The CD274 Knockout 786-O Polyclonal Cells constitute a CRISPR/Cas9-mediated gene-disrupted polyclonal population specifically targeting the CD274 locus in the human 786-O clear cell renal cell carcinoma line. This product delivers a heterogeneous pool of cells collectively lacking functional PD-L1 protein, providing a robust loss-of-function model for studying immune checkpoint biology without the constraints of clonal selection. The polyclonal format preserves genetic diversity while ensuring consistent ablation of PD-L1-mediated signaling.
The parental 786-O cell line is derived from a renal cell adenocarcinoma and serves as an essential model for clear cell renal cell carcinoma (ccRCC). A hallmark of this line is an inactivating mutation in the von Hippel-Lindau (VHL) tumor suppressor gene, which results in constitutive stabilization of hypoxia-inducible factor 1-alpha (HIF-1??) and subsequent transcriptional activation of numerous hypoxia-responsive genes, including CD274. This feature recapitulates the pseudohypoxic microenvironment typical of aggressive ccRCC.
The CD274 gene product, PD-L1, is an immune checkpoint ligand upregulated by cytokines such as IFN-?? and TNF-?? via JAK-STAT and NF-kB pathways, with STAT1, STAT3, and NF-kB as key transcription factors. HIF-1?? further drives expression under hypoxia, especially in VHL-mutant cells. PD-L1 binds PD-1 on T cells, recruiting SHP-2 to inhibit PI3K-AKT and JAK-STAT signaling, resulting in T cell exhaustion and immune evasion.
In the VHL-mutant 786-O line, CD274 knockout enables dissection of PD-L1??s tumor-intrinsic role in immune suppression, independent of other HIF-1?? targets. This allows investigation of how PD-L1 cooperates with oncogenic pathways like PI3K-AKT and RAS-MYC to promote an immunosuppressive microenvironment, making it a focused model for ccRCC immunotherapy research.
The knockout polyclonal population supports T cell co-culture assays for proliferation and cytokine release, PD-L1 inhibitor screening, and cytokine stimulation studies (IFN-??, TNF-??). Standard techniques include flow cytometry, co-immunoprecipitation, and luciferase reporter assays for NF-kB or STAT3. In vivo xenograft models are also applicable. For further technical inquiries, please contact Ascent Research.
