Microscopic analysis of PO-LN DCs after MMTV(SW) injection.

(A) Semithin section of the outer cortex of the PO-LN at day 6 after MMTV(SW) injection showing a high number of DCs (encircled) around a HEV. The luminal and basal surfaces of the HEV have been marked with a large line. Cells migrating through the HEV have been marked with a fine line. Note the presence of a DC migrating through the HEV. Scale bar = 20 μm. (B) Electron micrograph of an area similar to the box in panel A, showing numerous DCs in the vicinity of a HEV. Note their complex cell surface processes reflecting a highly migratory state. Scale bar = 10 μm. (C) DC in contact with the basal surface of a HEV. Enlargement of an area similar to the box shown in panel B. Scale bar = 5 μm.