TABLE 6.

Hydrogen peroxide levels in cell extracts

Extract sourceMean ± SD (n = 4) H2O2 concn (μM)
HEp-2 cells4.58 ± 2.67
HEp-2 cell-conditioned media1.39 ± 0.16
P. gingivalis cells16.6 ± 1.6
P. gingivalis-conditioned media0.0
HEp-2 cell- plus P. gingivalis-conditioned media9.0 ± 1.37
HEp-2 cell-adherent P. gingivalis5.48 ± 1.6