Microbiome Consortium: Microbial Profiling of Human Brain and Gut Microbiomes in Alzheimer’s Disease


Alzheimers disease (AD) is the major cause of dementia in the elderly, thus presenting a significant public health challenge in the United States and worldwide. Although research over the past decades has resulted in a clearer understanding of how the buildup of amyloid beta, tangle pathology and neuroinflammation drive neuronal cell death in AD, the actual events that trigger the disease process, beyond known genetic factors, remains largely unknown. Recent studies suggest additional causal factors like microbial infections and imbalances in the gut bacteria that may contribute to the initial development of AD. We have been examining brain tissue from deceased AD patients and found evidence of microbial genetic material, suggesting the presence of potential infections driving AD brain pathology. We have identified specific bacteria in the brains of patients that are associated with inflammation, as well as respiratory and blood infections. Our objectives in this proposal are to identify the full cadre of microbes in AD brain samples. These findings will address the potential role of infections in causing and driving AD pathology. We will investigate areas within and around the amyloid beta plaque deposits to identify and further explore the link between infection and AD. Additionally, given the established link between imbalances in gut bacteria and brain infections, we will compare the identified brain microbes with gut microbiota in stool samples from AD and non-AD individuals. These studies should enhance our understanding of the role of microbial infections and the gut microbiome in AD, suggesting novel therapies for prevention and treatment. 

Funding to Date



Studies of Alternative Neurodegenerative Pathways, Translational


Rudy Tanzi, Ph.D.

Nanda Kumar Navalpur Shanmugam, Ph.D.