PMX-20R)。作者评估了金黄色葡萄球菌是否具有PMX-B可抑制的细胞因子诱导物质，以及阴离子分子LTA是否为此类物质之一。取健康志愿者肝素化血液，用Ficoll-Hypaque分离法分离外周血单个核细胞(PBMC)，制备10%人血浆。PBMC分别加入1、5或10mU g/ml的金黄色葡萄球菌LTA，加或不加10mU g/mlPMX-B。同时，使用PMX-20R进行体外血液灌流(IVH)，将含有1：1000金黄色葡萄球菌攻击稀释度的10%人血浆在37℃下以100ml/min的速度作用2小时，并将IVH前后的血浆与PBMC孵育。在37℃孵育24小时后，对PBMC进行3次冻融循环，用放射免疫法测定总的肿瘤坏死因子α。对照组PBMC经LTA孵育后产生的肿瘤坏死因子α分别为164+/-4pg、324+/-54pg、657+/-55pg和1143+/-215pg，LTA分别为1、5和10mU g/ml。加入PMX-B后，肿瘤坏死因子α的产量分别下降了40+/-12%(p=0.02)、61+/-6%(p=0.002)和62+/-14%(p=0.02)。IVH前，用含金黄色葡萄球菌的10%血浆孵育的PBMC产生的肿瘤坏死因子α为1275+/-70pg。在IVH后2小时，肿瘤坏死因子α的产生下降了20+/-4%(p=0.002)。总之，金黄色葡萄球菌LTA诱导的肿瘤坏死因子α的产生被PMX-B显著抑制。因此，在PMX-20R的IVH过程中，金黄色葡萄球菌细胞因子诱导物质被清除，这可能是由于LTA与PMX-B的化学计量结合。
Staphylococcus aureus (S. aureus) is frequently isolated from blood cultures in the hospital setting. The pathogenesis of S. aureus bacteremia probably replicates mechanisms implicated in gram negative bacterial infections. Cell wall components, such as peptidoglycans and lipoteichoic acids (LTA), can trigger cytokine production. Polymyxin-B (PMX-B) is a cationic peptide that binds endotoxin (ET) and inhibits its activity. Based on this principle, PMX-B was incorporated in polystyrene-derivative fibers, creating a hemoperfusion column (PMX-20R) that removes ET. The authors assessed whether S. aureus possesses PMX-B suppressible cytokine-inducing substances, and whether LTA, an anionic molecule, is one such substance. Heparinized blood was obtained from healthy volunteers, peripheral blood mononuclear cells (PBMC) were isolated by Ficoll-Hypaque separation, and 10% human plasma prepared. PBMC were incubated with 1, 5, or 10 mu g/ml of S. aureus LTA, with and without 10 mu g/ml of PMX-B. Also, using PMX-20R, in vitro hemoperfusion (IVH) was performed with 10% human plasma containing 1:1,000 dilution of S. aureus challenge at 100 ml/min for 2 hours at 37 degrees C, and plasma obtained before and after IVH was incubated with PBMC. After a 24 hour incubation at 37 degrees C, PBMC were subjected to three freeze-thaw cycles, and total TNF alpha was measured by radioimmunoassay. TNF alpha production by PBMC incubated with LTA was 164 +/- 4 pg, 324 +/- 54 pg, 657 +/- 55 pg, and 1143 +/- 215 pg in control, and LTA 1, 5, and 10 mu g/ml, respectively. The addition of PMX-B resulted in a 40 +/- 12% (p = 0.02), 61 +/- 6% (p = 0.002), and 62 +/- 14% (p = 0.02) decrease in TNF alpha production, respectively. Before IVH, TNF alpha production by PBMC incubated with 10% plasma containing S. aureus challenge was 1275 +/- 70 pg. After 2 hours of IVH, the decrease in TNF alpha production was 20 +/- 4% (p = 0.002). In conclusion, S. aureus LTA induces TNF alpha production that is significantly suppressed by PMX-B. Consequently, S. aureus cytokine-inducing substances are removed during IVH with PMX-20R, and this may be due to stoichiometric binding of LTA to PMX-B.