(Figure 3. Recellulerization process using human iPS-cell derived derived
multipotential cardiovascular progenitors (MCPs))
3D Bioprinting Tissue Enginering to Tackle Organ Donor Shortage
In the last 25 years, tissue enginering and regenerative medicine have captured a
large attention from the public and stimulated imagination of physicians, scientists and
enginers to push the frontier of this field. The emergence of stem cell science was
heralded by the description of embrynoic stem cells first in mice and then in humans.
Coupled with the clonal creation of “Dolly” the sheep it underscored a new understanding
of the developmental biology and wound repair that could be applied to creating tissue
and organs. Regenerative medicine utilizing tissue manufacturing has been a creative
topic of study, offering promise for resolving the gap between insufficient organ supply
and transplantation needs (Wikiel et al., 2014).
Development of clinically functional bio-printed organs that can be transplanted
and then physiologically integrate with the recipient patient requires advancements in
three related technologies. First we need better understanding of cell biology and
development of biotechnology to secure adequate populations of clinically functional
cells. Then advancements in bio-printing processes are needed that allow creation of 3D
conformations of cells and biomaterials that more closely mimic the natural organ
function. Finally we need to be able to integrate the bio-synthesized organ to function and
perform in vivo, i.e., in the patient (Moreno et al., 2012).
As we look toward the future, the prospect of using a patient’s own cells to
develop living models of their active biochemistry as well as functional, life-lasting
cellular implants offers potentially revolutionary changes to research and healthcare.
Stem cell biologists are uncovering exciting new ways to induce pluripotency (Yang et al.,
2014).
The major obstacle for heart engineering requires a resource of heart cells, such
as CMs (cardiomyocytes), SMCs (smooth muscle cells), ECs (endothelial cells), CFs
(cardiac fibroblasts) and a 3D heart scaffold that allows the seeded cells to attach,
assemble, synchronize, and form 3D structures. Currently, a variety of synthetic matrices
and natural-derived biomatrices have been developed and widely utilized for tissue
engineering. However, such matrices normally have a uniform composition and are lack
of 3D architecture as well as microniches in the native heart. This issue has prevented 3D
bioprinting technology to move any further (Lund et al., 2013).
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