ARG1 and myasthenia gravis: Moreover, the results of immunofluorescence staining showed that the expression levels of Arg1 and ym1 (markers of M2) in MG tissues were significantly lower in severe MGD patients than those in mild MGD patients (p = 0.0041, p = 0.0001), which is consistent with the results of the macrophage infiltration in the MGD mouse model (Figure 4A,B).