B6-hIL6/IL6RA Mouse

Interleukin-6 (IL-6) is a cytokine that plays a crucial role in inflammation and B cell maturation. It is primarily produced and secreted into the serum at sites of acute and chronic inflammation, inducing inflammatory responses through the interleukin-6 receptor alpha (IL-6Rα). The IL6RA (IL6R, also known as CD126) gene encodes a subunit of the interleukin-6 (IL-6) receptor complex. The IL-6 receptor is a protein complex composed of the IL6RA protein and the interleukin-6 signal transducer (IL6ST/GP130/IL6-beta). This receptor subunit is shared by many other cytokines. The expression of IL-6R is primarily restricted to hepatocytes, leukocytes, and megakaryocytes. Upon binding to IL-6Rα, IL-6 interacts with two GP130 molecules to form a hexameric complex in a 2:2:2 configuration ^[1]. Once the IL-6 receptor complex is activated, multiple downstream events allow IL-6 to mediate its diverse effects. These include the pathways of the GTPase Ras and its effector Raf, the mitogen-activated protein kinase cascade that controls cellular proliferation and differentiation, and the pathways involving tyrosine kinases of the Jak family and transcription factors of the STAT family ^[2]. IL-6 has a broad impact on both immune and non-immune cells. In CD4+ T helper (Th) cells, IL-6 drives the differentiation of activated naïve Th cells into IL-17 and IL-22 expressing Th17 and Th22 cells, which are crucial for anti-bacterial and anti-fungal defense. Conversely, IL-6 inhibits the differentiation of CD4+ T regulatory cells, which play a key role in restraining inflammatory responses. In hepatocytes, IL-6 induces the expression of inflammation-induced acute phase proteins, including C-reactive protein (CRP) ^[1]. Research has shown that the IL-6 pathway is crucial for maintaining homeostasis and is involved in the dysregulation seen in many diseases. Antibody drugs targeting the IL-6/IL-6 receptor signaling pathway have become innovative therapies for autoimmune diseases and cancers ^[2-5].

The B6-hIL6/IL6RA mice are a double-gene humanized model obtained by breeding B6-hIL6 mice (Catalog No. C001605) with B6-hIL6RA mice (Catalog No. C001606). This model can be used in researching autoimmune diseases, inflammation-related diseases, cancer, and infectious diseases. It is also useful for the development, screening, and evaluation of IL6/IL6RA-targeted drugs.