Production and Characterization of Liposomes Made of Red Blood Cells

Liposomes are spherical artificial lipid membrane systems largely used for in vivo delivery of active drugs and biomolecules. The most common procedure to avoid an immune response from the host organism is the functionalization of their surface with Polyethylene Glycol (PEG) molecules (Stealth® technology). However, recent reports indicate an increasing number of patients showing a negative reaction to PEG-ylated liposomes, including an immune response to PEG. Since patients with this response may not benefit from future liposome-based treatments, the development of an alternative approach is critical. To address this issue, we propose using Red Blood Cells to prepare liposomes capable of evading the immune response and carrying active drugs in their inner cavity. To do this, we used sheep Red Blood Cells as a starting material and prepared liposomes by extrusion. The characterization of the liposomes was done by Dynamic Light Scattering, microscopy, and fluorescence spectroscopy. Our work showed uniform liposomes can be prepared from host-derived cells and loaded with drug simulators by employing both passive and active loading approaches. These findings may constitute a turning point in the development of liposomes for delivery of bioactive molecules to organisms while alleviating the problems associated with immune responses