Kidney organoids: A system to study human basement membrane assembly in health and disease

Abstract

Basement membranes (BMs) are complex macromolecular networks underlying all continuous layers of cells. Essential components include type IV collagen and laminins, which are affected by human genetic defects 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 vertebrate BM assembly and provide a platform for understanding its wider relevance in human development and disease.

A basement membrane discovery pipeline uncovers network complexity, new regulators, and human disease associations

“…Postmortem fetal tissue from the LAMA5 cases was used with prior parental consent for use in research. The control 21-week human fetal kidney sections were acquired in a previous study 79 and were initially provided by the Joint MRC/Wellcome Trust Human Developmental Biology Resource (HDBR) (http://hdbr.org). We were unable to obtain further clinical details or tissue samples from the reported individuals with MPZL2 and MATN2 variants.…”

“…The lysate and the ECM-rich fractions were processed for in-solution digestion as described previously 79 . To extract proteins, samples were lysed using a Covaris LE220+ Focused Ultrasonicator (Covaris).…”

An integrated organoid omics map extends modeling potential of kidney disease

“…raising the potential for organoid modeling of these diseases. Furthermore, proteins related to cystinosis 44 immunode ciency, porphyria and hyperoxaluria were also expressed, supporting development of personalized disease models of kidney phenotypes 7,45 . Yet, we were unable to detect expression of many tubule-speci c proteins such as glucose transporter SGLT2 in our organoids, as well as almost all proteins that are known to be expressed in cells in the collecting duct.…”