CD137L CRISPR Activation Plasmid (h): sc-404974-ACT

TNFSF9 encodes CD137L (4-1BBL), a TNF superfamily ligand expressed on antigen-presenting cells that engages CD137/TNFRSF9 on activated T cells and NK cells to amplify costimulatory signaling. CD137L–CD137 interactions promote immune synapse maturation, cytokine production, and survival programs through NF-κB and MAPK pathways, shaping cytotoxic and memory responses. This axis contributes to the regulation of inflammatory microenvironments and immune cell cross-talk in contexts such as autoimmunity, chronic infection, and tumor immunity, where altered costimulation can shift effector function and exhaustion. In addition, CD137L signaling can influence myeloid activation states and antigen presentation dynamics relevant to immunology and oncology research models.

CD137L CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous TNFSF9 expression without altering the underlying DNA sequence.

CD137L CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the TNFSF9 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 TNFSF9 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous CD137L expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native TNFSF9 locus and enabling the study of CD137L-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of CD137L pathway restoration in tumor cells with silenced or reduced TNFSF9 expression.

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