Abstract:

Objective: Hyper-IgE syndrome (HIES) is characterized by susceptibility to infection and low number of Th17 cells. Th17 is believed to be critical in the clearance of fungal and extracellular bacterial infections. Present study investigates the differentiation of Th17 cells by evaluation of interleukin 17 (IL-17) secretion and ….. (ROR?t) expression in HIES compared with healthy subjects. Method: Three children diagnosed with HIES and 4 healthy subjects were enrolled in the study. HIES scores were evaluated and clinical data of patients were collected from their hospital records. At Th17 polarizing conditions, Th17 differentiation was assessed by the secretion of IL-17 with ELISA and the expression of ROR-?t with real time PCR. Results: HIES (n=3) patients showed significantly lower levels of IL-17 secretion compared to the healthy subjects (n=4) regarding the peripheral blood mononuclear cells (PBMCs) and CD45+RA naive T cells cultured in Th17 differentiating conditions. In addition, phorbol 12-myristate 13-acetate (PMA) and ionomycin stimulated IL-17 levels of healthy group were significantly higher than unstimulated conditions. Moreover, PMA and ionomycin stimulated IL-17 levels of PBMC cultures were significantly higher when compared to unstimulated conditions for both HIES patients and healthy subjects. ROR-?t expression level of stimulated PBMCs for HIES patient was detected nearly half of that of the healthy subject.  Conclusion: Evaluation of IL-17 secretion and ROR-?t expression should be performed to determine the patients who are candidates for mutation analyses. Performing these steps and selection of HIES patients without known mutations in our country would provide an opportunity to discover new genetic defects and so new therapeutic approaches in HIES.

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