99mTc-Labeled Interleukin 8 for the Scintigraphic Detection of Infection and Inflammation: First Clinical Evaluation

Interleukin 8 (IL-8) is a chemotactic cytokine that binds with a high affinity to receptors expressed on neutrophils. Previous studies with various animal models showed that 99mTc-labeled IL-8 accumulates specifically and rapidly in infectious and in-flammatory foci. The aims of the present study were to evaluate the safety of IL-8 in humans and to assess the value of 99mTc-IL-8 scintigraphy in patients with suspected localized infections. Methods: 99mTc-IL-8 was intravenously injected at 400 MBq into 20 patients with various suspected localized infections. Pa-tients weremonitored for IL-8–related side effects for 4 h.Whole-body imaging was performed directly after injection and at 4 h after injection. Imaging after 24 hwas performed for the first 7 pa-tients and for subsequent patients when the results of 99mTc-IL-8 scintigraphy at 4 h after injectionwere normal or equivocal. Blood was drawn at several time points to determine the total number o