title: No evidence for circulating mesenchymal stem cells in patients with organ injury.
abstract: Mesenchymal stem cells (MSC) are present in the bone marrow, from where they are thought to migrate through the blood stream to the sites of injury. However, virtually all tissues contain resident MSC that may contribute to local regenerative and immunomodulatory processes, thereby hypothetically preempting the need for recruiting MSC through the bloodstream. Although there is some indication for circulating MSC in animal models, there is little solid evidence for the mobilization and migration of MSC in the human circulation. In the present study, we were unable to detect MSC in the blood of healthy individuals. We then searched for MSC in the blood of ten patients with end-stage renal disease, ten patients with end-stage liver disease, and in eight heart transplant patients with biopsy-proven rejection by culturing of mononuclear cells under MSC-supporting culture conditions. In none of these patient categories, MSC were identified in the blood. MSC were, however, found in the blood of a severe trauma patient with multiple fractures, suggesting that disruption of bone marrow leads to the release of MSC into the blood stream. The conclusion of this study is that MSC are not recruited into the circulation in patients with injured solid organs and during aggressive immune responses after transplantation.
authors.affiliation: 1 Nephrology and Transplantation, Department of Internal Medicine , Erasmus MC, Rotterdam, The Netherlands .
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Hoogduijn
authors.forename: Monique M A
authors.initials: MM
authors.lastname: Verstegen
authors.forename: Anja U
authors.initials: AU
authors.lastname: Engela
authors.forename: Sander S
authors.initials: SS
authors.lastname: Korevaar
authors.forename: Marieke
authors.initials: M
authors.lastname: Roemeling-van Rhijn
authors.forename: Ana
authors.initials: A
authors.lastname: Merino
authors.forename: Marcella
authors.initials: M
authors.lastname: Franquesa
authors.forename: Jeroen
authors.initials: J
authors.lastname: de Jonge
authors.forename: Jan N
authors.initials: JN
authors.lastname: Ijzermans
authors.forename: Willem
authors.initials: W
authors.lastname: Weimar
authors.forename: Michiel G H
authors.initials: MG
authors.lastname: Betjes
authors.forename: Carla C
authors.initials: CC
authors.lastname: Baan
authors.forename: Luc J W
authors.initials: LJ
authors.lastname: van der Laan
mesh_terms: D001853:Bone Marrow / Q000378:metabolism; D002454:Cell Differentiation / Q000502:physiology; D002465:Cell Movement; D050723:Fractures, Bone / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007962:Leukocytes / Q000166:cytology; D059630:Mesenchymal Stem Cells / Q000166:cytology*