Sensitive, non-immunogenic imaging of cancer metastases and immunotherapy response.

Non-invasive imaging of tumors expressing reporter transgenes is a popular preclinical method for studying tumor development and response to therapy due to its ability to distinguish signal from tumors over background noise. However, the utilized transgenes, such as firefly luciferase, are immunogenic and, therefore, impact results when expressed in immune-competent hosts. This represents an important limitation, given that cancer immunology and immunotherapy are currently among the most impactful areas of research and therapeutic development.