Partial external biliary diversion in bile salt export pump deficiency: Association between outcome and mutation

Figure 2 Immunofluorescence studies. A: Liver biopsy from the female patient possessing the BSEP-T919del mutation. (I) Immunoreactivity of BSEP (K24-antibody) was apparently normal as compared to the bilirubin transporter multidrug resistance- associated protein 2 (MRP2; M2I-4- and M2III-6-antibodies). (II) Immunoreactivity of MDR3 (P3II-26-antibody) showed a typical canalicular pattern similar to MRP2 (EAG5-antibody). Liver biopsy from the male patient (p.G1032R mutation) shows an almost regular BSEP expression (K24-antibody) and MDR3 (III) and MRP2 (IV); B: Wild-type BSEP is largely expressed at the cell membrane of human embryonic kidney (HEK293) cells. Likewise, both BSEP mutants, with deletion of threonine at position 919 (p.T919del) and with arginine instead of glycine at amino acid position 1032 (p.G1032R), are localized at the plasma membrane (Bars = 5 μm). BSEP: Bile salt export pump.