Fig. 1

Granuloma stages (I-IV) in tissues from pigs. a Granuloma, submandibular lymph node, pig. Stage IV granuloma with a thick connective tissue capsule, and a prominent caseous necrotic core with multifocal islands of mineralization, accompanied by a satellite stage II granuloma (asterisk), composed by epithelioid macrophages enclosed by a thin capsule, with peripheral infiltration of scattered lymphocytes. Hematoxylin and eosin (HE). Bar, 50 μm. b Granuloma, submandibular lymph node, pig. Multicentric granulomas with several mineralization foci (arrows) as well as extensive necrosis. HE. Bar, 500 μm. c Granuloma, lung, pig. Clustered epithelioid macrophages surrounded by lymphocytes and erythrocytes in a stage I granuloma in the lung. HE. Bar, 50 μm. d Granuloma, liver, pig. Coalescent stage II granulomas (dashed black circles) showing epithelioid macrophages enclosed by a thin connective tissue capsule (dashed white line), with mild peripheral infiltration of scattered lymphocytes. HE. Bar, 50 μm