b2815 Tissue Engineering and Nanotheranostics “9.61x6.69”10 Tissue Engineering and Nanotheranosticsmyocyte phenotype in a culture.^43 MSCs are used in a wide variety of
treatment models, including both injectable and volumetric tissue
engineered deliveries.44,
3.4. Satellite Cells
SCs have been identified as monopotent stem cells that reside along-
side the myofibers in skeletal muscle.^46 These cells can be activated
when there is need for new muscle fiber generation.^47 Following
stimulation, they differentiate into myoblast cells, then fuse into
multinucleated myofibers.^46 Some research has shown that the SCs
will remain in their undifferentiated, inactive state for long periods
until a signal disrupting the stem cell environment such as tissue dam-
age is introduced.^48 Unfortunately, SCs do not maintain their poten-
tial to proliferate or differentiate well in vitro, although with careful
culturing they may prove useful in tissue engineering of volumetric
constructs.42,
4. Engineering Approaches
There is much debate on which cells and approaches should be con-
sidered ideal. One thing that holds true for all treatment options is
that they must all account for the development of myofibers and
motor neurons with adequate blood supply from capillary structures
to be effective replacements for damaged tissue. Tissue engineers
have found that there are many parameters of cell culture that can
alter the behavior of cells. Ideal substrate stiffness and topography,
mechanical stimulation, and electrical stimulation can all be culture
inputs that encourage differentiation, proliferation, or maturation
of many stem cells and somatic cell tissues. Generally, it is accepted
that bioreactors mimicking in vivo conditions can lead cells toward
forming the desired tissues. Because there are many important cell
types in skeletal muscle, it is important to design bioreactors to
encourage development of nerves and vasculature, as well as muscle
fibers. The tissue engineering strategies for attaining muscle growth
can be divided into two main groups, those that develop muscle
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