Microbubbles have enabled progress in ultrasound imaging and drug delivery by serving as contrast agents that provide molecular-level information on targeted biomarkers. However, their large size (1-10 micrometers in diameter) limits their ability to leave the bloodstream, restricting their effectiveness to well-vascularized tissues.
In contrast, the new 50-NM GVs can penetrate tissues, reaching important immune cell populations in lymph nodes. This capability opens new possibilities for imaging and delivering therapies to previously inaccessible cells. The research was published in the journal Advanced Materials.
Key features and applications
- Penetration and targeting: The 50-NM GVs can reach immune cells in lymph nodes, suggesting their potential use in immunotherapies, cancer prophylaxis, early diagnosis, and infectious disease treatment.
- Electron microscopy insights: Images of lymphatic tissue show clusters of these nanostructures inside cells that activate the innate immune response, highlighting their potential in new therapeutic approaches.
"This breakthrough opens new avenues for ultrasound-mediated disease treatment, impacting future medical practices and patient outcomes. The research has notable implications for treating cancers and infectious diseases, as lymph-node-resident cells are critical targets for immunotherapies," said study author George Lu, assistant professor of bioengineering and a Cancer Prevention and Research Institute of Texas Scholar.
The study involved genetic engineering, nanoparticle characterization, electron microscopy, and ultrasound imaging to analyze the distribution and acoustic response of the 50-NM GVs.
"The rationale was to harness their small size and acoustic properties for biomedical applications," Lu said. "This work represents a pioneering design of functional gas-filled protein nanostructures small enough to cross into the lymphatic system."
