Nanoengineered devices to control cell function by NIR light

The possibility to remotely manipulate intracellular pathways in single cells is among the current goals of regenerative medicine, demanding new strategies to enhance tissue repair and reprogram cycling activities of endogenous stem and differentiated cells. Novel advanced nanomaterials are addressing this need, due to improvements in the controlled synthesis and functionalization of micro/nanostructures. This study aims to achieve spatial-temporal control of an ancient and highly conserved system controlling a variety of developmental and adult processes in all metazoans, from Hydra to mammals, the Wnt/?-catenin signalling pathway. Recently breakthroughs in stem-cell biology highlighted the involvement of Wnt signalling in repair and/or regeneration of many tissues, including skin, bone, neural tissue, myocardium, making the manipulation of this pathway an important therapeutic goal. Here we developed a system to Switch ON this pathway by NIR illumination and demonstrated its bioactivity in vivo by using a simple model invertebrate at base of animal evolution, the freshwater polyp Hydra vulgaris, enabling fast and unequivocal readout of Wnt pathway activation1. An intracellular modulator of the Wnt pathway, enclosed into polyelectrolyte multilayer microcapsules2, was delivered in Hydra tissues by NIR light irradiation and induced forced activation of Wnt signalling. The possibility to remotely manipulate Wnt pathway in single cells by optical switchers open the path to the more ambitious goal to achieve controlled release of multiple agonists/antagonists, to drive endogenous stem cell proliferation/differentiation for tissue healing/regeneration purposes