[Thymoma T helper type 17 cells and related cytokines in myasthenia gravis].

Objective: To investigate the immunoregulatory role of Th17 cell and the related cytokines in myasthenia gravis.

Methods: Totally 51 myasthenia gravis (MG) patients were divided into MG with thymomas (TM group) and the MG with normal thymus (NT group), as well as 22 healthy subjects as controls. Th17 cells from peripheral blood mononuclear cells were measured by flow cytometry. Th17 related cytokines were detected by ELISA and real-time quantitative-PCR.

Results: The quantity of Th17 cells in MG patients with thymomas (1.53 ± 0.59)% were significantly increased compared with that of healthy control (0.94% ± 0.32%, P < 0.05). There was no significant difference in the number of Th17 cells between healthy controls and NT group. The expression levels of IL-17 mRNA (23.7 ± 4.5) were up-regulated significantly versus those in healthy controls (13.4 ± 3.2, P < 0.01). The levels of mRNA expression of IL-1β, IL-6 and IL-23 were up-regulated significantly in TM group. The mean concentration of IL-17 was up-regulated significantly in TM group (30.4 ± 7.3) ng/L versus healthy controls [(19.2 ± 4.9) ng/L, P < 0.05]. Serum levels of IL-23 and IL-1β were always increased in TM group versus healthy controls.

Conclusion: The elevated levels of IL-17 and other Th17 related cytokines in thymomas may aggravate the autoimmunity disorder.