The CD59 Knockout A-549 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout population derived from the A-549 human lung adenocarcinoma cell line, featuring targeted disruption of the CD59 gene. This loss-of-function model eliminates the protective function of CD59 against complement-mediated lysis, providing a heterogeneous cell pool that avoids clonal selection artifacts and better reflects the diversity of tumor cell populations. The use of a polyclonal editing strategy ensures robust representation of various knockout genotypes, making this product suitable for studies requiring population-level complement sensitivity assessments.
A-549 cells, originally isolated from a 58-year-old Caucasian male with lung adenocarcinoma, are a well-established model for non-small cell lung cancer (NSCLC). These epithelial cells grow adherently, exhibit KRAS and EGFR mutations typical of the disease, and are extensively used in cancer biology and drug development studies. Their genetic tractability and physiological relevance make them an ideal host for introducing gene disruptions to probe mechanisms of immune resistance.
CD59 functions as a key terminal inhibitor of the complement cascade by binding to complement components C8 and C9 within the assembling membrane attack complex (MAC), thus preventing C9 polymerization and pore formation. Its expression is upregulated by proinflammatory cytokines TNF-?? and IL-1?? and by transcription factors STAT3 and HIF-1??. At the membrane, CD59 associates with lipid rafts and interacts with Src family kinases and Lck, linking complement defense to intracellular signaling pathways. Alongside other regulators such as CD55 and CD46, CD59 plays a pivotal role in averting complement-dependent cytotoxicity. In the knockout cells, ablation of CD59 eliminates this inhibitory checkpoint, sensitizing cells to MAC assembly and lysis??a mechanistic foundation for exploring complement-mediated anti-tumor responses.
In A-549 lung adenocarcinoma, CD59 overexpression contributes to immune evasion by protecting tumor cells from complement attack. The CD59 knockout in this context exposes a vulnerability that can be exploited to study complement-dependent cytotoxicity as a therapeutic strategy. The polyclonal nature of the knockout further enables the assessment of heterogeneity in complement resistance, offering a more realistic model than isogenic clones. This system is particularly valuable for evaluating the efficacy of antibody-based therapies that rely on complement activation for cancer cell killing.
Typical applications include complement-dependent cytotoxicity assays with human serum, flow cytometric detection of C9 deposition, Western blotting to verify CD59 loss, and RT-qPCR profiling of complement regulator expression. It is also suitable for drug screening of complement modulators, investigation of immune evasion pathways, and development of immunotherapeutic strategies that harness complement. For further technical details or custom orders, please contact Ascent Research.
