Biological & Soft Matter Seminar: Lipoplex Topology as Modulated by Sirna Electrostatic Pinning

Abstract:

Lipid-nucleic acid complexes (often referred as lipoplexes) are typical examples of a self-assembly process determined by a balance of terms of different nature. Lipid membrane curvature, electrostatic attraction, and DNA stacking are contributions we have been carefully exploring recently. The majority of the lipoplexes are presented as flat lipid layer stacks intercalated with DNA or siRNA that can function as therapeutic entities in the fields of gene delivery and lately gene silencing. Interestingly, the pathway for endosomal escape requires membrane fusion and pore formation events which in Helfrich language translate to high degree of negative Gaussian curvature. Non-Euclidian lipid phases such as bicontinuous cubic fall in this same category of negative Gaussian curvature materials. When selected wisely, lipids can be stabilized as topologically active phases incorporating siRNA and such complexes display remarkable cellular delivery capabilities. We will reveal our most recent efforts to construct bicontinuous cubic lipoplexes and will demonstrate how that topology dictates their functionality in cell culture. 

Seminar Organiser: Jonathan Schwitzer