Try new way of applying vaccines using dental thread

Researchers from the State University of North Carolina (United States) have demonstrated a new method of administration of vaccines in an animal model, using tooth thread to introduce the vaccine through the tissue between the teeth and the gums. The tests showed that this new technique stimulates the production of antibodies on mucous surfaces, such as nose and lungs.

“Mucous surfaces are important because they constitute a pathogens such as flu and COVID-19-he explains Harivender Singh GillProfessor of Nanomedicin at the State University of North Carolina and author of the article. However, if a vaccine is administered by injection, antibodies occur mainly in the bloodstream throughout the body, and relatively few on mucous surfaces. “

“But we know that when a vaccine Through the mucosa, antibodies are stimulated not only in the bloodstream, but also on mucous surfaces – he continues. This improves the body’s ability to prevent infections, since there is an additional antibody defense line before a pathogen enters the body. “

This is where the union epithelium comes into play, a thin layer of tissue located in the deepest part of the cavity between the tooth and the gum, and lacks the barrier characteristics present in other epithelial tissues. This absence of barrier It allows the union epithelium to release immune cells to combat bacteria. These immune cells are found in saliva, as well as between teeth and gums.

“Because the union epithelium is more permeable than other epithelial tissues, and it is a mucous layer, it presents a unique opportunity to introduce vaccines into the body, in a way that will stimulate a greater production of antibodies in the mucous layers of the body,” he says Gill.

To determine the viability of administering vaccines through the union epithelium, the researchers applied the vaccine to wax dental and then cleaned the teeth of laboratory mice. Specifically, they compared the production of antibodies in mice that received a peptide vaccine against flu by using dental thread in the union epithelium, the nasal epithelium or the application of the vaccine in the sublingual mucosa.

“We discover that the application of the vaccine through the union epithelium produces an antibody response in the mucous membranes much higher than the current oral vaccination technique, which consists of placing the vaccine under the tongue – he says Rohan Ingrolefirst author of the article, who was a doctoral student with Gill at the Texas Technological University. The dental thread technique also offers comparable protection against the flu virus compared to the administration of the vaccine through the nasal epithelium. “

“This is extremely promising, since most vaccine formulations cannot be administered through the nasal epithelium; the barrier characteristics of that mucous surface prevents efficient absorption of the vaccine –resalta Gill-. The intranasal administration can also cause the vaccine to reach the brain, which can pose security problems. However, vaccination through the union epithelium does not present this risk. For this experiment, we chose one of the few vaccine formulations that really works for the nasal administration because we wanted to compare the administration through the Epitelio de Unión with the best possible scenario for the Nasal Administration. “

The authors of the study, in the magazine Biomedical Engineering They also evaluated the Method effectiveness of administration through the epithelium of union for three other important classes of vaccines: proteins, inactivated viruses and MRNA. In all three cases, the administration technique through the epithelial union produced responses of robust antibodies in the bloodstream and in the mucous membranes.

They also discovered that, at least in the animal model, it did not matter if food and water were consumed immediately after using dental thread with the vaccine: the immune response was the same.

Although the common dental thread is an adequate method to manage the vaccine to laboratory mice, researchers know that it is not practical to ask people to hold the dental thread covered with the vaccine between the fingers. To solve this problem, they used a dental thread stick. This stick consists of a piece of dental thread between two tips that are fastened with a handle.

Specifically, the researchers covered the tooth thread with tooth thread sticks with fluorescent food dye. Subsequently, they recruited 27 participants of the study, explained the concept of applying the vaccine by dental thread and asked them to try to deposit the food coloring in the epithelial junction with a dental thread stick.

“We find that approximately the 60% The dye was deposited in the gum bag, suggesting that dental thread sticks can be a practical method to administer the vaccine to the epithelial union – he affirms Ingrole-. We are optimistic about that work and, depending on our findings, we could move towards clinical trials, “he says Gill

While many questions are still answering before the dental thread technique can be considered for clinical use, researchers believe there could be significant advantages beyond the improved antibody response on mucous surfaces.

“For example, it would be easy to manage and address the concerns that many people have about needle vaccination,” he says Gill-. And we believe that this technique should have a price comparable to that of other vaccine management techniques. “

There are also some disadvantages. For example, this technique would not work in babies and young children who still have no teeth. “In addition, we would need to know more about how and if this approach would work for people who have gum diseases or other oral infections.”