Effects of Follicular Helper T Cells and Inflammatory Cytokines on Myasthenia Gravis.

BACKGROUND

Myasthenia gravis (MG) is an autoimmune disorder mediated by antibodies against the acetylcholine receptors (AChR) of the skeletal muscles. An imbalance in various T helper (Th) cells, including Th1, Th2, Th17, Th22 and follicular helper T (TFH) cells, has been found associated with immunological disturbances.

OBJECTIVE

In this study, we aim to investigate the role of the Th cells in peripheral blood of MG patients.

MATERIALS AND

METHODS

A total of 33 MG patients and 34 age matched controls were enrolled in this study. Peripheral blood mononuclear cells (PBMCs) were isolated using Ficoll-Paque density gradient centrifugation assay. The proportion of TFH cells in PBMC were analyzed using flow-cytometry assay by determining the levels of cellular markers CD4, CXCR5, CD45RO, CD45RA and ICOS and PD-1. The levels of IFN-γ, IL-4, IL-17 and IL-21 in serum were analyzed by Cytometric Bead Array. The serum IL-22 level was analyzed by ELISA.

RESULTS

The frequency of TFH cells in PBMCs was higher than those in healthy subjects and correlated to the severity of MG patients. The levels of pro-inflammatory cytokines IFN-γ, IL-17 and IL-21 were elevated in the serum of MG patients, while there were no significant differences regarding the levels of IL-4 and IL-22 between MG patients and control subjects.

CONCLUSION

Our findings suggest that Th cells and their cytokines balance of MG patients are involved in the clinical condition or severity of MG disease.