Interleukin-6Rα/CD126 Chimeric Monoclonal Antibody (Clone rhPM-1 (Tocilizumab))

Interleukin-6Rα (IL-6Rα), also known as CD126, is a type I cytokine receptor.¹ It is composed of an immunoglobulin-like domain, a cytokine-binding domain, a transmembrane domain, and a cytoplasmic domain and forms a heteromeric complex with IL-6 and gp130, which is the signal transducing subunit of the IL-6R that primarily acts through the JAK/STAT3 pathway.² IL-6Rα is expressed in hepatocytes and monocytes and is localized to the plasma membrane but also exists as a soluble form (sIL-6Rα) that is primarily generated via proteolytic cleavage of membrane-bound IL-6Rα, but can also be formed via alternative splicing.^3,4,5 Binding of IL-6 to membrane-bound IL-6Rα, known as classical signaling, upregulates the synthesis of acute phase proteins, induces lipolysis in the liver, and induces the differentiation of T and B cells and is primarily anti-inflammatory.^6,7 Trans-signaling consists of IL-6 binding to sIL-6R, which has various pro-inflammatory effects. Knockdown of IL6R increases sensitivity to tamoxifen in breast cancer cells.⁸ Formulations containing chimeric anti-IL-6Rα monoclonal antibodies have been used in the treatment of rheumatoid arthritis, idiopathic arthritis, giant cell arteritis, cytokine release syndrome, and COVID-19. Cayman’s Interleukin-6Rα/CD126 Chimeric Monoclonal Antibody (Clone rhPM-1 (Tocilizumab)) was produced recombinantly from the original rhPM-1 antibody and can be used for ELISA. The rhPM-1 antibody was generated by CDR grafting of mouse PM-1 antibody onto human REI and NEW framework regions.⁹

WARNING This product is not for human or veterinary use.

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