Evaluation of 99Tcm-labelled human immunoglobulin in animal models of experimentally induced inflammatory lesions.
Human immunoglobulin (HIG) was labelled with 99Tcm using different Sn-ligand (methylene diphosphonate, MDP) in high yields. The effect of Sn:ligand ratios and protein (HIG) on the biodistribution pattern of 99Tcm-HIG in an animal model of turpentine-induced inflammatory lesions was studied. 99Tcm-HIG was excreted predominantly via the renal pathway. The use of higher amounts of MDP and HIG resulted in relatively slower blood clearance and increased uptake of 99Tcm-HIG in various organs. Also, higher amounts of ligand [Sn:MDP (1:5)] resulted in significantly greater bone uptake (P < 0.001), while protein caused slower blood clearance and greater liver uptake. Despite the increased uptake of tracer in various organs, the ratio of inflamed:normal muscle uptake did not change significantly. A scintigraphic study was carried out with both 99Tcm-HIG and 99Tcm labelled with human serum albumin (HSA) in turpentine-induced inflammatory lesions produced in rabbits. The study revealed no significant differences in uptake early on, but the target:non-target ratio was higher with 99Tcm-HIG at 24 h. 99Tcm-HIG also had superior characteristics compared with 99Tcm-HSA.
Shimpi
H H
HH
Radiation Medicine Centre, Bhabha Atomic Research Centre, Tata Memorial Hospital Annex, Parel, Bombay, India.
Noronha
O P
OP
Samuel
A M
AM
D000818:Animals; D001842:Bone and Bones / Q000000981:diagnostic imaging; D006614:Hindlimb; D006801:Humans; D018796:Immunoconjugates / Q000493:pharmacokinetics; D007074:Immunoglobulin G; D016756:Immunoglobulins, Intravenous / Q000493:pharmacokinetics; D007249:Inflammation / Q000139:chemically induced / Q000000981:diagnostic imaging*; D018482:Muscle, Skeletal / Q000000981:diagnostic imaging; D011817:Rabbits; D016719:Radioimmunodetection; D051381:Rats; D017208:Rats, Wistar; D013668:Technetium Tc 99m Aggregated Albumin / Q000493:pharmacokinetics; D013669:Technetium Tc 99m Medronate / Q000493:pharmacokinetics; D014018:Tissue Distribution; D014425:Turpentine / Q000633:toxicity
D018796:Immunoconjugates; D007074:Immunoglobulin G; D016756:Immunoglobulins, Intravenous; D013668:Technetium Tc 99m Aggregated Albumin; C023568:technetium Tc 99m (Sn)methylenediphosphonate; D013669:Technetium Tc 99m Medronate; D014425:Turpentine