title: CXCR4 transfection of cord blood mesenchymal stromal cells with the use of cationic liposome enhances their migration toward stromal cell-derived factor-1.
abstract: OBJECTIVE
  The interaction between stromal cell-derived factor (SDF)-1 and its receptor CXCR4 is one of the mechanisms by which mesenchymal stromal cells (MSCs) are recruited to sites of injury. SDF-1 is upregulated in damaged tissues, but because the surface expression of CXCR4 on cultured MSCs is low, we investigated whether the delivery of CXCR4 into MSCs with the use of the cationic liposomal reagent IBAfect would increase their migration toward SDF-1.
  
  
  METHODS
  We examined (i) the effect of MSC confluency, passage number, duration of transfection and amount of IBAfect and plasmid on transfection efficiency as determined by flow cytometric analysis of CXCR4 and (ii) whether IBAfect-mediated CXCR4 transfection affected the viability, proliferation and differentiation of MSCs as well as their response toward an SDF-1 gradient in a trans-Matrigel migration assay.
  
  
  RESULTS
  We found that transfection efficiency of up to 40% was achieved after 24-h transfection of 50% confluent MSCs (at passage 4) with an IBAfect:plasmid ratio of 3.6 μL:0.6 μg, and CXCR4 transcript expression in transfected MSCs was 10(5)-fold higher than in non-transfected cells. Transfected MSCs retained their ability to differentiate to osteocytes and chondrocytes but had lower proliferation. Importantly, overexpression of surface CXCR4 with the use of IBAfect significantly increased (>3-fold) the number of cells migrating toward an SDF-1 gradient relative to cells migrating to media alone, compared with non-transfected cells (1.3-fold).
  
  
  CONCLUSIONS
  Our results suggest that IBAfect-mediated delivery of CXCR4 into MSCs is a highly efficient technique that may be useful for enhancing the recruitment of systemically infused MSCs for tissue repair.
authors.affiliation: Canadian Blood Services R&D, Edmonton, Alberta, Canada.
authors.forename: Leah A
authors.initials: LA
authors.lastname: Marquez-Curtis
authors.forename: Hilal
authors.initials: H
authors.lastname: Gul-Uludag
authors.forename: Peng
authors.initials: P
authors.lastname: Xu
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
authors.forename: Anna
authors.initials: A
authors.lastname: Janowska-Wieczorek
mesh_terms: D002454:Cell Differentiation / Q000235:genetics; D002465:Cell Movement / Q000235:genetics; D002478:Cells, Cultured; D054377:Chemokine CXCL12 / Q000235:genetics / Q000378:metabolism*; D019902:Chondrocytes / Q000166:cytology; D005312:Fetal Blood / Q000166:cytology* / Q000378:metabolism; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000378:metabolism; D008081:Liposomes / Q000008:administration & dosage / Q000737:chemistry; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000378:metabolism; D010011:Osteocytes / Q000166:cytology; D019718:Receptors, CXCR4 / Q000008:administration & dosage / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D014947:Wounds and Injuries / Q000378:metabolism / Q000473:pathology
chemical_list: C527276:CXCR4 protein, human; D054377:Chemokine CXCL12; D008081:Liposomes; D019718:Receptors, CXCR4