FOXP3 and myasthenia gravis: However, it is interesting that as an important factor in the pathogenesis of MG, anti-AChR Ab showed significant positive correlation with Tr1 cells instead of FoxP3+ Tregs (Figure 6), suggesting that as immune regulatory cells, Tr1 cells may serve as a powerful supplement to the Treg cell population and play a crucial role in regulating the immune response induced by anti-AChR Ab.