For the first time, researchers have shown that using a nanovaccine to deliver cancer immunotherapy can slow tumor growth and prolong survival in mouse models of several types of cancer. Share on Pinterest Researchers found that the nanovaccine slowed tumor growth and prolonged survival in numerous mouse models of cancer. This image shows how a solution of the nanoparticles scatters laser light.

Image credit: UTSW The team – from the University of Texas Southwestern (UTSW) Medical Center in Dallas – describes the work in the journal Nature Nanotechnology. Immunotherapy is a way of treating disease by getting the body’s immune system to fight it. When that disease is cancer, it is “critically important” that the immunotherapy generates immune cells called T cells that can recognize and target tumor cells for elimination. One way to do this is to apply the principle of a vaccine, where antigens – molecules that uniquely identify the target – are delivered to the immune system to prime it to recognize and destroy the disease-causing cells. Co-senior author Jinming Gao, a UTSW professor of pharmacology and otolaryngology, says that various established vaccine approaches – such as using live bacteria as the delivery mechanism – have been used in cancer immunotherapy. However, he notes that these tend to be complex and costly, and they can also result in immune-related side effects.

‘Minimalist nanovaccine’ takes antigen to lymph nodes The approach that the UTSW researchers have developed – which they describe as a “minimalist nanovaccine” – comprises a simple mixture of a tumor antigen and a synthetic polymer nanoparticle. Nanoparticles are being increasingly used in medicine as they allow scientists to manipulate materials at the level of individual atoms, which is a very useful scale for tackling disease inside cells. A significant advantage of UTSW’s nanovaccine approach is that the nanoparticles take the antigen directly to the lymph nodes to help generate primed T cells. Prof. Gao says that conventional vaccines do not do this – they require the immune cells to collect the antigens in a “depot system” first and then transport them to the lymph nodes to prime the T cells. For the vaccine to work, it has to first deliver the antigens into a type of immune cell called an antigen-presenting cell. The antigen-presenting cells process and present the antigens for recognition by the T cells.