The Quantikine Human CTACK Immunoassay is a 4.5 hour solid-phase ELISA designed to measure human CTACK in cell culture supernates, serum, and plasma. It contains E. coli-expressed recombinant human CTACK and has been shown to accurately quantitate the recombinant factor. Results obtained using natural human CTACK showed linear curves that were parallel to the standard curves obtained using the Quantikine kit standards. These results indicate that this kit can be used to determine relative mass values for naturally occurring CTACK. Range: 15.60 - 1000 pg/mL. Sensitivity: 4.68 pg/mL. Time: 4.5 hours