Figure 3
From: Differential mast cell numbers and characteristics in human tuberculosis pulmonary lesions
Mast cells are observed in granulomas and express IL-17A. Representative micrographs of different types of granulomatous lesions (incipient, mature or necrotic) were stained with HE or with anti-human anti-tryptase or anti-chymase immunoperoxidase antibodies to identify MCT or MCC. (A) Small incipient granuloma. Both MC phenotypes (B) MCT and (C) MCC are detected within the inflammatory area of incipient granulomas. (D) Mature granuloma with central necrosis. (E) MCT and MCC (F) are not infiltrating mature granulomas but both subtypes are observed in the periphery. Micrographs are representative of 11 TB necropsies. Representative section of incipient granuloma was incubated with anti-IL-17A (Alexa 488 label) and anti-tryptase antibodies (Alexa 647 label). (G) Low power micrograph shows numerous IL-17 + cells, and MCT. High power micrograph of the inset shows MCT staining positive for IL-17A.
