US EPA

Linking in vitro-to-in vivoToxicity Testing Using Genetically-matched Organoids and Mice from a Novel Genetic Reference Population

EPA Grant Number: R835802C002
Subproject: this is subproject number 002 , established and managed by the Center Director under grant R835802
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
Center: Organotypic Culture Models For Predictive Toxicology Center
Center Director: Rusyn, Ivan
Title: Linking in vitro-to-in vivoToxicity Testing Using Genetically-matched Organoids and Mice from a Novel Genetic Reference Population
Investigators: Threadgill, David W.
Institution: University of North Carolina at Chapel Hill , Texas A & M University
EPA Project Officer: Klieforth, Barbara I
Project Period: June 1, 2015 through May 31, 2019
Project Amount: Refer to main center abstract for funding details.
RFA: Organotypic Culture Models for Predictive Toxicology Center (2013) RFA Text |  Recipients Lists
Research Category: Human Health , Health , Safer Chemicals

Objective:

One of the long-standing challenges for toxicity testing and chemical safety evaluation is increasing throughput by using in vitro assays while at the same time improving the predictive power through in vitro-to-in vivo extrapolation (IVIVE) of exposure risk. Reprogramming of somatic cells into induced pluripotent stem cells (iPSC) permits generation of embryoid bodies (EB) with beating cardiomyocytes and complex cellular compositions similar to that found in vivo, making them a functional organotypic culture model (OCM). Importantly, iPSC-derived cardiomyocytes recapitulate phenotypic characteristics of cardiac disorders, which suggest that they have the potential to accurately represent individual chemical sensitivity when produced from a genetically heterogeneous population such as the innovative Collaborative Cross (CC) mouse genetic reference population. Overall, we reason the EB-OCM based on the CC is a perfect complement to human iPSC-derived cardiomyocytes for exploring predictive toxicity screening of environmental chemicals and evaluating risk assessment accuracy in a system where endpoints of in vitro OCM and in vivo individuals is known. Thus, the long-term objective of this research proposal is to identify characteristics of in vivo OCM assays that are most predictive of in vivo response to validate the OCM for IVIVE.

Approach:

The central hypotheses of this proposal are that: (i) genetic variation influences how mouse iPSC-derived EB-OCM respond to insult; (ii) analyses using the CC population can be used to uncover genetic and transcriptional networks that control cardiotoxic responses; and (iii) discoveries using in vitro OCMs are predictive of in vivo cardiotoxic responses. This Project will conduct population-based concentration-response high-content/- throughput in vitro screening of up to 200 ToxCast chemicals in mouse iPSC-derived EB-OCM 96 CC strains. In addition, we will collect molecular data to inform IVIVE. Furthermore, by using the unique characteristics of the CC population, molecular readouts, and data from human iPSC-derived cardiomyocytes from Project 1, we will directly test the ability of the EB-OCM to predict cardiotoxicity in genetically matched mice, and the ability of EB-OCM measures for risk assessment in an independent population of exposure naïve CC mice.

Expected Results:

This project will develop and validate a population-based mouse EB-OCM for characterizing susceptibility and variability in cardiac toxicity. In addition, we will map EBOCM- derived phenotypes onto an adverse outcome pathway for cardiotoxicity that will support an evaluation of the accuracy of IVIVE.

Publications and Presentations:

Publications have been submitted on this subproject: View all 1 publications for this subproject | View all 14 publications for this center

Supplemental Keywords:

cardiovascular, stem cells, toxicity pathway, variability, IVIVE

Progress and Final Reports:

2015 Progress Report

Main Center Abstract and Reports:

R835802    Organotypic Culture Models For Predictive Toxicology Center

Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
R835802C001 High-throughput Hazard, Dose-response and Population Variability Assessment of Cardiotoxicity in a Human Induced Pluripotent Stem Cell (iPSC)-derived in vitro Culture Model
R835802C002 Linking in vitro-to-in vivoToxicity Testing Using Genetically-matched Organoids and Mice from a Novel Genetic Reference Population
R835802C003 A Pipeline for in vitro-to-in vivo Extrapolation, Population Modeling, & Prioritization