Heart failure (HF) after myocardial infarction (MI) is a leading cause of death in
the western world with a critical need for new therapies. A previously developed injectable
hydrogel derived from porcine myocardial matrix (PMM) has had successful results in
both small and large animal MI models. In this study, we sought to evaluate the impact
of tissue source on this biomaterial, specifically comparing porcine and human myocardium
sources. We first developed an analogous hydrogel derived from human myocardial matrix
(HMM). The biochemical and physical properties of the PMM and HMM hydrogels were then
characterized, including residual dsDNA, protein content, sulfated glycosaminoglycan
(sGAG) content, complex viscosity, storage and loss moduli, and nano-scale topography.
Biochemical activity was investigated with in vitro studies for the proliferation
of vascular cells and differentiation of human cardiomyocyte progenitor cells (hCMPCs).
Next, in vivo gelation and material spread were confirmed for both PMM and HMM after
intramyocardial injection. After extensive comparison, the matrices were found to
be similar, yet did show some differences. Because of the rarity of collecting healthy
human hearts, the increased difficulty in processing the human tissue, shifts in ECM
composition due to aging, and significant patient-to-patient variability, these studies
suggest that the HMM is not a viable option as a scalable product for the clinic;
however, the HMM has potential as a tool for in vitro cell culture.