The accumulation of the autophagy substrate SQSTM1, which is normally degraded within autolysosomes, suggests an abnormal autophagy flux in cystinosin-deficient PT cells, in line with recent observations stating an impairment of autophagy flux in many lysosome storage diseases37,38 and evidence in human cells and kidney biopsies from cystinosis patients16. This evidence concerns the gene SQSTM1 and cystinosis.