免疫相关性全血细胞减少症部分病例中有核红细胞上的促红细胞生成素受体及IgG自身抗体表达

Erythropoietin Receptors and IgG Autoantibody Expression on Nucleated Erythrocytes in Some Cases of Immuno-Related Pancytopenia.

作者信息

Liu Hui, Fu Rong, Li Lijuan, Ding Kai, Wang Yihao, Wang Honglei, Zhang Tian, Wang Guojin, Song Jia, Shao Zonghong

出版信息

Clin Lab. 2015;61(7):693-8. doi: 10.7754/clin.lab.2014.141227.

DOI:10.7754/clin.lab.2014.141227

PMID:26299067

Abstract

BACKGROUND

In recent years, we have detected autoantibodies in bone marrow (BM) hemopoietic cells in some patients with idiopathic cytopenia of undetermined significance (ICUS), termed immunorelated pancytopenia (IRP). However, we know little about the targets of these autoantibodies.

METHODS

Twenty-six newly diagnosed IRP patients with IgG autoantibody on nucleated erythrocytes and 20 healthy donors as controls were enrolled in this study. The serum erythropoietin (EPO) level was examined by ELISA. Expression of EPO receptor (EPOR) and IgG autoantibody on the membrane of nucleated erythrocytes were detected by flow cytometry before and after autoantibody stripping.

RESULTS

The serum EPO level of the untreated patients was 199.9 ± 106.4 mIU/mL, which was significantly higher than that of normal controls (13.2 ± 8.41 mIU/mL, p < 0.01). EPOR expression on nucleated erythrocytes in the patients was 1.38 ± 0.73%, lower than that of normal controls (2.33 ± 1.73%), but there was no significant difference; EPOR in these patients was inversely correlated with IgG autoantibody on erythrocytes (r = -0.479, p = 0.013). The regression equation was Y = 0.116-0.479X; EPOR expression on the membrane increased significiantly (5.63 ± 4.99%, p < 0.01) after stripping the autoantibodies. After immunosuppressive treatment, median hemoglobin increased from 72 g/L to 98 g/L, and median reticulocytes increased from 1.46% to 3.56%.

CONCLUSIONS

IgG autoantibodies might block or competitively inhibit EPOR on nucleated erythrocytes in some cases of ICUS.

摘要

背景

近年来，我们在一些意义未明的特发性血细胞减少症（ICUS）患者的骨髓造血细胞中检测到自身抗体，称为免疫相关性全血细胞减少症（IRP）。然而，我们对这些自身抗体的靶标了解甚少。

方法

本研究纳入了26例新诊断的有核红细胞上存在IgG自身抗体的IRP患者，并以20名健康供者作为对照。采用酶联免疫吸附测定法检测血清促红细胞生成素（EPO）水平。通过流式细胞术检测自身抗体洗脱前后有核红细胞膜上EPO受体（EPOR）和IgG自身抗体的表达。

结果

未经治疗的患者血清EPO水平为199.9±106.4 mIU/mL，显著高于正常对照（13.2±8.41 mIU/mL，p<0.01）。患者有核红细胞上的EPOR表达为1.38±0.73%，低于正常对照（2.33±1.73%），但差异无统计学意义；这些患者的EPOR与红细胞上的IgG自身抗体呈负相关（r=-0.479，p=0.013）。回归方程为Y=0.116-0.479X；洗脱自身抗体后，膜上EPOR表达显著增加（5.63±4.99%，p<0.01）。免疫抑制治疗后，血红蛋白中位数从72 g/L升至98 g/L，网织红细胞中位数从1.46%升至3.56%。