Analysis of immunostimulatory activity of Porphyromonas gingivalis fimbriae conferred by Toll-like receptor 2

► FimA fimbriae are an important virulence factor of Porphyromonas gingivalis. ► FimA fimabriae have been reported to stimulate cells via TLR2. ► Degeneration of the protein up-regulated TLR2-mediated TNF-α production in macrophage. ► Enhanced stimulatory activity of the protein was abrogated by lipoprotein lipase-digestion. ► Lipoprotein or lipopeptide may be responsible for the activity of FimA fimbriae.