ABCB1 Knockout Huh-7 Polyclonal Cells are a CRISPR/Cas9-edited population of Huh-7 hepatocellular carcinoma cells with targeted disruption of the ABCB1 gene, eliminating P-glycoprotein (P-gp) expression. This polyclonal knockout pool provides a loss-of-function model to study hepatic drug efflux and multidrug resistance without requiring clonal selection. The heterogeneous nature of the pool captures the variability of gene editing events, suitable for broad pharmacological and toxicological assessments.
The Huh-7 host cell line is a well-differentiated human hepatoma line that retains key hepatocyte functions, including expression of drug-metabolizing enzymes and sinusoidal transporters. Its widespread use in liver biology, hepatitis C research, and drug metabolism studies makes it an ideal background for generating P-gp-deficient models. The cells exhibit epithelial morphology and stable growth, facilitating reproducible assays.
ABCB1 encodes P-glycoprotein, an ATP-dependent efflux pump that exports xenobiotics, chemotherapeutics, and endogenous metabolites across the canalicular membrane of hepatocytes. Its expression is transcriptionally regulated by the xenobiotic sensors NR1I2 (PXR) and NR1I3 (CAR), and is also influenced by HIF1A, NF-??B, and MAPK signaling. Substrate efflux by P-gp reduces intracellular drug concentrations, contributing to multidrug resistance. P-gp has broad substrate specificity, including anthracyclines, taxanes, vinca alkaloids, and immunosuppressants, making it a critical determinant of drug disposition. The transporter homodimerizes and functionally interacts with caveolin-1, ERM proteins, and NHERF1, which modulate its membrane localization. ABCB1 functions coordinately with ABCC1 (MRP1), CYP3A4, and UGT enzymes to form a detoxification network.
In Huh-7 cells, ABCB1 knockout abrogates the primary drug efflux mechanism, leading to increased retention of P-gp substrates such as doxorubicin, paclitaxel, and digoxin. This model enables direct investigation of chemosensitization strategies and the role of hepatic transporters in drug-induced liver injury, and to explore strategies for overcoming drug resistance in hepatocellular carcinoma. By comparing wild-type and knockout populations, researchers can delineate P-gp-mediated contributions to pharmacokinetics and hepatocellular toxicity.
Typical applications include multidrug resistance reversal studies, hepatocyte toxicology screening, and drug transport profiling. Assays such as rhodamine 123 or calcein-AM efflux, flow cytometry for surface P-gp, western blotting, RT-qPCR, and LC-MS/MS for intracellular drug quantification are routinely used. Cell viability assays (e.g., MTT) reveal altered chemosensitivity. These polyclonal knockout cells provide a versatile and cost-effective model for many routine pharmacological applications, especially where population heterogeneity better reflects in vivo conditions. For further technical details or to discuss custom projects, please contact Ascent Research.
