Researchers at the University of North Carolina at Chapel Hill and North Carolina State University have uncovered a novel approach to creating inhalable vaccines using nanoparticles that shows promise for targeting lung-specific diseases, such as influenza, pneumonia and tuberculosis. 
The work, led by Cathy Fromen and Gregory Robbins, members of the DeSimone and Ting labs, reveals that a particle’s surface charge plays a key role in eliciting immune responses in the lung. Using the Particle Replication in Nonwetting Templates (PRINT) technology invented in the DeSimone lab, Fromen and Robbins were able to specifically modify the surface charge of protein-loaded particles while avoiding disruption of other particle features, demonstrating PRINT’s unique ability to modify particle attributes independently from one another.
When delivered through the lung, particles with a positive surface charge were shown to induce antibody responses both locally in the lung and systemically in the body. In contrast, negatively charged particles of the same composition led to weaker, and in some cases undetectable, immune responses, suggesting that particle charge is an important consideration for pulmonary vaccination.
The findings, published in the Proceedings of the National Academy of Sciences, also have broad public health implications for improving the accessibility of vaccines. An inhalable vaccine may eliminate the need for refrigeration, which can not only improve shelf life, but also enable distribution of vaccines to low-resource areas, including many developing countries where there is significant need for better access to vaccines.
