Fig. 2

Cathepsin K and RANK gene expression analysis. qPCR analysis of Cathepsin K mRNA (a) and RANK mRNA (b) expression in monocytes differentiated to osteoclasts for 14 days in presence of serum from axSpA patients (n = 11) and healthy donors (n = 10). Addition of the exogenous rhRANKL boosted, independently of M-CSF, osteoclastogenesis which was significantly higher in cultures with axSpA sera (in comparison the control sera), as assessed by Cathepsin K mRNA expression (a) (*** P = 0.0004, mean values: 3.752 vs. 5.957). Supplementation of the culture media with rhM-CSF and/or rhRANKL did not influenced RANK mRNA expression, which was dependent only of axSpA patients sera admixture. axSpA or Healthy – sera obtained from axSpA patients or control blood donors (b). * (P = 0.0491, mean values: 1.096 vs. 2.028; ** P = 0.0018, mean values: 1.258 vs. 2.545; ** P = 0.0017, mean values: 1.081 vs. 2.378 respectively). Data presentation: box = median with interquartile ranges, whiskers – min/max value. Statistics: One-way ANOVA with Tukey’s correction for multiple testing