Activation of invariant Natural Killer T lymphocytes in response to the α-galactosylceramide analogue KRN7000 encapsulated in PLGA-based nanoparticles and microparticles

Int J Pharm. 2012 Feb 14;423(1):45-54. doi: 10.1016/j.ijpharm.2011.04.068. Epub 2011 May 14.

Abstract

Invariant Natural Killer T (iNKT) cells have potent immunostimulatory activities that could be exploited for human therapies. The high-affinity CD1d antigen α-galactosylceramide analogue KRN7000 (KRN) activates a cascade of anti-tumor effector cells and clinical studies have already had some initial success. To improve the efficacy of the treatment, strategies that aim to vectorize KRN would be valuable. In this study, we intended to characterize and compare the effect of KRN encapsulated in poly(lactic-co-glycolic acid) (PLGA)-based nanoparticles (NPs, 90nm) and microparticles instead of macroparticles (MPs, 715nm) on the iNKT cell response. Our data show that whatever the size of the particles, vectorized KRN induced potent primary activation of iNKT cells in vitro and in vivo. We show that endocytosis of PLGA-based particles by dendritic cells is mediated by a clathrin-dependent manner and that this event is important to stimulate iNKT cells. Finally, we report that KRN vectorized in NPs and MPs exhibited different behaviours in vivo in terms of iNKT cell expansion and responsiveness to a recall stimulation. Collectively, our data validate the concept that KRN encapsulated in PLGA-based particles can be used as delivery systems to activate iNKT cells in vitro and in vivo.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigen Presentation / immunology
  • Antineoplastic Agents / administration & dosage
  • Antineoplastic Agents / immunology
  • Antineoplastic Agents / pharmacology
  • Cell Proliferation / drug effects
  • Clathrin / metabolism
  • Coculture Techniques
  • Dendritic Cells / drug effects
  • Dendritic Cells / immunology
  • Dendritic Cells / metabolism
  • Drug Carriers / chemistry
  • Endocytosis / drug effects
  • Endocytosis / immunology
  • Galactosylceramides / administration & dosage*
  • Galactosylceramides / immunology*
  • Galactosylceramides / pharmacology
  • Interferon-gamma / blood
  • Interferon-gamma / metabolism
  • Interleukin-2 / metabolism
  • Interleukin-4 / blood
  • Interleukin-4 / metabolism
  • Killer Cells, Natural / immunology
  • Killer Cells, Natural / metabolism
  • Lactic Acid / chemistry
  • Leukocytes, Mononuclear / drug effects
  • Leukocytes, Mononuclear / immunology
  • Leukocytes, Mononuclear / metabolism
  • Liver / cytology
  • Liver / immunology
  • Lymphocyte Activation / drug effects
  • Lymphocyte Activation / immunology*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Microscopy, Electron, Transmission
  • Microspheres*
  • Nanoparticles / chemistry*
  • Natural Killer T-Cells / cytology
  • Natural Killer T-Cells / immunology*
  • Natural Killer T-Cells / metabolism
  • Particle Size
  • Polyglycolic Acid / chemistry
  • Polylactic Acid-Polyglycolic Acid Copolymer
  • Spleen / cytology
  • Spleen / drug effects
  • Spleen / immunology
  • Static Electricity
  • Surface Properties

Substances

  • Antineoplastic Agents
  • Clathrin
  • Drug Carriers
  • Galactosylceramides
  • Interleukin-2
  • Polylactic Acid-Polyglycolic Acid Copolymer
  • Interleukin-4
  • Polyglycolic Acid
  • Lactic Acid
  • Interferon-gamma
  • KRN 7000