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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:

  • MRP2
  • roct1


2nd German Pharm-Tox Summit
Heidelberg, Germany
March 06-09, 2017

19th Barrier- and

Bad Herrenalb, Germany
May 15-17, 2017

14th European ISSX Meeting
Köln, Germany

June 26- 29, 2017

2nd Symposium on Transporters in Drug Discovery
London, UK
May 15-16, 2017

Münster Transporttage 2017
Münster, Germany
October 21 – 22, 2017


Guidance for Industry (FDA and EMA)