Inhibitory Action of Cytokine Preservatives on Chemiluminescence Assays

Abstract

Commercial tumor necrosis factor alpha (TNFα) reportedly stimulates hydrogen peroxide-mediated chemiluminescence in macrophages. However, two commercially available forms of TNFα, a sodium azide-containing recombinant human TNFα and an azide-free murine TNFα, had opposite effects on a cell-free hydrogen peroxide chemiluminescence assay. Azide-free murine TNFα stimulated peroxide-associated chemiluminescence, while the azide-containing human TNFα strongly inhibited chemiluminescence. The inhibition of hydrogen peroxide chemiluminescence by the azide-containing TNFα was attributable to small quantities of sodium azide and bovine serum albumin used as preservatives and carriers, respectively.

Key Words: :

• azides
• bovine serum albumin
• chemiluminescence
• oxygen radicals
• preservatives
• TNFα