Although previous studies have indicated that the BBB remains intact and functionally unchanged in patients with MG [66, 67], our findings in Fig. 4 demonstrate a downregulation of Claudin5 (Cldn5), CXC43 (Gja1) and CD31 (Pecam1) expression in cerebral microvascular ECs of EAMG rats as assessed by western blot and qPCR. The gene discussed is GJA1; the disease is myasthenia gravis.