Research Information System
Kidney Week 2021, California, United States Of America, 4 - 07 November 2021, pp.152
Background: Acute kidney injury (AKI), with high mortality, is a serious public health issue. Hypoxic injury in proximal tubules (PT) sets the course of ischemic AKI. Microfluidic organ-on-a-chip technology mimics 3D kidney structures in vitro. We asked if AKI-related hypoxic injury may be modelled on a microfluidic 3D PT system comprising human epithelial cells and extracellular matrix (ECM).
Methods: A 2-lane microfluidic device without membrane was set to model 3D PT. Human PT epithelial cells (HK-2) were cultured with K-SFM media against ECM. Hypoxic conditions was designed as 1% O2 , 5% CO 2 and 94% N 2 in humidified multi-gas incubator. Tubular injury was assessed by immunofluorescence (IF) labelling and barrier integrity assay for 48 hours.
Results: Proximal tubules formed successfully at normoxia by phase contrast microscope. Hypoxia increased tubular leakage by 6-fold for 20 kDa (Fig. 1B, p=0.001) and 4-fold for 155 kDa molecules (Fig. 1C, p=0.001) compared to normoxia on 24h. Leakage for 20 kDa molecules remained 2-fold high compared to normoxia on 48h (Fig. 1B, p=0.001). Leakage for 155 kDa molecules restored with similar data as normoxia (Fig. 1C, p=0.268) on 48h. IF data supported impairment of the barrier.
Conclusions: In this study, a novel human kidney PT-on-a-chip was designed and successfully optimized for real time-modelling acute hypoxic tubular injury in AKI. Our human PT-on-a-chip mimics reversible tubule injury of clinical AKI more accurately compared to severe animal tubular damage models and presents a reliable and adjustable platform for testing potential therapeutic interventions. Hacettepe University Research Fund financially supported this work (TSA-2020-18383).
Funding: Government Support - Non-U.S.