CD274/PD-L1 CRISPR Activation Plasmid (m): sc-425636-ACT

Cd274 encodes CD274/PD-L1, an immunoregulatory type I transmembrane protein that binds PD-1 (Pdcd1) and modulates T cell receptor signaling to constrain effector function, cytokine production, and cytotoxic activity. In mouse, PD-L1 expression is induced by inflammatory cues such as IFN-γ through JAK/STAT signaling and is shaped by pathways including NF-κB and PI3K–AKT, integrating innate and adaptive immune responses. PD-L1 contributes to peripheral tolerance and immune homeostasis by limiting excessive activation, while altered expression in tumors and chronically inflamed tissues is associated with immune evasion and dysfunctional T cell states. These features make Cd274 a central node for studying immune checkpoint biology, antigen presentation contexts, and crosstalk between stromal, myeloid, and lymphoid compartments.

CD274/PD-L1 CRISPR Activation Plasmid (m) provides a targeted, non-destructive approach to upregulating endogenous Cd274 expression without altering the underlying DNA sequence.

CD274/PD-L1 CRISPR Activation Plasmid (m) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the Cd274 locus in human cell lines. The system is built around a catalytically inactive Cas9 (dCas9) carrying two inactivating mutations (D10A and N863A) that eliminate nuclease activity while preserving DNA binding. This dCas9 is fused to VP64, a potent transcriptional activator, and is co-expressed with a blasticidin resistance gene for selection. The second plasmid encodes the MS2-p65-HSF1 fusion protein, a secondary activator complex that works in concert with dCas9-VP64, alongside a hygromycin resistance gene. The third plasmid encodes a target-specific 20 nt sgRNA fused to two MS2 RNA aptamers that recruit the MS2-p65-HSF1 complex to the activation site, accompanied by a puromycin resistance gene. The three plasmids are delivered at a 1:1:1 mass ratio for balanced expression of all system components.

Once assembled at the target locus, the SAM complex binds within approximately 200 bp upstream of the Cd274 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous CD274/PD-L1 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native Cd274 locus and enabling the study of CD274/PD-L1-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of CD274/PD-L1 pathway restoration in tumor cells with silenced or reduced Cd274 expression.

For Research Use Only. Not Intended for Diagnostic or Therapeutic Use.