Response of neutrophil chemotaxis by anaerobe peridontal bacterial products

Aim. Human neutrophils constitute the first defense barrier against bacteria. Bacteria produce some molecules with chemotactic power. Interactions between these products and neutrophils in early infection phases are not wholly understood at present. The aim of this study was to evaluate neutrophil reaction to soluble bacterial products originating from periodontal anaerobic bacteria (Peptostreptococcus micros, Fusobacterium nucleatum, Eikenella corrodens, Porphyromonas gingivalis [P.gingivalis] and Tannerella forsythensis). Methods. Human neutrophils were obtained from the buffy-coat of heparinized human peripheral blood from healthy volunteers. To measure the human neutrophils chemotaxis, we used the Boyden chamber. After having quantifying the bacterial suspension by real time polymerase chain reaction, ten-fold serial dilutions in RPMI/FBS 1% from 106 to 102 colony-forming units were prepared and used to evaluate the chemotaxis rate. Results. Our results show that the response of human neutrophils to bacterial products generates lower chemotactic responses than to IL-8 and that P.gingivalis bacterial products inhibit neutrophil migration compared with other bacterial soluble products. This low response is to be related to protease presence in P.gingivalis bacterial products that cut the chemotactic proteins. Conclusion. These preliminary results evidence the different bacterial products capacity of modulates the neutrophils motility. We demonstrated that ability of P.gingivalis bacterial products to inhibit neutrophil chemotaxis. This activity makes a crucial role of P. gingivalis, compared to other oral anaerobes, in the periodontal disease