(a) mouse 1S/1, granuloma-7 
(b) mouse 23S/2, granuloma-11
(c) mouse 23S/2, granuloma-44
(d) mouse 1S/1, granuloma-14
Figure 2: Granulomas from the spleens (S/) of mice that were infected with BCG vaccine in vivo for one and two months (/1 and/2, resp.) and after ex vivo culture for a few days. Ziehl-Neelsen staining for acid-fast mycobacteria. Scale bars: 50 μm ((b)-(c), left panels, (d), left panel), 20 μm ((a), left panel), 10 μm ((a)–(c), right panels, (d), right panel). Granulomas with different cell types: pictures ((a)–(c), right panels, (d), right panel) are enlarged images of the areas defined by black boxes in pictures ((a)–(c), left panels, (d), left panel), respectively. ((a)–(c)) Macrophages with BCG-mycobacteria are indicated by black arrows. ((b), (d)) Dendritic cells are indicated by black stars. ((b)-(c)) A neutrophil and fibroblasts are indicated by black snowflakes, respectively. The other cells are macrophages without BCG mycobacteria, lymphocytes, and erythrocytes. (a) Macrophages that have migrated from a granuloma. (b)–(d) The monolayer cultures of cells migrated from individual granulomas. (b)-(c) Granulomas with an increased number of macrophages and fibroblasts, respectively. (d) Langhans giant cell in a granuloma. The fusion of macrophage membranes and entry of new macrophage nuclei to the nuclear aggregates of Langhans giant cell.