الفهرس 
Beta thalassemiaOnly 14 pages are availabe for public view
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Abstract
Beta-thalassemia is an inherited chronic hemolytic anemia resulting from absent or low level of synthesis of β-globin chains of HbA in erythropoietic cells. The clinical manifestations of β-thalassemia are extremely varied, spanning a broad spectrum from the transfusion-dependent state of β-thalassemia major to the asymptomatic state of thalassemia trait.
The excess α-globin tetramer formation and interaction with the red cell membrane led to hemolytic anemia and hyperplasia of erythroid precursors. Other mechanisms have been reported to be responsible for red cell lysis besides this mechanism, and to aggravate the hemolysis in β-thalassemia patients. The complement system is an important part of innate immune response that may be implicated in red blood cells lysis.
Normal cell membranes express complement regulatory proteins that regulate activation of the complement system and provide essential protection against self-damage. Many studies show that CrPs may play an important role in protecting RBC from destruction through the activation of complement. CD55 and CD35 proteins on the cell surfaces block complement activation. Loss of these proteins makes the blood cell susceptible to hemolysis.
The aim of this study was to evaluate the level of CD55 and CD35 expression on red blood cells of β-thalassemia patients and their impact on the pathogenesis of hemolysis.
This study was conducted on 100 subjects who were divided into two groups: group I:(B-thalassemia major) included 50 patients. group II:(control group) included 50 age and gender matched apparently healthy subjects.
Summary
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All patient and controls included in this study were subjected to the followings: history taking, clinical examination, laboratory investigation included: Complete blood count, reticulocytes count, serum lactate dehydrogenase (LDH), indirect bilirubin, ferritin, and assessment of the expression levels of CD55 and CD35 by flow cytometry.
Data analysis revealed that Hb concentration, RBCs count, Hct%, MCV, and MCH were significantly decreased in thalassemic group in comparison with control group. Additionally, TLC and platelets counts were significantly increased in thalassemic group in comparison with control group.
Markers of hemolysis (LDH, reticulocytes %, total bilirubin, indirect bilirubin, and ferritin) were significantly increased in thalassemic group in comparison with control group.
CD55 and CD35 expression on erythrocytes were significantly reduced in thalassemia patients as compared to control group.
Correlation analysis revealed significant positive correlation between CD55% expression and Hb concentration, RBC count, and Hct%. However, significant negative correlation was demonstrated between CD55%, and MCV and LDH.
Statistically significant positive correlation was observed between CD35% expression and Hb concentration. Moreover, significant negative correlation was found between CD35% and normoblast%, reticulocyte % and HbF%.