DPP4 and lysosomal storage disease: The observed abnormalities in LRs also affect protein trafficking to outer plasma membrane, as shown previously by Maalouf et al. [7] and further described here for DPPIV with less protein on cell surface in FD fibroblasts (Supplementary Figure S9), supporting the view that LRs are implicated in the trafficking and sorting of a variety of membrane proteins and their distortion, as shown in FD, could play a role in the pathophysiology of other lysosomal storage diseases [29].