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Ibrahim M Ibrahim,1,2 Aditya N Bade,1 Zhiyi Lin,3 Dhruvkumar Soni,3 Melinda Wojtkiewicz,1 Bhagya Laxmi Dyavar Shetty,1 Nagsen Gautam,3 JoEllyn M McMillan,1 Yazen Alnouti,3 Benson J Edagwa,1 Howard E Gendelman1,31Department of Pharmacology and Experimental Neuroscience, College of Medicine, University of Nebraska Medical Center, Omaha, NE, USA; 2Department of Pharmacology, College of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia; 3Department of Pharmaceutical Sciences, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE, USAPurpose: A palmitoylated prodrug of emtricitabine (FTC) was synthesized to extend the drug’s half-life, antiretroviral activities and biodistribution.Methods: A modified FTC prodrug (MFTC) was synthesized by palmitoyl chloride esterification. MFTC’s chemical structure was evaluated by nuclear magnetic resonance. The created hydrophobic prodrug nanocrystals were encased into a poloxamer surfactant and the pharmacokinetics (PK), biodistribution and antiretroviral activities of the nanoformulation (NMFTC) were assessed. The conversion of MFTC to FTC triphosphates was evaluated.Results: MFTC coated with poloxamer formed stable nanocrystals (NMFTC). NMFTC demonstrated an average particle size, polydispersity index and zeta potential of 350 nm, 0.24 and −20 mV, respectively. Drug encapsulation efficiency was 90%. NMFTC was readily taken up by human monocyte-derived macrophages yielding readily detected intracellular FTC triphosphates and an extended PK profile.Conclusion: NMFTC shows improved antiretroviral activities over native FTC. This is coordinate with its extended apparent half-life. The work represents an incremental advance in the development of a long-acting FTC formulation.Keywords: palmitoyl chloride, viral reservoirs, long-acting antiretrovirals, human immunodeficiency virus type 1, monocyte-derived macrophage

Hardeep S Oberoi,1 Natalia V Nukolova,1,2 Frederic C Laquer,3 Larisa Y Poluektova,4 Jiangeng Huang,1 Yazen Alnouti,1 Masanao Yokohira,5 Lora L Arnold,5 Alexander V Kabanov,1,2 Samuel M Cohen,5 Tatiana K Bronich,1,21Department of Pharmaceutical Sciences and Center for Drug Delivery and Nanomedicine, College of Pharmacy, University of Nebraska Medical Center, Omaha, NE, USA; 2Department of Chemistry, MV Lomonosov Moscow State University, Leninskie Gory, Moscow, Russia; 3Department of Chemistry, University of Nebraska at Omaha, 4Department of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, 5Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USAAbstract: Polymer micelles with cross-linked ionic cores are shown here to improve the therapeutic performance of the platinum-containing anticancer compound cisplatin. Biodistribution, antitumor efficacy, and toxicity of cisplatin-loaded core cross-linked micelles of poly(ethylene glycol)-b-poly(methacrylic acid) were evaluated in a mouse ovarian cancer xenograft model. Cisplatin-loaded micelles demonstrated prolonged blood circulation, increased tumor accumulation, and reduced renal exposure. Improved antitumor response relative to free drug was seen in a mouse model. Toxicity studies with cisplatin-loaded micelles indicate a significantly improved safety profile and lack of renal abnormalities typical of free cisplatin treatment. Overall, the study supports the fundamental possibility of improving the potential of platinum therapy using polymer micelle-based drug delivery.Keywords: cross-linked micelle, cisplatin, ovarian cancer, block ionomer complex, drug delivery

Georgette D Kanmogne1, Sangya Singh1, Upal Roy1, Xinming Liu1, JoEllyn McMillan1, Santhi Gorantla1, Shantanu Balkundi1, Nathan Smith1, Yazen Alnouti2, Nagsen Gautam2, You Zhou3, Larisa Poluektova1, Alexander Kabanov2, Tatiana Bronich2, Howard E Gendelman11Departments of Pharmacology and Experimental Neuroscience, University of Nebraska Medical Center, Omaha, 2Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, NE; 3Center for Biotechnology, University of Nebraska-Lincoln, Lincoln, NE, USAAbstract: Despite the successes of antiretroviral therapy (ART), HIV-associated neurocognitive disorders remain prevalent in infected people. This is due, in part, to incomplete ART penetration across the blood–brain barrier (BBB) and lymph nodes and to the establishment of viral sanctuaries within the central nervous system. In efforts to improve ART delivery, our laboratories developed a macrophage-carriage system for nanoformulated crystalline ART (nanoART) (atazanavir, ritonavir, indinavir, and efavirenz). We demonstrate that nanoART transfer from mononuclear phagocytes (MP) to human brain microvascular endothelial cells (HBMEC) can be realized through cell-to-cell contacts, which can facilitate drug passage across the BBB. Coculturing of donor MP containing nanoART with recipient HBMEC facilitates intercellular particle transfer. NanoART uptake was observed in up to 52% of HBMEC with limited cytotoxicity. Folate coating of nanoART increased MP to HBMEC particle transfer by up to 77%. To translate the cell assays into relevant animal models of disease, ritonavir and atazanavir nanoformulations were injected into HIV-1-infected NOD/scid-γcnull mice reconstituted with human peripheral blood lymphocytes. Atazanavir and ritonavir levels in brains of mice treated with folate-coated nanoART were three- to four-fold higher than in mice treated with noncoated particles. This was associated with decreased viral load in the spleen and brain, and diminished brain CD11b-associated glial activation. We postulate that monocyte-macrophage transfer of nanoART to brain endothelial cells could facilitate drug entry into the brain.Keywords: nanoART, folate, monocyte-endothelial cell interactions, blood–brain barrier, antiretroviral therapy, nanomedicine