Study Shows Oral Bacteria Suppression Protects Against Viral Growth

Researchers from the University of Louisville (UofL) School of Dentistry have released a study detailing how proteins produced by cells in the mouth can protect against viral infection. This family of proteins known as interferon lambdas are produced by epithelial cells in the mouth. The study also demonstrated that oral bacteria called Porphyromonas gingivalis can reduce the effectiveness of those protective cells, according to assistant professor Juhi Bagaitkar.

"Our studies identified certain pathogenic bacterial species, P. gingivalis, which cause periodontal disease, can completely suppress interferon production andseverely enhance susceptibility to viral infection," Bagaitkar said in a journal from the University. "These resident oral plaque bacteria play a key role in regulating anti-viral responses."

P. gingivalis has been linked to periodontal disease as well as a variety of other diseases such as Alzheimer’s, rheumatoid arthritis, and esophageal cancer. As the mouth can be an entry point for many viral infections such as COVID-19, and human papillomavirus, this study emphasizes the importance of interferon cells in protective against disease caused by oral bacteria.

This research was helmed by professor and chair of the UofL Department of Oral Immunology and Infectious Disease Richard Lamont, as well as Bagaitkar, Carlos Rodriguez-Hernandez, and other colleagues at UofL and Washington University in St. Louis. The findings were published in December 2021, and the study was supported by the Center of Biomedical Research Excellence.