Houston: "Guided" human adult stem cells can
effectively heal, repair and regenerate damaged heart tissue,
a Mayo Clinical investigators finding says.
Mayo Clinic investigators, with Belgian collaborators,
have demonstrated that stem cells isolated from patients have
normally a limited capacity to repair.
This innovative technology boosts the regenerative
benefit by programming adult stem cells to acquire a
Primed by a cocktail of recombinant cardiogenic growth
factors, mesenchymal stem cells (MSCs) harvested from the bone
marrow of a cohort of patients with coronary artery disease
showed "superior functional and structural benefit without
adverse side effects" over a 1-year follow-up in a model of
heart failure according to the study.
The findings -- called "landmark work" in an accompanying
editorial -- appear in today`s `Journal of the American
College of Cardiology`.
"These findings provide proof-of-principle that "smart"
adult stem cells have added benefit in repairing the heart,
providing the foundation for further clinical evaluation,"
says Andre Terzic, MD, PhD, Mayo Clinic researcher and senior
investigator of the study.
"The successful use of guided "lineage specified" human
stem cells is based on natural cardiogenic cues" adds Atta
Behfar, MD, PhD first author of the study. The pre-clinical
data reported in this seminal paper have cleared the way for
safety and feasibility trials in humans, which were recently
conducted in Europe.
In their editorial, Eduardo Marban, MD, PhD, and
Konstantinos Malliaras, MD, of Cedars-Sinai Heart Institute,
in Los Angeles describe the Mayo approach as a "boot camp" for
stem cells and also write that the study, "provides the first
convincing evidence that MSCs, at least in vitro, can in
fact become functional cardiomyocytes (heart cells)".
The long-term potential of the findings include
development of an effective regenerative medicine therapy for
patients with chronic heart failure.
Researchers obtained bone marrow-derived stem cells from
heart disease patients undergoing coronary bypass surgery.
Testing of these stem cells revealed that cells from two of 11
individuals showed an unusual capacity for heart repair.
These rare cells demonstrated upregulated genetic
transcription factors that helped identify a molecular
signature identifying highly regenerative stem cells.
The cardiogenic cocktail was then used to induce this
signature in non-reparative patient stem cells to program
their capacity to repair the heart.
Mouse models with heart failure, injected with these
cells, demonstrated significant heart function recovery along
with improved survival rate after a year, compared to those
treated with unguided stem cells or saline.