Regulation of expression and function of dipeptidyl peptidase 4 (DP4), DP8/9, and DP10 in allergic responses of the lung in rats

J Histochem Cytochem. 2008 Feb;56(2):147-55. doi: 10.1369/jhc.7A7319.2007. Epub 2007 Oct 29.


The expression of dipeptidyl peptidase 4 (DP4, CD26) affects T-cell recruitment to lungs in an experimental rat asthma model. Furthermore, the gene of the structural homologous DP10 represents a susceptibility locus for asthma in humans, and the functional homologous DP8/9 are expressed in human leukocytes. Thus, although several mechanisms may account for a role of DP4-like peptidases in asthma, detailed information on their anatomical sites of expression and function in lungs is lacking. Therefore, bronchi and lung parenchyma were evaluated using immunohistochemistry and histochemical/enzymatic activity assays, as well as quantitative real-time PCR for this family of peptidases in naïve and asthmatic rat lungs derived from wild-type F344 and DP4-deficient F344 rat strains. Surprisingly, results show not only that the induction of experimental asthma increases DP4 enzymatic activity in the bronchoalveolar lavage fluid and parenchyma, but also that DP8/9 enzymatic activity is regulated and, as well as the expression of DP10, primarily found in the bronchial epithelium of the airways. This is the first report showing a differential and site-specific DP4-like expression and function in the lungs, suggesting a pathophysiologically significant role in asthma.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Asthma / enzymology*
  • Bronchi / enzymology
  • Dipeptidyl Peptidase 4 / biosynthesis
  • Dipeptidyl Peptidase 4 / genetics
  • Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / biosynthesis*
  • Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / genetics
  • Gene Expression Regulation, Enzymologic
  • Immunohistochemistry
  • Lung / enzymology*
  • Male
  • Polymerase Chain Reaction
  • Rats
  • Rats, Inbred F344


  • DPP10 protein, rat
  • Dipeptidyl-Peptidases and Tripeptidyl-Peptidases
  • Dpp8 protein, rat
  • Dpp9 protein, rat
  • Dipeptidyl Peptidase 4