Evaluation of Bak and Bcl-Xl gene expression among pediatric patients with acute primary immune thrombocytopenia.

Background: Immune thrombocytopenia (ITP) is an autoimmune disorder characterized by a low platelet counts and an increased risk of bleeding. Moreover, the apoptotic mechanisms of platelets may influence their production and lifespan.

Purpose: To assess the involvement of apoptotic markers-specifically the B-cell lymphoma protein 2 family proteins Bak and Bcl-Xl in the pathogenesis of acute primary ITP in pediatric patients, and to evaluate the impact of intravenous immunoglobulin (IVIG) therapy on their expression.

Methods: This study included 24 children with acute primary ITP and 30 healthy controls. Patients were enrolled from the Hematology and Oncology Unit of Menoufia University Hospitals, Egypt. Two peripheral blood samples were obtained from each participant: one prior to receiving IVIG therapy and the other after treatment. Platelet-rich plasma was isolated, and Bak and Bcl-Xl gene expression levels were assessed using reverse transcription quantitative polymerase chain reaction.

Results: Before treatment, Bak gene expression and Bak/Bcl-Xl expression ratio were significantly higher in patients versus controls (P=0.001 and P<0.001, respectively), whereas Bcl-Xl gene expression was significantly lower (P= 0.029). After treatment, Bak gene expression and the Bak/Bcl-Xl expression ratio decreased significantly (P<0.001 and P=0.001, respectively), whereas Bcl-Xl gene expression increased significantly (P<0.001).

Conclusion: Pediatric patients with acute primary ITP exhibited a heightened proapoptotic state, as indicated by an increased Bak expression and Bak/Bcl-Xl expression ratio, as well as a reduced Bcl-Xl expression. IVIG therapy appears to mitigate this pro-apoptotic effect, suggesting its ability to restore platelet homeostasis.