Representative confocal z-stack of diploid platelet-forming cells (DPFCs) showing proplatelet formation. E10.5 YS CD45⁻CD41^high cells were cultured in serum-free medium with thrombopoietin for 72 hours. Cultures were stained with anti-CD41 and anti-CD42D antibodies. Nuclei were stained with 4,6-diamidino-2-phenylindole (DAPI). Scale bar represents 10 μm. See Figure 1H in the article by Potts et al that begins on page 2725.