Fig. 4

PEDF-deficiency protects against IL-1β-induced matrix loss in organ cultures of metatarsal bones. a Metatarsal bones from 10 week old wild type or PEDF-deficient mice were harvested and cultured in the presence or absence of 10 ng/mL IL-1β for 7 days. Samples were cryosectioned and stained with Toluidine Blue. Scale bar = 100 μm. b Percent loss of Toluidine Blue staining along the articular surface in 10 week old samples with respect to the total surface area was calculated. c Metatarsal bones from 29 week old wild type or PEDF-deficient mice were harvested and cultured in the presence or absence of 10 ng/mL IL-1β for 7 days. Samples were cryosectioned and stained with Toluidine Blue. Scale bar = 100 μm. d Percent loss of Toluidine Blue staining along the articular surface in 29 week old samples with respect to the total surface area was calculated. For experiments involving either 10 or 29 week old mice, the middle three metatarsal bones isolated from three animals were used. Each data point in the graphs represents an individual metatarsal bone. Each treatment was repeated 5–11 times. Data are plotted as mean ± SEM. ** p = 0.0021 (Mann–Whitney test)