Compared with those in the 3 day control group, the mRNA levels of the tight junction-related genes claudin-1, ZO-1 and occludin were significantly lower after TOC was infected with MG, and the mRNA expression levels at each time point were significantly greater than those in the control group (p < 0.01) (Figure 6). The gene discussed is TJP1; the disease is myasthenia gravis.