Fig. 1.

Osteoclastogenesis from bone marrow- and spleen-derived precursors. Bone marrow (BMC) and spleen cells (SC) from FVB mice were cultured overnight with MCSF (25 ng/ml). The following day, non-adherent precursors were plated at 50,000 cells/cm² for bone marrow and 75,000 cell/cm² for spleen cells and treated with MCSF (50 ng/ml) and RANKL (50 ng/ml) for 3–9 days for bone marrow and 3–12 days for spleen cells. Samples were fixed, and stained for TRAP. a, b Representative images of untreated cultures (left) and RANKL-treated cultures (right) generated from bone marrow precursors on day 5 (a) and from spleen precursors on day 9 (b). c, d Changes in average numbers of osteoclasts with time in cultures from bone marrow (c) and spleen (d) precursors. Data are mean ± SE, n = 5–25 experiments