Publications by authors named "Adam T Piers"

3 Publications

  • Page 1 of 1

Generating an iPSC line (with isogenic control) from the PBMCs of an ACTA1 (p.Gly148Asp) nemaline myopathy patient.

Stem Cell Res 2021 Jul 17;54:102429. Epub 2021 Jun 17.

Murdoch Children's Research Institute, Melbourne, Victoria, Australia; Department of Pediatrics, The University of Melbourne, Victoria, Australia. Electronic address:

To produce an in vitro model of nemaline myopathy, we reprogrammed the peripheral blood mononuclear cells (PBMCs) of a patient with a heterozygous p.Gly148Asp mutation in exon 3 of the ACTA1 gene to iPSCs. Using CRISPR/Cas9 gene editing we corrected the mutation to generate an isogenic control line. Both the mutant and control show a normal karyotype, express pluripotency markers and could differentiae into the three cell states that represent embryonic germ layers (endoderm, mesoderm and neuroectoderm) and the dermomyotome (precursor of skeletal muscle). When differentiated these cell lines will be used to explore disease mechanisms and evaluate novel therapeutics.
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July 2021

Sex-Specific Control of Human Heart Maturation by the Progesterone Receptor.

Circulation 2021 Apr 8;143(16):1614-1628. Epub 2021 Mar 8.

Murdoch Children's Research Institute (C.B.S., B.P., K.D.A.-B., R.K.R.K., H.K.V., M.t.H., C.J.V., A.H., A.T.P., I.E.K., D.A.E., A.O., E.R.P.), The Royal Children's Hospital, Melbourne, Victoria, Australia.

Background: Despite in-depth knowledge of the molecular mechanisms controlling embryonic heart development, little is known about the signals governing postnatal maturation of the human heart.

Methods: Single-nucleus RNA sequencing of 54 140 nuclei from 9 human donors was used to profile transcriptional changes in diverse cardiac cell types during maturation from fetal stages to adulthood. Bulk RNA sequencing and the Assay for Transposase-Accessible Chromatin using sequencing were used to further validate transcriptional changes and to profile alterations in the chromatin accessibility landscape in purified cardiomyocyte nuclei from 21 human donors. Functional validation studies of sex steroids implicated in cardiac maturation were performed in human pluripotent stem cell-derived cardiac organoids and mice.

Results: Our data identify the progesterone receptor as a key mediator of sex-dependent transcriptional programs during cardiomyocyte maturation. Functional validation studies in human cardiac organoids and mice demonstrate that the progesterone receptor drives sex-specific metabolic programs and maturation of cardiac contractile properties.

Conclusions: These data provide a blueprint for understanding human heart maturation in both sexes and reveal an important role for the progesterone receptor in human heart development.
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April 2021

Expression profiling in exercised mdx suggests a role for extracellular proteins in the dystrophic muscle immune response.

Hum Mol Genet 2020 02;29(3):353-368

Murdoch Childrens Research Institute, Royal Children's Hospital, Melbourne 3052, Australia.

Duchenne muscular dystrophy (DMD) is a lethal muscle wasting disorder caused by mutations in the DMD gene that leads to the absence or severe reduction of dystrophin protein in muscle. The mdx mouse, also dystrophin deficient, is the model most widely used to study the pathology and test potential therapies, but the phenotype is milder than human DMD. This limits the magnitude and range of histological damage parameters and molecular changes that can be measured in pre-clinical drug testing. We used 3 weeks of voluntary wheel running to exacerbate the mdx phenotype. In mdx mice, voluntary exercise increased the amount of damaged necrotic tissue and macrophage infiltration. Global gene expression profiling revealed that exercise induced additional and larger gene expression changes in mdx mice and the pathways most impacted by exercise were all related to immune function or cell-extracellular matrix (ECM) interactions. When we compared the matrisome and inflammation genes that were dysregulated in mdx with those commonly differentially expressed in DMD, we found the exercised mdx molecular signature more closely resembled that of DMD. These gene expression changes in the exercised mdx model thus provide more scope to assess the effects of pre-clinical treatments. Our gene profiling comparisons also highlighted upregulation of ECM proteins involved in innate immunity pathways, proteases that can release them, downstream receptors and signaling molecules in exercised mdx and DMD, suggesting that the ECM could be a major source of pro-inflammatory molecules that trigger and maintain the immune response in dystrophic muscle.
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February 2020