title: The CXCR4 antagonist AMD3100 releases a subset of G-CSF-primed peripheral blood progenitor cells with specific gene expression characteristics.
abstract: OBJECTIVE
  AMD3100 is a new CXCR4 antagonist that induces a rapid release of hematopoietic progenitors from the bone marrow to the peripheral blood. We conducted a clinical study where patients with multiple myeloma and non-Hodgkin's lymphoma were treated with AMD3100 (A) to increase the number of peripheral blood progenitor cells (PBPCs) when given a mobilization regimen of granulocyte colony-stimulating factor (G-CSF, G). Because experimental data suggest that A+G-mobilized PBPCs are functionally different from G-mobilized PBPCs, we were interested in an intraindividual comparison of the gene expression profile of CD34+ cells in the two different settings.
  
  
  METHODS
  To this end peripheral blood CD34+ cells of three patients (three G, three A+G samples) were isolated by immunomagnetic followed by flow cytometric sorting to a purity of >99%. Total RNA was purified. Differentially expressed genes were analyzed by using the Affymetrix GeneChip Human Genome U133 Plus2.0 and the software package Micro Array Solutions 1.3 (SAS Institute Inc.).
  
  
  RESULTS
  We found a pattern of unanimously higher (81 genes, log2 ratio > 0.5; p < 0.0001) or lower (29 genes, log2 ratio < -0.4; p < 0.0001) expressed genes in the A+G-mobilized vs G-mobilized CD34+ PBPCs. Significant changes of four selected genes noted in the microarray analysis were validated by quantitative real-time polymerase chain reaction. Genes were grouped according to gene function. Only increased expression was found in the categories antiapoptosis (e.g., MPO, HSPA1B), cell cycle (e.g., MS4A3, RRM2), replication/DNA repair (e.g., MPO, HSPA1B), cell motility (e.g., TNFSF4, HMMR), and oxygen transport. Decreased expression occurred in the proapoptosis gene group (e.g., MDA5, BCL10). CXCR4 receptor gene expression itself was significantly 1.5-fold higher in the A+G vs G group.
  
  
  CONCLUSIONS
  We conclude that A+G-mobilized CD34+ PBPCs express significantly higher amounts of genes that potentially promote superior engraftment after myeloablative therapy than G-mobilized CD34+ PBPCs.
authors.affiliation: Department of Internal Medicine V, University of Heidelberg, Heidelberg, Germany. Stefan.Fruehauf@med.uni-heidelberg.de
authors.forename: Stefan
authors.initials: S
authors.lastname: Fruehauf
authors.forename: Timon
authors.initials: T
authors.lastname: Seeger
authors.forename: Patrick
authors.initials: P
authors.lastname: Maier
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.forename: Stephan
authors.initials: S
authors.lastname: Weinhardt
authors.forename: Stephanie
authors.initials: S
authors.lastname: Laufs
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Wagner
authors.forename: Volker
authors.initials: V
authors.lastname: Eckstein
authors.forename: Gary
authors.initials: G
authors.lastname: Bridger
authors.forename: Gary
authors.initials: G
authors.lastname: Calandra
authors.forename: Frederick
authors.initials: F
authors.lastname: Wenz
authors.forename: W Jens
authors.initials: WJ
authors.lastname: Zeller
authors.forename: Hartmut
authors.initials: H
authors.lastname: Goldschmidt
authors.forename: Anthony D
authors.initials: AD
authors.lastname: Ho
mesh_terms: D001596:Benzylamines; D000080027:Cyclams; D020869:Gene Expression Profiling; D016179:Granulocyte Colony-Stimulating Factor / Q000494:pharmacology*; D019650:Hematopoietic Stem Cell Mobilization; D006412:Hematopoietic Stem Cells / Q000378:metabolism*; D006571:Heterocyclic Compounds / Q000494:pharmacology*; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis; D036102:Peripheral Blood Stem Cell Transplantation; D019718:Receptors, CXCR4 / Q000037:antagonists & inhibitors* / Q000502:physiology
chemical_list: D001596:Benzylamines; D000080027:Cyclams; D006571:Heterocyclic Compounds; D019718:Receptors, CXCR4; D016179:Granulocyte Colony-Stimulating Factor; C088327:plerixafor