Human dipeptide transporter, hPEPT1, stably transfected into Chinese hamster ovary cells

Pharm Res. 1996 Nov;13(11):1631-4. doi: 10.1023/a:1016476220296.


Purpose: A cDNA encoding the H(+)-coupled peptide transporter, hPEPT1, has previously been cloned from human ileum (8). The objective of this study was to establish a stably transfected cell line expressing hPEPT1 in mammalian cell culture.

Methods: The hPEPT1 cDNA was subcloned into an expression vector carrying the CMV promoter and a neomycin resistance gene. This vector, pCDNA3-PEPT1, was transiently transfected into several cell lines to identify those capable of expressing PEPT1 transport function. CHO cells were selected and stably transfected with PEPT1 (CHO-PEPT1). Dipeptide transport activity was measured with 3H-Gly-Sar, in the presence and absence of inhibitors.

Results: The clonal cell line, CHO-PEPT1, displayed high transport activity. Dipeptide transport was sensitive to pH and specific for dipeptides and other small peptides. Peptidomimetic antibiotics, such as cephalexin, were competitors for peptide transport.

Conclusions: The stably transfected cell line, CHO-PEPT1 exhibits enhanced transport over that of cell lines with native expression of PEPT1, and therefore, represents a useful tool for rapid screening of drugs that utilize the peptide transporter in the human intestine for absorption.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Ampicillin / pharmacology
  • Animals
  • Biological Transport / drug effects
  • CHO Cells / drug effects
  • CHO Cells / metabolism
  • CHO Cells / physiology*
  • COS Cells
  • Carrier Proteins / biosynthesis
  • Carrier Proteins / genetics*
  • Carrier Proteins / metabolism*
  • Cephalexin / pharmacology
  • Cephalosporins / pharmacology
  • Clone Cells
  • Cricetinae
  • DNA, Complementary / genetics
  • DNA, Complementary / metabolism
  • Dogs
  • HeLa Cells
  • Humans
  • Hydrogen-Ion Concentration
  • Oligopeptides / pharmacokinetics
  • Penicillins / pharmacology
  • Peptide Transporter 1
  • Sensitivity and Specificity
  • Symporters*
  • Transfection


  • Carrier Proteins
  • Cephalosporins
  • DNA, Complementary
  • Oligopeptides
  • Penicillins
  • Peptide Transporter 1
  • SLC15A1 protein, human
  • Symporters
  • Ampicillin
  • Cephalexin