JAG2 and active NOTCH1 are detected in lesional LCH cells in situ. (A) LCH cells are the only DCs that coexpress Notch receptor and ligand. RMA normalized expression values for Notch-receptors and Notch-ligands. (B-D) Immunohistochemical analysis of paraffin-embedded LCH material. Sections were stained with Abs to JAG2 (B), full-length NOTCH1 (C), and activated NOTCH1 (D-E). Corresponding isotype controls are shown in supplemental Figure 5B. LCH samples LCH13 (B-C), LCH15 (D), and LCH16 (E) are shown. Immunofluorescence staining of a frozen LCH section showing staining for Langerin (green), DAPI (blue), and activated NOTCH1 (red). (F) Immunoblot analysis showing activated NOTCH1 in biopsy material from LCH patients. MOLT-4 and Jurkat cell lines were used as positive controls. Ponceau staining was used to ensure comparable loading.