Figure 5

Osteosarcoma-derived Sema3A reduces osteotropic activity of KHOS cells. (A) In vivo osteoclast number (Oc.N, left) and osteoclast surface (Oc.S, middle) from tibial metaphysis from mice from the experiment described in Fig. 3. Representative photomicrographs of TRAcP positive osteoclasts indicated with solid arrows from the experiment described are shown on the right. (B) In vitro human osteoclastogenesis in RANKL-stimulated human peripheral blood monocytes co-cultured with human KHOS cells overexpressing Sema3A (Sema3A^OE) or mock control as assessed by TRAcP staining. (C) In vitro mouse and human osteoclastogenesis in RANKL-stimulated human peripheral blood monocytes (left) and mouse bone marrow cells (middle) exposed to conditioned medium from human KHOS cells overexpressing Sema3A (Sema3A^OE) or mock control. Representative photomicrographs of human osteoclasts from the experiment described are shown on the right. (D) In vitro osteoclastogenesis of murine M-CSF- and RANKL-stimulated bone marrow cultures in the presence and absence of Sema3A (300 ng/ml). Representative photomicrographs of mouse osteoclasts from the experiment described are shown in the right. Data are mean ± SEM, n = 3 *p < 0.05, **p < 0.01 ***p < 0.001, ⁺⁺p < 0.01 of mock.