He did his post-doctoral work at Case Western Reserve University in Cleveland, OH, and obtained his Ph.D. from the University of Rochester, NY. Combs' laboratory works to understand the mechanisms by which immune dysfunction may occur in the brain during Alzheimer's disease. His lab focuses on identifying key points in the activation process of the brain's immune cells, microglia. This approach allows them to determine strategies for altering microglia behavior to promote regeneration and survival rather than inflammatory degeneration during disease.