title: Targeting microparticles to select tissue via radiation-induced upregulation of endothelial cell adhesion molecules.
abstract: OBJECTIVE
  Certain endothelial cell adhesion molecules are up regulated in tissue that has been irradiated for therapeutic purposes. This up-regulation of adhesion molecules provides a potential avenue for targeting drugs to select tissues.
  
  
  METHODS
  Microspheres were coated with a mAb to ICAM-1 and the level of adhesion of the anti-ICAM-1 microspheres to irradiated tissue in vitro and in vivo was quantified.
  
  
  RESULTS
  Under in vitro flow conditions, the number of adherent microspheres on irradiated HUVEC was 4.8 +/- 0.9 times that of control; the adhesion of anti-ICAM-1 microspheres on irradiated HUVEC could be enhanced by more than 170% in the presence of RBC (20% hematocrit) in the medium. In vivo in a rat cranial window model, the number of adherent anti-ICAM-1 microspheres in locally irradiated cerebral tissue was 8 and 13 times that of IgG microspheres at 24 h and 48 h post-irradiation, respectively and returned to baseline 7 days post-irradiation. In locally irradiated animals, the number of adhering microspheres in unirradiated tissue remained at the basal level.
  
  
  CONCLUSIONS
  Radiation-induced up-regulation of endothelial cell adhesion molecules may be exploited to target drugs and/or genes to select segments of the endothelium.
authors.affiliation: School of Biomedical Engineering, Department of Radiation Oncology, University of Tennessee Health Science Center, Memphis 38163, USA. mkiani@utmem.edu
authors.forename: Mohammad F
authors.initials: MF
authors.lastname: Kiani
authors.forename: Hong
authors.initials: H
authors.lastname: Yuan
authors.forename: Xin
authors.initials: X
authors.lastname: Chen
authors.forename: Lee
authors.initials: L
authors.lastname: Smith
authors.forename: M Waleed
authors.initials: MW
authors.lastname: Gaber
authors.forename: Douglas J
authors.initials: DJ
authors.lastname: Goetz
mesh_terms: D000818:Animals; D015815:Cell Adhesion Molecules / Q000528:radiation effects*; D016503:Drug Delivery Systems / Q000379:methods*; D004730:Endothelium, Vascular / Q000187:drug effects / Q000528:radiation effects*; D006801:Humans; D008863:Microspheres; D051381:Rats; D015854:Up-Regulation / Q000187:drug effects / Q000528:radiation effects*
chemical_list: D015815:Cell Adhesion Molecules