Differences between Mycobacterium-Host Cell Relationships in Latent Tuberculous Infection of Mice Ex Vivo and Mycobacterial Infection of Mouse Cells In Vitro

Figure 9

The cell-to-cell adhesive molecule CD31 on the cells in the fragments of mouse splenic granulomas. The scale bars are (a, left panel) 20 μm and ((a, other panels)-(b)) 10 μm each. (a) Immunochemical localization of CD31 on granuloma cells and control mouse peritoneal macrophages (Mph). The brown color indicates the presence of the receptor in these cells. The black arrows, red arrows, and red stars indicate macrophages, fibroblasts, and dendritic cells, respectively, stained for this marker. (b) Confocal immunofluorescent localization of the cell-surface receptor CD31 (green signal) and the costimulatory molecule CD86 (red signal) on granuloma macrophages. Colocalization of the markers on confocal images of cells (yellow signal). Nuclei are stained by DAPI (blue signal). In the lower-right panel, the same fragment as in the other panels restained for acid-fast BCG-mycobacteria by the ZN method. A CD31-producing macrophage with BCG-mycobacteria reproducing in it is indicated by the white arrows on the fluorescent images and by the black arrow on the ZN image. Abbreviations as in Figure 1.

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