Inflammation, microglia and Alzheimer disease
There is a growing understanding of how microglia shape disease progression in Alzheimer disease. This could aid the development of drugs that enhance the ability of microglia to clear damaged neurons without inducing tissue-damaging inflammation.
Alzheimer disease was once considered to be a neurodegenerative disease as opposed to an inflammatory disorder. However, it is now appreciated that chronic neuroinflammation is a key feature of Alzheimer disease and that microglia, which are the macrophages of the brain, shape disease progression. The Review article “Interplay between innate immunity and Alzheimer disease: APOE and TREM2 in the spotlight” by Yang Shi and David Holtzman discusses how microglia can have protective and harmful roles in Alzheimer disease through their ability to drive waste clearance and inflammation, respectively. In particular, the authors focus on explaining how APOE and TREM2, which are the two strongest genetic risk factors for late-onset Alzheimer disease, shape disease progression through their interaction with microglia. A better understanding of this pathway could lead to new therapies for Alzheimer disease that boost the ability of microglia to clear damaged neurons without amplifying tissue inflammation.
By Yvonne Bordon, Nature Reviews Immunology