Prophylactic administration of sclerostin antibody to CIA mice has no effect on clinical scores and systemic inflammation. Two groups of male DBA/1 mice were sensitized to collagen type II to induce arthritis. One group were treated with vehicle (collagen-induced arthritis (CIA) + PBS; n = 15) and the other group received 10 mg/kg sclerostin antibody (Scl-AbI) (CIA + Scl-AbI; n = 15). PBS or Scl-AbI were injected subcutaneously once weekly until termination of the experiment (day 55). (A) Incidence (reported as percentage of animals involved) and (B) clinical score of arthritis were assessed daily and are displayed as mean ± SEM. (C, D, E) Bar plots ± SEM represent serum concentrations of anti-CII immunoglobulins IgG1, IgG2a and IgG2b respectively in each group. Serum from age-matched healthy control mice (CTR; n = 6) were analysed for baseline levels of anti-CII antibodies. Differences between clinical scores were analysed by Mann-Whitney test. The one-way ANOVA test with Tukey's post hoc comparison was used for statistical evaluation of the serum concentration results shown in the bar plots. *P < 0.05 for the difference versus CTR.