Technetium-99m-white blood cell-specific imaging agent developed from platelet factor 4 to detect infection.

摘要: We have developed a leukocyte-avid, 99m Tc-labeled peptide (P483H) as potential imaging agent for infection. P483H contains the heparin-binding region of platelet factor-4 (PF-4) and lysine-rich sequence rapid renal clearance. Technetium-99m-P483H was evaluated its ability to selectively label white blood cells (WBCs) in vitro detect focal E. coli infections rabbits. Methods : incubated with citrated whole human blood, layered onto WBC isolation media subjected density gradient centrifugation measure WBC-associated radioactivity. Indium-111-WBCs Tc-gluceptate were used controls. In vivo model, infected rabbits imaged necropsied 4 hr after administration Tc-P483H. Infected contralateral control muscles %ID, %ID/g, I max (muscle sample showing highest uptake, i.e., %ID/g) -to-blood -to-control muscle ratios. Indium-111-WBCs, 111 In-DTPA, 131 I-albumin (HSA), Tc-nanocolloid, 67 Ga Results associated predominantly WBCs vitro, Tc-P483H provided high contrast images infection vivo. 73% radioactivity WBCs. outperformed In-WBCs, I-albumin, Ga-citrate an average 0.062 %ID/g (±0.029 ; n = 48). also all controls, including Tc-gluceptate. The ratios averaged 3.1 (±2.4) 26.8 (±16.8), respectively, again Conclusion associates identified within versus conventional agents. Additionally, showed clearance exclusive excretion, which provides clear abdominal field infections.