Cal
researchers advance goal of artificial muscles
By
Sharon Tang-Quan
Daily Californian
BERKELEY.
(U-Wire) -- University of California at
Berkeley researchers have taken a significant
step in the development of synthetic muscles.
Scientists
at the Richmond Field Station, an annex
to UC Berkeley's Cell and Tissue Engineering
Laboratory, have found that micropatterned
matrix proteins and topography can be used
to control smooth muscle cell morphology.
Cell
morphology is the branch of biology that
deals with the form and structure of cells.
"As
we learn more about creating synthetic muscle,
the long-term application is to develop
muscle using autologous human cells so that
the muscle can be transplanted back into
humans without fear of rejection,"
UC Berkeley bioengineering graduate student
Ngan Huang, said.
These
synthetic muscles can be used by patients
who experience significant muscle loss due
to injury or to diseases such as muscular
dystrophy.
Polymers
were employed as an easy, inexpensive way
to create stamps, or molds.
"In
this study we used poly(dimethylsiloxane)
stamps to microfluidically pattern strips
of collagen onto glass," said bioengineering
graduate student Rahul Thakar. After examining
the patterns, images of the patterned areas
were captured using phase contrast microscopy.
Researchers
also noticed the bovine aortic SMCs preferentially
aligning parallel to the collagen channels.
Collagen is the fibrous protein constituent
of bone, cartilage, tendon, and other connective
tissue. Tissues that are highly aligned
include muscle. Such a development in provides
the basis for future progress in creating
synthetic muscle.
"Most
cells in the body have a fixed alignment
and orientation. To create engineered tissues
to mimic blood vessels and muscle, it is
important to be able to regulate their structural
alignment to mimic what exists in vivo,"
Huang said.
In
vitro and in vivo experiments study biological
systems out of and in the organism, respectively.
Current
studies on SMC are usually conducted in
unrestricted environments, allowing the
SMCs to grow randomly and without alignment.
Thakar notes that the lab's experiments
provided an organized in vitro system to
study vascular cells' behavior. "The
micropatterned surface allowed the cells
to be cultured in the pattern, and therefore,
be organized," Thakar said.
In
the second part of the experiment, topographical
channels were created on biodegradable biomaterials.
"We
created micron-sized grooves in a thin film
of polylactide-co-glycolide, a biocompatible
and biodegradable polymer," Huang said.
"When we grew smooth muscle cells on
them, we saw similar results as on the collagen-coated
strips on glass."
By
utilizing PLGA, a polymer ideal for tissue
implantation, the study took steps that
will hopefully create an engineered blood
vessel, in which SMCs are aligned in a similar
fashion to the human body according to Ho.
This research is the first study to focus
on the effects of morphology on SMC functions.
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