TNF and Alzheimer disease: However, since TNF-α and Interferon-γ expression were elevated in brains with Braak Stage 3–4 but not Braak 6 AD, and higher percentages of the inflammatory mediators were up-regulated in CSF as compared with brain or VF, conceivably the activation of neuro-inflammation occurs early in the course of AD, but as disease progresses, neuroinflammation subsides or is suppressed.