FIG. 2.

Mesenchymal condensations in micromass. Bright field (BF) and fluorescent micrographs of a representative micromass culture after 3 days in culture. Top row shows lower magnification images of multiple condensations; scale bar is 200 μm. Bottom row shows higher magnification images of a single condensation; scale bar is 50 μm. (A) In BF images, mesenchymal condensations are recognizable as dark spots. Condensations are further characterized by an increased cell density, visible as bright spots in cultures stained with DAPI (blue) (B), and increased peanut agglutinin lectin (PNA) staining (green) (C). (D) Color micrograph of a representative micromass, cultured for 3 days, stained with Alcian Blue to identify deposition of glycosaminoglycans. Mesenchymal condensations show increased staining intensity. Scale bar is 200 μm. Color images available online at www.liebertpub.com/teb