Fig. 5.

Cerebral pathology is regulated by TNF but neuron-derived TNF is not required. a–c TNF^f/f, d–f NsTNF^−/− and g–i TNF^−/− mice were infected with M. tuberculosis H37Rv at a dose of 1 × 10³–1 × 10⁴ CFUs/brain by intracerebral inoculation. Haematoxylin and eosin-stained coronal brain tissue sections at 3 weeks post-infection are presented (a, d, g). Ventriculitis of the choroid plexus is primarily lymphocytic in b TNF^f/f and e NsTNF^−/− mice while a predominant neutrophil infiltrate accompanied by necrosis is observed in h TNF^−/− mice. Ziehl–Neelsen staining revealed acid-fast bacilli mainly in the choroid plexus (c, arrow) and ventricular space (f, arrow) in TNF^f/f and e NsTNF^−/− mice while infiltration of bacilli was frequently observed in brain parenchyma (i) in TNF^−/− mice. The granuloma was found in TNF^−/− mouse brain (circle in h, i). Scale bars 20 μm