FIG. 1.

Embryonic skeletal progenitor cells are freshly isolated and cultured in micromass. (A) Photograph of representative stage 23 chicken embryo as used for cell isolations. The red box indicates the location of the limb bud used for cell isolation. Scale bar is 2 mm. (B) Collection of limb buds in phosphate-buffered saline right after dissection. Scale bar is 500 μm. (C) Micrograph of a single cell suspension of freshly isolated chicken limb bud cells, after dissociation. Scale bar is 50 μm. (D) Schematic representation of a micromass; a high cell density drop plated in the center of a culture dish. (E) Bird's eye view of a representative micromass culture after 3 days in culture in a 12-well plate after removal of the culture medium. Scale bar is 5 mm. Color images available online at www.liebertpub.com/teb