3D Bioprinting Tools Provide New
Avenues for Medical Research
Researchers have developed the tools, materials and protocols for creating living organs, but
cellular complexities still put most printed organs well into the future as research continues.
3D printing is one of the hottest forms of additive manufacturing techniques due to its ability to quickly
and efficiently create custom designs in a
wide range of materials. It became apparent
early on in the development of these
techniques that this methodology would
be appropriate for medical prosthetics.
3D-printed prosthetics can be customized
to the dimensions of specific individuals
and the specialized requirements for each
potential patient. The natural evolution
of this is the 3D printing of biological
constructs—and even artificial organs that
can be implanted—rather than utilizing the
limited availability of donor-sourced medical
transplants.
Numerous conventionally 3D-printed
inert prosthetic components have been
successfully created and implanted over the
past ten years, mostly for medical structural
support applications. These include
vertebrae, mandibles, thoracic cages and
cartilage-based materials such as ears, noses
and trachea.
Alternatively, 3D bioprinting involves
the use of cells to create three-dimensional
living constructs—layer by layer. 3D
bioprinting is still in the early stages of R&D
with numerous techniques, patents and even
the equipment still being developed. The
basic 3D bioprinting process employs a 3D
printer-based deposition of bioinks to create
biologically applicable structures layer by
layer, resulting in a functioning living tissue
or organ.
There are numerous research applications
for these 3D bioprinting tools and processes,
including the development of advanced
bioinks, biosensors, medical constructs,
pills, implants, advanced prosthetics, food
and animal product testing, tissue and organ
generation and dental repairs/replacements.
According to a recent report by market
research firm, Grand View Research, the 3D
bioprinting market (including bioprinter
devices) was estimated at $487 million in
2014 and forecast to grow to $1.8 billion by
2022 for a CAGR of 18% over eight years.
The tools
During the past several years, research
groups have developed a number of 3D
bioprinters for various life science research
investigations. Organovo, San Diego, is the
largest of these—it was the first company to
commercialize the 3D bioprinting of human
tissue with the first cellular blood vessel in
2010. Their NovoGen MMX 3D bioprinter
employs syringe-based extrusion techniques
to produce tissues with 20 or more cell layers
consisting of human cells and nutrient-containing microgels. Organovo produces
human liver tissues with this technology
that it then provides to pharmaceutical
companies for preclinical testing and drug
discovery research (the company does
not market its in-house developed 3D
bioprinter). Organovo also is working with
L’Oreal to develop 3D printed skin. They’re
also working to develop a 3D process for
printing kidney tissues similar to their liver
printing process.
Tokyo-based Cyfuse Biomedical is
developing a 3D bioprinter, Regenova, with
a methodology termed Kenzan which uses
cellular spheroids containing thousands
of cells that are organized and cultured
which then leads to self-organization and
eventually human tissues. They’re working
on a number of tissue applications including
blood vessels (vasculature), digestive and
urinary organs, cartilage, and liver tissues.
Researchers at Aspect Biosystems,
Vancouver, BC, Canada, have developed
a Lab-on-a-Printer technology which
can fabricate 3D printed tissues utilizing
different cells, biomaterials and growth
factors. This allows them to create macro-scale 3D structures that incorporate micro-level details for programming and creating
architecturally and functionally accurate
human tissues. The company also offers
contract testing services for 3D human
tissue models.
Similarly, Ourobotics, Cork, Ireland,
has created the Ourobotics Revolution 3D
bioprinter that can print up to 10 materials
in the same bioprinted structure, which
can theoretically be expanded to any
number of materials. The relatively low-cost
device currently prints a variety of gel-like materials, including collagen, gelatin,
alginates and chitosan and includes a heated
enclosure that allows researchers to incubate
living cells.
Philadelphia, Pa.-based BioBots has also
created a low-cost 3D bioprinter, along with
specially formulated bio-inks. Their 3D
bioprinter utilizes cartridge technologies
similar to those in inkjet printers, which
can build multi-layered tissues with up to
100 mm-resolution. Following printing, the
tissue is cured with a special blue light that
does not damage the living cells. BioBot
bioprinter cartridges contain three powders
that are mixed with a fourth binding factor
powder and the living cells. The mixture is
then pushed through a syringe onto a tissue
culture dish where the blue light is applied.
Traditional 3D printer company, Rokit,
South Korea, recently announced that it
will expand its product line to include an
in situ 3D bioprinter. Rokit is collaborating
with the Korean Institute of Science and
Technology, Seoul National Univ., Bundang
Hospital, Hanyang Univ. and the Korea
3D bioprinting involves the
use of cells to create three-
dimensional living constructs
