TB granulomas in IL-2–treated group were less necrotic than those in controls. Histopathology analyses show that control macaques exhibited widespread necrosis, fulminant TB pneumonia, and TB hemorrhage/thrombosis lesions. The alveolar septa are destroyed or indistinct. In contrast, most TB granulomas in lung sections of the IL-2–treated group were well contained and lymphocytic (note the lymphocyte cuff), without widespread necrosis. Original magnification ×100 for all photos. Similar contrasting data were also seen in other controls and IL-2–treated macaques, respectively.