Human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) are now widely employed to dis- cover the mechanisms of heart diseases and identify potential drug targets. A challenge for current iPSC- CM applications, however, is how to identify and promote functionally mature myocytes that can more faith- fully recapitulate human adult cardiomyocyte characteristics. To propel the next stage of discoveries, there is a critical need for methods that can derive mature iPSC-CM that can accurately model adult heart dis- ease phenotypes, but current efforts are hampered by a dearth of molecular markers that can serve as sur- rogate readouts of iPSC-CM functional maturity. Accordingly, the goal of the present F32 fellowship proposal is identify protein markers that can re- flect the status of in vitro functional maturation of human iPSC-CMs. iPSC-CMs gradually acquire functional- ly mature characteristics following prolonged periods in culture. We recently discovered 190 membrane- protein-encoding genes that are significantly induced at the transcript level in iPSC-CMs after prolonged (30-90 days) of culturing in vitro. Here I will test the hypothesize that a subset of these prolonged culture signatures (PCS) represent bona fide maturity markers of human cardiomyocytes and thus may be har- nessed to isolate functionally mature iPSC-CMs. To achieve this goal, I propose two specific aims:
In Aim 1 I will employ high-resolution mass spectrometry to determine genes which are enriched in culture and in adult hearts at the protein-level, and which can potentially distinguish and isolate functionally mature sub- populations.
In Aim 2 I will verify protein expression of the candidate markers at the single-cell level, and further evaluate the functional characteristics of iPSC-CMs isolated using protein markers, to compare the functional maturity and homogeneity of the acquired iPSC-CMs against current standards. The anticipated payoff of the proposed experiments will be an improved molecular understanding of iPSC-CM functional maturity in culture, which may lead to methods to isolate more mature iPSC-CM popu- lations that can be used for disease modeling studies. These goals are significant in my opinion because they have the potential to greatly improve current iPSC-CMs applications and open doors to development of engineering approaches to further enhance iPSC-CM production. At the same time, the proposed research training plan will also provide valuable training opportunities in stem cell biology (with Sponsor Dr. Joseph Wu) and single-cell analysis (with Co-Sponsor Dr. Garry Nolan), which will complement my existing exper- tise in proteomics and aid me in my future goal of setting up an independent research group in cardiovascu- lar medicine.
Induced pluripotent stem-cell derived cardiomyocytes (iPSC-CM) are routinely used in the laboratory to un- derstand heart disease mechanisms and identify patient-specific drug response. This project aims to identify cell-surface markers of functionally mature iPSC-CM subpopulations using large-scale approaches. The re- sults may advance techniques to derive iPSC-CM and improve the accuracy of modeling adult heart dis- eases, and are therefore relevant to public health.
|Olmeta-Schult, Felicia; Segal, Lauren Massa; Tyner, Sam et al. (2018) NextGen VOICES: Research resolutions. Science 359:26-28|
|Lau, Edward; Wu, Joseph C (2018) Omics, Big Data, and Precision Medicine in Cardiovascular Sciences. Circ Res 122:1165-1168|
|Lee, Andrew S; Inayathullah, Mohammed; Lijkwan, Maarten A et al. (2018) Prolonged survival of transplanted stem cells after ischaemic injury via the slow release of pro-survival peptides from a collagen matrix. Nat Biomed Eng 2:104-113|
|Lau, Edward; Cao, Quan; Lam, Maggie P Y et al. (2018) Integrated omics dissection of proteome dynamics during cardiac remodeling. Nat Commun 9:120|