Narrow Results

In the field of structural DNA nanotechnology, researchers create artificial DNA sequences to self-assemble into target molecular superstructures and nanostructures. The well-understood Watson–Crick base-pairing rules are used to encode assembly instructions directly into the DNA molecules. A wide variety of complex nanostructures has been created using this method. DNA directed self-assembly is now being adapted for use in the nanofabrication of functional structures for use in electronics, photonics, and medical applications.

The use of engineered antigen carriers to optimize the immune response to recombinant subunit vaccines has seen great advances in recent years. Optimization can take several forms, such as facilitating stimulation of certain immune cells or amplifying the adjuvancy effect of the vaccine formulation. In this paper, we applied dose/response analysis to demonstrate the ability of outer membrane vesicle (OMV) antigen carriers derived from engineered Escherichia coli to produce strong antigen-specific immune responses to a model antigen at a significantly decreased antigen load compared to an industry standard alum-based control. Inflammopathology and histological analysis of extended studies further supported a capacity to enhance immune cell recruitment locally at the injection site while decreasing inflammation and eliminating injection site scaring. The results indicate a strong potential for OMV-based vaccines as recombinant antigen delivery vehicles, affording strong immunogenicity at low doses with a broadly applicable platform for recombinant subunit antigen inclusion.

Among the many challenges facing the development of a molecular-based nanotechnology, the directed assembly of discrete molecular objects, and their controlled integration into macroscopic structures, is fundamental. The selective self-assembly or self-organizing characteristic inherent to certain molecules, for example DNA, is a property that could be exploited to address these challenges. This integration problem can be separated into more fundamental tasks: attaching molecular anchors to the macroscopic structures with high spatial resolution; assembling the discrete molecular objects; and positioning and attaching the molecular objects onto the macroscopic structures.

Here, several aspects of these tasks will be discussed, for example using short DNA molecules as molecular anchors and their attachment to electrodes separated by a few ten nanometers; the generation of branched DNA complexes by molecular self-organization; and using AC electric fields for the manipulation, orientation, and positioning of DNA molecules.