Smed-5E12 labels the regeneration blastema. Whole-mount images of intact or regenerating planarians immunostained with 5E12 (green) and counterstained with DAPI (blue) in panel B. (A) 5E12-labeled cells detected throughout the body of an intact animal. (B) 5E12 labels the anterior and posterior blastemas in regenerating trunk fragments stained over the course of 7 days post-amputation (marked by arrowheads), and cells proximal to the regeneration blastemas or throughout the body (marked by arrows at 2–7 dpa). (C) Higher magnification image of 5E12+ cells within a 3 dpa regeneration blastema and posterior to the blastema (arrows). Images in C are maximum intensity projections of optical sections. Anterior is up in all images. Scale bars: (A, B) 200 μm; (C) 50 μm.