Fig. 2.

Regional density of AT8 immunoreactive neurofibrillary tangles in CTE stages I–IV. Anti-p-tau antibody (AT8) was used to stain multiple CTE brain regions at different disease stages. In stage I, in addition to isolated perivascular CTE lesions in the cortex, there are sparse neurofibrillary tangles (NFTs) in locus coeruleus but no NFTs in substantia nigra, amygdala or thalamus (case 6). In stage II, in addition to perivascular CTE lesions in the cortex, sparse NFTs are found in the substantia nigra and locus coeruleus (case 12). In stage III CTE, moderate NFTs are found in the substantia nigra, locus coeruleus, amygdala and thalamus (case 19). In stage IV CTE, frequent NFTs are found in the substantia nigra, locus coeruleus, amygdala and thalamus (case 32). All images are ×200 magnification