Biophysical Society Thematic Meeting - October 25-30, 2015

Polymers and Self Assembly: From Biology to Nanomaterials

Tuesday Speaker Abstracts

Lipid Nanoparticles and Amyloids Activate Receptors of the Innate System Jean-Marie Ruysschaert, Malvina Pizzuto, Caroline Lonez Universite Libre de Bruxelles, Bruxelles, Belgium. Toll-like receptors are major members of the Pattern Recognition Receptors (PRRs) from the innate immune system, which recognize bacterial or viral components. It was recently demonstrated that those receptors, that usually recognized molecular patterns characteristic of pathogens, are activated by non bacterial lipid and protein aggregates (amyloids) structurally different from the natural ligands. We will illustrate this aspect with two examples related to nanoparticles and neurodegenerative diseases. It is tempting to speculate that amyloid fibrils represent a new class of danger signals detected by the innate immune system, through sensing of their common cross-β structure, a motif common to all amyloids irrespective of their origin and sequence.The immune system responds more specifically to structural features of fibrils rather than to an aggregated state or to a specific sequence motif. It is hard to believe that nanoparticles which are so different from natural ligands do activate receptors the same way natural ligands do. How lipid and protein nanoparticles made of a large number of molecules activate pattern recognition receptors is still unknown but it is very likely that it proceeds via a new mechanism quite different from what has been described so far for monomeric natural ligands. Implications in nanotechnologies and nanomedicine will be briefly discussed. 1-Lonez C, Vandenbranden M, Ruysschaert JM.-Adv Drug Deliv Rev. 2012,64,1749-58 2- Lonez C, Bessodes M, Scherman D, Vandenbranden M, Escriou V, Ruysschaert JM. Nanomedicine. 2014 -10(4):775-82-

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