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Product Usage Information

Storage: Supplied in 10 mM sodium HEPES (pH 7.5), 150 mM NaCl, 100 µg/ml BSA and 50% glycerol. Store at –20°C. Do not aliquot the antibody.

Specificity / Sensitivity

MDR1/ABCB1 Antibody recognizes endogenous levels of total MDR1 protein. This antibody also cross-reacts with a 47 kDa protein of unknown origin in some cell lines.

Source / Purification

Polyclonal antibodies are produced by immunizing animals with a synthetic peptide corresponding to residues surrounding Glu643 of human MDR1 protein. Antibodies are purified by protein A and peptide affinity chromatography.

MDR1/ABCB1 belongs to the Mdr/Tap subfamily of the ATP-binding cassette transporter superfamily (1). Multidrug resistance 1 (MDR1) serves as an efflux pump for xenobiotic compounds with broad substrate specificity. MDR1 substrates include therapeutic agents such as actinomycin D, etoposide, imatinib, and doxorubicin, as well as endogenous molecules including β-amyloids, steroid hormones, lipids, phospholipids, cholesterol, and cytokines (2). Research studies have shown that MDR1 reduces drug accumulation in cancer cells, allowing the development of drug resistance (3-5). On the other hand, MDR1 expressed in the plasma membrane of cells in the blood-brain, blood-cerebral spinal fluid, or blood-placenta barriers restricts the permeability of drugs into these organs from the apical or serosal side (6,7). MDR1 is also expressed in normal tissues with excretory function such as small intestine, liver, and kidney (7). Intracellular MDR1 has been detected in the ER, vesicles, and nuclear envelope, and has been associated with cell trafficking machinery (8). Other reported functions of MDR1 include viral resistance, cytokine trafficking (9,10), and lipid homeostasis in the peripheral and central nervous system (11-13).

1.  Furuya, K.N. et al. (1997) Cancer Res 57, 3708-16.

2.  Litman, T. et al. (1997) Biochim Biophys Acta 1361, 169-76.

3.  Chen, C.J. et al. (1986) Cell 47, 381-9.

4.  Kartner, N. et al. (1983) Cancer Res 43, 4413-9.

5.  Chen, G. et al. (1997) J Biol Chem 272, 5974-82.

6.  Brinkmann, U. and Eichelbaum, M. (2001) Pharmacogenomics J 1, 59-64.

7.  Fromm, M.F. (2004) Trends Pharmacol Sci 25, 423-9.

8.  Miller, D.S. et al. (2008) Pharmacol Rev 60, 196-209.

9.  Ambudkar, S.V. et al. (1999) Annu Rev Pharmacol Toxicol 39, 361-98.

10.  Raviv, Y. et al. (2000) FASEB J 14, 511-5.

11.  Meijer, O.C. et al. (2003) J Endocrinol 178, 13-8.

12.  Karssen, A.M. et al. (2002) J Endocrinol 175, 251-60.

13.  Jeannesson, E. et al. (2009) Clin Chim Acta 403, 198-202.

Entrez-Gene Id 5243
Swiss-Prot Acc. P08183

For Research Use Only. Not For Use In Diagnostic Procedures.
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MDR1/ABCB1 Antibody