The CASP4 Knockout HAP1 Polyclonal Cells product comprises a CRISPR/Cas9-edited polyclonal knockout cell population designed to disrupt the human CASP4 gene in the HAP1 cell line. This polyclonal knockout cell population is generated through CRISPR/Cas9-mediated gene disruption, creating a heterogeneous pool of edited cells that serve as a loss-of-function model for studying caspase-4-dependent biological processes. Unlike monoclonal cell lines, this polyclonal population captures a range of genetic edits, providing a more representative background for functional assays while maintaining robust gene targeting efficiency. The product is suitable for researchers investigating innate immunity, pyroptosis, and inflammatory signaling without the selection bottlenecks associated with single-cell clones.
The host cell line, HAP1, is a near-haploid human cell line derived from the KBM-7 chronic myeloid leukemia (CML) line. Its near-haploid karyotype, with disomy only for chromosome 8, simplifies genetic manipulation because a single CRISPR/Cas9-induced mutation can lead to functional gene disruption. HAP1 cells exhibit adherent growth and a stable karyotype, making them a reliable platform for reproducible cell-based assays. Their haploid nature reduces genetic redundancy and facilitates straightforward interpretation of knockout phenotypes, which is particularly advantageous for pathway analysis and high-throughput screening applications.
CASP4 encodes an inflammatory caspase that functions as an intracellular sensor for cytosolic lipopolysaccharide (LPS), coupling innate immune detection to pyroptotic cell death. Upon binding LPS, CASP4 undergoes oligomerization and directly cleaves gasdermin D (GSDMD), releasing its N-terminal pore-forming domain to execute pyroptosis and promote release of IL-1?? and IL-18. This activity lies within the non-canonical inflammasome pathway and is regulated by upstream factors including type I interferons and the transcription factors IRF2 and NF-??B. Additionally, CASP4-mediated GSDMD cleavage triggers NLRP3 inflammasome activation, establishing crosstalk with the canonical inflammasome through ASC and caspase-1, thereby amplifying inflammatory responses.
In the HAP1 background, CASP4 knockout provides a genetically simplified system to dissect these signaling networks. The cells endogenously express key inflammasome components such as NLRP3, ASC, and GSDMD, enabling researchers to study caspase-4-dependent pyroptosis and cytokine release without interference from a diploid gene complement. The polyclonal knockout population is particularly useful for investigating population-level responses to LPS stimulation, as it avoids clonal artifacts and reflects a broader spectrum of cellular behaviors. This makes it a powerful tool for mechanistic studies of non-canonical inflammasome biology and for validating the specificity of pharmacological inhibitors.
This knockout product is suited for a variety of experimental workflows in innate immunity and disease research. Researchers can employ Western blotting to confirm CASP4 disruption and monitor GSDMD cleavage, LDH release assays to quantify pyroptotic cell death, and ELISA to measure IL-1?? and IL-18 secretion following cytosolic LPS delivery. The cells are valuable for studying sepsis, inflammatory bowel disease, and neurodegenerative disorders, where non-canonical inflammasome signaling is implicated. Additionally, they support drug screening campaigns targeting the inflammasome, as the haploid background reduces off-target genetic effects. For further information on this product, please contact Ascent Research.
