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Touw, D. J.

Publications and source records attributed to Touw, D. J..

2 recordsLinked to original sources

Comparison of hiPSC-derived hepatic organoids and liver-on-a-chip systems reveal microenvironment-driven maturation

Human liver organoids (HLOs) and liver-on-a-chip (LoC) systems are emerging as physiologically relevant human models for studying liver function, disease, and drug metabolism, often in combination with human induced pluripotent stem cell (hiPSC)-derived tissues. However, hiPSC-derived models often display batch-to-batch variation and incomplete maturation, and the contribution of microfluidic flow to hepatic maturation remains insufficiently characterized. Here, we developed a cryopreservable and scalable workflow to generate hiPSC-derived hepatic organoids that can be directly matured to either static HLOs or LoC systems, enabling matched comparison of both platforms. Transcriptomic and functional characterization revealed progressive hepatic maturation during organoid differentiation, including increased expression of liver-specific metabolic pathways, enhanced albumin secretion, and increased CYP3A4 activity. Compared to mature HLOs, LoCs exposed to continuous microfluidic flow exhibited transcriptomic profiles suggesting further maturation, with increased enrichment of pathways related to lipid metabolism, xenobiotic metabolism, transport, and tissue organization. These findings demonstrate that microfluidic perfusion promotes hepatic metabolic specialization compared to static organoid culture while maintaining donor-specific characteristics. Together, this study establishes a robust hiPSC-derived LoC platform and highlights the potential of flow-based systems for improved modeling of human liver physiology, disease mechanisms, and drug responses.

cell biology↗

Exploring ex vivo modulation of fibrosis in discarded human donor kidneys

IntroductionEarly-onset fibrosis limits kidney transplant success. Normothermic machine perfusion (NMP) offers a platform for targeted drug delivery directly to isolated organs, minimizing systemic effects. This study evaluated the long-term anti-fibrotic efficacy and safety of galunisertib in discarded human kidneys perfused ex vivo. MethodsTwelve discarded human kidneys underwent 4 hours of oxygenated hypothermic perfusion followed by 6 hours of NMP with galunisertib or vehicle (n=6). Precision-cut kidney slices (PCKS) were then cultured for 48 hours with either continued or discontinued galunisertib exposure. Endpoints included fibrosis-related mRNA expression and pharmacokinetics. ResultsGalunisertib did not negatively affect renal function during NMP. Continued exposure in PCKS significantly attenuated fibrosis-related mRNA expression, including SERPINE1 (p=0.0046), TGF-{beta} (p=0.0168), FN1 (p=0.0269) and ACTA2 (p=0.0014) after 48 hours. The discontinuation of treatment did not exhibit the same anti-fibrotic effects. ConclusionGalunisertib was safely administered during NMP and steadily excreted via the urine. NMP showed to be a promising platform for safe targeted anti-fibrotic therapy delivery, offering potential to improve graft quality. When treatment was sustained, galunisertib induced a modest reduction in fibrosis-related mRNA expression over 48 hours of tissue incubation. Further studies are needed to optimize delivery strategies and evaluate the impact of prolonged therapeutic exposure.

pharmacology and toxicology↗