Powerful Yet Painless: 3D Printed MucoJet Administers Oral Vaccines

3D printing is often associated with the DIY world, as well as the medical field—and it’s interesting today how the two sometimes meet in surprising ways from orthodontics to prosthetics and casts. In both areas, we’ve seen a continual flow of surprising innovation, allowed by a technology that offers a host of enticing benefits from self-sustainability in creation to affordability, the opportunity to make more lightweight, durable objects, and the list goes on. Globally, we are being introduced to many new processes that just a short while ago were inconceivable.

Continuing in that vein, now we see the DIY and medicine merging as one day patients may be giving their own vaccines. And best of all—they won’t hurt! The 3D printed MucoJet is needle-less and about the same size as a pill. When held against the inside of the cheek, the device sends the vaccine into the mouth via a jet stream. And while the new technology has not yet been tested on humans, researchers at UC Berkeley did have success in giving the vaccines to animals.

The secret to this easy-to-administer vaccine is that it infiltrates an area known as the buccal region, which is plentiful in immune cells. Those cells can often be hard to reach sufficiently, however, due to the thick mucosal layer. The strong—yet painless—jetstream offered by the MucoJet is able to break through the mucosal layer, as a piston pushes the pressurized liquid into the buccal region and causes the desired immune response.

[Photo: Stephen McNally/UC Berkeley]

“The jet is similar in pressure to a water pick that dentists use,” said Kiana Aran.

Aran, now an assistant professor at the Keck Graduate Institute of Claremont University, worked as a postdoctoral scholar in professor of mechanical and bioengineering Dorian Liepmann’s lab, as well as professor of bioengineering Niren Murthy’s lab. All three are authors on a study presenting their research, which was outlined fully in Science Translational Medicine recently. Additional authors included Marc Chooljian, Jacobo Paredes, Mohammad Rafi, Kunwoo Lee, Allison Y. Kim, Jeanny An, Jennifer F. Yau, Helen Chum, and Irina Conboy.

The researchers state that the MucoJet will offer the same strength as a vaccine given by needle. Those requiring vaccines will be able to give it to themselves at home, eliminating the need for traveling to the doctor’s office (often a hassle for babies in need of vaccinations) or administration by someone with a specialized degree. This may also mean a drastic change for citizens in developing countries who need vaccines—especially in very rural areas. The small 3D printed device measures 15 x 7 mm and is composed of two compartments.

[Photo: Stephen McNally/UC Berkeley]

“The MucoJet device used a simple chemical reaction to deliver a jet of vaccine—in this case, ovalbumin—that penetrated the buccal mucosa when placed against the cheek inside the oral cavity in rabbits. The rabbits showed evidence of anti-ovalbumin antibodies in cheek tissue and ear vein blood draws up to 6 weeks after vaccination,” state the researchers in ‘An oral microjet vaccination system elicits antibody production in rabbits.’

“MucoJet has the potential to accelerate the development of noninvasive oral vaccines, given its ability to elicit antibody production that is detectable locally in the buccal tissue and systemically via the circulation.”

MucoJet is able to hold 250 mL of water in the exterior, with one interior compartment serving as the 100 mL vaccine reservoir, and the other serving as the propellant reservoir. The user activates the vaccine by clicking together the compartments, causing the membrane to evaporate and causing a reaction that makes the pressurized carbon dioxide gas. The pistons then deliver a powerful yet painless stream of vaccine into the mouth, targeting the ‘antigen-presenting cells.’

For testing purposes, the researchers first used buccal tissue from pigs. Experimenting in small dishes with mucosal layers and the pigs’ tissue, the team saw an ‘eightfold increase in the delivery of ovalbumin.’ That was in comparison to giving ovalbumin orally with a dropper, which might be how one would take a flu vaccine. The efficacy of the vaccine is accentuated by the power of the Jetstream.

“The pressure is very focused, the diameter of the jet is very small, so that’s how it penetrates the mucosal layer,” said Aran.

The researchers will be testing the vaccine on larger animals soon, and hope to see the device on the market in five to ten years. They may offer a smaller device, ultimately, and perhaps even a lollipop shape for children.

“Imagine if we could put the MucoJet in a lollipop and have kids hold it in their cheek,” said Aran. “They wouldn’t have to go to a clinic to get a vaccine.”

We’ve seen 3D printing come into play before for solutions geared toward enhancing the vaccination experience, but the MucoJet really takes the sting out of the process. Discuss in the MucoJet forum at 3DPB.com.