By Chris Mohney From UAB Magazine, Fall 1999 (Volume 19, Number 3)

The idea of attacking cavities via the nose might, to most people, seem bizarre—but that’s exactly the goal of an intriguing research project being conducted at UAB.

Microbiologist Suzanne Michalek, Ph.D., and pediatric dentist Noel Childers, D.D.S., Ph.D., have developed an anti cavity vaccine that’s being administered to volunteers in a nasal spray rather than in a hypodermic needle. The study is now entering its second year, and volunteers are receiving their one-year boosters. When the results are analyzed, Michalek and Childers hope to see the emergence of new techniques for treating not just tooth decay, but a whole array of diseases.

Sniff and Spread

Unlike traditional vaccines, which are injected directly into the bloodstream, the nasal spray vaccine works by way of the mucosal immune system—an antibody-producing “factory” that resides in the body’s mucosal surfaces, such as the lining of the respiratory, digestive, and urogenital tracts. By introducing the vaccine into the mucosal cells lining the nasal passages, Michalek and Childers hope to trigger an immune response that will spread throughout the body’s other mucosal sites, including the mouth.

Previous research has shown that a vaccine administered to a mucosal site can trigger increased production of disease-fighting proteins called immunoglobulin A, or IgA—not only at the site of vaccination, but also at other mucosal sites. This immune response is mediated by special areas of lymphatic tissue such as those in the gut called “Peyer’s patches,” which take up the antigens in the vaccine and distribute them so that, ultimately, antibodies are formed at mucosal sites throughout the body.

Since the vast majority of infectious diseases gain access to the body through mucosal surfaces, nasal spray vaccines hold promise for slowing or even preventing a wide range of illnesses.

Why, then, test out this new strategy on cavities? “Cavities are a well-understood infectious disease that conveniently involves the mucosal immune system,” says Michalek, “so we decided to focus our work on that disease process.”

The target of the vaccine is the bacterium Streptococcus mutans, which colonizes the teeth and causes the buildup of plaque—the substance that leads to cavities, or “caries.” If the new vaccine works as Michalek and Childers expect it to, it will trigger the production of antibodies that prevent S. mutans from binding to the teeth, thus reducing the buildup of cavity-causing plaque.

Foiling a Foothold

Childers says the new vaccine could be a great boon for pediatric patients, since it is during childhood that people are most vulnerable to tooth decay. Childhood also represents a golden opportunity, he says, to keep cavity-causing bacteria from settling in and taking up lifelong “residence” in the mouth.

“Caries is somewhat unique as an infectious disease,” he says. “The oral cavity will be colonized by a variety of bacteria, but if the new vaccine can eliminate S. mutans for a time when the patient is most vulnerable to caries, then other, less harmful bacteria will move in and prevent S. mutans from ever getting a foothold.”

The next step for Michalek and Childers is to actually test the vaccine for its safe use in children. They’ll also be analyzing early results during the next few months, as well as testing new protocols and vaccine variants.

It’s still too early in the study to gauge the vaccine’s overall effectiveness in defeating S. mutans, but if all goes well, it could conceivably become part of the normal battery of childhood vaccines. Although kids might not like the nose spray too much, chances are they’ll gladly choose it over the formidable needles that deliver other vaccines.

				Links to related information: What is Tooth Decay (Caries or Cavities)? Dentistry and Oral Health Dentistry Services at UAB University of Alabama School of Dentistry at UAB
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