Fig. 6

Breaking resistance to autoimmune arthritis by brushing with P. gingivalis. a Nine B6.DR1 mice which had not developed arthritis at 76 days post CIA challenge (green vertical line) were used for this experiment. Five mice (red squares) were brushed daily for 7 days (shaded pink area) with P. gingivalis and four mice (blue circles) were left untreated. ^‡Paw index is calculated as average number of inflamed paws per arthritic mouse. ^§Severity index calculated as average severity per arthritic mouse. b TRAP staining of knee joints from P. gingivalis-treated and untreated mice. Magenta staining identifies TRAP⁺ osteoclasts. ^¶ p < 0.05 by Student’s t test. Results expressed as average ± SEM (Color figure online)