Anti-Tocilizumab (ACTEMRA) ELISA Assay Kit
The Anti-Tocilizumab (ACTEMRA) ELISA Assay Kit is For Research Use Only
Size: 12×8 wells
Sensitivity: +/-
Incubation Time: 2 hours 20 minutes
Sample Type: Serum, Plasma
Sample Size: 20 µL
Alternate Name: Actemra
Assay Background
Tocilizumab is a recombinant, humanized, anti-human interleukin 6 (IL-6) receptor monoclonal antibody that achieves a significant therapeutic response rate. The light chain is made up of 214 amino acids. The heavy chain is made up of 448 amino acids. The four polypeptide chains are linked intra- and inter- molecularly by disulfide bonds. FDA approved on January 8, 2010. Tocilizumab (injection) was further approved by the FDA for the treatment of adults with giant cell arteritis, an inflammation of the blood vessels (vasculitis) in May, 2017. In a double-blind, placebo-controlled study, the patients achieved sustained remission from Week 12 through Week 52, which was associated with significant improvements in symptoms of giant cell arteritis, normalization of inflammatory laboratory tests and tapering the use of corticosteroids. Interleukin (IL)-6 plays essential roles not only in the immune response, but also in haematopoiesis and the central nervous system. Unregulated production of IL-6 has been found in chronic inflammatory autoimmune diseases, such as rheumatoid arthritis (RA), systemic onset juvenile idiopathic arthritis (soJIA), Crohn’s disease (CD), systemic lupus erythematosus (SLE) and vasculitis. Furthermore, IL-6 activities can explain many symptoms of these diseases. More importantly, serum levels of IL-6 are correlated with disease activity. Tocilizumab binds specifically to both soluble and membrane-bound IL-6 receptors (sll-6R and mll-6R), and has been shown to inhibit IL-6-mediated signaling through these receptors.
Assay Principle
Solid phase enzyme-linked immunosorbent assay (ELISA) based on the sandwich principle. Controls and samples (serum or plasma) are incubated in the microtiter plate coated with the drug tocilizumab. After incubation, the wells are washed. Then, horse radish peroxidase (HRP) conjugated probe is added and binds to tocilizumab antibodies captured by the drug tocilizumab on the surface of the wells. Following incubation wells are washed and the bound enzymatic activity is detected by addition of chromogen-substrate. Finally, the reaction is terminated with an acidic stop solution. The color developed is proportional to the amount of tocilizumab antibodies in the sample or controls. The results can be evaluated with using cut-off value.
