Can Influenza Vaccines Trigger Immune Response in Patients With Lung Cancer?
Posted: Friday, March 13, 2020
Antipathogen vaccines such as the annual influenza vaccine may be useful not only for infection prevention, but also as a way to change tumor cell microenvironments in the lungs to increase the immune system’s response. Andrew Zloza, MD, PhD, of Rush Medical College in Chicago, and colleagues proposed that repurposing the “flu shot” may improve response rates to immunotherapy and be “quickly translated for clinical care.” Their study findings were published in the Proceedings of the National Academy of Sciences of the United States of America.
“We wanted to understand how our strong immune responses against pathogens like influenza and their components could improve our much weaker immune response against some tumors,” said Dr. Zloza in Rush University press release.
Researchers found that patients who had lung cancer and were hospitalized for a lung infection from influenza lived longer than those who had no history of influenza. This led to their creation of an inactivated flu vaccine, which was directly injected into mouse tumors. Mice were first injected with melanoma cells to localize the tumor to the lung. They were then challenged with active influenza virus. This injection of influenza led to reduced melanoma foci in the lungs.
The team then utilized autologous immune-reconstituted patient-derived xenograft mouse models to surgically transplant primary lung tumors into mice. The 2017–2018 unadjuvanted seasonal influenza vaccine was injected directly into these tumors and was able to reduce the growth of these primary lung tumors. Injection of the influenza virus converted the “cold” tumors to “hot” tumors and generated systemic CD8-positive T-cell responses and sensitized the tumors to checkpoint blockade.
The same type of experiment was done with melanoma. However, the vaccine did not seem to produce the same reduction in growth in melanoma, likely due to the fact that the lungs contain natural cell targets for active influenza infection, and the skin does not, the author suggested.
Disclosure: For full disclosures of the study authors, visit https://www.pnas.org/.