Kidney organoids recapitulate human basement membrane assembly in health and disease.

Pinyuan Tian,Mychel Rpt Morais,David A Long,Syed Murtuza-Baker,Rachel Lennon,Roy Zent,Craig Lawless,Steven Woods,Daniel P Gale,Aleksandr Mironov,Susan J Kimber,Telma Mt Zorn,Louise Hopkinson

doi:10.7554/elife.73486

Abstract

Basement membranes (BMs) are complex macromolecular networks underlying all continuous layers of cells. Essential components include collagen IV and laminins, which are affected by human genetic variants leading to a range of debilitating conditions including kidney, muscle, and cerebrovascular phenotypes. We investigated the dynamics of BM assembly in human pluripotent stem cell-derived kidney organoids. We resolved their global BM composition and discovered a conserved temporal sequence in BM assembly that paralleled mammalian fetal kidneys. We identified the emergence of key BM isoforms, which were altered by a pathogenic variant in COL4A5. Integrating organoid, fetal, and adult kidney proteomes, we found dynamic regulation of BM composition through development to adulthood, and with single-cell transcriptomic analysis we mapped the cellular origins of BM components. Overall, we define the complex and dynamic nature of kidney organoid BM assembly and provide a platform for understanding its wider relevance in human development and disease.

Highlights

64 Basement membranes (BMs) surround tissues providing cells with an interface for physical and signaling interactions (Jayadev and Sherwood, 2017)
We demonstrate that kidney organoids represent 122 a high-fidelity system to study the dynamics of human BM assembly
124 RESULTS 125 Kidney organoids form BM networks that are altered with defective COL4A5

Summary

Introduction

64 Basement membranes (BMs) surround tissues providing cells with an interface for physical and signaling interactions (Jayadev and Sherwood, 2017). Situated between podocytes and endothelial cells in the glomerular capillary wall, the GBM is formed by the fusion of separate podocyte and endothelial BMs, and further remodeled into a mature GBM This involves replacement of laminin 1 1 1 (termed laminin-111) and collagen IV 1 1 2 networks by laminin-511 -521, and collagen IV 3 4 5 (Abrahamson et al, 2013; Abrahamson and St John, 1993). Proteomics lacks the spatial context that is captured by localization studies including fluorescent tagging of endogenous proteins Such investigations in Drosophila and C. elegans have unraveled dynamic features of BM assembly in embryogenesis and repair (Howard et al, 2019; Keeley et al, 2020; Matsubayashi et al, 2020). Whilst understanding about cell types in kidney organoids has progressed significantly, there is a knowledge gap about extracellular matrix and BM assembly during 114 differentiation

Results

Discussion

Conclusion