The CD59 Knockout HT29 Polyclonal Cells comprise a CRISPR/Cas9-edited polyclonal population derived from the HT29 human colon adenocarcinoma epithelial cell line, engineered to disrupt the CD59 gene. This polyclonal knockout cell pool offers a genetically heterogeneous loss-of-function model for studying complement regulation, immune evasion, and epithelial tumor biology. The targeted disruption abolishes CD59 protein expression, eliminating its complement-inhibitory function without selection for a single clonal genotype.
The HT29 cell line, established from a human colorectal adenocarcinoma, serves as a well-characterized model for intestinal epithelial function and colorectal cancer research. These adherent epithelial cells retain many features of colonic epithelium, including the ability to form polarized monolayers and express intestinal markers, making them suitable for studies of barrier function, tumor biology, and host?Cpathogen interactions. Their wide use in cancer and epithelial research provides a robust background for examining the consequences of complement regulatory gene knockout.
CD59 is a glycosylphosphatidylinositol (GPI)-anchored complement regulatory protein that protects host cells from complement-mediated lysis by binding to complement components C8 and C9 and preventing the polymerization of C9, thereby inhibiting the formation of the cytolytic membrane attack complex (MAC). Its expression is upregulated by complement activation and inflammatory cytokines. Functionally, CD59 acts downstream of the assembly of the C5b-8 complex, directly impeding the incorporation and polymerization of C9, which blocks MAC pore formation. Consequently, CD59 deficiency leads to increased deposition of C5b-9 and enhanced susceptibility to complement-induced cell death and pro-inflammatory signaling.
In the context of HT29 colorectal adenocarcinoma cells, CD59 knockout provides a powerful tool to dissect the role of complement evasion in cancer. Colorectal tumors often upregulate complement regulators to resist complement-mediated attack; therefore, disrupting CD59 in this background allows investigation of how loss of this protective mechanism affects tumor cell survival, complement-dependent cytotoxicity, and immune evasion. This model also serves as a relevant system for studying paroxysmal nocturnal hemoglobinuria (PNH)-like phenotypes, complement-mediated hemolysis, and the broader innate immune response in an epithelial cancer setting.
Researchers can employ this polyclonal CD59 knockout HT29 population in a range of functional assays, including complement-mediated cytotoxicity assays to quantify cell lysis, flow cytometry for surface CD59 validation, western blotting and RT-qPCR for expression analysis, and C5b-9 immunofluorescence to visualize MAC deposition. Applications extend to screening therapeutic complement inhibitors, evaluating antibody-dependent complement-mediated tumor cell killing, and investigating the interplay between complement and cancer immune surveillance. For further information, please contact Ascent Research.
