Fig. 2.

Lgr5, Sox9, and CD24 are expressed in the crypts of the small intestine. Lgr5 (a), Sox9 (b), and CD24 (c) are expressed broadly throughout the crypt base, but at varying levels. The difference in expression levels facilitates the isolation of or enrichment for IESCs. Arrows indicate Lgr5^HIGH (a) and Sox9^LOW (b) IESCs. Lgr5 and Sox9 expression is indicated by EGFP in commercially available transgenic mice (a, b), while CD24 expression is shown using an antibody (c). Dotted line indicates basolateral edge of crypt (c). All images are shown at ×1,260 original magnification.