Early detection of oleic acid-induced lung injury in rats using (111)In-labeled anti-rat intercellular adhesion molecule-1.
Previous study of the bleomycin-induced lung injury model suggested that (111)In-labeled antirat intercellular adhesion molecule-1 (aICAM-1) might be a useful acute respiratory distress syndrome (ARDS) diagnostic agent. We further investigated the ability of (111)In-aICAM-1 to detect inflammation in another ARDS lung injury model.


METHODS
(111)In-labeled rat polymorphonuclear leukocytes (PMNs), (111)In-aICAM-1, (111)In-labeled normal mouse IgG (nmIgG), and (111)In-labeled rat serum albumin (RSA) were injected into rats 18-24 h before kill. Biodistributions, scintigraphic images, and lung ICAM-1 upregulation were obtained in uninjured rats and in rats after injury with oleic acid.


RESULTS
(111)In-RSA and (111)In-nmIgG localized in inflamed lung at 5 min postinjury (PI). (111)In-PMN uptake increased significantly only at 24 h PI. (111)In-aICAM-1 localization increased significantly (30%-60%) at 1 h PI and remained elevated up to 24 h PI. Lung/blood ratios (L/B) at 1 and 4 h PI were very low (<0.6) for (111)In-nmIgG and (111)In-PMN rats; however, for (111)In-aICAM-1 rats, they were >1 and 25%-60% higher than those for the control samples. A low L/B suggests poor inflammation detection on the images. Images and region-of-interest analysis confirmed that only (111)In-aICAM-1 could distinguish inflamed lungs at 4 h PI. ICAM-1 was upregulated at 4 and 24 h PI.


CONCLUSIONS
In this model, (111)In-aICAM-1 detected lung inflammation very early in the course of the disease. These results support the suggestion that (111)In-aICAM-1 could be a very early, highly specific ARDS diagnostic agent and may be useful to detect a wide range of inflammations.
Weiner
R E
RE
Department of Diagnostic Imaging and Therapeutics, University of Connecticut Health Center, Farmington, CT 06030, USA.
Sasso
D E
DE
Gionfriddo
M A
MA
Thrall
R S
RS
Syrbu
S
S
Smilowitz
H M
HM
Vento
J
J
D000818:Animals; D000911:Antibodies, Monoclonal / Q000493:pharmacokinetics; D005455:Fluorescent Antibody Technique; D007074:Immunoglobulin G; D007205:Indium Radioisotopes / Q000493:pharmacokinetics; D018799:Intercellular Adhesion Molecule-1 / Q000276:immunology*; D008168:Lung / Q000737:chemistry / Q000000981:diagnostic imaging*; D051379:Mice; D009504:Neutrophils; D019301:Oleic Acid; D011877:Radionuclide Imaging; D051381:Rats; D011916:Rats, Inbred F344; D012128:Respiratory Distress Syndrome / Q000139:chemically induced / Q000000981:diagnostic imaging*; D012709:Serum Albumin; D014018:Tissue Distribution
D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G; D007205:Indium Radioisotopes; D012709:Serum Albumin; D018799:Intercellular Adhesion Molecule-1; D019301:Oleic Acid