The CASP8 Knockout HeLa Polyclonal Cells consist of a CRISPR/Cas9-edited HeLa cell pool with targeted disruption of the CASP8 gene, generating a heterogeneous population of knockout variants. This polyclonal format eliminates single-cell cloning artifacts and is well-suited for functional genomics studies, high-throughput screening, and pathway analysis requiring representative cell mixtures.
HeLa cells are a widely used human cervical adenocarcinoma line positive for integrated HPV18 sequences. The viral E6 and E7 oncoproteins inactivate p53 and Rb, respectively, disrupting cell cycle control and DNA damage responses. This results in a hyperproliferative phenotype with inherent apoptosis resistance, making HeLa an informative host for studying defects in extrinsic cell death signaling often seen in cancers.
CASP8 encodes caspase-8, an initiator protease of the extrinsic apoptosis pathway. Upon death receptor ligation (e.g., FAS, TNFR1, TRAILR1/2 by FASL, TNF-??, TRAIL), caspase-8 is recruited to DISC via FADD, where c-FLIP regulates its activation. Activated caspase-8 cleaves effector caspases-3, -6, -7 and BID, connecting extrinsic signals to mitochondrial apoptosis. Additionally, caspase-8 suppresses necroptosis by cleaving RIPK1 and modulates NF-??B and autophagy pathways through TRAF2 interactions, positioning it at a critical node between cell death and inflammatory signaling.
Within the HeLa context, loss of p53 and Rb function already tilts the balance away from apoptosis; ablating CASP8 further disables extrinsic death receptor pathways and may promote necroptotic or inflammatory phenotypes. This polyclonal knockout model therefore enables dissection of how caspase-8 deficiency reshapes death ligand responses and drug sensitivity in cervical cancer, revealing mechanisms of apoptosis evasion and identifying potential targets for therapeutic intervention.
Applications include Annexin V/PI apoptosis assays following FASL or TNF-?? stimulation, cell viability measurements under drug treatment, and caspase activity profiling with fluorogenic substrates. Western blotting for caspase-8 and cleavage products (caspase-3, BID) confirms knockout effects, while co-immunoprecipitation with DISC constituents (FADD, c-FLIP) probes complex formation. RT-qPCR analyses of downstream genes and necroptosis markers (e.g., RIPK1) can map pathway crosstalk. This model supports research in cancer, ALPS, inflammatory diseases, and neurodegeneration. For further technical support, please contact Ascent Research.
