Ocular muscle myasthenia gravis (Ocular Myasthenia Gravis, OMG) has a high incidence and is difficult to diagnose. It is very necessary to find specific diagnostic indicators for OMG. By collecting peripheral blood of OMG, systemic myasthenia gravis and healthy people, extract miRNAs derived from exosomes in the serum and perform high-throughput sequencing, then use bioinformatics analysis methods to screen specifically expressed miRNAs as biomarkers for OMG diagnosis .

Part I: (1) Collect peripheral blood samples from patients with early-onset OMG, early-onset GMG and healthy subjects of age and sex matched who have been diagnosed for the first time and have not undergone any drug treatment. There are 6 cases in each group. Extract the secretion miRNA in serum and conduct high-throughput sequencing. Analyze and compare the differential expression miRNAs between OMG, GMG and healthy control groups by edgeR. The standard of differential expression is set as | logFC |>1, p<0.05. Use miRTarBase, TargetScan, and miRDB to predict target genes for differentially expressed miRNAs. Conduct GO enrichment and KEGG signaling pathway analysis on target genes. The STRING tool is used to construct the target gene protein interaction network (PPI). According to the importance of the target gene calculated by the maximum population concentration ratio (MCC) method, the top ten genes (hub genes) are selected and analyzed.

(2) Randomly collect peripheral blood samples from patients with early-onset OMG, early-onset GMG, and age-matched healthy subjects, with 10 samples in each group. The differentially expressed miRNAs obtained during the sequencing phase were validated using real-time fluorescence quantification (RT-qPCR). Construct a receiver operating characteristic curve (ROC) curve to evaluate the diagnostic efficacy of the identified miRNA.

Inclusion Criteria:

• Clinical manifestations: fluctuating myasthenia;

  • neostigmine test positive; ③ AChR-Ab, Musk-Ab, LRP4-Ab antibodies positive; ④repetitive nerve stimulation or single fiber EMG Positive (comply with the first one of the above diagnostic criteria and any one of the other three, and at the same time exclude ophthalmoplegia caused by other diseases, the diagnosis can be confirmed).

Exclusion Criteria:

①Combined with other autoimmune diseases or other inflammatory diseases; ②Patients with tumorous diseases;

• Received targeted biologics, intravenous gamma globulin, plasma exchange therapy within three months before treatment; ④Pregnancy Status or lactation

People within age 18-50 years old who is diagnosed with OMG,GMG or healthy people.