Non-Invasive Quantification of Vaccine-mediated Antigen Delivery to Lymph Node by Magnetic Resonance Imaging
Hyam Levitsky, professor of Oncology at the Johns Hopkins Sidney Kimmel Comprehensive Cancer Center, serves as the principal investigator for a third project that is developing a noninvasive monitor for the effectiveness of vaccines for cancer and infectious diseases. Vaccines deliver antigen molecules to antigen presenting cells, such as dendritic cells that teach the immune system to remember and react to harmful pathogens or cancer cells that contain those antigens. Currently however, vaccine efficacy is limited by how much of the injected antigen is captured and delivered to lymph nodes by appropriately activated antigen presenting cells. By labeling vaccines with supraparamagnetic iron oxide (SPIO)—nanosized particles that can be imaged with magnetic resonance imaging (MRI)—the team is creating a noninvasive, visual way to quantitatively track, in real time, how effectively a vaccine delivers its antigen in a living organism, providing a window into the immune response that can quickly evaluate strategies seeking to amplify the response. Jeff Bulte, professor of radiology at the School of Medicine, is co-investigator on this project.
“One of the key bottlenecks limiting vaccine efficacy is how much of the injected antigen finds its way to appropriately activated antigen presenting cells,” Levitsky said. “Novel vaccine adjuvants are being developed that impact on the efficiency of this process, and while they are likely to have a profound impact, there is no way to evaluate their relative effectiveness, short of doing large randomized clinical trials. The current nanotechnology developed in this project has the potential to vastly accelerate this process.”