Pereira B J, Sundaram S, Barrett T W, Butt N K, Porat R, King A J, Dinarello C A
Department of Medicine, New England Medical Center Hospitals, Boston, Massachusetts, USA.
Clin Nephrol. 1996 Dec;46(6):394-401.
Cytokine production by peripheral blood mononuclear cells (PBMC) is a sensitive indicator of cytokine-inducing substances which may cross from contaminated dialysate into the blood compartment. The objective of this study was to compare the transfer of cytokine-inducing substances from dialysate contaminated with a culture filtrate from Pseudomonas aeruginosa across dialyzers with low (hemophan) or intermediate ultrafiltration coefficients (modified cellulose triacetate, CTA), under conditions where either 10% plasma or whole blood was circulated in the blood compartment. Eight paired experiments of in vitro dialysis were carried out at 37 degrees C using a countercurrent recirculating loop dialysis circuit with either a new CTA or hemophan dialyzer. 10% plasma in standard tissue culture medium was circulated through the blood compartment and bicarbonate dialysate was circulated in the dialysate compartment. The dialysate was challenged sequentially by log-fold dilutions (10(2), 10(3) or 10(4)) of a Ps. aeruginosa culture filtrate. Samples were drawn from the blood compartment 5 and 15 minutes after each challenge and incubated with suspensions of PBMC in the absence or presence of polymyxin B, in order to block endotoxin. After 24 h at 37 degrees C, total interleukin-1 alpha (IL-1 alpha) was measured by RIA. Although the dialysate contained potent cytokine-inducing substances, there was no significant IL-1 alpha production by PBMC incubated with the plasma mixture from the blood compartment in the majority of experiments with both dialyzers and with each of the three dilutions of the bacterial challenge. Eight experiments were also performed with CTA dialzyers using heparinized whole blood in the blood compartment. Samples of whole blood and dialysate were drawn at baseline, after one hour of dialysis with uncontaminated dialysate and 15 minutes and three hours after dialysis with dialysate contaminated with Ps. aeruginosa filtrate. There was no significant IL-1 alpha production by PBMC isolated from the whole blood 1 h after dialysis with uncontaminated dialysate, and 15 min and 2 h after adding the Ps. aeruginosa filtrate to the dialysate side. In contrast, production of IL-1 alpha by PBMC from the same donors incubated with samples from the dialysate were 263 +/- 50, 1074 +/- 306, 2333 +/- 774 and 2602 +/- 702 pg/2.5 x 10(6) PBMC, respectively at the same four time points. These data suggest that although the Ps. aeruginosa culture filtrate present in the dialysate was a potent inducer of IL-1 alpha, neither dialyzer permitted transfer of cytokine inducing substances from the dialysate into the blood compartment.
外周血单个核细胞（PBMC）产生细胞因子是细胞因子诱导物质的敏感指标，这些物质可能会从受污染的透析液进入血液腔室。本研究的目的是比较在血液腔室中循环10%血浆或全血的条件下，被铜绿假单胞菌培养滤液污染的透析液中细胞因子诱导物质通过低超滤系数（血仿膜）或中超滤系数（改性三醋酸纤维素，CTA）透析器的转运情况。使用新的CTA或血仿膜透析器，在37℃下通过逆流循环回路透析装置进行了8对体外透析实验。标准组织培养基中的10%血浆在血液腔室中循环，碳酸氢盐透析液在透析液腔室中循环。依次用铜绿假单胞菌培养滤液的对数倍稀释液（10²、10³或10⁴）对透析液进行挑战。每次挑战后5分钟和15分钟从血液腔室中采集样本，并在不存在或存在多粘菌素B的情况下与PBMC悬液一起孵育，以阻断内毒素。在37℃下孵育24小时后，通过放射免疫分析法测定总白细胞介素-1α（IL-1α）。尽管透析液中含有有效的细胞因子诱导物质，但在大多数实验中，使用两种透析器以及细菌挑战的三种稀释液中的每一种时，与来自血液腔室的血浆混合物一起孵育的PBMC均未产生显著的IL-1α。还使用CTA透析器在血液腔室中使用肝素化全血进行了8次实验。在基线、用未受污染的透析液透析1小时后、用铜绿假单胞菌滤液污染的透析液透析15分钟和3小时后采集全血和透析液样本。在用未受污染的透析液透析1小时后以及在透析液侧加入铜绿假单胞菌滤液15分钟和2小时后，从全血中分离的PBMC均未产生显著的IL-1α。相比之下，在相同的四个时间点，与来自透析液的样本一起孵育的同一供体的PBMC产生的IL-1α分别为263±50、1074±306、2333±774和2602±702 pg/2.5×10⁶PBMC。这些数据表明，尽管透析液中存在的铜绿假单胞菌培养滤液是IL-1α的有效诱导剂，但两种透析器均未允许细胞因子诱导物质从透析液转移到血液腔室中。
