The TLR7/NF-κB Luciferase Reporter HEK293 Stable Cell Line is derived from human embryonic kidney (HEK293) cells and is stably transfected to express full-length human Toll-like receptor 7 (TLR7) together with a firefly luciferase reporter gene under the transcriptional control of an NF-κB response element. The functional activity of this cell line has been validated using a TLR7 ligand assay. Upon stimulation with R848 (Resiquimod), TLR7 activation rapidly initiates the TRIF-dependent signaling pathway, leading to nuclear translocation of NF-κB and a corresponding increase in luciferase activity.
 
Toll-like receptor 7 (TLR7) is a pattern recognition receptor of the innate immune system that detects double-stranded RNA (dsRNA), a molecular signature commonly associated with viral infection. TLR7 is primarily localized in endosomal compartments, where it recognizes dsRNA derived from viruses or synthetic analogs such as R848 (Resiquimod).
 
The cell line was established by co-transfection with a pCMV-TLR7 expression vector, an NF-κB–driven firefly luciferase reporter vector, and a G418 resistance vector, followed by selection with G418. Hygromycin-resistant clones were subsequently screened for R848 (Resiquimod)-induced luciferase activity.