ISG15 (Interferon-stimulated gene 15) antibodies are essential tools for studying the ubiquitin-like protein ISG15. a key component of the innate immune response. ISG15 is rapidly induced by type I interferons (IFN-α/β) during viral or bacterial infections, stress, or cancer. It functions through a post-translational modification process called ISGylation, where ISG15 conjugates to target proteins via a cascade involving E1 (UBE1L), E2 (UBCH8), and E3 ligases. This modification regulates diverse cellular processes, including protein stability, immune signaling, antiviral defense, and DNA repair.
ISG15 antibodies are widely used to detect both free ISG15 and ISG15-conjugated proteins in techniques such as Western blotting, immunohistochemistry, and immunofluorescence. They play a critical role in investigating ISG15’s dual roles: as an intracellular modifier modulating host defense pathways and as a secreted cytokine influencing immune cell communication. Researchers also utilize these antibodies to explore ISG15’s involvement in diseases, such as autoimmune disorders (e.g., lupus), viral infections (e.g., influenza, HIV), and cancer, where dysregulated ISGylation is often observed.
Commercial ISG15 antibodies are typically raised against human or mouse ISG15 and validated for species specificity. Their applications extend to studying interferon signaling dynamics, pathogen-host interactions, and therapeutic targets. However, cross-reactivity with ubiquitin or other ubiquitin-like proteins requires careful validation using ISG15-knockout controls.