title: Expression of CXCR4 in cord blood-derived CD133+ cells treated with platelet micro-particles.
abstract: Platelet micro-particles (MPs) contain CXCR4 markers and are able to transfer them into hematopoietic stem cells. Therefore, effect of platelet MPs (PMPs) on the expression levels of CXCR4 and CD34 markers in these cells was examined. Isolated CD 133+ cells cultivated for 5 d in the stem span medium and PMPs. Fold increase of CD34+ cells in the presence of 5 and 10 g/ml of PMPs was increased significantly. CXCR4+ cell percent in the presence of 10 g/ml PMPs compared with control cells (63.8 ± 6.4) was increased (P < 0.05). PMPs were no affect on clonogenicity of hematopoietic progenitor cells.
  
  
  BACKGROUND
  Cord blood CD133+ cells are able to maintain long-term hematopoiesis and to differentiate to hematopoietic lineages. CXCR4 over expression is involved in homing and successful transplantation of hematopoietic stem cells (HSCs) in the bone marrow. PMPs contain CXCR4 markers and are able to transfer them into hematopoietic stem cells. Therefore, considering the importance of CD133+ cells as primitive HSCs, the effect of PMPs on the expression levels of CXCR4 and CD34 markers in these cells was examined.
  
  
  METHODS
  Cord blood CD133+ cells were isolated by MACS. Isolated cells were divided into three groups: (i) control cells, (ii) cells treated with 5 μg/ml PMPs, (iii) cells treated with 10 μg/ml PMPs. Cells were cultivated for 5 d in the stem span medium. Expression of CD 133, CD34, and CXCR4 surface marker was analyzed by flow cytometry. Total cell numbers were counted by hemocytometer and clonogenicity were measured by colony assay.
  
  
  RESULTS
  PMPs were no effect on CD133+ cells proliferation, but fold increase of CD34+ cells in the presence of 5 and 10 g/ml of PMPs was increased significantly. CXCR4+ cell percent in the presence of 10 g/ml PMPs compared with control cells (63.8 ± 6.4) was increased (P < 0.05). PMPs were no affect on clonogenicity of hematopoietic progenitor cells.
  
  
  CONCLUSIONS
  Exposure of CD133+ cells isolated from cord blood to PMPs with 10 μg/ml concentration increased the expression of CXCR4 surface marker significantly.
authors.affiliation: a Blood Transfusion Research Center, High Institute for Education and Research in Transfusion Medicine , Tehran , The Islamic Republic of Iran.
authors.forename: Farzaneh
authors.initials: F
authors.lastname: Moghaddam
authors.affiliation: a Blood Transfusion Research Center, High Institute for Education and Research in Transfusion Medicine , Tehran , The Islamic Republic of Iran.
authors.forename: Arezoo
authors.initials: A
authors.lastname: Oodi
authors.affiliation: a Blood Transfusion Research Center, High Institute for Education and Research in Transfusion Medicine , Tehran , The Islamic Republic of Iran.
authors.forename: Mahin
authors.initials: M
authors.lastname: Nikougoftar Zarif
authors.affiliation: a Blood Transfusion Research Center, High Institute for Education and Research in Transfusion Medicine , Tehran , The Islamic Republic of Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Amani
authors.affiliation: a Blood Transfusion Research Center, High Institute for Education and Research in Transfusion Medicine , Tehran , The Islamic Republic of Iran.
authors.forename: Naser
authors.initials: N
authors.lastname: Amirizadeh
mesh_terms: D000071916:AC133 Antigen / Q000378:metabolism*; D001792:Blood Platelets / Q000737:chemistry*; D055252:Cell-Derived Microparticles / Q000737:chemistry*; D005260:Female; D005312:Fetal Blood / Q000166:cytology / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D008297:Male; D019718:Receptors, CXCR4 / Q000096:biosynthesis*
chemical_list: D000071916:AC133 Antigen; C527276:CXCR4 protein, human; C000606023:PROM1 protein, human; D019718:Receptors, CXCR4
keywords: CD133 antigen; CXCR4 receptor; platelet micro-particles; stem cell