Nat. Rev. Rheumatol. 5, 667–676 (2009)

In the Review by Hiroshi Takayanagi in the December 2009 issue of Nature Reviews Rheumatology, the effect on osteoclastogenesis of the TH1-cell-associated cytokines IL-12, IL-18 and GM-CSF was incorrectly stated as 'Stimulation' instead of 'Inhibition' in Table 1.