Lipid nanotube networks: Biomimetic Cell-to-Cell Communication and Soft-Matter Technology

The exchange of information on the molecular level is a vital task in metazoan organisms. Communication between biological cells occurs through chemical or electrical signals in order to initiate, regulate and coordinate diverse physiological functions of an organism [1]. Typical chemical modes of signaling and communication are cell-to-cell interaction in the form of release of small molecules by one, and receptor-controlled uptake by another cell, also transport of molecules through gapjunctions [2], and transport via exosome carriers [3]. During the last decade a new mode of intercellular crosstalk has been discovered, and over time firmly established [4]. Thin tubular structures composed of lipid membrane material and actin polymer, which facilitate the selective transfer of membrane vesicles and organelles, have been identified as cell-bridging channels between cells [5]. The structures, known as membrane nanotubes, or tunneling nanotubes (TNT), have become the focus of a growing research field which generated significant results, as it became apparent that these interconnecting conduits are involved in fundamental mechanism of cell-to-cell communication [6,7]. TNTs have been identified in a variety of cells, including immune cells and neurons. Nanotubes between cells have been shown to form in different ways, for example through membrane protrusions originating from one cell and connecting to another, adjacent cell. The discovery of the membrane nanotubes in vitro in 2004 Mini-Review Article