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Molecular structure and tissue distribution
OATP1B3 (previously known as OATP8) is highly expressed in liver where it mediates the uptake of many different drugs from blood into hepatocytes. Together with the other three members (OATP1B1, OATP1A2, OATP1C1) of the human OATP1 subfamily OATP1B3 is localized on the short arm of chromosome 12 (12p12). The OATP1B3 protein has a length of 702 amino acids.

Interaction of OATP1B3 with endogenous compounds and drugs

Endogenous compounds that are transported by OATP1B3 are bile salts like taurocholate. Sulfobromophthalein (BSP) is used as model substrate. Because OATP1B3 and OATP1B1 have a nearly consistent substrate spectrum, most of the drugs identified as substrates for OATP1B1 are also transported by OATP1B3. Substrates of OATP1B3 include the statins fluvastatin, pravastatin and pitavastatin and, for example, the cytostatic drug methotrexate.

Figure 1 Time dependency experiments with sulfobromophthalein (BSP) for OATP1B3. Figure 2 Inhibition of OATP substrates by rifampicin.



New validated products:

  • mNtcp
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3rd German Pharm-Tox Summit
Göttingen, Germany
26 February - 1 March 2018

Saarbrücken, Germany
8 March 2018


AAPS Workshop
Virginia, USA
16 - 18 April 2018


20th Barrier- and

Bad Herrenalb, Germany
7 - 9 May 2018

Greifswalder Transporttage 2018
Greifswald, Germany
October 2018


Guidance for Industry (FDA and EMA)