Biology subjects

Kowala, A.

Publications and source records attributed to Kowala, A..

3 recordsLinked to original sources

bioRxiv2025

Human Engineered Heart Tissue Models for Pharmacological Studies- Inhibition of Small-Conductance Ca2+-activated K+ (KCa2) channel

Atrial fibrillation (AF) is a common cardiac arrhythmia increasing stroke risk. Current treatments show limited effectiveness and can cause serious side effects. At the moment there is a lack of well-established human models recapitulating complex cardiac microenvironment for studying potential AF therapies. To address the limitations of existing models we developed 3D in vitro human Engineered Heart Tissue (EHT) model using atrial and ventricular human-induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) with either human atrial fibroblasts (HAF) or human ventricular fibroblasts (HVF).These chamber-specific EHTs exhibit differences in gene expression, ion channels and physiological responses, enabling studying Frank-Starling mechanisms and Ca2+ response. Using KCa2 channel inhibitor AP14145, we observed increased contraction force and prolonged relaxation time, suggesting negative modulation of KCa2.2/KCa2.3 channels and increased atrial-effective refractory period (AERP). The EHT model provides a valuable platform for examining KCa2 channel inhibitors impact and evaluating chamber-specific drug effects in controlled in vitro settings.

developmental biology↗

bioRxiv2023

Engineered human myogenic cells in hydrogels generate functional myofibers within dystrophic mouse muscle

Transplantation of human myogenic progenitor cells (MPCs) is a promising therapeutic strategy for treating muscle-wasting diseases, e.g., Duchenne muscular dystrophy (DMD). To increase engraftment efficiency of donor stem cells, modulation of host muscles is required, significantly limiting their clinical translation. Here we develop a clinically relevant transplantation strategy synergising hydrogel-mediated delivery and engineered human MPCs generated from CRISPR-corrected DMD patient-derived pluripotent stem cells (PSCs). We demonstrate that donor-derived human myofibers produce full-length dystrophin at 4 weeks and 5 - 6 months (long-term) post transplantation in the unmodulated muscles of the dystrophin-deficient mouse model of DMD. Remarkably, human myofibers are innervated by mouse motor neurons forming neuromuscular junctions and supported by vascularisation after long-term engraftment in dystrophic mice. PAX7+ cells of human origin replenish the satellite cell niche. There was no evidence of tumorigenesis in mice engrafted with hydrogel-encapsulated human MPCs. Our results provide a proof-of-concept in developing hydrogel-based cell therapy for muscle-wasting diseases.

cell biology↗

bioRxiv2022

CRISPR-mediated correction of skeletal muscle Ca2+ handling in a novel DMD patient-derived pluripotent stem cell model

Mutations in the dystrophin gene cause the most common and currently incurable Duchenne muscular dystrophy (DMD) characterized by progressive muscle wasting. Although abnormal Ca2+ handling is a pathological feature of DMD, mechanisms underlying defective Ca2+ homeostasis remain unclear. Here we generate a novel DMD patient-derived pluripotent stem cell (PSC) model of skeletal muscle with an isogenic control using clustered regularly interspaced short palindromic repeat (CRISPR)- mediated precise gene correction. Transcriptome analysis identifies dysregulated gene sets in the absence of dystrophin, including genes involved in Ca2+ handling, excitation-contraction coupling and muscle contraction. Specifically, analysis of intracellular Ca2+ transients and mathematical modeling of Ca2+ dynamics reveal significantly reduced cytosolic Ca2+ clearance rates in DMD-PSC derived myotubes. Pharmacological assays demonstrate Ca2+ flux in myotubes is determined by both intracellular and extracellular sources. DMD-PSC derived myotubes display significantly reduced velocity of contractility. Compared with a non-isogenic wild type PSC line, these pathophysiological defects could be rescued by CRISPR-mediated precise gene correction. Our study provides new insights into abnormal Ca2+ homeostasis in DMD and suggests that Ca2+ signaling pathways amenable to pharmacological modulation are potential therapeutic targets. Importantly, we have established a human physiology-relevant in vitro model enabling rapid pre-clinical testing of potential therapies for DMD.

cell biology↗