title: Hepatocyte growth factor/c-MET axis-mediated tropism of cord blood-derived unrestricted somatic stem cells for neuronal injury.
abstract: An under-agarose chemotaxis assay was used to investigate whether unrestricted somatic stem cells (USSC) that were recently characterized in human cord blood are attracted by neuronal injury in vitro. USSC migrated toward extracts of post-ischemic brain tissue of mice in which stroke had been induced. Moreover, apoptotic neurons secrete factors that strongly attracted USSC, whereas necrotic and healthy neurons did not. Investigating the expression of growth factors and chemokines in lesioned brain tissue and neurons and of their respective receptors in USSC revealed expression of hepatocyte growth factor (HGF) in post-ischemic brain and in apoptotic but not in necrotic neurons and of the HGF receptor c-MET in USSC. Neuronal lesion-triggered migration was observed in vitro and in vivo only when c-MET was expressed at a high level in USSC. Neutralization of the bioactivity of HGF with an antibody inhibited migration of USSC toward neuronal injury. This, together with the finding that human recombinant HGF attracts USSC, document that HGF signaling is necessary for the tropism of USSC for neuronal injury. Our data demonstrate that USSC have the capacity to migrate toward apoptotic neurons and injured brain. Together with their neural differentiation potential, this suggests a neuroregenerative potential of USSC. Moreover, we provide evidence for a hitherto unrecognized pivotal role of the HGF/c-MET axis in guiding stem cells toward brain injury, which may partly account for the capability of HGF to improve function in the diseased central nervous system.
authors.affiliation: Institute for Transplantation Diagnostics and Cell Therapeutics, Heinrich-Heine-University Medical Center, D-40225 Düsseldorf, Germany. trapp@itz.uni-duesseldorf.de
authors.forename: Thorsten
authors.initials: T
authors.lastname: Trapp
authors.forename: Gesine
authors.initials: G
authors.lastname: Kögler
authors.forename: Abdelouahid
authors.initials: A
authors.lastname: El-Khattouti
authors.forename: Rüdiger V
authors.initials: RV
authors.lastname: Sorg
authors.forename: Michael
authors.initials: M
authors.lastname: Besselmann
authors.forename: Melanie
authors.initials: M
authors.lastname: Föcking
authors.forename: Christian P
authors.initials: CP
authors.lastname: Bührle
authors.forename: Ingo
authors.initials: I
authors.lastname: Trompeter
authors.forename: Johannes C
authors.initials: JC
authors.lastname: Fischer
authors.forename: Peter
authors.initials: P
authors.lastname: Wernet
mesh_terms: D000818:Animals; D017209:Apoptosis; D001921:Brain / Q000378:metabolism; D002545:Brain Ischemia / Q000473:pathology; D002465:Cell Movement; D005312:Fetal Blood / Q000378:metabolism*; D017228:Hepatocyte Growth Factor / Q000378:metabolism*; D006801:Humans; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008954:Models, Biological; D009474:Neurons / Q000378:metabolism*; D019859:Proto-Oncogene Proteins c-met / Q000378:metabolism*; D013234:Stem Cells / Q000166:cytology*
chemical_list: D017228:Hepatocyte Growth Factor; D019859:Proto-Oncogene Proteins c-met