Preparation of protein loaded poly(D,L-lactide-co-glycolide) microparticles for the antigen delivery to dendritic cells using a static micromixer

Eur J Pharm Biopharm. 2006 Apr;62(3):247-53. doi: 10.1016/j.ejpb.2005.08.015. Epub 2005 Nov 8.


The cellular immune response against tumors, viruses, or intracellular bacteria requires adequate antigen delivery to professional phagocytes, their processing and the presentation of antigenic peptides to T-cells. Biodegradable microparticles to enhance antigen phagocytosis and the response of cytotoxic lymphocytes have been proposed. The aim of the present study was to formulate poly(lactide-co-glycolide) (PLGA) microparticles using a w/o/w solvent evaporation procedure in order to obtain suitable vehicles for vaccination. Bovine serum albumin bearing fluorescein isothiocyanate (FITC-BSA) was used as a model antigen. For microparticle preparation a static micromixer was employed. Microparticles of 2-3 microm can be produced with good reproducibility by applying high flow rates at the micromixer. Microparticles with a smooth surface and only one pore were observed using scanning electron microscopy (SEM). Confocal laser scanning microscopy (CLSM) allowed localisation of the FITC-BSA near the surface of the microparticle. Microencapsulation of FITC-BSA did not altered the polymer characteristics, as determined by measuring the glass transition temperature. Additionally we could determine residual methylene chloride, employed as solvent in microparticle preparation, to be less than 1/1000 of the USP and Ph. Eur. limit. The microparticles described herein were able to deliver the model antigen to human dendritic cells (DC).

MeSH terms

  • Antigen-Presenting Cells
  • Antigens / administration & dosage*
  • Calorimetry, Differential Scanning
  • Chemistry, Pharmaceutical
  • Chromatography, High Pressure Liquid
  • Dendritic Cells / drug effects*
  • Drug Compounding / instrumentation*
  • Drug Compounding / methods*
  • Drug Delivery Systems*
  • Fluorescein-5-isothiocyanate
  • Fluorescent Dyes
  • Granulocyte-Macrophage Colony-Stimulating Factor / metabolism
  • Humans
  • Interleukin-4 / metabolism
  • Lactic Acid / chemical synthesis*
  • Lactic Acid / pharmacology*
  • Microscopy, Electron, Scanning
  • Nanostructures
  • Particle Size
  • Polyglycolic Acid / chemical synthesis*
  • Polyglycolic Acid / pharmacology*
  • Polylactic Acid-Polyglycolic Acid Copolymer
  • Polymers / chemical synthesis*
  • Polymers / pharmacology*
  • Serum Albumin, Bovine
  • Solvents


  • Antigens
  • Fluorescent Dyes
  • Polymers
  • Solvents
  • Polylactic Acid-Polyglycolic Acid Copolymer
  • Interleukin-4
  • Polyglycolic Acid
  • Serum Albumin, Bovine
  • Lactic Acid
  • Granulocyte-Macrophage Colony-Stimulating Factor
  • Fluorescein-5-isothiocyanate