ICSBP CRISPR Activation Plasmid (h): sc-400774-ACT

Human IRF8 encodes the interferon consensus sequence-binding protein (ICSBP), a hematopoietic-restricted transcription factor that cooperates with IRF and ETS family partners to regulate myeloid and B cell lineage specification, antigen presentation, and interferon-stimulated gene programs. ICSBP integrates signals from interferon, TLR, and cytokine pathways to shape innate and adaptive immune responses, including macrophage activation and dendritic cell differentiation. Dysregulated IRF8 activity has been associated with altered immune cell development, inflammatory phenotypes, and susceptibility to immune-mediated disorders, and it is frequently studied in the context of hematologic malignancy biology. As a nodal regulator of transcriptional networks, IRF8 provides a tractable entry point for dissecting gene regulatory circuits controlling immune homeostasis.

ICSBP CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous IRF8 expression without altering the underlying DNA sequence.

ICSBP CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the IRF8 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 IRF8 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous ICSBP expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native IRF8 locus and enabling the study of ICSBP-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of ICSBP pathway restoration in tumor cells with silenced or reduced IRF8 expression.

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