Study of the role of IL-17F gene polymorphism in the development of immune thrombocytopenia among the Egyptian children

Contribution of T helper 17 cells and interleukin-17 to the pathogenesis of primary immune thrombocytopenia in Egyptian children

Though pathogenesis of primary immune thrombocytopenia (ITP) is still rendered unclear, yet there are many research efforts that have been directed to the role of T helper 17 (Th17) and interleukin 17 (IL-17) in the pathogenesis of this disease. The Th17 cell, which produces IL-17, is a subset of T helper cells. Interleukin 17 is pro-inflammatory cytokine that is recently proved to have a crucial role in the emergence of autoimmune diseases. We aimed to investigate the role of T helper17 cells and interleukin-17 in the pathogenesis of ITP in Egyptian children. This study was carried out on 100 children with ITP and 100 apparently healthy children as a control group. Patients were subjected to full medical history taking, thorough physical examination and routine investigations according to our local standards. Percentage of Th17 cells was measured by flow cytometry in study groups. Also, serum IL-17 was measured in in study groups by ELISA. Th 17 cells were significantly higher in patients compared to controls. Moreover, 3.1-fold increased serum levels of IL-17 were observed in patients with ITP compared to controls. Newly diagnosed patients had significantly higher percentage of Th-17cells as well as higher IL-17 levels than patients with either persistent or chronic ITP.   Conclusion: We concluded that Th 17 cells and IL-17 seem to play an important role in the pathogenesis of ITP in Egyptian children. What is Known -- What is New: • The pathogenesis of ITP is heterogeneous A novel subset of CD4+ T cells, distinct from Th1 and Th2, was recently identified. It is characterized by the production of IL-17 and, therefore, designated as Th17 cells. Several studies support a pivotal role for serum cytokines in the pathogenesis of ITP and provide evidence to suggest that helper Tlymphocytes polarize into Th1 and Th2 immune response. we aimed to investigate the role of T helper17 cells and interleukin-17 in the pathogenesis of ITP in Egyptian children.

Genetic polymorphism of IL-17F rs763780 contributes to the susceptibility to bipolar disorder but not to schizophrenia in the Turkish population

This study aims to investigate the genetic polymorphism in the interleukin-17F (IL-17F) (rs763780, 7488 A/G) gene in bipolar disorder (BD) and schizophrenia (SCZ) patients by comparing it with healthy controls considering clinical parameters. A sample of 107 patients with BD, 129 patients with SCZ, and 100 healthy volunteers were included. SCID-I was used to confirm the diagnosis according to DSM-IV-TR criteria. The Young Mania Rating Scale (YMRS) and the Hamilton Depression Rating Scale (HAM-D) were administered to BD patients. The Positive and Negative Symptoms Scale (PANSS) was applied to the patients with SCZ. PCR-RFLP was used to determine IL-17F gene polymorphism. Our results demonstrated that the distributions of the IL-17F genotype and the allele frequencies of BD patients were statistically significantly different from the control group. The AA genotype (OR: 0.283; 95% Cl: 0.140-0.573; p<.001) and A allele (OR: 0.333; 95% Cl: 0.171-0.646; p=.001) frequencies were significantly higher in the control group than in the BD group. The IL-17F genotype and the allele frequency distributions of SCZ patients were not statistically significantly different from the control group. When comparing scale scores due to the IL-17F genotype distributions in patients with BD or SCZ, there was no statistically significant difference between the groups of IL-17F genotypes. In summary, whereas the IL-17F polymorphism may be associated with BD, this polymorphism was not related to SCZ.

CD4+ T cell phenotypes in the pathogenesis of immune thrombocytopenia

Immune thrombocytopenia (ITP) is an autoimmune disorder characterized by low platelet counts due to enhanced platelet clearance and compromised production. Traditionally, ITP was regarded a B cell mediated disorder as anti-platelet antibodies are detected in most patients. The very nature of self-antigens, evident processes of isotype switching and the affinity maturation of anti-platelet antibodies indicate that B cells in order to mount anti-platelet immune response require assistance of auto-reactive CD4⁺ T cells. For a long time, ITP pathogenesis has been exclusively reviewed through the prism of the disturbed balance between Th1 and Th2 subsets of CD4⁺ T cells, however, more recently new subsets of these cells have been described including Th17, Th9, Th22, T follicular helper and regulatory T cells. In this paper, we review the current understanding of the role and immunological mechanisms by which CD4⁺ T cells contribute to the pathogenesis of ITP.