MDR-1/ABCB1 recombinant proteins and antibodies

Multidrug Resistance Protein 1 (MDR-1), also known as P-glycoprotein (P-gp), CD243, PGY1, is encoded by the ABCB1 gene and belongs to the ATP-binding cassette (ABC) transporter family. It functions as an ATP-dependent efflux pump widely expressed in intestinal epithelium, hepatocytes, renal tubules, and the blood–brain barrier. By actively transporting structurally diverse drugs out of cells using ATP hydrolysis, MDR-1 decreases intracellular drug accumulation, leading to multidrug resistance (MDR) in cancer and antiviral therapies.

Initially identified in oncology, MDR-1 plays a major role in chemoresistance across breast, colon, leukemia, and liver cancers. Early P-gp inhibitors aimed to reverse resistance but failed due to systemic toxicity and pharmacokinetic interference. Current research focuses on highly selective, low-toxicity next-generation inhibitors, and the modulation of MDR-1 to enhance drug delivery and blood–brain barrier permeability. MDR-1 has thus evolved from a resistance marker into a key ADME and CNS drug delivery target.

Globally, major pharmaceutical companies including Pfizer, Novartis, and Johnson & Johnson routinely evaluate P-gp substrate and inhibition profiles during early drug development to optimize bioavailability and CNS exposure. CROs such as AdmeScope and Solvo Biotechnology provide in vitro P-gp substrate/inhibitor assays for preclinical studies. Among ongoing programs, Tariquidar, a third-generation P-gp inhibitor, is being tested in clinical trials to reverse chemoresistance in solid tumors. In summary, MDR-1 serves as both a determinant of drug resistance and a strategic target for drug delivery optimization. Continued research into its transport mechanisms and regulatory networks will drive innovation in precision medicine, cancer therapy, and CNS drug development.

To assist in the development of MDR-1/ABCB1 targeted therapies, DIMA BIOTECH can now provide a full range of products and services for MDR-1 targets. Products include ECD recombinant proteins, the full-length membrane protein, reference antibodies, and flow-cytometry-verified anti-MDR-1 monoclonal antibodies; services include customized services for antibodies against multiple genus proteins, antibody humanization, and affinity maturation services. In addition, to accelerate the development of MDR-1 biotherapy, DIMA BIOTECH has also prepared a MDR-1 single B cell seed library, from which lead antibody molecules can be obtained in as fast as 28 days; at the same time, we have currently screened out multiple MDR-1 lead molecules, and customers can get the molecules for functional evaluation and verification the next day.