Figure 2. Sections of heterotypic recombination between neural stem cell aggregations and embryonic oral epithelium (A-D), between bone-marrow-derived cells and embryonic oral epithelium (E-H), and between NIH3T3 cell aggregations and embryonic oral epithelium (I-L). (A) Lightfield photomicrograph showing localization of epithelium in a recombinant explant. (B-D) Sections adjacent to (A) showing radioactive in situ hybridization for Lhx7 (B), Msx1 (C), and Pax9 (D). (E-H) Adjacent sections of a recombination between bone-marrow-derived cells and embryonic oral epithelium. (E) Example of GFP expression in embryonic oral epithelium in a recombination. (F-H) Expression of Lhx7 (F), Msx1 (G), and Pax9 (H) in bone-marrow-derived cells adjacent to the embryonic oral epithelium. (I) Lightfield photomicrograph showing localization of epithelium in recombinant explants. (J-L) Sections adjacent to (I) showing no expression of Lhx7 (J), Msx1 (K), and Pax9 (L). Tooth germ epithelium is outlined in red. Scale bar: 100 µm.