To this end, neutrophils were infected with Porphyromonas gingivalis ATCC 33277, W83, and gingipain-null W83 mutant strain (∆KRAB), and the level of secreted TNF-α, IL-6, and IL-8 in a conditioned media was determined at different time-points after infection. This evidence concerns the gene CXCL8 and infection.