title: Targeted detection of phosphatidylserine in biomimetic membranes and in vitro cell systems using annexin V-containing cubosomes.
abstract: In this work we have formulated Annexin V (ANX) decorated phosphatidylserine containing phytantriol (PSPhy) cubosomes to act as probes for the enhanced detection of apoptotic membranes in both model and in vitro cell systems. Small angle X-ray scattering (SAXS) and cryogenic-transmission electron microscopy (Cryo-TEM) indicated that ANX-containing PSPhy (ANX-PSPhy) cubosomes retain the Pn3m cubic symmetry and cubic phase nanoparticle characteristics of PSPhy cubosomes. The interaction of ANX-PSPhy cubosomes with apoptotic model and cellular membranes was also investigated using both quartz crystal microbalance with dissipation and confocal microscopy which confirmed that ANX-PSPhy cubosomes can selectively bind to apoptotic cells and model membranes. Neutron reflectometry has also been used to show strong binding of ANX-PSPhy cubosomes to a model apoptotic membrane, and in addition reveals changes in both the bilayer structure and in the internal structure of the cubosome in a region adjacent to the membrane as a result of material exchange. This material exchange between cubosome and apoptotic model bilayer was further demonstrated using Cryo-TEM. We have demonstrated that lipid bound protein, in this case Annexin V, can be used to target cubosome systems to biological surfaces in vitro.
authors.affiliation: Materials Science and Engineering, CSIRO, Bayview Avenue, Clayton, VIC 3168, Australia. hsin-hui.shen@monash.edu
authors.forename: Hsin-Hui
authors.initials: HH
authors.lastname: Shen
authors.forename: Vanessa
authors.initials: V
authors.lastname: Lake
authors.forename: Anton P
authors.initials: AP
authors.lastname: Le Brun
authors.forename: Michael
authors.initials: M
authors.lastname: James
authors.forename: Anthony P
authors.initials: AP
authors.lastname: Duff
authors.forename: Yong
authors.initials: Y
authors.lastname: Peng
authors.forename: Keith M
authors.initials: KM
authors.lastname: McLean
authors.forename: Patrick G
authors.initials: PG
authors.lastname: Hartley
mesh_terms: D017304:Annexin A5 / Q000737:chemistry; D017209:Apoptosis; D032701:Biomimetics / Q000379:methods*; D015374:Biosensing Techniques; D002470:Cell Survival; D006367:HeLa Cells; D006801:Humans; D050866:Liquid Crystals / Q000737:chemistry; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D010718:Phosphatidylserines / Q000737:chemistry*; D058525:Quartz Crystal Microbalance Techniques
chemical_list: D017304:Annexin A5; D010718:Phosphatidylserines
keywords: Apoptosis; Biosensor; Confocal microscopy; Lipid; Liquid crystal; Surface analysis