Preferential expression of necdin in HSCs. (A) Ndn expression in distinct subsets of hematopoietic cells. Ndn expression was quantified by quantitative PCR assay in each subset of hematopoietic cells as indicated in the graph. Levels of Ndn expression were normalized to an internal control (Hprt) gene. Expression of Ndn is shown calculated relative to Ndn expression in CD34^−/low KSL cells. (B-C) Localization of necdin in HSCs. Freshly isolated CD34^−/low KSL cells (B) or CD34⁺ KSL cells (C) were stained with anti-necdin (green), anti–β-actin (red), and TO-PRO3 (nuclei, blue).