DPP9 enzymatic activity in hematopoietic cells is dispensable for mouse hematopoiesis

Immunol Lett. 2018 Jun:198:60-65. doi: 10.1016/j.imlet.2018.04.008. Epub 2018 Apr 27.

Abstract

Dipeptidyl peptidase 9 (DPP9) is a ubiquitously expressed intracellular prolyl peptidase implicated in immunoregulation. However, its physiological relevance in the immune system remains largely unknown. We investigated the role of DPP9 enzyme in immune system by characterizing DPP9 knock-in mice expressing a catalytically inactive S729A mutant of DPP9 enzyme (DPP9ki/ki mice). DPP9ki/ki mice show reduced number of lymphoid and myeloid cells in fetal liver and postnatal blood but their hematopoietic cells are fully functional and able to reconstitute lymphoid and myeloid lineages even in competitive mixed chimeras. These studies demonstrate that inactivation of DPP9 enzymatic activity does not lead to any perturbations in mouse hematopoiesis.

Keywords: Competitive reconstitution assay; DPP9; DPP9 knock-in enzyme inactive mice; Dipeptidyl peptidase; Hematopoiesis; Hematopoietic stem cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Count
  • Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / genetics
  • Dipeptidyl-Peptidases and Tripeptidyl-Peptidases / metabolism*
  • Gene Knock-In Techniques
  • Hematopoiesis / immunology*
  • Hematopoietic Stem Cells / cytology
  • Hematopoietic Stem Cells / physiology*
  • Lymphocytes / cytology
  • Myeloid Cells / cytology

Substances

  • Dipeptidyl-Peptidases and Tripeptidyl-Peptidases
  • dipeptidyl peptidase 9, mouse