Cardiff University | Prifysgol Caerdydd ORCA
Online Research @ Cardiff 
WelshClear Cookie - decide language by browser settings

Functional characterisation and validation of an in vitro model of Catecholaminergic Polymorphic Ventricular Tachycardia type 1

Bigares, João 2015. Functional characterisation and validation of an in vitro model of Catecholaminergic Polymorphic Ventricular Tachycardia type 1. PhD Thesis, Cardiff University.
Item availability restricted.

[thumbnail of 2016BigaresJPhD.pdf]
Preview
PDF - Accepted Post-Print Version
Download (4MB) | Preview
[thumbnail of 2016BigaresJ_Thesis publication form.pdf] PDF - Supplemental Material
Restricted to Repository staff only

Download (607kB)

Abstract

In the UK alone 28 000 sudden cardiac deaths a year are found to be unrelated to structural heart problems, likely having ion channel malfunction and arrhythmia as an underlying cause. With the discovery of human induced pluripotent stem cells (hiPSC), a new field has emerged, allowing the creation of personalised cellular models of disease that can be studied in vitro. In this study we aim to functionally characterize and validate an in vitro model of Catecholaminergic Polymorphic Ventricular Tachycardia type 1 (CPVT1), an adrenergically elicited arrhythmic condition caused by a mutation in the cardiac ryanodine receptor (S2246L). The cardiac ryanodine receptor (RyR2) is an intracellular ion channel that releases Ca2+ stores essential to cardiac contraction during EC-coupling. Inherited defects in the RyR2 can result in an intracellular calcium leak during diastole that may lead to arrhythmia. The most frequent arrhythmic events at a cellular level in CPVT cardiomyocytes (CM) are delayed afterdepolarizations (DADs) although early afterdepolarizations (EADs) and triggered activity (TA) may also occur. With the need of obtaining a human cell based disease model to establish in vitro valid assays for CPVT study and drug screening, a standardized quantitative approach is ideal. Nonetheless, because the quantitative definition of these arrhythmic endpoints is subjective by nature, most studies using hiPSC CPVT derived CM have assessed these cells only from a qualitative point of view. Using whole cell patch clamp in the ruptured membrane modality and Ca2+ fluorescence imaging, this study aimed to provide a quantitative characterization of arrhythmic endpoints in a CPVT hiPSC model. Pharmacological rescue was carried out using flecainide, propafenone, dantrolene (10μM for all drugs) and propranolol (1μM) in the presence of isoprenaline. Our results show that the average response of hiPSC CPVT CM to recapitulate disease is heterogeneous and therefore not a consistent in vitro model of disease.

Item Type: Thesis (PhD)
Status: Unpublished
Schools: Medicine
Subjects: R Medicine > R Medicine (General)
Funders: Medical Research Council
Date of First Compliant Deposit: 30 March 2016
Last Modified: 01 Mar 2017 02:30
URI: https://orca.cardiff.ac.uk/id/eprint/87325

Actions (repository staff only)

Edit Item Edit Item

Downloads

Downloads per month over past year

View more statistics