LILRB4/NFAT Reporter Lentivirus

Background

LILRB4 (leukocyte immunoglobulin-like receptor B4, also known as ILT3) is an inhibitory immune receptor expressed mainly on myeloid cells, including monocytes, macrophages, and dendritic cells. Through ITIM motifs in its cytoplasmic tail, LILRB4 transmits inhibitory signals that suppress myeloid cell activation and promote immune tolerance. LILRB4 is also highly expressed on monocytic acute myeloid leukemia cells, where it supports immune evasion and tumor infiltration. Because LILRB4 engagement dampens NFAT-dependent transcription, NFAT-driven reporters provide a quantitative readout of its signaling, and LILRB4 is an emerging target for antibody-based cancer immunotherapy.

Product Description & Applications

The LILRB4/NFAT Reporter Lentivirus is a two-vial immunotherapy reporter system for investigating LILRB4-mediated immune suppression in myeloid cells. One vial constitutively expresses the human LILRB4 receptor with an antibiotic selection marker, while the other carries tandem NFAT 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 effector cell line in which ligand engagement suppresses NFAT-driven reporter output. Secreted GLuc enables kinetic, lysis-free sampling from conditioned media, while the fluorescent reporter supports microscopy and flow cytometry. Applications include studying immune suppression, myeloid cell responses, and antibodies that relieve LILRB4 inhibition. Supplied as high-titer, VSV-G-pseudotyped third-generation lentiviral particles optimized for primary or thawed myeloid cells.

About This Product

This 2-vial immunotherapy reporter system consists of a Vial 1 Receptor Lentivirus encoding human LILRB4 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.