FIG. 5.

Inhibitory effects of IgG antibodies on hemoglobin binding by P. gingivalis. Whole-cell extracts of P. gingivalis ATCC 33277 (30 μg), immobilized on the membrane, were incubated with IgG (4 μg/ml) against whole cells of P. gingivalis ATCC 33277, rKGP_cd, rRGP_cd, fimbriae, and combinations of these and then incubated with human hemoglobin (0.4 mg/ml) at 4°C for 3 h. The densitometric values are expressed as percentages of those obtained with PBS (100%). The experiments were performed twice in triplicate, and the values are expressed as means and standard deviations.