Efficient proximal tubule-on-chip model from hiPSC-derived kidney organoids for functional analysis of renal transporters.

Renal transporters play critical roles in predicting potential drug-drug interactions. However, current models often fail to adequately express these transporters, particularly solute carrier proteins, including organic anion transporters (OAT1/3), and organic cation transporter 2 (OCT2). Here, we developed a hiPSC-derived kidney organoids-based proximal tubule-on-chip (OPTC) model that emulates renal physiology to assess transporter function. Compared to chips based on immortalized cells, OPTC derived from the two most commonly used differentiation protocols exhibited significant improvement in expression level and polarity of OAT1/3 and OCT2. Hence, the OPTC demonstrates enhanced functionality in efflux and uptake assessments, and nephrotoxicity. Furthermore, these functionalities are diminished upon adding inhibitors during substrate-inhibitor interactions, which were closer to observations. Overall, these results support that OPTC can reliably assess the role of renal transporters in drug transport and nephrotoxicity, paving the way for personalized models to assess renal transport and disease modeling.