体外循环后单核细胞向保护性血红蛋白清除表型（CD14（+）CD163（高）HLA-DR（低））的表型定型。

Phenotypic commitment of monocytes towards a protective hemoglobin scavenging phenotype (CD14(pos)CD163(high)HLA-DR(low))following cardiopulmonary bypass.

机构信息

Edmund Cohen Laboratory for Vascular Research, Chronic Disease Research Centre, Tropical Medicine Research Institute, University of the West Indies, Barbados.

出版信息

Cytometry B Clin Cytom. 2010 Sep;78(5):357-60. doi: 10.1002/cyto.b.20524.

DOI:10.1002/cyto.b.20524

PMID:20533393

Abstract

BACKGROUND

Intravascular hemolysis may cause tissue injury directly or via a systemic inﬂammatory response. Under physiological conditions, extracorpuscular hemoglobin (Hb) is bound by haptoglobin(Hp) and the complex internalized via the hemoglobin scavenger receptor CD163 on monocytes, prior to catabolism via heme-oxygenase-1 (HO-1). Recently, a novel subset of CD68(pos)CD163(high)HLA-DR(low) macrophages with high expression of HO-1 was recognized in hemorrhagic areas of atherosclerotic plaques, distinct from CD68(pos)CD163(low)HLA-DR(high) foam cell macrophages with low- HO-1 content. Considering the hemolytic insult during CPB, we hypothesized that an equivalent compensatory CD163(high)HLA-DR(low) phenotype will evolve in circulating CD14(pos) monocytes post surgery.

METHODS

Twelve patients undergoing elective surgery with CPB were enrolled with informed consent.Whole-blood samples were collected in EDTA at predetermined time-points, pre- intra-, and postoperatively. Whole-blood was evaluated by three-color flow cytometry for expression of CD14, CD163, and HLA-DR; CD14(pos) cells were also permeabilized to detect intracellular HO-1 protein. Plasma [Hp-Hb] concentration was determined by ELISA.

RESULTS

A striking phenotypic switch from CD163(low)HLA-DR(high) preoperatively to CD163(high)HLA-DR(low) postoperatively at 24 h was observed on circulating CD14(pos) monocytes. Intracellular HO-1 protein was also significantly up-regulated at 24 h after declamping. These phenotypic changes were preceded by peak Hb-Hp levels observed at 2 h.

CONCLUSION

We have shown for the first time, a phenotypic commitment of monocytes towards a protective CD14(pos)CD163(high)HLA-DR(low) population with increased intracellular HO-1 occurring in the circulation during the recovery phase of CPB. These findings have implications for monitoring of anti-inflammatory interventions and linkage to clinical outcomes.

摘要

背景

血管内溶血可直接或通过全身炎症反应导致组织损伤。在生理条件下，细胞外血红蛋白（Hb）与触珠蛋白（Hp）结合，并通过单核细胞上的血红蛋白清除受体 CD163 内化，然后通过血红素加氧酶-1（HO-1）进行分解代谢。最近，在动脉粥样硬化斑块的出血区域中发现了一种新型的 CD68（pos）CD163（高）HLA-DR（低）巨噬细胞亚群，其具有高表达的 HO-1，与 CD68（pos）CD163（低）HLA-DR（高）泡沫细胞巨噬细胞不同，后者的 HO-1 含量较低。考虑到 CPB 期间的溶血损伤，我们假设在手术后循环 CD14（pos）单核细胞中会出现等效的代偿性 CD163（高）HLA-DR（低）表型。

方法

本研究共纳入了 12 例接受 CPB 择期手术的患者，并获得了知情同意。在预定的时间点采集 EDTA 全血样本，包括术前、术中、术后。通过三色流式细胞术评估全血中 CD14、CD163 和 HLA-DR 的表达；还对 CD14（pos）细胞进行透化以检测细胞内 HO-1 蛋白。通过 ELISA 测定血浆 [Hp-Hb]浓度。