The body’s natural immune defense plays a critical role in combating pathogens. We seek to understand the critical molecular and cellular underpinnings of who is at risk for infection, how the immune system responds to microbes, and how microbes evade these defenses which can inform how to recruit host factors to improve outcomes. For example, we are working to understand how pathogens as diverse as HIV, Neisseria gonorrhoeae, and SARS-CoV-2 evade neutralizing antibody recognition and clearance, which can inform vaccine design. Meanwhile, acute infections can have debilitating long-term consequences, with the mechanisms behind such post-infection sequelae being poorly understood. For example, we are delineating the relationships between Epstein-Barr virus and host B cells to elucidate how EBV infection, latency and reactivation and the ensuing host response to understand any relationship between EBV infection and the pathogenesis of multiple sclerosis.