Increased serum IL-27 concentrations and IL-27-producing cells in MG patients with positive AChR-Ab.

Objective: This study aims to explore the serum levels of IL-27 and the percentages of IL-27-producing cells in MG patients with positive acetylcholine receptor antibody (AChR-MG).

Methods: A total of 17 AChR-MG patients and 22 sex- and age- matched healthy controls (HCs) were recruited. Serum IL-27 levels were determined by enzyme linked immunosorbent assay. The percentages of IL-27 cells, IL-27-producing T (CD3IL-27) cells, and IL-27-producing B (CD19IL-27) cells were measured by flow cytometry.

Results: Serum IL-27 levels in AChR-MG were significantly higher than those in HCs (13.44 ± 0.89 vs 7.14 ± 0.75 pg/mL, P < 0.0001), and were decreased after intravenous immunoglobulin (IVIG) treatment (P = 0.004). Moreover, the frequencies of IL-27 lymphocytes were significantly elevated in AChR-MG patients than those in HCs (P = 0.011), and were decreased after IVIG treatment (P = 0.014). Furthermore, the frequencies of IL-27-producing T cells (P = 0.017) and IL-27-producing B cells (P = 0.015) were significantly elevated in AChR-MG patients as compared to those in HCs. Meanwhile, we observed positive correlations between the frequencies of IL-27 lymphocytes and MG-ADL score (P = 0.030, r = 0.527). By contrast, no significant correlation was found between IL and 27 serum levels and MG-ADL score (P = 0.099, r = -0.414).

Conclusion: IL-27 may play an important role in the pathological process in AChR-MG patients, and the frequencies of IL-27-producing (CD3IL-27) T cells may be a potential biomarker for predicting the severity of AChR-MG.