Department of Laboratory Medicine, Affiliated Hospital of Jiangsu University, Zhenjiang, PR China.
Scand J Rheumatol. 2010;39(1):26-32. doi: 10.3109/03009740903124424.
Expression of Notch homologues in local tissue inflammation in rheumatoid arthritis (RA) and cultured synoviocytes has been reported, but the expression profile of Notch-related molecules in peripheral lymphocytes in RA remains unclear. In this study, we measured the expression of Notch receptors and downstream molecules in peripheral lymphocytes from RA patients.
Expression of Notch receptors in peripheral lymphocytes of RA patients was assessed by both flow cytometry and real-time polymerase chain reaction (PCR). Expression of the representative Notch target gene HES-1 and the regulatory gene NUMB in purified T helper cells from RA patients was determined by real-time PCR, and expression of Notch intracellular domain (ICD) was determined by immunoblot analysis.
There was an increased expression of Notch 2, Notch 3, and Notch 4 in T helper cells from active RA patients, among which increased expression of Notch 3 was mainly by activated T cells. Notably, expression of Notch 3 in T cells decreased in inactive RA patients and the level was similar to that of healthy controls (HC). Notch receptors were rarely observed on B cells and no difference in expression was found between RA patients and HC. T helper cells from RA patients exhibited increased expression of the target gene HES-1 but decreased expression of the negative modulation gene NUMB of Notch signalling. There was also an increased nuclear translocation of Notch-ICD in T helper cells from active RA disease.
The present study demonstrated that T helper cells from RA patients display a significantly altered expression profile of Notch receptors and enhanced activation of Notch signalling compared with HC.
已有研究报道，类风湿关节炎（RA）局部组织炎症和培养的滑膜细胞中 Notch 同源物的表达情况，但 RA 患者外周血淋巴细胞中 Notch 相关分子的表达谱尚不清楚。本研究旨在检测 RA 患者外周血淋巴细胞中 Notch 受体及其下游分子的表达情况。
采用流式细胞术和实时聚合酶链反应（PCR）检测 RA 患者外周血淋巴细胞中 Notch 受体的表达。采用实时 PCR 检测 RA 患者辅助性 T 细胞中代表性 Notch 靶基因 HES-1 和调节基因 NUMB 的表达，免疫印迹分析 Notch 细胞内结构域（ICD）的表达。
与健康对照（HC）相比，活性 RA 患者辅助性 T 细胞中 Notch2、Notch3 和 Notch4 的表达增加，其中 Notch3 的表达增加主要由活化的 T 细胞引起。值得注意的是，在缓解期 RA 患者中 Notch3 的表达减少，其水平与 HC 相似。B 细胞中 Notch 受体表达较少，RA 患者与 HC 之间无差异。RA 患者辅助性 T 细胞中靶基因 HES-1 的表达增加，而 Notch 信号通路的负调节基因 NUMB 的表达减少。活性 RA 患者的辅助性 T 细胞中 Notch-ICD 的核转位也增加。
本研究表明，与 HC 相比，RA 患者的辅助性 T 细胞中 Notch 受体的表达谱明显改变， Notch 信号通路的激活增强。
