Van Den Berg et al. (2002) showed that IL-4 increases intracellular trafficking of proteins in glomerular visceral epithelial cells. Olsan et al. (2015), using human autosomal-dominant polycystic kidney disease tissues, showed that STAT6 pathway activation induces an increase in renal pIgR, which is involved in renal cell IgA transport. Here, STAT6 is linked to autosomal dominant polycystic kidney disease.