Autophagosomes are detectable in murine Langerhans cells. (A) Transmission electron microscopy of LCs in a bulk epidermal cell suspension from C57BL/6 mice, either freshly isolated (right panel) or cultured for 3 days (left and center panels). The inset image in the right panel highlights a Birbeck granule (arrow). (B) Close-up micrographs of autophagic structures corresponding to the boxes in the low-power overview micrographs. 1 and 3 appear to be limiting membranes of incipient autophagy; 2 and 4 show double membrane-limited autophagosomes. Scale bars: 1 µm (A); 500 nm (B).