# Identifying Angiocrine Factors for Cardiomyocyte Maturation Using Single-Cell Sequencing

> **NIH NIH K99** · STANFORD UNIVERSITY · 2020 · $162,432

## Abstract

PROJECT SUMMARY
Induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) currently generated in culture suffer from a
major limitation of cellular immaturity, unable to recapitulate the phenotypes of the adult cardiomyocytes. No
single method to date has been accepted as the ‘gold standard’ in achieving cellular maturity of iPSC-CMs. To
address this critical limitation of iPSC-CM technology, I will identify growth factors secreted from developing
coronary vessel cells that regulate myocardial compaction during cardiac development. I will then test whether
the identified factors can robustly enhance iPSC-CM maturation using various functional phenotyping techniques.
Specifically, in Aim 1 (K99), I will perform single-cell RNA-seq on embryonic hearts to uncover the interplay
between coronary vessel endothelial/endocardial cells and cardiomyocytes. Using the state-of-the-art
bioinformatics pipelines for intercellular communication analysis, I will identify a set of angiocrine factors secreted
from developing coronary vessels predicted to augment cardiomyocyte maturation. In Aim 2 (K99), I will test the
direct effects of the identified factors on cardiomyocyte maturation, by exogenously treating the factors to
explanted embryonic hearts ex vivo and to human iPSC-CMs in vitro. I will employ various functional phenotyping
methods to assess the level of cellular maturity after the treatment of the factors. Lastly in Aim 3 (R00) I will use
single-cell RNA-seq and ATAC-seq to unveil the transcriptomic and epigenetic information of the maturation
process of iPSC-CMs at the single-cell level. The completion of this R00 aim will allow me to determine key
transcription factors regulating iPSC-CM maturation, to identify subpopulations of cells resistant or conducive to
maturation protocol, and to generate cellular trajectory of iPSC-CM differentiation and maturation.
My K99 training will be guided by an exceptional team of mentors and advisory committee whom will provide
support and mentorship in all phases of my transition to independence. During the K99 phase I will engage in
two externships to further develop technical skills and conceptual knowledge in electrophysiology and single-cell
epigenetics. With my existing expertise in single-cell sequencing and the proposed training opportunities, I
foresee no major obstacles in completing the proposed experiments. The K99/R00 award will thus propel me to
realize my longstanding career goal of becoming an independent investigator in cardiovascular research and to
continue making impactful discoveries in our field.

## Key facts

- **NIH application ID:** 9870806
- **Project number:** 1K99HL150216-01
- **Recipient organization:** STANFORD UNIVERSITY
- **Principal Investigator:** David T Paik
- **Activity code:** K99 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $162,432
- **Award type:** 1
- **Project period:** 2020-02-01 → 2022-01-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9870806

## Citation

> US National Institutes of Health, RePORTER application 9870806, Identifying Angiocrine Factors for Cardiomyocyte Maturation Using Single-Cell Sequencing (1K99HL150216-01). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/9870806. Licensed CC0.

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