中国人先天性溶血性贫血红细胞膜骨架4.1蛋白电泳变异型

目的:鉴定中国人先天性溶血性贫血(溶贫)红细胞膜4.1蛋白(band 4.1)电泳变异类型.方法:以普通显微镜、相差镜和扫描电镜观察25例溶贫患者红细胞形态学变化.以4%～15% 梯度聚丙烯酰胺凝胶电泳作红细胞膜蛋白定性定量分析.结果:(1)25例红细胞形态学异常溶贫患者中,band 4.1定性定量改变者11例(44%).(2)Band 4.1电泳变异型:①4.1a/b亚基同时缺陷;②4.1a亚基缺陷,a/b亚基相对含量比值倒置(患者0.65～1.20,正常对照1.87±0.22);③4.1a亚基部分缺失伴异常区带(相对分子质量70 000、62 000、48 000);④4.1a亚基完全缺失伴74 000异常区带.(3)除了band 4.1a完全缺失者为筛孔状红细胞形态变化以外,其他电泳变异型与细胞形态学变化无明显对应关系.结论:Band 4.1缺陷不仅可以导致红细胞椭圆形变和球形变,还可导致其他形态改变如筛孔形状.除了spectrin、band 3 以外,band 4.1缺陷是中国人遗传性球形红细胞增多症(HS)另一种常见病因,而欧美国家为ankyrin缺乏,在日本更常见band 4.2缺乏.Band 4.1a完全缺失和部分缺失伴异常区带电泳型未见于国外文献报道.结果提示,HS的主要病因和band 4.1变异型差异可能与种族不同有关.

Electrophorestic variants of erythrocyte membrane cytoskeletal protein band 4.1 in Chinese with hereditary hemolytic anemia

Objective:To identify the electrophorestic variants of band 4.1 protein(one of the cytoskeletons in erythrocyte membrane) in Chinese with hereditary hemolytic anemia (HHA). Methods:Twenty-five hemolytic anemia(HA) individuals from unrelated kindreds with abnormal red cell morphology were screened by a protocol on red cell morphology (phase contrast microscope,scanning electron microscope) and red cell membrane proteins (4%-15% sodium dodecylsulfate polyacrylamide gel electrophoresis).Results: The band 4.1 defect in quantity or quality was found in 11 patients(44%).The electrophorestic variants were divided into 4 types:band 4.1 deficiency in both a and b subunits,deficiency only in band 4.1a,partial band 4.1a deficiency,and complete band 4.1a deficiency.The variants showed no correspondence to cell morphology except the type of complete band 4.1a absence, which was only seen in the red cells with screenmes-like membrane surface.Conclusion:The band 4.1 defect is associateds not only with hereditary spherocytosis (HS) and hereditary elliptocytosis, but also with other morphologic changes.In addition to the dificiency in spectrin and band 3,another major cause of HS is the defect of band 4.1 protein in Chinese,while ankyrin in European and North American and band 4.2 more frequently in Japanese.These findings imply the causes of HS and the band 4.1 electrophrestic variants may be different among the different race.