A novel liposomal cellular model, complexed with extracellular matrix.

In order to implement numerous biochemical reactions such as metabolic functions in artificial cells, it is necessary to secure a cell-like closed space that can maintain its shape during signal transduction and biological reactions. However, most liposomes are easily burst by changes in osmotic pressure or external physical stimuli, so it is very difficult to maintain a biochemical reaction in a cell-like space. By making phospholipid liposomes bound with extracellular matrix (ECM), it was possible to generate stable liposomes despite rapid changes in osmotic pressure or external physical stimuli. We found that the negatively charged portion of phospholipid vesicles can selectively recruit ECM proteins to form a protein network on the surface of giant unilamellar vesicles (GUVs). Liposomes bound to the extracellular membrane matrix (ECM) have the properties of a new phospholipid with improved mechanical and physical properties so that they do not rupture even in complex biochemical processes like real cells. Depending on the extracellular matrix (ECM) bound to the outside of the liposome (collagen, fibronectin, and laminin), each liposome model showed different structural stability to internal biochemical changes, potentially serving as a new liposome model to build more complex artificial cells.