Dottorato in MEDICINA MOLECOLARE

Titolo della tesi: The protein corona of lipid nanosystems: from structure to physiological response

In the last few years, many efforts have been made in the research fields of nanoparticle-based therapeutics approaches for drug and gene delivery. In this context, liposomal platforms represent very promising systems. Indeed, they are biocompatible, have structural features that allow the encapsulation of molecules with different physical-chemical properties and offer protection to the encapsulated agents from degradative processes. Despite their peculiarities, once injected into the systemic circulation, liposomes acquire a new biological identity as a result of a competition between different biological molecules to adsorb on their surface and form an outer layer, referred to as "protein corona" (PC). As protein adsorption appeared to be inevitable, in this Ph. D. work, we provided a deeper understanding of the dynamics that take place to nanoparticles in complex physiological environments. Firstly, we studied liposome-corona complexes in terms of structural properties, composition and interactions with peripheral blood mononuclear cells (PBMCs) in whole blood. Based on this, we investigate the evolution of liposome-protein complexes as a function of protein concentration. To this end, we employed cationic (CL), neutrally charged (NL) and anionic (AL) liposomes as model systems of gene delivery systems. Then, we investigated and characterized the behaviour of a multicomponent liposomal formulation as a gene delivery system. Taken together, our results confirmed the peculiar key role of the PC in affecting the properties of the nanoparticle-protein complexes. Finally, we presented two PC's unusual interpretations and their implication for future finely target delivery and diagnostic applications. Firstly, we proposed an alternative strategy, i.e. pre-coat nanomaterials with an artificial PC that naturally shuttle to the desired cells upon contact with the bloodstream. All our findings pointed out that prior coating could endow the nanomaterials with a target-specific interaction, specifically by acting on the pre-coating composition it could promote or repress the interaction with the immune system cells. Lastly, we presented some experiments on personalized PC and their implication for diagnostic applications. We proposed a blood test for a new pancreatic cancer diagnostic technology based on the nano-bio-interactions between Graphene Oxide (GO) nanoflakes and blood samples. Globally, we contributed to a detailed knowledge about NP-corona systems for both therapeutic and diagnostic purposes and our findings may help accelerate the clinical translation of NPs from bench to bedside.