Impact of hydroxyurea on lymphocyte subsets in children with sickle cell anemia.

BACKGROUND: Hydroxyurea (HU) has beneficial effects in the management of sickle cell anemia (SCA), but there is a paucity of data on the effect of HU on immune cells in SCA. Herein we aimed to evaluate the effect of HU on immune profiles of Egyptian children with SCA. METHODS: This was a controlled prospective cohort study conducted in 30 children with SCA and 30 healthy age-matched controls. Flow cytometry was used to evaluate lymphocyte profiles, including CD8+ T, CD19+ B, CD3+, CD4+, natural killer (NK), NK T, T helper 1 (Th1), Th2, T cytotoxic (Tc1), and Tc2 cells, prior to and after 1 year of treatment with HU. RESULTS: HU treatment led to significant increases in hemoglobin (Hb), red blood cell, and hematocrit counts and a significant decrease in the percentage of sickle Hb, with subsequent improvement in SCA complications. Compared with baseline values, CD3+, CD4+, Th1, and CD8+ T cells were significantly increased, while NK, Th2, and Tc2 cells were significantly decreased, with a resulting increase in the Th1/Th2 and Tc1/Tc2 ratios. CONCLUSIONS: HU has the beneficial effect of restoring the abnormally elevated immune parameters in children with SCA. IMPACT: Hydroxyurea treatment restores the abnormal immune parameters in children with sickle cell anemia. HU treatment led to significantly increased CD3+, CD4+, Th1, and CD8+ T cells, while NK, Th2, and Tc2 cells were significantly decreased, with a resulting increase in the Th1/Th2 and Tc1/Tc2 ratios. Our study showed the impact of HU therapy on immune parameters in children with SCA.

Circulating Endothelial Cells, Circulating Endothelial Progenitor Cells, and Circulating Microparticles in Type 1 Diabetes Mellitus.

BACKGROUND AND AIM:: Hyperglycemia in type 1 diabetes (T1D) is accompanied by endothelial cell dysfunction which is known to contribute to the pathogenesis of cardiovascular disorders. The aim of the current study was to explore the profile of circulating endothelial progenitor cells (EPCs), circulating endothelial cells (CECs), endothelial and platelet derived micropaticles (EMPs, PMPs) and total microparticles (TMPs), in T1D children in relation to each other and to the metabolic disorders accompanying T1D. PATIENTS AND METHODS:: Thirty T1D patients and 20 age and sex matched healthy volunteers were assessed for HbA1c level and lipid profile. Quantification of CECs, EPCs, TMPs, EMPs and PMPs was done by flow cytometry. RESULTS:: The mean levels of EMPs, PMPs, TMPs and CECs were significantly higher in diabetic children compared to controls. Meanwhile, the levels of EPCs were significantly lower in diabetic children compared to controls. Both PMPs and CECs showed the highest significant differences between patients and controls and their levels were directly related to HbA1c, total cholesterol, LDL and triglycerides. A moderate correlation was observed between the frequency of PMPs and CECs. EPCs revealed negative correlations with both LDL and triglycerides. TMPs were only related to LDL, while EMPs were only related to HbA1c. CONCLUSION:: Although there is disturbance in the levels of EMPs, PMPs, TMPs, CECs and EPCs in type 1 diabetic children compared to the controls, only the levels of PMPs and CECs were closely affected by the poor glycemic control and dyslipidemia occurring in T1D; thus may contribute to a higher risk of cardiovascular diseases.