Anti-Human IL-6R (CD126) (Satralizumab) (I-1270-25mg)

IL-6 is a pleiotropic cytokine that promotes B cell and T cell proliferation and differentiation and is also involved in the inflammatory response1. In the ‘classic’ signaling paradigm, IL-6 binds to its membrane bound receptor IL-6R to initiate intracellular signaling pathways2. Alternatively, in ‘trans-signaling’, IL-6 binds to a soluble form of IL-6R. In both events, a complex set of interactions with membrane-bound or soluble β-receptor glycoprotein 130 (gp130) modulates the downstream signaling pathways. Additionally, IL-6 plays an inflammatory role in autoimmune diseases3 and high IL-6 levels are a feature of cytokine storm and cytokine release syndrome during COVID-19 infection1. IL-6 signaling can be inhibited by antibodies directed against IL- 6R3. SA237 (Satralizumab) is a humanized monoclonal recycling antibody that was developed for the treatment of neuromyelitis optica spectrum disorder, a rare autoimmune disease of the central nervous system4. Satralizumab binds to both membrane and soluble IL-6R, thereby inhibiting IL-6 signaling as well as reducing inflammation and IL-6 mediated autoimmune T cell and B cell activation. Ultimately, B cell differentiation into AQP4-IgG-secreting plasmablasts is prevented. Satralizumab circulation in the body is extended via a novel recycling technology that allows for pH dependent dissociation from IL-6R in the endosome after cellular uptake. Satralizumab is then transported back to the plasma membrane via the recycling endosomal pathway and released into plasma for reuse. Satralizumab is produced in Chinese hamster ovary cells using recombinant DNA technology4. Satralizumab does not cross react with rodent IL-6R5.