MTOR and sialidosis: Unstimulated basal levels of autophagic vacuoles were not detectable in either normal- or sialidosis-iNPCs by the CYTO-ID autophagy detection assay; thus, we evaluated the impact of rapamycin, an mTOR-dependent autophagy inducer [31], in the sialidosis-iNPCs and compared them to normal-iNPCs (Figure 4A,B, green).