Figure 3. Levels of anti-P. gingivalis IgG1 and IgG2a in the chambers of immunized IFN{gamma}-/- and IFN{gamma}+/+ mice (n = 6, each group). The animals were immunized by two consecutive injections of heat-killed P. gingivalis in Alum adjuvant, followed, 11 days later, by intra-chamber challenge of P. gingivalis. Exudates were harvested 24 hrs post-challenge. Significant difference between IFN{gamma}-/- and IFN{gamma}+/+ groups (p < 0.05) are indicated by an asterisk.