The CD59 Knockout SK-HEP-1 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout population of human liver adenocarcinoma SK-HEP-1 cells, with targeted disruption of the CD59 complement regulatory gene. This loss-of-function model enables studies of complement regulation and immune evasion without clonal artifacts inherent to single-cell clones. The mixed edited population provides robust and reproducible material for investigating complement-dependent cytotoxicity (CDC) and therapeutic complement activation.
SK-HEP-1 is an epithelial adherent cell line derived from a human liver adenocarcinoma, displaying hepatocellular carcinoma characteristics such as anchorage-independent growth and hepatic marker expression. It is extensively used in cancer biology, drug metabolism, and complement research. The liver origin is advantageous for examining complement-mediated immune surveillance in the hepatic tumor microenvironment, where complement proteins influence tumor progression and therapy response.
CD59 is a GPI-anchored glycoprotein and the primary inhibitor of the membrane attack complex (MAC). It binds the C5b-8 complex, blocking C9 polymerization and MAC pore formation, thereby protecting cells from complement-mediated lysis. CD59 expression is upregulated by NF-??B in response to TNF-?? and IL-6, linking innate immunity to complement resistance. The protein localizes to lipid rafts and interacts with C8, C9, and other GPI-anchored factors to maintain membrane integrity. Loss of CD59 leads to unrestricted MAC assembly and rapid CDC.
In SK-HEP-1 adenocarcinoma cells, CD59 knockout abrogates the primary complement defense, rendering them highly susceptible to antibody-mediated CDC. This model is critical for dissecting tumor immune evasion mechanisms, as many cancers upregulate CD59 to escape complement attack. It serves as a cell-based tool for evaluating therapeutic antibodies that activate complement, such as anti-CD20 or anti-EGFR antibodies, and for studying the interplay between complement and tumor-associated inflammation. Additionally, it facilitates validation of novel complement-targeted therapies.
This polyclonal knockout population is suited for flow cytometry, LDH-based cytotoxicity assays, western blotting, immunofluorescence, and antibody-dependent CDC experiments. Applications include complement regulation, cancer immunology, investigation of paroxysmal nocturnal hemoglobinuria-like phenotypes, and screening of complement-modulating compounds. Researchers can use the model to probe downstream consequences of complement activation loss and to identify strategies to overcome complement resistance. For further information, please contact Ascent Research.
