Biomedical Engineering Reference
In-Depth Information
Current Status of Cell Therapy for Cardiovascular Disease
Various types of cells are being used on biodegradables matrices for bioengineering
of the heart. This may provide new treatments for cardiac disorders such as heart
failure and even for replacement of parts of the heart. Bulk of current research is
exploring the role of stem cells in repair and regeneration of the heart. Identification
of multipotent progenitor cells in the heart and better understanding of develop-
mental processes relevant to ESCs may facilitate the generation of specific types of
cells that can be used to treat human heart disease. Secreted factors from circulating
progenitor cells that localize to sites of damage may also be useful for tissue protec-
tion or neovascularization. The discoveries in basic science require rigorous testing
in animal models to determine those most worthy of clinical trials.
Cardiac cell replacement therapy by using hESC-derived cardiomyocytes has
emerged as a promising future approach to regenerate functional myocardium.
However, there are still many hurdles to be overcome for the clinical application of
these cells. A better understanding of the characteristics of the cardiomyocytes
from hESCs not only predicts their behavior after implantation but will also help in
the design of future strategies for cardiac regeneration in vivo.
Allogeneic adult bone marrow-derived hMSCs are emerging as preferred cells
for ameliorating consequences of MI, and have the advantages of ease of prepara-
tion, immunoprivilege, capacity to home to injured tissue, and extensive preclinical
support. A double-blind, placebo-controlled, dose-ranging safety trial has shown
that intravenous allogeneic hMSCs are safe in patients after acute MI (Hare et al.
2009
). Stem cell-treated patients had lower rates of side effects, such as cardiac
arrhythmias. Echocardiography showed improved heart function, particularly in
those patients with large amounts of cardiac damage.
Future Directions for Cell Therapy of CVD
As cell therapy for CVD evolves, some issues need to be resolved (Flynn and
O'Brien
2011
):
•
Although there are no serious adverse effects in clinical trials, this has been in
the setting of the transplanted cells, many of which do not survive beyond a few
hours in the recipient heart. Techniques aimed at prolonging cell survival in the
future may increase risks of arrhythmias or and tumorigenesis. Close monitoring
for adverse events will be essential.
The optimal cell dose, cell type, and timing of administration are uncertain, and
•
determination of these variables is important for realizing the beneficial effect of
cell therapy.
Barriers within damaged myocardium, such as inflammation, fibrosis, and insuf-
•
ficient angiogenesis need to be addressed as this milieu is likely to hinder opti-
mal functional integration of transplanted cells.
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