The TNFRSF21 Knockout ARPE-19 Cell Line is a CRISPR/Cas9-edited knockout cell line derived from ARPE-19 human retinal pigment epithelial cells. This cell line features disruption of the TNFRSF21 gene, encoding Death Receptor 6 (DR6), via CRISPR/Cas9-mediated gene disruption. The resulting loss-of-function model enables stable and specific investigation of DR6 signaling in a retinal epithelial context. It serves as a robust platform for apoptosis assays, signal transduction studies, and drug screening applications.
ARPE-19 is a spontaneously immortalized human retinal pigment epithelial cell line that retains key RPE functions, including tight junction formation, phagocytosis, and retinoid metabolism. These cells maintain photoreceptor health, support the visual cycle, and contribute to the outer blood?Cretinal barrier. ARPE-19 cells are extensively used to model retinal diseases such as age-related macular degeneration, study oxidative stress responses, and assess drug transport across the RPE. Their stable phenotype makes them well-suited for gene editing and long-term functional studies.
TNFRSF21 encodes DR6, a death receptor in the TNF receptor superfamily. DR6 is activated by amyloid precursor protein (APP)-derived ligands, ??-amyloid peptide, and TNF-??. Upon binding, DR6 recruits adaptors TRADD, FADD, RIP1, and TRAF2 to trigger downstream pathways. The primary signaling route leads to FADD-mediated caspase-8 activation and subsequent cleavage of caspase-3, resulting in apoptosis. Parallel activation of NF-??B and JNK pathways modulates cell survival and inflammatory gene expression. Key downstream effectors include JNK, NF-??B, and the pro-apoptotic factor Bax.
In ARPE-19 cells, DR6-mediated apoptosis and inflammation are relevant to retinal degenerative disease. The TNFRSF21 knockout enables dissection of DR6-dependent signaling in RPE cells, allowing separation of APP/TNF-?? effects from DR6-independent pathways. It provides a valuable tool for investigating RPE cell death mechanisms linked to age-related macular degeneration and for studying DR6 function in a non-neuronal context, beyond its known role in developmental axon pruning. This model also facilitates examination of cross-talk between apoptosis and survival pathways in RPE biology.
Common applications include western blot validation of DR6 knockout, caspase activity assays, flow cytometry for Annexin V staining, and RT-qPCR or immunofluorescence for downstream target analysis. Researchers can assess cell viability after ligand stimulation to screen compounds that modulate DR6-mediated apoptosis, and reconstitute wild-type or mutant DR6 for structure?Cfunction studies. This cell line supports drug discovery for retinal diseases and mechanistic studies of TNF receptor signaling. For further information, please contact Ascent Research.
