title: Preparation, characterization, and safety evaluation of poly(lactide-co-glycolide) nanoparticles for protein delivery into macrophages.
abstract: Following infection, HIV establishes reservoirs within tissues that are inaccessible to optimal levels of antiviral drugs or within cells where HIV lies latent, thus escaping the action of anti-HIV drugs. Macrophages are a persistent reservoir for HIV and may contribute to the rebound viremia observed after antiretroviral treatment is stopped. In this study, we further investigate the potential of poly(lactic-co-glycolic) acid (PLGA)-based nanocarriers as a new strategy to enhance penetration of therapeutic molecules into macrophages. We have prepared stable PLGA nanoparticles (NPs) and evaluated their capacity to transport an active molecule into the human monocyte/macrophage cell line THP-1 using bovine serum albumin (BSA) as a proof-of-concept compound. Intracellular localization of fluorescent BSA molecules encapsulated into PLGA NPs was monitored in live cells using confocal microscopy, and cellular uptake was quantified by flow cytometry. In vitro and in vivo toxicological studies were performed to further determine the safety profile of PLGA NPs including inflammatory effects. The size of the PLGA NPs carrying BSA (PLGA-BSA) in culture medium containing 10% serum was ~126 nm in diameter, and they were negatively charged at their surface (zeta potential =-5.6 mV). Our confocal microscopy studies and flow cytometry data showed that these PLGA-BSA NPs are rapidly and efficiently taken up by THP-1 monocyte-derived macrophages (MDMs) at low doses. We found that PLGA-BSA NPs increased cellular uptake and internalization of the protein in vitro. PLGA NPs were not cytotoxic for THP-1 MDM cells, did not modulate neutrophil apoptosis in vitro, and did not show inflammatory effect in vivo in the murine air pouch model of acute inflammation. In contrast to BSA alone, BSA encapsulated into PLGA NPs increased leukocyte infiltration in vivo, suggesting the in vivo enhanced delivery and protection of the protein by the polymer nanocarrier. We demonstrated that PLGA-based nanopolymer carriers are good candidates to efficiently and safely enhance the transport of active molecules into human MDMs. In addition, we further investigated their inflammatory profile and showed that PLGA NPs have low inflammatory effects in vitro and in vivo. Thus, PLGA nanocarriers are promising as a drug delivery strategy in macrophages for prevention and eradication of intracellular pathogens such as HIV and Mycobacterium tuberculosis.
authors.affiliation: National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada.
authors.forename: Anne-Sophie
authors.initials: AS
authors.lastname: Guedj
authors.affiliation: National Research Council of Canada, Ottawa, ON, Canada.
authors.forename: Arnold J
authors.initials: AJ
authors.lastname: Kell
authors.affiliation: National Research Council of Canada, Ottawa, ON, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Barnes
authors.affiliation: National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada.
authors.forename: Sandra
authors.initials: S
authors.lastname: Stals
authors.affiliation: Laboratoire de recherche en inflammation et physiologie des granulocytes, Université du Québec, INRS-Institut Armand-Frappier, Laval, QC, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Gonçalves
authors.affiliation: Laboratoire de recherche en inflammation et physiologie des granulocytes, Université du Québec, INRS-Institut Armand-Frappier, Laval, QC, Canada.
authors.forename: Denis
authors.initials: D
authors.lastname: Girard
authors.affiliation: National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, MB, Canada.
authors.forename: Carole
authors.initials: C
authors.lastname: Lavigne
mesh_terms: D000818:Animals; D019380:Anti-HIV Agents / Q000008:administration & dosage*; D000893:Anti-Inflammatory Agents / Q000737:chemistry; D017209:Apoptosis; D002460:Cell Line; D002470:Cell Survival; D004337:Drug Carriers / Q000737:chemistry; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007249:Inflammation / Q000188:drug therapy; D019344:Lactic Acid / Q000737:chemistry; D008264:Macrophages / Q000187:drug effects* / Q000382:microbiology; D051379:Mice; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D009169:Mycobacterium tuberculosis; D053758:Nanoparticles / Q000737:chemistry*; D009504:Neutrophils / Q000378:metabolism; D011098:Polyglactin 910 / Q000737:chemistry*; D011100:Polyglycolic Acid / Q000737:chemistry; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D012709:Serum Albumin / Q000737:chemistry; D012710:Serum Albumin, Bovine
chemical_list: D019380:Anti-HIV Agents; D000893:Anti-Inflammatory Agents; D004337:Drug Carriers; D012709:Serum Albumin; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D012710:Serum Albumin, Bovine; D019344:Lactic Acid; D011098:Polyglactin 910
keywords: BSA delivery; HIV reservoir; PLGA nanoparticles; inflammatory profile; murine air pouch; neutrophil apoptosis