Anti-VISA MAVS Antibody

Two distinct signaling pathways activate the host innate immunity against viral infection. One pathway is reliant on members of the Toll-like receptor (TLR) family while the other uses the RNA helicase RIG-I as a receptor for intracellular viral double-stranded RNA as a trigger for the immune response. VISA is a mitochondrial membrane protein that was identified as a critical component in the IFN-b signaling pathways that recruits IRF-3 to RIG-I, leading to its activation and that of NF-κB. VISA is also thought to interact with other components of the innate immune pathway such as the TLR adapter protein TRIF, TRAF2 and TRAF6. VISA also interacts with the IKKα , IKKβ and IKKε kinases through its C-terminal region. Cleavage of this region by the Hepatitis C virus (HCV) protease allows HCV to escape the host immune system. At least three isoforms of VISA are known to exist.

VISA antibody was raised against a 13 amino acid synthetic peptide from near the amino terminus of human VISA. The immunogen is located within the first 50 amino acids of VISA.

Present in T-cells, monocytes, epithelial cells and hepatocytes (at protein level) . Ubiquitously expressed, with highest levels in heart, skeletal muscle, liver, placenta and peripheral blood leukocytes.

Required for innate immune defense against viruses. Acts downstream of DHX33, DDX58/RIG-I and IFIH1/MDA5, which detect intracellular dsRNA produced during viral replication, to coordinate pathways leading to the activation of NF-kappa-B, IRF3 and IRF7, and to the subsequent induction of antiviral cytokines such as IFN-beta and RANTES (CCL5) . Peroxisomal and mitochondrial MAVS act sequentially to create an antiviral cellular state. Upon viral infection, peroxisomal MAVS induces the rapid interferon- independent expression of defense factors that provide short-term protection, whereas mitochondrial MAVS activates an interferon- dependent signaling pathway with delayed kinetics, which amplifies and stabilizes the antiviral response. May activate the same pathways following detection of extracellular dsRNA by TLR3. May protect cells from apoptosis.

VISA antibody can be stored at 4°C for three months and -20°C, stable for up to one year. Avoid repeated freeze-thaw cycles. Antibodies should not be exposed to prolonged high temperatures.