The CD274 Knockout SK-OV-3 Polyclonal Cells constitute a CRISPR/Cas9-edited polyclonal knockout cell population in the SK-OV-3 human ovarian adenocarcinoma cell line, designed to eliminate expression of the CD274 gene (encoding programmed death-ligand 1, PD-L1). This polyclonal pool, generated by CRISPR/Cas9-mediated gene disruption, provides a defined loss-of-function model for investigating PD-L1-dependent immune checkpoint regulation in ovarian cancer without introducing clonal bias.
The SK-OV-3 cell line, derived from the ascites of a patient with ovarian adenocarcinoma, exhibits epithelial morphology and is widely employed as a model system for ovarian cancer biology. These cancerous epithelial cells harbor genetic and phenotypic characteristics relevant to high-grade serous ovarian carcinoma, including dysregulated signaling pathways and immune evasion capabilities, making them a suitable host for studying tumor cell-intrinsic mechanisms and interactions with the immune microenvironment.
CD274 encodes PD-L1, a transmembrane immune checkpoint ligand that interacts primarily with the PD-1 receptor (PDCD1) on activated T cells, delivering inhibitory signals that suppress T-cell receptor (TCR) signaling and promote immune evasion. PD-L1 expression is upregulated by IFN-?? through JAK/STAT signaling, as well as by oncogenic drivers such as MYC, HIF-1??, and EGFR. Upon binding PD-1, PD-L1 recruits the SHP-2 phosphatase, which dephosphorylates key TCR-proximal kinases including ZAP70, thereby dampening downstream PI3K/AKT and MAPK/ERK cascades. Additionally, PD-L1 can engage CD80 (B7-1) in cis or trans, further modulating immune responses. Disruption of CD274 thus ablates PD-L1 surface expression, preventing PD-1 ligation and releasing T-cell activation from checkpoint-mediated inhibition.
In SK-OV-3 ovarian adenocarcinoma cells, which actively engage immune evasion mechanisms, loss of PD-L1 provides a clean genetic background to dissect tumor-intrinsic roles of CD274. Ovarian carcinoma frequently exhibits elevated PD-L1 expression correlating with poor prognosis and immune escape; this knockout model therefore enables investigation of how PD-L1 deficiency alters tumor cell signaling, proliferation, and sensitivity to immune effector cells. Co-culture with antigen-specific T cells can reveal restoration of IFN-?? secretion and enhanced tumor cell killing upon PD-L1 ablation, making these polyclonal cells valuable for assessing the functional impact of checkpoint disruption in a physiologically relevant cellular context.
Researchers can employ these cells in diverse experimental workflows, including western blotting and flow cytometry to confirm PD-L1 protein loss, RT-qPCR to quantify CD274 transcript ablation, and functional co-culture assays with primary T cells to measure changes in cytokine secretion and tumor cell apoptosis. The polyclonal population enables robust assessment of PD-L1-dependent phenotypes in migration, drug sensitivity, and immune checkpoint blockade studies, circumventing the limitations of single-cell clones. These cells are particularly suited for screening small-molecule inhibitors or therapeutic antibodies targeting PD-L1 in an ovarian cancer context and for studying upstream regulators such as IFN-?? and HIF-1??. For further customizations or technical support, please contact Ascent Research.
