title: The effect of 'irrelevant' IgG protein selection on target uptake ratios of radiolabeled antibodies.
abstract: The uptake ratios of radiolabeled antibodies (Ab) commonly are two to three times the uptake ratios of the normal surrounding tissue. In an experimental crush injury model, we also defined a two to three times greater range of uptake of type I anticollagen antibody (Ac-Ab-I) from 1.5 hours to 48 hours after tail injury in the rat. Specific target uptake, however, often is further categorized by comparing the uptake ratio of Ab to that of a nonspecific protein. We present data to indicate that this nonspecific uptake may represent a significant variable. We found that sheep IgG gave consistently less nonspecific uptake in our model than did rabbit IgG. In the acute model (protein injected 1.5 hours after injury), damaged: normal tail ratios were Ac-Ab-I = 2.34, sheep = 0.8, and rabbit = 1.6. The extent of specific Ab uptake seems dependent upon the choice of "irrelevant" IgG controls.
authors.affiliation: Bowman Gray School of Medicine, Department of Radiology, Winston-Salem, North Carolina.
authors.forename: R
authors.initials: R
authors.lastname: Freimanis
authors.forename: S S
authors.initials: SS
authors.lastname: Zoghbi
authors.forename: A
authors.initials: A
authors.lastname: Gottschalk
mesh_terms: D000818:Animals; D000906:Antibodies / Q000276:immunology*; D003094:Collagen / Q000276:immunology*; D004912:Erythrocytes; D007074:Immunoglobulin G / Q000276:immunology*; D007205:Indium Radioisotopes; D011877:Radionuclide Imaging; D051381:Rats; D011971:Receptors, Immunologic / Q000276:immunology*; D013623:Tail / Q000000981:diagnostic imaging / Q000293:injuries; D013667:Technetium
chemical_list: D000906:Antibodies; D007074:Immunoglobulin G; D007205:Indium Radioisotopes; D011971:Receptors, Immunologic; D013667:Technetium; D003094:Collagen