Ⅱ型遗传性出血性毛细血管扩张症血管生长发育相关蛋白质分析及意义

Analysis of angiogenesis related proteins and its implication in type-2 hereditary hemorrhagic telangiectasia

目的分析和检测1个Ⅱ型遗传性出血性毛细血管扩张症(HHT-2)家系成员血浆及外周血白细胞转化生长因子(TGF)-β1、TGF-β2、血管内皮生长因子(VFGF)、血小板源性生长因子受体α(PDGFRα)等蛋白质浓度,探讨这些血管生长发育相关蛋白在 HHT 发病机制中的变化及意义。方法根据鼻出血、毛细血管扩张及家族史进行 HHT 的临床诊断,并经基因筛查,以证实 HHT 的诊断。对该家系中5例新成员进行 HHT 的诊断和排除诊断。用 ELSA 方法检测该家系成员血浆 TGF-β1、TGF-β2及 VEGF 浓度;用流式细胞术结合直接按或间接免疫荧比技术分析该家系成员外周血白细胞TGF-β1、VEGF、及 PDGFRα蛋白表达。结果基因筛查的5例新家系成员 ALK1基因8号外显子不存在 C1231T 突变。该家系成员中3例 HHT 患者血浆 TGF-β1和 TGF-β2浓度分别为(16 954±3 709)ng/L和(11 548±2 611)ng/L;与正常对照相比差异无统计学意义(P>0.05);3例 HHT 患者、6名未受累家系成员、6名正常对照血浆 VEGF 浓度值分别为(179.2±22.0)μg/L,(149.8±22.7)μg/L,(132.9±21.0)μg/L;HHT 患告血浆 VEGF 浓度明显高于正常对照组(P<0.05)。HHT 家系成员外周血白细胞 PDGFRα和 VEGF 蛋白表达均上调(P 值均<0.05);TGF-β1蛋白表达与正常对照比较差异无统计学意义。结论 HHT-2患者血浆 TGF-β1浓度、单核细胞及粒细胞 TGF-β1蛋白表达与正常对照比较差异无统计学意义;而血浆 VEGF 浓度及外周血白细胞 VEGF 表达均明显高于正常对照;HHT-2患者外周血白细胞存在 PDGFRα高表达,提示存在血管生长发育相关蛋白的代偿机制。

Objective To detect the level of transforming growth factor-β1 （TGF-β1）, TGF-β2, vascular endothelial growth factor （VEGF） and platelet-derived growth factor receptor-α （PDGFRα）in plasma and peripheral blood leukocytes in a hereditary hemorrhagic telangiectasia type 2 （ HHT-2 ） family, and ex- plore the implication of angiogenesis related proteins in HHT-2 pathogenesis. Methods The diagnosis of the HHT-2 patient was based on clinical features and further confirmed by determining a C1231T mutation of activin receptor-like kinase 1 （ALK1） gene. Five other new members in this family were evaluated with ALK1 gene screening and clinical manifestation. Plasma level of TGF-β1, TGF-β2 or VEGF was measured by ELISA, and the expression of PDGFRα,TGF-β1, and VEGF in peripheral blood leukocytes by flow cytometry combined with direct or indirect immunofluorescence. Results No C1231T mutation was detected in exon 8 of ALK1 gene in the 5 new members . Plasma TGF-β1 and TGF-β2 concentration in 3 affected HHT case was （ 16 954 ± 3 709） ng/L and （ 11 548 ± 2 611 ） ng/L, respectively, compared with that of normal control, the difference was not significant （P 〉 0.05 ）. VEGF concentration in the 3 HHT patients, 6 unaffected family members and 6 normal controls was （ 179.2 ± 22.0） μg/L, （ 149.8 ± 22.7） μg/L and （ 132.9 ± 21.0） μg/ L, respectively. Plasma VEGF level in HHT patients was significantly higher than that in normal subjects （ P 〈 0.025 ）. Peripheral leukocyte PDGFRα and VEGF in HHT patients and unaffected family members were markedly higher than that of normal control （ P 〈 0.05 and P 〈 0.02 ）, while TGF-β1 distribution was similar in HHT patients and normal subjects. Conclusion Compared with normal controls there is no difference in plasma TGF-β1 concentration on peripheral leukocytes of HHT patients. Plasma VEGF concentration or leukocytes VEGF expression in HHT is significantly higher than that of normal subjects. Leuko- cytes PDGFRα expression in HHT is significantly higher than that of normal control. These changes may be associated with a compensable mechanism in HHT.