From the infection experiments of the gingival fibroblasts it became apparent that pro-inflammatory mediators IL-1β, IL-6 and IL-8 expression levels were up-regulated after a 6-hour challenge with both wild-type W83 and the epsC mutant in comparison to the non-infected control, especially when MOIs of 10.000:1 were used. The gene discussed is IL1B; the disease is infection.