Search bioRxiv⌕ Search

Biology subjects

Mason, W. J.

Publications and source records attributed to Mason, W. J..

2 recordsLinked to original sources

Exploration of single-cell transcriptomic landscape identifies aberrant glomerular crosstalk in a murine model of WT1 kidney disease

The glomerulus mediates kidney ultrafiltration through specialised epithelial cells called podocytes which line a basement membrane shared with blood capillary endothelium. Cell-cell crosstalk is critical for glomerular function, but its investigation in childhood glomerular diseases has received little attention. WT1 encodes a transcription factor expressed in podocytes, whose heterozygous variants cause devastating kidney disease in childhood. We used single-cell RNA sequencing and ligand-receptor interaction analysis to resolve the glomerular transcriptional landscape of mice that carry an orthologous human mutation in WT1 (Wt1R394W/+). Podocytes were the most dysregulated cell type in early disease, with disrupted angiogenic signalling preceding glomerular capillary loss. Comparative analyses with additional murine and human glomerular disease datasets identified unique transcriptional changes in WT1 glomerular disease, reflecting a non-immunological pathology, whilst revealing a common injury signature across multiple glomerular diseases. Collectively, this work advocates vascular-based therapies over immunosuppressive drugs in the treatment of WT1 glomerular disease.

cell biology↗

Systemic gene therapy with thymosin β4 alleviates glomerular injury in mice

Plasma ultrafiltration in the kidney occurs across glomerular capillaries, which are surrounded by epithelial cells called podocytes. Podocytes have a unique shape maintained by a complex cytoskeleton, which becomes disrupted in glomerular disease resulting in defective filtration and albuminuria. Lack of endogenous thymosin {beta}4 (TB4), an actin sequestering peptide, exacerbates glomerular injury and disrupts the organisation of the podocyte actin cytoskeleton, however, the effect of exogenous TB4 therapy on podocytopathy is unknown. Here, through interrogating single-cell RNA-sequencing data of isolated glomeruli we demonstrate that Adriamycin, a toxin which injures podocytes and leads to leakage of albumin in the urine of mice, results in reduced levels of podocyte TB4. Systemic administration of an adeno-associated virus vector encoding TB4 prevented Adriamycin-induced podocyte loss and albuminuria. Adriamycin injury was associated with disorganisation of the actin cytoskeleton in vitro, which was ameliorated by exogenous TB4. Furthermore, Adriamycin administration in mice was associated with increased prevalence of podocyte vesicles, a mechanism by which albumin may leak into the urine, which was also prevented by TB4. Collectively, we propose that TB4 gene therapy prevents podocyte injury and maintains glomerular filtration via modulation of the podocyte cytoskeleton thus presenting a novel treatment strategy for glomerular disease.

physiology↗