Invitrogen™ ISG15 Monoclonal Antibody (3C2), eBioscience™, Invitrogen™

Description

Description: This 3C2 monoclonal antibody reacts with mouse interferon stimulated gene-15 (ISG-15), a 15kDa ubiquitin-like protein (UBL) and cytokine. ISG-15 is translated as a precursor that is subsequently activated by an E1 enzyme, conjugated by an E2 enzyme via the C-terminal LRLRGG motif and ligated by an E3 ligase. The activity of ISG-15 is dependent on its modification of target proteins at specific lysine residues. Several viruses utilize ISG-15 and ubiquitin deconjugating proteases, while influenza B protein NS1 has been shown to specifically bind ISG-15 thereby blocking its conjugation. In addition to its role as a protein modification, ISG-15 is secreted by monocytes and lymphocytes in response to IFNalpha, beta, or gamma, as well as influenza B virus. In this role as cytokine, it has been shown to induce secretion of IFNgamma and support NK cell proliferation and cytolytic activity. Applications Reported: This 3C2 antibody has been reported for use in immunoblotting (WB). Applications Tested: This 3C2 antibody has been tested by immunoblot of Raw 264.7 cell lysates at 2 μg/mL. It is recommended that the antibody be carefully titrated for optimal performance in the assay of interest. Purity: Greater than 90%, as determined by SDS-PAGE. Aggregation: Less than 10%, as determined by HPLC. Filtration: 0.2 μm post-manufacturing filtered.

Ubiquitin-like protein ISG15 plays a key role in the innate immune response to viral infection either via its conjugation to a target protein (ISGylation) or via its action as a free or unconjugated protein. It is secreted from monocytes in response to type I interferons and causes natural killer (NK)-cell proliferation and an augmentation of non-MCH (major histocompatibility complex)-restricted cytotoxicity. Synthesis is stimulated by IFN-alpha or IFN-beta or IFN-omega, but not IFN-gamma. ISG15 expression is also induced by overexpression of interferon regulatory factors that participate in transcriptional regulation of IFN genes, and by influenza B virus. ISG15 is secreted by cell lines of monocyte, T-lymphocyte, B-lymphocyte, human fibroblasts, and epithelial origins. Enhancement of NK cell proliferation, augmentation of non-major histocompatibility complex-restricted cytotoxicity, and induction of IFN-gamma from T cells identify ISG15 as a member of the cytokine cascade and suggest that it may be responsible for amplifying and directing some of the immunomodulatory effects of IFN-alpha or IFN-beta. ISG15 has has also been shown to function intracellularly as a ubiquitin homolog. Mutations affecting the gene can result in Immunodeficiency 38, with basal ganglia calcification (IMD38).