Immunopathology of Postprimary Tuberculosis: Increased T-Regulatory Cells and DEC-205-Positive Foamy Macrophages in Cavitary Lesions
Figure 1
Granuloma histopathology. (a) Typical caseating granuloma, with central necrosis flanked by epitheliod cells and foamy macrophages. The periphery of the granuloma consists of lymphocytes, 100x. (b) Langhan’s giant cell, 400x. (c) Abundant CD4+ cells in the granuloma include both lymphocytes and macrophages, 100x. (d) CD8+ cells were mainly located in the periphery of the granuloma, 100x. (e) B-cells, identified by the CD20 stain, were noted in the outer layer of the granuloma. (f) Granulomas stained heavily for the CD68 marker, 100x. (g) Macrophages at the periphery of the granuloma stain positive for the dendritic cell marker DEC-205, 400x. The insert demonstrates a digitally zoomed region to detail the DEC-205 staining. (h) T-regulatory cells, identified by the Foxp3 marker (arrow), were found in the lymphocytic layer of the granuloma, 400x. (i) CD31 stain shows well-vascularized tissue at the periphery of the granuloma, 200x.
