AEB-071 Ameliorates Muscle Weakness by Altering Helper T Lymphocytes in an Experimental Autoimmune Myasthenia Gravis Rat Model.

BACKGROUND Myasthenia gravis (MG) is an autoimmune neurological disorder of neuromuscular junctions. In this study we established experimental autoimmune myasthenia gravis (EAMG) rat models to investigate the effects of AEB-071 (AEB), which is a specific inhibitor of protein kinase C that prevents T lymphocyte activation. MATERIAL AND METHODS We utilized animals divided into 4 groups: (1) control rats, (2) EAMG, (3) AEB-071+EAMG, and (4) AZP+EAMG. Drug treatment was continued for 10 days. Ten weeks after immunization we measured body weights, assessed mortality rates, and used Lennon scores to evaluate EAMG grades. We also assessed the proportions of Treg, Th1, Th2, Th17, and lymphocytes using flow cytometry. RESULTS In the absence of drug treatment, we found a significant decline in body weights in the EAMG group in comparison to control rats, and EAMG group rats also had higher Lennon scores (P<0.05). Interestingly, we found that AEB-071 restored the body weight of EAMG rats and the decreased mortality rate compared to AZP treatment. Although a decrease in the number of Treg cells was observed, the proportion of Th lymphocytes was significantly increased in the EAMG group, and AEB-071 treatment decreased the proportion of Th lymphocytes. CONCLUSIONS We concluded that AEB-071 treatment imparts beneficial effects in EAMG rat models by reducing mortality rate and restoring Th lymphocyte balance, and thus may be an attractive candidate for use in MG treatment.