Differences in P-glycoprotein-170 expression and activity between Crohn's disease and ulcerative colitis

Hum Immunol. 1999 Aug;60(8):677-87. doi: 10.1016/s0198-8859(99)00036-1.


The clinical benefit of Cyclosporine A (CsA) in IBD is controversial. Drugs including CsA are substrates of the P-glycoprotein-170 (Pgp-170) cell surface pump. Although the mechanism of action of CsA is complex, we determined that Pgp-170 might be expressed differentially between these two diseases. Intra-epithelial, lamina propria and peripheral blood lymphocytes were stained with the antibody MRK-16, which recognizes the surface antigen Pgp-170. Functional activity was assayed using a Rhodamine dye efflux assay (Rh123). RT-PCR was used to detect Pgp-170 mRNA. Overall, less P-gp-170 surface expression was found on UC CD3+ intestinal lymphocytes compared to controls and Crohn's disease. A decrease in Pgp-170 activity was also measured using the Rh123 functional assay. Fewer CD8+ intraepithelial lymphocytes (IEL) (which intrinsically have more Pgp-170 function) were also found in UC. Furthermore, UC IEL P-gp expression was under the limit of detection by RT-PCR. Overall, greater and differential expression, function and mRNA for Pgp-170 was found in Crohn's disease compared to the UC and normal tissues analyzed.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B, Member 1 / genetics
  • ATP Binding Cassette Transporter, Subfamily B, Member 1 / metabolism*
  • Adult
  • CD3 Complex / genetics
  • CD3 Complex / metabolism
  • CD4-Positive T-Lymphocytes / immunology
  • CD4-Positive T-Lymphocytes / metabolism
  • CD8-Positive T-Lymphocytes / immunology
  • CD8-Positive T-Lymphocytes / metabolism
  • Colitis, Ulcerative / immunology
  • Colitis, Ulcerative / metabolism*
  • Crohn Disease / immunology
  • Crohn Disease / metabolism*
  • Humans
  • Intestinal Mucosa / immunology*
  • Leukocytes, Mononuclear / immunology
  • Leukocytes, Mononuclear / metabolism*
  • Lymphocytes / immunology
  • Lymphocytes / metabolism*
  • Middle Aged
  • RNA, Messenger / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction / methods


  • ATP Binding Cassette Transporter, Subfamily B, Member 1
  • CD3 Complex
  • RNA, Messenger