Immunological markers changes in pediatric immune Thrombocytopenic Purpura

Background Individuals with immune thrombocytopenic purpura (ITP) have cellular immune responses that show the characteristics of tolerance mechanisms that have broken down. Objectives This study aimed to assess the percentage of regulatory T cells (Tregs) and CD4 lymphocytes that express CXCR6 in untreated newly diagnosed ITP in pediatric patients and their correlation with each other, the platelet (PLT) count and other PLT indices. Patients and methods A case–control study was carried out that included 40 pediatric patients with ITP, and 20 age-matched and sex-matched healthy controls were selected from Benha Children Hospital hematology clinic. Assessment of CD4+, CD25+, and FoxP3+as markers of Treg cells and also expression of the CXCR6 receptor on CD4+ T lymphocytes to evaluate the percentage of Tregs and CD4/CXCR6 +T lymphocytes were investigated by flow cytometry. Results There was a marked reduction in CD4/CXCR6 and Tregs (P=0.02 and 0.001) in the ITP group versus the control group. In contrast, there was a marked increase in CD4/CD25+cells (P=0.002) in the ITP group compared with the control group. There was a considerable reduction in the PLT count and the hemoglobin concentration in the ITP group compared with the control group (P=0.000 and 0.01), while there was a significant increase in large platelet cell ratio and platelet distribution width in the ITP group in comparison to the control group (P=0.04 for both of them); also, there were insignificant differences in total leukocytic count and mean platelet volume in the ITP group in comparison to the control group (P=0.28 and 0.77). Conclusion There was a significant decrease in the concentration of CD4+ cells that express CXCR6+ and Treg percentage in ITP patients as compared with the controls, which may explain the defect in immune self-tolerance in ITP patients.