title: Circulating CD133(+)VEGFR2          (+) and CD34          (+)VEGFR2          (+) cells and arterial function in patients with beta-thalassaemia major.
abstract: Arterial dysfunction has been documented in patients with beta-thalassaemia major. This study aimed to determine the quantity and proliferative capacity of circulating CD133(+)VEGFR2(+) and CD34(+)VEGFR2(+) cells in patients with beta-thalassaemia major and those after haematopoietic stem cell transplantation (HSCT), and their relationships with arterial function. Brachial arterial flow-mediated dilation (FMD), carotid arterial stiffness, the quantity of these circulating cells and their number of colony-forming units (CFUs) were determined in 17 transfusion-dependent thalassaemia patients, 14 patients after HSCT and 11 controls. Compared with controls, both patient groups had significantly lower FMD and greater arterial stiffness. Despite having increased CD133(+)VEGFR2(+) and CD34(+)VEGFR2(+) cells, transfusion-dependent patients had significantly reduced CFUs compared with controls (p = 0.002). There was a trend of increasing CFUs across the three groups with decreasing iron load (p = 0.011). The CFUs correlated with brachial FMD (p = 0.029) and arterial stiffness (p = 0.02), but not with serum ferritin level. Multiple linear regression showed that CFU was a significant determinant of FMD (p = 0.043) and arterial stiffness (p = 0.02) after adjustment of age, sex, body mass index, blood pressure and serum ferritin level. In conclusion, arterial dysfunction found in patients with beta-thalassaemia major before and after HSCT may be related to impaired proliferation of CD133(+)VEGFR2(+) and CD34(+)VEGFR2(+) cells.
authors.affiliation: Division of Paediatric Cardiology, Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, The University of Hong Kong, Hong Kong, China. xfcheung@hkucc.hku.hk
authors.forename: Yiu-Fai
authors.initials: YF
authors.lastname: Cheung
authors.forename: Shing
authors.initials: S
authors.lastname: Chan
authors.forename: Mo
authors.initials: M
authors.lastname: Yang
authors.forename: Jie-Yu
authors.initials: JY
authors.lastname: Ye
authors.forename: Shau-Yin
authors.initials: SY
authors.lastname: Ha
authors.forename: Sophia J
authors.initials: SJ
authors.lastname: Wong
authors.forename: Godfrey Chi-Fung
authors.initials: GC
authors.lastname: Chan
mesh_terms: D000071916:AC133 Antigen; D000293:Adolescent; D000328:Adult; D015703:Antigens, CD / Q000276:immunology*; D018952:Antigens, CD34 / Q000276:immunology*; D001158:Arteries / Q000502:physiology* / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006023:Glycoproteins / Q000276:immunology*; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D007223:Infant; D008297:Male; D010455:Peptides / Q000276:immunology*; D040301:Vascular Endothelial Growth Factor Receptor-2 / Q000276:immunology*; D055815:Young Adult; D017086:beta-Thalassemia / Q000276:immunology / Q000503:physiopathology* / Q000601:surgery
chemical_list: D000071916:AC133 Antigen; D015703:Antigens, CD; D018952:Antigens, CD34; D006023:Glycoproteins; C000606023:PROM1 protein, human; D010455:Peptides; D040301:Vascular Endothelial Growth Factor Receptor-2