YSM Issue 93.1

PRINTING SKIN
PRINTING SKIN
PRINTING SKIN
Biomedical Engineering
FOCUS
Biological tissue is extraordinarily
complex and diverse. Human skin, for
example, guards the muscles, bones,
and internal organs, protects the body
from pathogens, and prevents water
loss. Furthermore, skin is composed
of a variety of cell types, varies in
thickness throughout your body, and is
vascularized, or houses blood vessels.
Developing new biomedical devices to
promote regeneration and healing of
our skin tissue is one of the forefronts of
current medical research.
IMAGE COURTESY OF WIKIMEDIA COMMONS
A vascular graft, an example of a tissue
engineered construct.
The Growth of Tissue Engineering
No matter your interests, you’ve
likely encountered tissue engineering
in one form or another. Cell culturing,
nanofibers, computer aided design, and
bioartificial organs are all used in the
field known as “regenerative medicine,”
a term used synonymously with tissue
engineering. According to the National
Science Foundation, the origins of
tissue engineering
can be traced back
to the late twentieth
century. Since then, the
field has experienced
unprecedented growth,
the volume of research
in the area growing
throughout the 1990’s and
early twenty-first century.
At Yale University, the bulk of
tissue engineering research has emerged
from the biomedical engineering
department, founded in 2003 by W.
Mark Saltzman, Goizueta Foundation
Professor of Biomedical and Chemical
Engineering. Saltzman, in collaboration
with Jordan Pober, Bayer Professor of
Translational Medicine and Professor of
Immunobiology, and Pankaj Karande,
Professor of Chemical and Biological
Engineering at the Rensselaer Polytechnic
Institute (RPI), recently published a paper
in Tissue Engineering in which they
developed vascularized skin graft utilizing
human cells and 3D printing.
On the nature of this longstanding
collaboration, Saltzman said, “We wanted to
take [Pober’s] expertise on endothelial cells
and my expertise on making materials and
combine them to try and find new ways to
make vascular networks in living animals.
That collaboration has been going on for
fifteen years, and we’ve had a lot of success.
This is a start of something new, [and] I
think it will take advantage of everything
we’ve learned and push it in directions that
will become clinically useful.”
by matt spero • art by m il a
The primary author of the paper, Tânia
Baltazar, a Postdoctoral Associate in the
Pober laboratory, studied biology as an
undergraduate and went on to receive a
master’s degree in biotechnology and a
PhD in cell therapy and regenerative
medicine in Lisbon, Portugal.
“Tissue engineering is
very application
driven. You
develop a
c o
product, and
you can see the
impact on the lives
of patients,” Baltazar
said, on why she chose
to pursue the field. “I
wanted to work on a
project that would allow
me to focus on regenerative medicine.”
This project was supported by the
strong collaboration between the two
research groups, as immunology and
engineering came together to form a
single product greater than the sum of its
parts. Though Saltzman studied chemical
engineering as an undergraduate student,
he was not interested in ‘traditional’
chemical engineering careers, such as the
petroleum industry. Instead, he chose to
enroll in a program at MIT and Harvard
Medical School that combined medical
school training with engineering. “There
weren’t a lot of formal programs in
biomedical engineering at the time, but it
gave me a way to use these tools to solve
l i z z a
generating multilayered vascularized human skin grafts
www.yalescientific.org
March 2020
Yale Scientific Magazine
15