Study Shows that Gum Disease Bacteria Selectively Disarms Immune System
In a new study, University of Pennsylvania researchers showed that the bacteria responsible for many cases of periodontitis create an imbalance with a two-pronged attack of the human immune system. This imbalance is known as dysbiosis. This discovery opens up new targets for periodontal treatment and also suggests a bacterial strategy in other diseases involving dysbiosis, they noted. Their findings are reported in the journal Cell Host & Microbe (June 11, 2014, Vol. 15:6, pp. 768-778).
The idea, known in ecology as a keystone species, suggests that, although P. gingivalis may be relatively few in number in the mouth, their presence exerts a pull on the overall microbial ecosystem larger than its presence. Indeed, the team has shown that, although P. gingivalis is responsible for instigating the process that leads to periodontitis, it cannot cause the disease by itself.
What this means in the mouth is that so-called “bystander” gum bacteria aren’t cleared by the immune system, promoting dysbiosis and leading to the bone loss and inflammation that characterizes periodontitis. At the same time, breakdown products produced by inflammation provide essential nutrients that “feed” the dysbiotic microbial community. The result is a vicious cycle in which inflammation and dysbiosis reinforce one another, exacerbating periodontitis
Not only will this discovery open up new targets for disease treatment, it conjointly suggests a microorganism strategy that would be at play in alternative diseases involving dysbiosis.