CASP4 Knockout SK-HEP-1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population targeting the CASP4 gene in human SK-HEP-1 liver adenocarcinoma cells. This polyclonal pool contains diverse loss-of-function edits, eliminating functional CASP4 to enable studies of non-canonical inflammasome signaling and pyroptosis. The model circumvents clonal selection, maintaining genetic heterogeneity relevant for population-level analyses in innate immunity research.
The SK-HEP-1 cell line, derived from ascites of a patient with liver adenocarcinoma, exhibits endothelial-like characteristics and serves as a model for liver sinusoidal endothelial cells. It is widely used in liver cancer biology, drug metabolism, and hepatic innate immune studies. SK-HEP-1 cells express the necessary machinery for LPS sensing and inflammasome activation, providing a physiologically relevant context for dissecting CASP4 function in the liver microenvironment.
CASP4 is an intracellular receptor that binds LPS via its CARD domain, leading to oligomerization, activation, and cleavage of gasdermin D (GSDMD). GSDMD N-terminal fragments form membrane pores, executing pyroptosis and releasing IL-1?? and IL-18. CASP4 activity is regulated by TLR4 signaling, interferon-gamma, and NF-??B, and it engages downstream caspase-1. It also interacts with NLRP3 inflammasome components, amplifies NLRP3/ASC-mediated signaling, and associates with RIPK1, linking inflammatory cell death to ER stress-induced apoptosis.
In SK-HEP-1 endothelial-like cells, CASP4 knockout disrupts LPS-induced pyroptosis, providing a clean system to study hepatic innate immunity. This model allows investigation of how liver sinusoidal endothelial cells respond to bacterial products and stress, contributing to sepsis-associated liver injury without interference from myeloid-specific pathways. The polyclonal format captures a range of knockout efficiencies, facilitating robust assessment of CASP4-dependent phenotypes at the population level.
Applications include LPS transfection assays to activate non-canonical inflammasomes, LDH release and western blotting for GSDMD cleavage to assess pyroptosis, and ELISA for IL-1??/IL-18 quantification. Flow cytometry enables cell death analysis, while co-immunoprecipitation reveals CASP4 interactions with NLRP3 or RIPK1. This knockout model supports drug screening for inflammatory diseases, host-pathogen interaction studies, and inflammasome biology research. For more information, please contact Ascent Research.
