MRC1 and Charcot-Marie-Tooth disease type 1A: We thus examined a potential expression of CXCL13+ macrophages in the sciatic nerves of C22 mice, an animal model of CMT1a, and found that most macrophages were CD206-positive but CXCL13-negative (Fig. 3D,E), which was in line with the normal serum levels of CXCL13 in the CMT1a patients (Fig. 3A).