Serum irisin levels in patients with myasthenia gravis.

OBJECTIVE: Myasthenia gravis (MG) is an autoimmune disorder whose main symptoms are muscle weakness and fatigue. Irisin is a novel skeletal muscle-derived myokine participating in several physiological and pathological processes. The initial objective of the project was to explore serum levels of irisin in patients with MG, as well as its correlation with disease severity. METHODS: We retrospectively evaluated serum levels of irisin in 77 MG patients and 57 healthy controls (HCs) by enzyme-linked immunosorbent assay. Further, clinical parameters were measured properly. RESULTS: Serum irisin levels were significantly elevated in MG patients compared with HCs (p < 0.001). Furthermore, serum irisin levels were associated with the myasthenia gravis activities of daily living score in ocular myasthenia gravis (OMG) patients (r = 0.476, p = 0.004), but there was no relationship to be considered of any relevant value in generalized myasthenia gravis (GMG) patients. Acetylcholine receptor antibody-positive MG patients had higher serum irisin levels compared with HCs. Thymoma, endotracheal intubation, or intensive care unit treatments subsequently were not found to have effect on serum levels of irisin, but tendencies of increase were observed in negative ones. CONCLUSIONS: Serum irisin levels were elevated in patients with MG, suggesting its possible involvement in MG. And irisin is expected to be a signal to evaluate the activities of daily living of OMG patients, while its effect needs further study.

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 (CD3+IL-27+) cells, and IL-27-producing B (CD19+IL-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 (CD3+IL-27+) T cells may be a potential biomarker for predicting the severity of AChR-MG.

Different clinical characteristics of longitudinally extensive transverse myelitis with and without connective tissue disorders: a single-center retrospective study.

BACKGROUND AND OBJECTIVE: Autoimmune longitudinal extensive transverse myelitis (LETM) is often combined with connective tissue disorders (CTD). The purpose of this study was to compare the clinical characteristics of autoimmune LETM with and without CTD. METHODS: Ninety-two patients diagnosed with autoimmune LETM were enrolled from our clinical database and divided into two groups depending on whether they had a concomitant diagnosis of CTD. Differences in clinical, serological, and imaging characteristics between the two groups were evaluated and compared. RESULTS: Fifty-nine LETM patients without CTD and 33 LETM patients with CTD were included. LETM patients with CTD had higher Kurtzke Expanded Disability Status Scale at nadir and more severe sensory dysfunction (p < 0.05) than those without CTD. It was also found that LETM patients with CTD, compared with those without CTD, had elevated levels of immune inflammation markers such as IgG, IgA, and globulins (p < 0.05). These abovementioned characteristics were more prominent in patients with aquaporin-4 antibodies (AQP4-ab) than in those without them. In addition, the most common type of CTD in LETM was Sjögren syndrome (SS), which was usually diagnosed at the time of LETM or later. CONCLUSION: LETM patients with CTD, especially those with AQP4-ab, had greater sensory dysfunction and higher levels of inflammatory markers than did LETM patients without CTD. Multicenter cooperation and long-term follow-up are necessary to further study the inherent implications and prognosis of the disease.