In studies from other groups, RAGE-interacting compoundsefficiently crossed the BBB and robustly increased the brain deliveryof AuNPs by a RAGE-mediated transcytosis.70,71 RAGE is also upregulated in AD and serves as an ‘influx receptor’for Aβ (ref (72) and references therein), suggesting that S100A4 compounds may haveincreased efficiency under AD conditions. Here, S100A4 is linked to Alzheimer disease.