Redirecting Cytomegalovirus Immunity Against Solid Tumors

CMV has a huge impact on the balance of our immune systems, even if we are healthy. As an example, 10-20% of all our T cells can be dedicated to this one virus, highlighting CMVs role in disrupting immune homeostasis. Since >50% of all Americans are infected with CMV, we postulated that if we could redirect this huge pool of T cells to combat cancer it may serve as a general approach for immunotherapy. We found that in mice with pancreatic tumors that are extremely refractory to common therapies, activating these CMV T cells resulted in them being recruited to pancreatic tumors at extremely high levels (e.g. ~80-90% of all CD8 T cells in the tumor are specific for CMV). These CMV T cells can then kill tumor cells, reshape the tumor environment and curb tumor growth. Taken together, we believe this is a new therapeutic approach to fight therapy-resistant pancreatic tumors by repurposing our antiviral CMV T cells to invade them and mediate potent anti-cancer immune responses.