title: Biodistribution of indium-111-labeled antibody directed against intercellular adhesion molecule-1.
abstract: We examined the biodistribution in normal rats of an 111In-labeled mouse monoclonal antibody to rat intercellular adhesion molecule-1 (111In-alCAM-1), as a potential detector of inflammation.
  
  
  METHODS
  Indium-111-alCAM-1 or 111In-labeled normal mouse polyclonal immunoglobulin G (111In-nmIgG) was injected into rats. Groups of three to four rats were killed up to 18 hr after injection, and activity was measured in various tissues. Rats were also imaged at 1 and 18 hr after injection.
  
  
  RESULTS
  Uptake of 111In-alCAM-1 was greatest in the lung (approximately 10% injected dose [ID]/g at 15 min) and then declined steadily (to approximately 2% ID/g at 18 hr). Lung uptake of 111In-nmIgG was eightfold less than that for 111In-alCAM-1 and did not change throughout the 18 hr. At all time points, blood activity for 111In-alCAM-1 was only 30% to 40% of that for 111In-nmIgG, whereas the percent injected dose per gram was increased more than twofold in the major organs. Compared with 111In-nmIgG, the 111In of alCAM-1 was shifted from the blood and was distributed among the lung kidney, spleen and liver.
  
  
  CONCLUSIONS
  Indium-111-alCAM-1 may be useful as an early inflammation detection agent. Intercellular adhesion molecule-1 upregulation is a very early event in inflammation and rapid removal from the blood of this antibody provides low background in contrast to the usual high background with whole antibodies.
authors.affiliation: Department of Nuclear Medicine, University of Connecticut Health Center, Farmington 06030, USA.
authors.forename: D E
authors.initials: DE
authors.lastname: Sasso
authors.forename: M A
authors.initials: MA
authors.lastname: Gionfriddo
authors.forename: R S
authors.initials: RS
authors.lastname: Thrall
authors.forename: S I
authors.initials: SI
authors.lastname: Syrbu
authors.forename: H M
authors.initials: HM
authors.lastname: Smilowitz
authors.forename: R E
authors.initials: RE
authors.lastname: Weiner
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G; D007205:Indium Radioisotopes; D018799:Intercellular Adhesion Molecule-1 / Q000276:immunology*; D008168:Lung / Q000000981:diagnostic imaging; D008297:Male; D051379:Mice; D016719:Radioimmunodetection; D051381:Rats; D011916:Rats, Inbred F344; D013997:Time Factors; D014018:Tissue Distribution
chemical_list: D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G; D007205:Indium Radioisotopes; D018799:Intercellular Adhesion Molecule-1