ANALYTICAL PERFORMANCES OF COMMERCIAL ELISA-KITS FOR IL-2, IL-6 AND TNF-ALPHA - A WHO STUDY

The determination of cytokine levels in biological fluids by accurate and sensitive methods is an absolute need to be able to define the inv olvement of these mediators in various clinical situations. To test if this goal was achieved with ELISA kits, a comparative study was under taken using various commercial kits (6 for IL-2, 8 for IL-6 and 9 for TNF-alpha). The major aims of the work were to critically analyze the analytical performances of the kits and to illustrate some of the pitf alls the users may face. Substantial differences were noted in terms o f sensitivity and behaviour of commercial standards versus internation al reference preparations. These results clearly illustrate the urgent need for a real standardization of immunoassays for cytokine quantita tion.