Researchers from the University of Louisville School of Dentistry and their colleagues have discovered details of how proteins produced by oral epithelial cells protect humans against viruses entering the body through the mouth. They also found that oral bacteria can suppress the activity of these cells, increasing vulnerability to infection.

A family of proteins known as interferon lambdas produced by epithelial cells in the mouth serve to protect humans from viral infection, but the oral bacteria Porphyromonas gingivalis reduces the production and effectiveness of those important frontline defenders.

Dr. Juhi Bagaitkar and Dr. Richard Lamont, professor and chair of the UofL Department of Oral Immunology and Infectious Disease, led the work, with first author Carlos J. Rodriguez-Hernandez and other colleagues at UofL and at Washington University in St. Louis. The findings were published in December in PNAS.