Cathelicidin promotes inflammation by enabling binding of self-RNA to cell surface scavenger receptors

Abstract Under homeostatic conditions the release of self-RNA from dying cells does not promote inflammation. However, following injury or inflammatory skin diseases such as psoriasis and rosacea, expression of the cathelicidin antimicrobial peptide LL37 breaks tolerance to self-nucleic acids and triggers inflammation. Here we report that LL37 enables keratinocytes and macrophages to recognize self-non-coding U1 RNA by facilitating binding to cell surface scavenger receptors that enable recognition by nucleic acid pattern recognition receptors within the cell. The interaction of LL37 with scavenger receptors was confirmed in human psoriatic skin, and the ability of LL37 to stimulate expression of interleukin-6 and interferon-β1 was dependent on a 3-way binding interaction with scavenger receptors and subsequent clathrin-mediated endocytosis. These results demonstrate that the inflammatory activity of LL37 is mediated by a cell-surface-dependent interaction and provides important new insight into mechanisms that drive auto-inflammatory responses in the skin

Nanopatterns Produced by Directed Self-Assembly in Block Copolymer Thin Films

For the last 30 years, block copolymers (BCP) have held the promises of new functional nanomaterials due to their fascinating spontaneous spatial organization as well as their complex properties, combining those of the individual blocks. The pathway is long, starting at the first synthesis mastered in the 1950s [1], travelling through full thermodynamics descriptions [2], the discovery of industrially viable synthesis technologies [3], and the first patents in one of the expected most appealing applicative fields [4]. This path still has obstacles and challenges ahead before block copolymer nanostructures really come out of the research laboratories. Until then, and for many more years, BCPs will keep researchers busy and amazed by their capacities to spontaneously produce chemically and topographically patterned surfaces [5]...