Abstract

Association of Activated Circulating Endothelial Cells with Vascular Complications in Egyptian Beta-Thalassemic Patients

Afaf Abd Elaziz Abd Elghaffar, Soha Raouf Youssef, Deena Mohamed Mohamed Habashy, Mona Ali Mohamed Hassan, Nevine Nabil Mostafa, Gihan Mohamed Kamal and Amira Nashaat Abd El-Gawad

Background: There is evidence of an association between circulating endothelial cells (CECs) and vascular complications in thalassemic patients.

Objectives: To quantify CECs and its activated fraction (AECs) in Egyptian ß-thalassemic patients and to investigate their association with incidence of vascular complications.

Subjects and Methods: Eighty pediatric patients and 30 healthy pediatric volunteers were studied for the proportion of CECs and AECs using cellular expression of endothelial adhesion receptors: CD146 and CD106 by flow cytometry.

Results: CECs, AECs were higher in patients’ group than control group (p=0.001). AECs, serum ferritin, total leucocyte count (TLC), platelet (PLT) count were higher in patients with vascular complications and splenectomized patients (p=0.001for all). Percent of AECs was positively correlated to each of serum iron (p=0.001) and serum ferritin (p=0.001). No correlation was found between AECs (percent/absolute count) or MFI of CD106 and serum ferritin neither in group with vascular complications nor in splenectomized group (p>0.05). Also, no correlation was found between red blood cell (RBC) and PLT counts neither in group with vascular complication and who underwent splenectomy, nor in those without vascular complications and did not undergo splenectomy or those who underwent splenectomy but has no vascular complications (p=0.05). Size of the AEC compartment, intensity of CD106 expression were positively correlated to each of TLC, PLT count (p=0.001 for all). Risk of vascular complications was identified if percent of ACEs was ≥58.3% of CECs, absolute count of AECs was ≥0.059 x 103 /µl, MFI of CD106 was ≥7.9, with an effectiveness of 95%, 91.3%, 95% respectively.

Conclusion: Measurement of AECs presents an effective quantitative method for assessment of risk of vascular complications in thalassemia.