Fig. 5
SI-613 induced increased production of high molecular weight HA in HFLS-RA and HFLS-OA cells. HFLS-RA cells (a) and HFLA-OA cells (b, c, d) from three donors were separately cultured in [3H] glucosamine and IL-1β with HA or SI-613 at 0.01% (a, b) or 0.1% (c, d) or with PBS for 48 h. Cultures from individual patients were maintained as separate cultures and cells were not pooled. Radiolabeled HA in the culture supernatant was separated using an OH pak SB-807 size exclusion HPLC column (a–c). Each value is from a single HPLC run with a single well. The number of HFLS-OA cells after collection of the culture supernatant was counted (d). Values are represented as the means ± S.E. of three donors. Parametric Tukey’s test was used for statistical analysis. The data from a, b and c were re-analyzed by dividing the fractions into 2 groups with different molecular weight ranges (range I, MW > 2400 kDa; range II, MW = 500–2400 kDa). The fractions eluted later than the 500 kDa MW marker were excluded from the re-analysis because most of the radioactivity in these fractions is derived from free [3H] glucosamine (e). Parametric Dunnett’s test was used for statistical analyses (*P < 0.05, ***P < 0.001)