Variability in mRNA expression of ABC- and SLC-transporters in human intestinal cells: comparison between human segments and Caco-2 cells

Eur J Pharm Sci. 2006 Jul;28(4):291-9. doi: 10.1016/j.ejps.2006.03.003. Epub 2006 Mar 22.


The Caco-2 cell monolayer model is widely used as a tool for evaluating human intestinal permeability and interaction with transporters. Therefore, we determined mRNA levels for 15 of the most frequently studied uptake and efflux transporters (MDR1, MRP2-3, BCRP, OCTN2, PepT1, OATP-B, OATP8, OCT1-3, OAT1-3, MCT1) using real-time PCR in Caco-2 cells and in human jejunum and colon. The expression levels in the Caco-2 cells did not significantly vary between different passages (p29-43) and batches for any of the genes measured. However, levels increased with culture time (1-5 weeks) for PepT1, MDR1, MRP2, OATP-B and BCRP. The general rank order of the gene expression levels in Caco-2 cells was established as follows: MRP2>OATP-B>PepT1>>MDR1>MCT1 approximately MRP3 approximately BCRP approximately OCTN2>>OCT3>OCT1>OAT2. Four genes were absent: OATP8, OCT2, OAT1, and OAT3. Ranking of 11 expressed genes showed a significant correlation between human jejunum and 2-5-week-old Caco-2 cells. The expression profile in colon was, however, very different compared to both Caco-2 cells and jejunum. We conclude that the Caco-2 cells in our hands express similar transporters as the human jejunum, but are different from colon, indicating their usefulness for obtaining small intestinal transport data. In addition, we also suggest that cells with a well-defined range of culture ages should be used to minimize variability in data from experiments and even erroneous conclusions.

Publication types

  • Comparative Study

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B, Member 1 / genetics
  • ATP Binding Cassette Transporter, Subfamily B, Member 1 / metabolism
  • ATP-Binding Cassette Transporters / genetics
  • ATP-Binding Cassette Transporters / metabolism*
  • Caco-2 Cells
  • Colon / cytology
  • Colon / metabolism*
  • Gene Expression Regulation*
  • Humans
  • Intestinal Mucosa / metabolism
  • Jejunum / cytology
  • Jejunum / metabolism*
  • Membrane Transport Proteins / genetics
  • Membrane Transport Proteins / metabolism
  • Multidrug Resistance-Associated Protein 2
  • Multidrug Resistance-Associated Proteins / genetics
  • Multidrug Resistance-Associated Proteins / metabolism
  • Organic Anion Transporters / genetics
  • Organic Anion Transporters / metabolism*
  • RNA, Messenger / metabolism*
  • Reproducibility of Results
  • Reverse Transcriptase Polymerase Chain Reaction / methods
  • Time Factors


  • ABCC2 protein, human
  • ATP Binding Cassette Transporter, Subfamily B, Member 1
  • ATP-Binding Cassette Transporters
  • Membrane Transport Proteins
  • Multidrug Resistance-Associated Protein 2
  • Multidrug Resistance-Associated Proteins
  • Organic Anion Transporters
  • RNA, Messenger
  • SLCO2B1 protein, human