3D Printed Vaccine Patch Offers Vaccination Without a Shot – Outperforms Needle Jab in Boosting Immunity
By UNIVERSITY OF NORTH CAROLINA AT CHAPEL HILL
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| Scientists at the University of North Carolina at Chapel Hill and Stanford University use 3D printer to produce microneedle vaccine patch that dissolves into the skin to boost immunity. Credit: University of North Carolina at Chapel Hill |
Scientists at Stanford University and the University of North
Carolina at Chapel Hill have created a 3D-printed vaccine patch that provides
greater protection than a typical vaccine shot.
The trick is applying the vaccine patch directly to the skin,
which is full of immune cells that vaccines target.
The resulting immune response from the vaccine patch was 10 times
greater than vaccine delivered into an arm muscle with a needle jab, according
to a study conducted in animals and published by the team of scientists in
the Proceedings of the National Academy of Sciences.
Considered a breakthrough are the 3D-printed microneedles lined up
on a polymer patch and barely long enough to reach the skin to deliver vaccine.
“In developing this technology, we hope to set the foundation for even more rapid global development of vaccines, at lower doses, in a pain- and anxiety-free manner,” said lead study author and entrepreneur in 3D print technology Joseph M. DeSimone, professor of translational medicine and chemical engineering at Stanford University and professor emeritus at UNC-Chapel Hill.
The ease and effectiveness of a vaccine patch sets the course for
a new way to deliver vaccines that’s painless, less invasive than a shot with a
needle, and can be self-administered.
Study results show the vaccine patch generated a significant
T-cell and antigen-specific antibody response that was 50 times greater than a
subcutaneous injection delivered under the skin.
That heightened immune response could lead to dose sparing, with a
microneedle vaccine patch using a smaller dose to generate a similar immune
response as a vaccine delivered with a needle and syringe.
While microneedle patches have been studied for decades, the work
by Carolina and Stanford overcomes some past challenges: through 3D printing,
the microneedles can be easily customized to develop various vaccine patches
for flu, measles, hepatitis, or COVID-19 vaccines.
Advantages
of the vaccine patch
The COVID-19 pandemic has been a stark reminder of the difference
made with timely vaccination. But getting a vaccine typically requires a visit
to a clinic or hospital.
There a health care provider obtains a vaccine from a refrigerator
or freezer, fills a syringe with the liquid vaccine formulation and injects it
into the arm.
Although this process seems simple, there are issues that can
hinder mass vaccination – from cold storage of vaccines to needing trained
professionals who can give the shots.
Meanwhile vaccine patches, which incorporate vaccine-coated
microneedles that dissolve into the skin, could be shipped anywhere in the
world without special handling and people can apply the patch themselves.
Moreover, the ease of using a vaccine patch may lead to higher
vaccination rates.
How
the microneedles are made
It’s generally a challenge to adapt microneedles to different
vaccine types, said lead study author Shaomin Tian, researcher in the
Department of Microbiology and Immunology in the UNC School of Medicine.
“These issues, coupled with manufacturing challenges, have
arguably held back the field of microneedles for vaccine delivery,” she said.
Most microneedle vaccines are fabricated with master templates to
make molds. However, the molding of microneedles is not very versatile, and
drawbacks include reduced needle sharpness during replication.
“Our approach allows us to directly 3D print the microneedles
which gives us lots of design latitude for making the best microneedles from a
performance and cost point-of-view,” Tian said.
The microneedles were produced at the University of North Carolina
at Chapel Hill using a CLIP prototype 3D printer that DeSimone invented and is
produced by CARBON, a Silicon-Valley company he co-founded.
The team of microbiologists and chemical engineers are continuing
to innovate by formulating RNA vaccines, like
the Pfizer and Moderna COVID-19 vaccines, into microneedle patches for future
testing.
“One of the biggest lessons we’ve learned during the pandemic is
that innovation in science and technology can make or break a global response,”
DeSimone said. “Thankfully we have biotech and health care workers pushing the
envelope for us all.”
Reference: “Transdermal vaccination via 3D-printed microneedles induces potent humoral and cellular immunity” by Cassie Caudill, Jillian L. Perry, Kimon Iliadis, Addis T. Tessema, Brian J. Lee, Beverly S. Mecham, Shaomin Tian and Joseph M. DeSimone, 22 September 2021, Proceedings of the National Academy of Sciences.
Additional study authors include Cassie Caudill, Jillian L. Perry,
Kimon lliadis, Addis T. Tessema and Beverly S. Mecham of UNC-Chapel Hill
and Brian J. Lee of Stanford.
Funding: Defense Threat Reduction Agency, Sponsored Research
Agreement from Carbon, Inc., Stanford University Innovative Medicines
Accelerator, Joseph M. DeSimone Start-up Funds at Stanford University