The CASP8 Knockout A-549 Polyclonal Cells product provides a CRISPR/Cas9-edited polyclonal knockout population of A-549 human lung adenocarcinoma cells, featuring targeted disruption of CASP8. This heterogeneous pool serves as a loss-of-function model for caspase-8, the initiator caspase of extrinsic apoptosis, enabling pooled functional studies and phenotypic screening without clonal biases.
A-549 cells are an adherent epithelial line isolated from the lung adenocarcinoma of a 58-year-old Caucasian male, widely used as a model for non-small cell lung cancer and respiratory epithelium. Their well-characterized apoptotic and inflammatory signaling make them suitable for dissecting cell death pathway alterations in a disease-relevant context.
CASP8 encodes caspase-8, which is activated by death receptors (FAS, TNFR1, TNFRSF10A/B) upon binding of ligands such as FASLG, TNF, and TRAIL. FADD-mediated DISC assembly recruits procaspase-8, leading to autoproteolytic activation that cleaves executioner caspases CASP3 and CASP7 and the BH3-only protein BID to induce apoptosis. Caspase-8 also interacts with CFLAR, RIPK1, and adaptors TRADD and TRAF2, regulating necroptosis and NF-??B signaling. When caspase-8 is inhibited, RIPK1 engages RIPK3 and MLKL to execute necroptosis. Additionally, caspase-8 modulates inflammasome function through cleavage of gasdermin proteins GSDMC and GSDMD. Disruption of CASP8 thus abolishes extrinsic apoptosis, promoting necroptosis or altering inflammatory responses.
In A-549 lung adenocarcinoma cells, CASP8 knockout can shift death receptor signaling toward necroptosis or confer apoptosis resistance, mirroring mechanisms of drug resistance in non-small cell lung cancer. This model enables investigation of tumor cell survival and sensitivity to therapies like TRAIL receptor agonists, providing a platform to study adaptive signaling rewiring and immune evasion.
Key applications include Western blotting for caspase-8, cleaved caspase-3, and PARP; flow cytometry (Annexin V/PI) for apoptosis quantification; cell viability (MTT/XTT) assays; phospho-MLKL immunodetection for necroptosis; and co-immunoprecipitation of DISC components (e.g., FADD). This tool supports extrinsic apoptosis pathway analysis, necroptosis mechanism studies, drug resistance profiling, death receptor agonist testing, and inflammasome regulation research. For additional details, contact Ascent Research.
