中性 IgG2 与阴离子 IgG4 在 PD 中的转运：对电动模型的影响。

Transport of neutral IgG2 versus anionic IgG4 in PD: implications on the electrokinetic model.

机构信息

Nephrology Division, Ghent University Hospital, C. Heymanslaan 10, 9000, Ghent, Belgium.

出版信息

BMC Nephrol. 2018 Oct 29;19(1):299. doi: 10.1186/s12882-018-1104-1.

DOI:10.1186/s12882-018-1104-1

PMID:30373553

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC6206679/

Abstract

BACKGROUND

It is debated whether transperitoneal membrane transport of larger (charged) molecules in peritoneal dialysis can be partially governed by the electrokinetic model. In this model, it is postulated that streaming potentials are generated across the capillary wall by forced filtration of an ionic solution, for example transcapillary ultrafiltration induced by osmotic forces as in peritoneal dialysis. We investigated the presence of streaming potentials in the process of transperitoneal transport in Peritoneal Dialysis (PD) patients by measuring ratios of dialysate concentrations of IgG2 (neutral) and IgG4 (negative), both 150kD, under different conditions of transcapillary ultrafiltration.

METHODS

Adult PD patients randomly got two consecutive dwells of 120 min each, with either 2 L Physioneal 1.36% or 3.86% glucose dialysis fluid (Baxter, USA) as their first dwell. A blood sample was taken at the test start, and dialysate samples were taken at 5, 15, 30, 60 and 120 min. IgG2 and IgG4 concentrations were measured (ELISA) and ratios calculated.

RESULTS

In 10 patients (65 ± 17 years, 20 ± 17 months on dialysis), drained volume after 120 min was different between the 1.36% (1950 [1910; 2020] mL) and 3.86% (2540 [2380; 2800] mL) glucose dwells (P = 0.007). At none of the time points and irrespective of glucose concentration, a significant difference was found between the IgG2/IgG4 ratios at any time point.

CONCLUSION

Our data failed to demonstrate a difference in the transport ratios of two macromolecules with same molecular weight but different charge, as would be expected by the electrokinetic model, and this despite sufficient differences in transcapillary ultrafiltration.

CLINICAL TRIAL REGISTRY

Belgian Registration Number B670201523397 (20/1/2015); prospective randomized trial.

摘要

背景

腹膜透析中更大（带电荷）分子的腹膜转运是否部分受电动模型控制存在争议。在该模型中，假设跨毛细血管壁的流动电势是由离子溶液的强制过滤产生的，例如，在腹膜透析中，渗透压引起的跨毛细血管超滤会产生跨毛细血管超滤。我们通过测量不同跨毛细血管超滤条件下 IgG2（中性）和 IgG4（阴性）两种 150kD 分子的透析液浓度比来研究 IgG2（中性）和 IgG4（阴性）两种 150kD 分子在腹膜透析患者腹膜转运过程中是否存在流动电势。

方法

成人 PD 患者随机接受两次各 120 分钟的保留治疗，第一次保留治疗分别使用 2L 生理盐 1.36%或 3.86%葡萄糖透析液（美国百特）。在试验开始时抽取血样，在 5、15、30、60 和 120 分钟时抽取透析液样本。用 ELISA 法测量 IgG2 和 IgG4 浓度并计算比值。

结果

在 10 名患者（65±17 岁，透析 20±17 个月）中，1.36%（1950[1910；2020]ml）和 3.86%（2540[2380；2800]ml）葡萄糖治疗后的引流体积在 120 分钟时不同（P=0.007）。在任何时间点，无论葡萄糖浓度如何，两种电荷不同但分子量相同的大分子在任何时间点的 IgG2/IgG4 比值均无显著差异。