The CD46 Knockout HT29 Polyclonal Cells are a CRISPR/Cas9-edited polyclonal knockout cell population generated from the human colorectal adenocarcinoma cell line HT29, in which the CD46 gene has been functionally disrupted to ablate expression of the membrane cofactor protein CD46. This polyclonal knockout model provides a heterogeneous pool of edited cells, enabling researchers to investigate CD46-dependent processes in a widely used intestinal epithelial background. The product is designed as a loss-of-function tool for studying complement regulation, pathogen entry, immune modulation, and tumor cell biology, and is validated for absence of CD46 surface expression by flow cytometry. All procedures are performed under rigorous quality control to ensure reproducibility in downstream functional assays.
HT29 cells are derived from a human colon adenocarcinoma and exhibit adherent epithelial morphology. They harbor a BRAF V600E activating mutation and a TP53 tumor suppressor mutation, reflecting genetic alterations commonly observed in colorectal carcinomas. HT29 cells serve as a well-characterized model of intestinal epithelium and are extensively employed in studies of colorectal cancer biology, epithelial barrier function, and drug transport. Their robust growth and compatibility with standard culture conditions make them a reliable host for gene disruption experiments, and their molecular profile provides a relevant context for assessing tumor cell responses to immune surveillance and therapeutic interventions.
CD46, also known as membrane cofactor protein, is a type I membrane glycoprotein that functions as a critical regulator of the complement cascade. It acts as a cofactor for the serine protease factor I, enabling proteolytic cleavage and inactivation of C3b and C4b deposited on host cell surfaces, thereby preventing formation of C3 convertase and the membrane attack complex. Beyond complement regulation, CD46 serves as a cellular receptor for measles virus hemagglutinin and adenovirus fiber protein, mediating pathogen entry. It also participates in modulating T-cell immunity through interactions with ??1 integrin and DLG1, and regulates autophagy via LC3. CD46 expression is transcriptionally controlled by pro-inflammatory cytokines such as TNF-??, IFN-??, and IL-1??, acting through NF-??B and STAT1 signaling. Upon ligand engagement, CD46 triggers downstream activation of Src family kinases, Vav, Rac, and the PI3K-Akt pathway, resulting in immunomodulatory outputs including IL-10 production.
In the HT29 colorectal adenocarcinoma background, disruption of CD46 eliminates its protective complement-regulatory function, rendering the cells more susceptible to complement-mediated lysis. This sensitization provides a robust system for studying complement-dependent cytotoxicity and for evaluating therapeutic antibodies that rely on complement activation. Moreover, loss of CD46 disrupts its receptor role for measles virus and adenoviruses, enabling dissection of virus?Chost cell interactions. Given HT29??s BRAF and TP53 mutations, this knockout model also allows exploration of crosstalk between oncogenic signaling and CD46-mediated immune evasion, T-cell regulation, and autophagy in the context of colorectal cancer, where CD46 is often overexpressed.
This polyclonal knockout cell line supports diverse research applications, including complement-dependent cytotoxicity assays to assess antibody efficacy, virus binding and entry assays for measles and adenovirus, and autophagy flux analyses using LC3 readouts. It is also suitable for T-cell co-culture experiments to examine immune regulation and IL-10 secretion, and for mechanistic studies on CD46 downstream signaling involving Src, Vav, Rac, and Akt. Common readouts include flow cytometric detection of CD46 surface expression, western blotting, RT-qPCR, and functional cytotoxicity endpoints. For further details or customized inquiries, please contact Ascent Research.
