title: αEnv-decorated phosphatidylserine liposomes trigger phagocytosis of HIV-virus-like particles in macrophages.
abstract: Macrophages represent an important cellular target of HIV-1. Interestingly, they are also believed to play a potential role counteracting its infection. However, HIV-1 is known to impair macrophage immune functions such as antibody-mediated phagocytosis. Here, we present immunoliposomes that can bind HIV-1 virus-like particles (HIV-VLPs) while being specifically phagocytosed by macrophages, thus allowing the co-internalization of HIV-VLPs. These liposomes are decorated with anti-Env antibodies and contain phosphatidylserine (PS). PS mediates liposome internalization by macrophages via a mechanism not affected by HIV-1. Hence, PS-liposomes mimic apoptotic cells and are internalized into the macrophages due to specific recognition, carrying the previously bound HIV-VLPs. With a combination of flow cytometry, confocal live-cell imaging and electron microscopy we demonstrate that the PS-immunoliposomes presented here are able to elicit efficient HIV-VLPs phagocytosis by macrophages and might represent a new nanotechnological approach to enhance HIV-1 antigen presentation and reduce the ongoing inflammation processes.
  
  
  BACKGROUND
  This team of authors demonstrate that specific phosphatidylserin immunoliposomes are able to elicit efficient phagocytosis of HIV-virus-like particle by macrophages and might represent a new nanomedicine approach to enhance HIV-1 antigen presentation and reduce ongoing inflammation processes.
authors.affiliation: Department of Biology/Molecular Biophysics, Humboldt University Berlin, Berlin, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Gramatica
authors.affiliation: Department of Physics, Free University Berlin, Berlin, Germany.
authors.forename: Roberto A
authors.initials: RA
authors.lastname: Petazzi
authors.affiliation: Department of Biology/Molecular Parasitology, Humboldt University Berlin, Berlin, Germany.
authors.forename: Maik J
authors.initials: MJ
authors.lastname: Lehmann
authors.affiliation: Department of Biology/Molecular Biophysics, Humboldt University Berlin, Berlin, Germany.
authors.forename: Joanna
authors.initials: J
authors.lastname: Ziomkowska
authors.affiliation: Department of Biology/Molecular Biophysics, Humboldt University Berlin, Berlin, Germany.
authors.forename: Andreas
authors.initials: A
authors.lastname: Herrmann
authors.affiliation: Department of Biology/Molecular Biophysics, Humboldt University Berlin, Berlin, Germany,. Electronic address: chiantis@cms.hu-berlin.de.
authors.forename: Salvatore
authors.initials: S
authors.lastname: Chiantia
mesh_terms: D000906:Antibodies / Q000737:chemistry* / Q000276:immunology; D017209:Apoptosis / Q000187:drug effects; D002460:Cell Line; D015686:Gene Products, env / Q000276:immunology; D015658:HIV Infections; D006801:Humans; D008081:Liposomes / Q000737:chemistry* / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects*; D008856:Microscopy, Fluorescence; D010587:Phagocytosis / Q000187:drug effects*; D010718:Phosphatidylserines / Q000737:chemistry*
chemical_list: D000906:Antibodies; D015686:Gene Products, env; D008081:Liposomes; D010718:Phosphatidylserines
keywords: Fluorescence microscopy; HIV-1; Immunoliposomes