99Tcm-glutathione for imaging inflammatory lesions.

The purpose of this study was to demonstrate the accumulation of 99Tcm-glutathione (GSH) in experimental abscesses. The biodistribution of 99Tcm-GSH was determined in mice with turpentine-induced abscesses in comparison with 99Tcm-human immunoglobulin (HIG) at 1, 3, 6 and 24 h. Arthritis was induced by intra-articular injection of ovalbumin in the right front knees of 16 rabbits. Each radiopharmaceutical (RP) was administered intravenously to eight rabbits. Scintigrams were obtained and regions of interest (ROIs) over the involved and contralateral knees were compared. Blood clearance of both RPs was studied in 10 normal rabbits. Biodistribution studies indicated accumulation of 99Tcm-GSH in abscesses. Abscess to liver, muscle, intestine and blood ratios were higher at all time points compared to 99Tcm-HIG. The maximum abscess:muscle ratios were 7.57 +/- 0.73 and 5.98 +/- 1.17 at 24 h for 99Tcm-GSH and 99Tcm-HIG, respectively. Scintigraphic images demonstrated both the abscesses and arthritic joints very well. 99Tcm-GSH is superior to 99Tcm-HIG due to clearance predominantly via kidneys, no significant accumulation in any other organs, high target-to-nontarget ratios attained a few hours after administration, low cost and in-house preparation by a simple procedure.