Fig. 5

a-d Joint histology: comparison of untreated rats (a) and rats treated with dPGS (b) as well of histological scoring results (c, d). Representative frontal cross sections of adult male Wistar rat joints are shown. Depicted is the joint space between femur condyle (top) and the tibia plateau (bottom). Shown are the not surgical destabilized left knees of untreated (a1-3) and treated rats (b1-3). Furthermore, the surgical destabilized right knee of untreated (a4-6) and those of dPGS treated animals (b4-6) are depicted. The tissue was stained using HE (a1, b1, a4, b4), AB (a2, b2, a5, b5) or safranin-O staining (a3, b3, a6, b6). * = meniscus. The regions of interest are labeled by black arrows. Scale bar 200 μm. HE and safranin-O stained paraffin sections of rat knee joints were evaluated using the score systems according to Mankin (1971) (c1, d1) and Glasson et al., (2010) (c2, d2). Depicted are the differences of the left (not surgically altered) and the right knees (surgically destabilized) of all animals (n = 12) (c1-2). Furthermore, the differences between left knees and the right knees for the untreated control and the treated animals are shown separately (d1-2). n = 6 per group. ***p < 0.001