HLA-DQA1 CRISPR Activation Plasmid (h): sc-403480-ACT

HLA-DQA1 encodes the alpha chain of the HLA-DQ heterodimer, a major histocompatibility complex (MHC) class II molecule expressed primarily on antigen-presenting cells. In the endosomal antigen processing and presentation pathway, HLA-DQ binds peptide antigens and displays them at the cell surface to CD4+ T cells, shaping adaptive immune activation, tolerance, and cytokine-driven immune polarization. Variation in HLA-DQA1 influences peptide-binding specificity and has been linked to altered immune recognition in autoimmune and inflammatory contexts, including celiac disease and type 1 diabetes. As a locus within the HLA region, it is widely studied for effects on immune repertoire, antigen-specific T cell responses, and immunogenetic risk architectures.

HLA-DQA1 CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous HLA-DQA1 expression without altering the underlying DNA sequence.

HLA-DQA1 CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the HLA-DQA1 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 HLA-DQA1 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous HLA-DQA1 expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native HLA-DQA1 locus and enabling the study of HLA-DQA1-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of HLA-DQA1 pathway restoration in tumor cells with silenced or reduced HLA-DQA1 expression.

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