Engineered PRINT(®) nanoparticles for controlled delivery of antigens and immunostimulants.

Particle replication in non-wetting templates (PRINT) is a novel nanoparticle platform that provides compositional flexibility with the ability to specify size and shape in formulating vaccines. The PRINT platform also offers manufacturing and cost advantages over traditional particle technologies. Across multiple antigen and adjuvant formulations, robust antibody and cellular responses have been achieved using PRINT particles in mouse models.

High-throughput phagocytosis assay utilizing a pH-sensitive fluorescent dye.

We describe a development of a novel high-throughput phagocytosis assay based on a pH-sensitive cyanine dye, CypHer5E, which is maximally fluorescent in an acidic environment. This dye is ideally suited for the study of phagocytosis because of the acidic conditions generated in the intracellular phagocytic vesicles after particle uptake. Use of CypHer5E-labeled particles results in greatly reduced background from noninternalized particles and makes the assay more robust.