Optimum conditions for efficient phagocytosis of rifampicin-loaded PLGA microspheres by alveolar macrophages

J Control Release. 2007 May 14;119(1):69-76. doi: 10.1016/j.jconrel.2007.01.013. Epub 2007 Feb 1.

Abstract

We examined the phagocytic activities of alveolar macrophages (NR8383 cells) toward poly(lactic-co-glycolic) acid (PLGA) microspheres (MS) loaded with the anti-tuberculosis agent rifampicin (RFP), the sizes of which were between 1 microm and 10 microm. We found that 1) the phagocytosis was dependent greatly on the particle size and the number of particles added; 2) macrophages phagocytosed considerably the PLGA microspheres loaded with RFP, the diameter of which was between 1 microm and 6 microm, but took up few 10-microm particles; 3) the population of the macrophages that phagocytosed 1-microm or 3-microm particles was larger than that of those phagocytosed 6- or 10-microm particles; 4) a considerable population of macrophages were not able to phagocytose even the 1- and 3-microm particles; 5) the most efficient deliveries of RFP into each macrophage cell and a large population of macrophages were achieved by the phagocytosis of 3-microm particles; and 6) phagocytosis did not affect macrophage viability in 4 h after the start of phagocytosis.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Survival / drug effects
  • Cell Survival / physiology
  • Drug Carriers
  • Lactic Acid / administration & dosage*
  • Lactic Acid / pharmacokinetics
  • Macrophages, Alveolar / drug effects*
  • Macrophages, Alveolar / metabolism
  • Microspheres*
  • Phagocytosis / drug effects*
  • Phagocytosis / physiology
  • Polyglycolic Acid / administration & dosage*
  • Polyglycolic Acid / pharmacokinetics
  • Polylactic Acid-Polyglycolic Acid Copolymer
  • Polymers / administration & dosage*
  • Polymers / pharmacokinetics
  • Rats
  • Rifampin / administration & dosage*
  • Rifampin / pharmacokinetics

Substances

  • Drug Carriers
  • Polymers
  • Polylactic Acid-Polyglycolic Acid Copolymer
  • Polyglycolic Acid
  • Lactic Acid
  • Rifampin