To validate the perineurial hyperplasia in CIDP, we histologically stained epithelial membrane antigen (EMA)28 in 18 additional controls (residual material of surgical sural nerve autografts) and 12 CIDP patients (Supplementary Data 10) and measured the area and perimeter of the perineurium for each fascicle (370 fascicles in total) (Fig. 5D). Here, MUC1 is linked to chronic inflammatory demyelinating polyradiculoneuropathy.