Western Blot analysis of Abcb1a/b expression. Western Blot analysis was performed to verify Abcb1a/Abcb1b RealTime-PCR data and clearly show that the ABC multidrug transporters were markedly up-regulated in mBMDC/67NR-Hyg clones. The used antibody recognizes both Abcb1 isoforms. β-actin served as a loading control. Numbers indicate the relative Abcb1a/b expression levels in relation to β-actin, whereby Abcb1a/b expression levels of BMDCs were set to 100%.