The Effects of Extracts from "Red Complex" Pathogens on Human Dental Follicle Cells

Dental follicle cells could be a natural source of cells for regeneration therapies in periodontitis. The "red complex", which include Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia , is strongly associated with periodontitis. However, the effects of "red complex" on dental follicle cells remains largely unknown. In this study, we evaluated the effects of bacterial extracts obtained from Porphyromonas gingivalis and from "red complex" ( Porphyromonas gingivalis, Treponema denticola and Tannerella forsythia in co-culture) on proliferation, migration and osteogenic differentiation of human dental follicle cells. Our data showed that bacterial extracts promoted cell proliferation and migration, decreased the alkaline phosphatase activity, osteogenic genes expression and formation of mineral deposits. Noticeably, compared with the inhibitory effects induced by bacterial extracts from Porphyromonas gingivalis on osteogenic differentiation of human dental follicle cells, the inhibitory effects induced by bacterial extracts from "red complex" were more significant. In conclusion, the extracts from "red complex" pathogens inhibited osteogenic differentiation capacity of human dental follicle cells, and this provides a theoretical basis for the clinical application of stem cell therapy in periodontal tissue engineering.