Figure 1: Shows the consequences of disruption of the blood brain barrier BBB. Thrombin is an example of a protein with pathogen protein associated molecular pattern (PPAMPS) released into the neuropil and its neurotoxic effects are countered by the expression of glial “selfdefence” proteins including the serpins (serine protease inhibitors) protease derived glial-nexins PA-1, PN-1. Systemic T cells are identified and targeted by “Death signals” TNF and CD95L/CD95F as expressed by astrocytes and neurons this initiates apoptosis. Apoptotic cells defined as “altered self” by cell surface apoptotic cell associated molecular patterns (ACAMPs) are identified by microglia expressing pattern recognition receptors (PRR) and subsequently cleared from the brain, reducing the severity of the inflammatory response.