Figure 3

Analysis of proteoglycan loss from cartilage monocultures and co-cultures with SFB. Cartilage monocultures (n = 5, with four replicates each) and co-cultures with SFB (n = 5 patients with four replicates for each patient) with or without stimulation with TNF-α, IL-1β or TNF-α/IL-1β (14 days), as detected by safranin-O staining. (a) The upper panel shows representative histological samples, in which red colour indicates the presence and green colour the absence of proteoglycans in the cartilage matrix. Fresh, non-cultured cartilage serves as a positive control. The lower chart depicts the results of quantitative image analysis of the stained sections. (b) Aggrecanase I/II activity in culture supernatants of cartilage monocultures and co-cultures with SFB (n = 5 with four replicates for each patient). Mean ± standard error of the mean (SEM) are plotted. § p ≤ 0.05 Mann-Whitney U Test compared with non-stimulated control; * p ≤ 0.05 Mann-Whitney U Test compared with stimulation with TNF-α; # p ≤ 0.05 Mann-Whitney U Test compared with stimulation with IL-1β; + p ≤ 0.05 Mann-Whitney U Test compared with cartilage-monoculture.