title: Cell-mediated drug delivery.
abstract: BACKGROUND
  Drug targeting to sites of tissue injury, tumor or infection with limited toxicity is the goal for successful pharmaceutics. Immunocytes (including mononuclear phagocytes (dendritic cells, monocytes and macrophages), neutrophils and lymphocytes) are highly mobile; they can migrate across impermeable barriers and release their drug cargo at sites of infection or tissue injury. Thus, immune cells can be exploited as Trojan horses for drug delivery.
  
  
  METHODS
  This paper reviews how immunocytes laden with drugs can cross the blood-brain or blood-tumor barriers to facilitate treatments for infectious diseases, injury, cancer, or inflammatory diseases. The promises and perils of cell-mediated drug delivery are reviewed, with examples of how immunocytes can be harnessed to improve therapeutic end points.
  
  
  CONCLUSIONS
  Using cells as delivery vehicles enables targeted drug transport and prolonged circulation times, along with reductions in cell and tissue toxicities. Such systems for drug carriage and targeted release represent a new disease-combating strategy being applied to a spectrum of human disorders. The design of nanocarriers for cell-mediated drug delivery may differ from those used for conventional drug delivery systems; nevertheless, engaging different defense mechanisms in drug delivery may open new perspectives for the active delivery of drugs.
authors.affiliation: Center for Drug Delivery and Nanomedicine, Department of Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, NE 68198-5830, USA. ebatrako@unmc.edu
authors.forename: Elena V
authors.initials: EV
authors.lastname: Batrakova
authors.forename: Howard E
authors.initials: HE
authors.lastname: Gendelman
authors.forename: Alexander V
authors.initials: AV
authors.lastname: Kabanov
mesh_terms: D000818:Animals; D001812:Blood-Brain Barrier / Q000276:immunology / Q000378:metabolism; D002633:Chemotaxis / Q000276:immunology; D004337:Drug Carriers / Q000737:chemistry; D004339:Drug Compounding; D016503:Drug Delivery Systems / Q000379:methods*; D005089:Exocytosis / Q000276:immunology; D006801:Humans; D049329:Nanostructures / Q000737:chemistry; D010586:Phagocytes / Q000276:immunology / Q000378:metabolism; D004364:Pharmaceutical Preparations / Q000008:administration & dosage* / Q000737:chemistry; D013234:Stem Cells / Q000276:immunology / Q000378:metabolism; D013499:Surface Properties
chemical_list: D004337:Drug Carriers; D004364:Pharmaceutical Preparations