Interference of soluble TNF-alpha receptors in immunological detection of tumor necrosis factor-alpha.
We have studied the interference of soluble tumor necrosis factor-alpha receptor p55 (sTNF-R55) on the quantification of tumor necrosis factor-alpha (TNF-alpha) in three immunoassays: the commercially available enzyme amplified-sensitivity immunoassay (EASIA) of Medgenix and the ELISA of Boehringer Mannheim, and an assay based on electrochemiluminescence (ECL) technology. TNF-alpha measurements by EASIA and ELISA were not affected by the presence of sTNF-R55, but results by the ECL method were clearly influenced by the receptor. We then performed a second set of experiments with the ECL system to examine what factors might influence the importance of interference from sTNF-R55 and soluble TNF-alpha receptor p75 (sTNF-R75), which influences TNF-alpha measurements the same as sTNF-R55. We found that extending the incubation time and increasing the concentration of capture antibody decreased the interfering capacity of sTNF-R55 and sTNF-R75. A clear insight into these phenomena is of utmost importance for correct interpretation of cytokine quantification.
Moreau
E
E
Department of Clinical Chemistry, Microbiology, and Immunology, University Hospital Gent, Belgium.
Philippé
J
J
Couvent
S
S
Leroux-Roels
G
G
D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D006801:Humans; D007124:Immunoenzyme Techniques; D008163:Luminescent Measurements; D018124:Receptors, Tumor Necrosis Factor / Q000032:analysis / Q000276:immunology*; D012995:Solubility; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis*
D018124:Receptors, Tumor Necrosis Factor; D014409:Tumor Necrosis Factor-alpha