Circulating CD133+VEGFR2+ and CD34+VEGFR2+ cells and arterial function in patients with beta-thalassaemia major

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

Absence of Fas-L aggravates renal injury in acute Trypanosoma cruzi infection

Trypanosoma cruzi infection induces diverse alterations in immunocompetent cells and organs, myocarditis and congestive heart failure. However, the physiological network of disturbances imposed by the infection has not been addressed thoroughly. Regarding myocarditis induced by the infection, we observed in our previous work that Fas-L-/- mice (gld/gld) have very mild inflammatory infiltration when compared to BALB/c mice. However, all mice from both lineages die in the early acute phase. Therefore, in this work we studied the physiological connection relating arterial pressure, renal function/damage and cardiac insufficiency as causes of death. Our results show that a broader set of dysfunctions that could be classified as a cardio/anaemic/renal syndrome is more likely responsible for cardiac failure and death in both lineages. However, gld/gld mice had very early glomerular deposition of IgM and a more intense renal inflammatory response with reduced renal filtration, which is probably responsible for the premature death in the absence of significant myocarditis in gld/gld.Instituto Oswaldo Cruz-Fiocruz Laboratório de Biologia CelularUniversidade Federal do Rio de Janeiro Instituto de Biofísica Carlos Chagas FilhoUniversidade Federal Fluminense Instituto Biomédico Departamento de Fisiologia e FarmacologiaUniversidade Federal de São Paulo (UNIFESP) Escola Paulista de Medicina Disciplina de NefrologiaCentro de Criação de Animais de Laboratório Departamento de Controle de Qualidade AnimalUNIFESP, EPM, Disciplina de NefrologiaSciEL