HbH and HbH-constant spring (HbH-CS) are the most common forms of α-
thalassemia detected in the Thai population. The accumulation of excess β
globin chains in these diseases results in increased red cell
hemolysis, and patients with HbH-CS normally have a more severe clinical presentation than patients with HbH disease. This study aimed to detect alterations in the expression of
plasma proteins of HbH and HbH-CS patients as compared to normal plasma. Platelet poor plasma was separated from HbH and HbH-CS and normal subjects and differential
plasma proteins were detected using two-dimensional gel electrophoresis and identified using LC/MS/MS. A total of 14 differentially expressed
proteins were detected of which 5
proteins were upregulated and 9 were downregulated. Most of the differentially expressed
proteins are liver secreted
proteins involved in
hemolysis, oxidative stress response, and
hemoglobin degradation. Seven
proteins were found to be differentially expressed between HbH and HbH-CS. Levels of
haptoglobin, a
hemoglobin scavenging
protein, were significantly increased in HbH patients as compared to HbH-CS patients. The identification of differentially expressed
proteins may lead to a better understanding of the biological events underlying the clinical presentation of HbH and HbH-CS patients and can have application as hemolytic markers or severity predictors.