(665.13) Growth and differentiation of human induced pluripotent stem cell (hiPSC) derived kidney organoids using fully synthetic peptide hydrogels

Poster Board Number: A311

Niall Treacy (UCD School of Biomolecular and Biomedical Science), Shane Clerkin (UCD School of Biomolecular and Biomedical Science), Jessica Davis (UCD School of Biomolecular and Biomedical Science), Ciarán Kennedy (UCD School of Biomolecular and Biomedical Science), Jacek Wychowaniec (AO Research Institute Davos), Dermot Brougham (UCD School of Chemistry), John Crean (UCD School of Biomolecular and Biomedical Science)

Human induced pluripotent stem cell (hiPSC)-derived kidney organoids have prospective applications ranging from basic disease modelling to personalised medicine. However, there remains a necessity to refine the biophysical and biochemical parameters that govern kidney organoid formation. Differentiation within fully-controllable and physiologically relevant 3D growth environments will be critical to improving organoid reproducibility and maturation. Here, we matured hiPSC-derived kidney organoids within fully synthetic self-assembling peptide hydrogels (SAPHs) of variable stiffness (storage modulus, G′). The resulting organoids contained complex structures comparable to  those differentiated within the animal-derived matrix, Matrigel. Single-cell RNA sequencing (scRNA-seq) was then used to compare organoids matured within SAPHs to those grown within Matrigel or at the air-liquid interface. A total of 13,179 cells were analysed, revealing 14 distinct clusters. Organoid compositional analysis revealed a larger proportion of nephron cell types within Transwell-derived organoids, while SAPH derived organoids were enriched for stromal-associated cell populations. Notably, differentiation within a higher G’ SAPH generated  podocytes with more mature gene expression profiles. Additionally, maturation within a 3D microenvironment significantly reduced the derivation of offtarget cell types, which are a known limitation of current kidney organoid protocols. This work demonstrates the utility of synthetic peptide-based hydrogels with a defined stiffness, as a minimally complex microenvironment for the selected differentiation of kidney organoids.

This work has emanated from research conducted with the financial support of Science Foundation Ireland (SFI) and is co-funded under the European Regional Development Fund under Grant Number 13/RC/2073_P2. The authors acknowledge support from Science Foundation Ireland (16/IA/4584) and 19/FFP/6833. J.K.W. would also like to acknowledge Royal Society of Chemistry grant (M19-6613).