F-18 LABELED CHEMOTACTIC PEPTIDES - A POTENTIAL APPROACH FOR THE PET IMAGING OF BACTERIAL-INFECTION

A potent chemotactic peptide, formyl-norleucyl-leucyl-phenylalanyl-norleucyl-tyrosyl-lysine was derivatized by reaction with N-succinimidyl f-fluorobenzoate. This derivatized peptide bound to human polymorphonuclear leukocytes in vitro and exhibited biological activity in a superoxide production assay. Peptide labeling using N-succinimidyl 4-[F-18]fluorobenzoate was accomplished in reasonable yields with 10-15 mCi of labeled peptide available per 100 Ci of [F-18]fluoride. With the exception of the gastrointestinal tract, clearance of activity from tissues following injection of this peptide in normal mice was rapid. Although preliminary in nature, these results suggest that F-18-labeled chemotactic peptides should be investigated as potential agents for positron emission tomographic imaging of bacterial infections.