Phosphatidylserine-exposed red blood cells and ineffective erythropoiesis biomarkers in patients with thalassemia

Objective: The degree of ineffective erythropoiesis is known to be associated with clinical severity among individuals with thalassemia. The association of ineffective erythropoiesis biomarker levels with different thalas-semia genotypes, however, remains limited. The aim of this study was to explore the level of phosphatidylserine-exposed red blood cells (PS-exposed RBCs) and ineffective erythropoiesis biomarkers (growth-differentiation fac-tor-15 and soluble transferrin receptors) in patients with different genotypes. Methods: A cross-sectional study was conducted on 139 patients of age 18 years and above with different genotypes at Srinagarind Hospital, Khon Kaen University, Thailand. The levels of PS-exposed RBCs were determined using flow cytometry. Measurements of growth-differentiation factor-15 (GDF-15) and soluble transferrin receptors (sTfR) were evaluated by the ELISA meth-od. Results: The PS-exposed RBCs levels were found to be significantly higher in splenectomized beta-thalassemia patients. Patients with beta-thalassemia had the highest GDF-15 levels, followed by patients with non-deletional alpha-thalassemia. Patients with non-deletional alpha-thalassemia showed elevated hemoglobin levels and re-duced GDF-15 levels after splenectomy. Patients with beta-thalassemia and non-deletional alpha-thalassemia had the highest levels of PS-exposed RBCs and ineffective erythropoiesis biomarkers, which correlated with the clinical severity of thalassemia. Conclusions: The levels of ineffective erythropoiesis biomarkers were different across thal-assemia genotypes. Splenectomy may improve clinical symptoms of patients with non-deletional alpha thalassemia but not of patients with beta-thalassemia. These findings demonstrate differences in the degree of ineffective erythropoiesis in thalassemia, which emphasizes the need for different treatment approaches among patients with different thalassemia genotypes.