SIGLEC5/NFκB Reporter Lentivirus

Background

SIGLEC5 (sialic acid-binding immunoglobulin-like lectin 5) is an inhibitory receptor of the Siglec family expressed mainly on myeloid cells, including neutrophils, monocytes, and macrophages. Through ITIM motifs in its cytoplasmic tail, SIGLEC5 transduces inhibitory signals upon engaging sialylated glycan ligands, helping to restrain myeloid cell activation and inflammatory responses. Tumors can exploit Siglec receptors by displaying altered sialoglycans, contributing to immune evasion and modulation of macrophage function. SIGLEC5 signaling intersects with the NF-κB pathway, so NF-κB response elements provide a quantitative readout, and SIGLEC5 is of growing interest as a target in cancer immunology.

Product Description & Applications

The SIGLEC5/NFκB Reporter Lentivirus is a two-vial immunotherapy reporter system for studying SIGLEC5 signaling and myeloid cell regulation. One vial constitutively expresses the human SIGLEC5 receptor with an antibiotic selection marker, while the other carries tandem NF-κB response elements driving a dual reporter combining secreted Gaussia luciferase (GLuc) and a fluorescent protein (GFP or RFP). Sequential transduction and selection generate a dual-stable cell line that responds quantitatively to receptor engagement. Secreted GLuc accumulates in conditioned media for kinetic, lysis-free sampling, while the fluorescent reporter enables microscopy and flow cytometry. Applications include tumor immune evasion assays and studies of macrophage regulation and tumor immunology. Supplied as high-titer, VSV-G-pseudotyped third-generation lentiviral particles purified by PEG precipitation and sucrose gradient centrifugation.

About This Product

This 2-vial immunotherapy reporter system consists of a Vial 1 Receptor Lentivirus encoding human SIGLEC5 under a constitutive promoter with antibiotic selection, and a Vial 2 Reporter Lentivirus encoding tandem NFAT (or NF-κB) response elements driving a dual reporter (GFP, GFP-P2A-GLuc, GLuc, GLuc-P2A-GFP, GLuc-P2A-RFP, RFP, RFP-P2A-GLuc). Sequential transduction and selection generates a dual-stable effector cell line that responds quantitatively to receptor stimulation with a ratiometric fluorescent + bioluminescent readout.

Secreted Gaussia luciferase (where included) accumulates in conditioned media, enabling kinetic sampling without cell lysis. The combined fluorescent and luminescent outputs allow parallel microscopy-based visualization and plate-reader luminometry from the same cell population — providing assay redundancy and flexibility for potency testing formats compliant with regulatory expectations for cell-based functional assays.