These data are supported by the observation that stimulation of skin organ cultures with TNF-α, IL-17, osteopontin, or IL-33, all of which are elevated in psoriasis, resulted in the induction of pro-osteoclastogenic factors, inhibition of anti-osteoclastogenic factors and support the differentiation of monocytes into osteoclast precursors (8). Here, SPP1 is linked to psoriasis.