Victory over caries is getting closer
Chinese scientists have demonstrated a vaccine against caries
Sergey Vasiliev, Naked Science
An excess of sweets and poor oral care contribute to the development of caries and the destruction of tooth enamel, which affects up to 90 percent of the population. But the key reason for this is the activity of bacteria that form extremely resistant films on the surface of teeth. The main role in this is played by streptococci Streptococcus mutans, which theoretically may well become objects of a powerful immune attack. Unfortunately, being in the mouth, as part of biofilms, S.mutans antigens almost do not cause an immune response.
Yan Huimin and his colleagues from the Wuhan Institute of Virology are trying to create a vaccine that stimulates such a response. A few years ago, they demonstrated a variant using hybrid proteins. Such molecules contained recombinant PAc antigens from S. mutans bacteria, but carried the C-terminus borrowed from E. coli flagellins (KF). Flagellins cause a strong immune response and were supposed to stimulate the body.
This approach worked: with intranasal injection to laboratory rats, the hybrid vaccine KF-rPAC reduced tooth decay by up to 64 percent. Unfortunately, the same experiments have shown quite unpleasant side effects, including the development of powerful inflammation. To get rid of them, Yan Huimin and co-authors created a hybrid protein of the second generation (KFD2-rPAC), as they write in an article published by the journal Scientific Reports.
Scientists again conducted experiments with laboratory rodents. In animals with healthy teeth, injection of the KFD2-rPAC vaccine slowed their destruction after infection with S.mutans by 64 percent (upper figure), and in animals with already started caries reduced its development by 54 percent (lower figure). At the same time, there are practically no side effects, and Yan Huimin's team continues experiments, trying to get closer to clinical trials of the vaccine.
PBS is a neutral non–immunogenic protein,
control – mice that were not infected with streptococcus (VM).
Portal "Eternal youth" http://vechnayamolodost.ru
21.09.2017