Description

The Isg15 Knockout HT22 Cell Line is a CRISPR/Cas9-edited knockout cell line targeting the Isg15 gene in Mus musculus. Derived from the HT22 mouse hippocampal neuronal cell line, this product provides a loss-of-function model for investigating ISG15-dependent mechanisms. Gene disruption is achieved via CRISPR/Cas9-mediated editing, eliminating functional ISG15 expression. This model constitutes a reliable tool for studying antiviral immunity, interferon signaling, and neuroinflammation.

The HT22 cell line is an immortalized mouse hippocampal neuronal cell line (subclone of HT4) that recapitulates hippocampal neuron characteristics. It provides a physiologically relevant platform for investigating CNS innate immunity, where ISG15 participates in antiviral defense and neuroinflammatory processes. HT22 cells are amenable to diverse molecular and cellular assays, facilitating dissection of neuron-intrinsic ISGylation and secreted ISG15 functions.

ISG15 is a ubiquitin-like protein robustly induced by type I interferons (IFN-??/??) through the JAK-STAT pathway: IFNAR1/IFNAR2 engagement activates JAK1 and TYK2, which phosphorylate STAT1 and STAT2; these form the ISGF3 complex with IRF9 to transactivate ISRE elements. Upstream stimuli also include IRF3, IRF7, LPS, and viral infection. ISG15 undergoes conjugation (ISGylation) to target proteins via UBA7 (E1), UBE2L6 (E2), and E3 ligases HERC5 and TRIM25; deconjugation is mediated by USP18. ISGylation modifies substrates like IRF3, STAT1, PKR, and viral proteins, impacting NF-??B and JAK-STAT signaling. Additionally, secreted ISG15 acts as a cytokine through LFA-1 integrin to promote IFN-?? production and modulate immune responses.

In the HT22 background, ISG15 knockout enables analysis of neuron-specific ISGylation and cytokine activities. Neurons activate interferon-driven antiviral programs; the contribution of ISG15 to these CNS responses is not fully understood. This model allows exploration of viral susceptibility, interferon-stimulated gene expression, and neuroimmune interactions in the absence of ISG15, while also offering insights into ISG15-linked neuroinflammatory and neurodegenerative conditions.

Typical applications encompass Western blot analysis for ISG15 and global ISGylation, RT-qPCR for Isg15 and ISGs, interferon stimulation and viral infection assays, co-immunoprecipitation of ISGylated substrates, flow cytometry, apoptosis detection, and glutamate toxicity testing. These methods support studies of neuronal innate immunity, ISGylation-dependent signaling in hippocampal neurons, and the immunomodulatory consequences of secreted ISG15. Researchers seeking to examine ISG15 deficiency in a CNS-relevant model will find this knockout cell line highly advantageous. For technical inquiries or further information, please contact Ascent Research.