Qa-1 Lentiviral Activation Particles (m): sc-420781-LAC

Mouse H2-T23 encodes Qa-1, a nonclassical MHC class I molecule that presents a restricted peptide repertoire and modulates immune recognition by interacting with inhibitory and activating receptors on NK cells and subsets of CD8 T cells. Qa-1 contributes to immune tolerance and surveillance by shaping cytotoxic responses and influencing antigen presentation dynamics within the broader MHC class I pathway. Altered Qa-1/H2-T23 expression has been associated with changes in inflammatory tone, immune evasion, and regulation of autoreactive responses, making it relevant to studies of infection, tumor immunology, and autoimmune-like phenotypes. As a model antigen-presenting regulator, Qa-1 is frequently used to interrogate NK–T cell cross-talk, stress-induced immune signaling, and immune checkpoint-like mechanisms in mice.

Qa-1 Lentiviral Activation Particles (m) address this need by packaging the complete synergistic activation mediator (SAM) transcriptional activation system into transduction-ready, high-titer lentiviral particles, enabling efficient H2-T23 upregulation across a broader range of human cell types.

Qa-1 Lentiviral Activation Particles (m) deliver all functional components of the synergistic activation mediator (SAM) system via lentiviral transduction. The system comprises three particle preparations co-transduced into target cells: one encoding catalytically inactive dCas9 (D10A and N863A mutations) fused to the VP64 transactivation domain with a blasticidin resistance gene; one encoding the MS2-p65-HSF1 fusion protein with a hygromycin resistance gene; and one encoding a target-specific 20 nt sgRNA fused to two MS2 RNA aptamers with a puromycin resistance gene. Following lentiviral transduction and genomic integration of the expression cassettes, the SAM components are stably expressed and assemble at the target locus within the proximal promoter region upstream of the H2-T23 transcriptional start site, where VP64, p65, and HSF1 act cooperatively to recruit endogenous transcriptional machinery and drive sustained upregulation of endogenous Qa-1 expression. The use of nuclease-inactive dCas9 avoids the introduction of double-strand DNA breaks and preserves the native H2-T23 genomic locus and regulatory architecture.

The lentiviral format offers several practical advantages: stable genomic integration supports heritable activation across cell divisions; high-titer particle preparations eliminate the need for in-house viral production; and compatibility with primary, non-dividing, and transfection-resistant cell types expands experimental accessibility. Successful transduction can be confirmed and enriched through triple antibiotic selection using puromycin, hygromycin, and blasticidin.

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