title: Downregulation of CXCR4 gene expression in primary human endothelial cells following infection with E1(-)E4(+) adenovirus gene transfer vectors.
abstract: Infection of human endothelial cells with first-generation E1(-)E4(+) adenovirus (Ad) vectors leads to prolonged cell survival and changes in the cell phenotype to a more quiescent stage. Based on the concept that the CXCR4, the receptor for the endothelial chemoattractant stromal-derived factor-&alpha (SDF-alpha), is constitutively expressed by quiescent, resting endothelial cells, the present study analyzes the effect of Ad vector infection on CXCR4 expression and SDF-alpha responses of human umbilical vein endothelial cells (HUVEC). CXCR4 transcripts were markedly downregulated in E1(-)E4(+) Ad-infected cells 48 h following infection, but not in uninfected control cells or when the cells were infected with an E1(-)E4(-) Ad vector. Analysis of surface CXCR4 expression by flow cytometry demonstrated marked reduction of the CXCR4 receptor on cells infected with E1(-)E4(+) Ad compared to uninfected control cells or E1(-)E4(-) Ad-infected cells. Infection of other cell types which express CXCR4, such as dendritic cells and myeloma cells, did not exhibit CXCR4 receptor downregulation following infection with E1(-)E4(+) Ad. Consistent with the observed downregulation of CXCR4 mRNA and surface protein, infection of the endothelial cells with an E1(-)E4(+) Ad rendered the cells unresponsive to the chemoattractant SDF-alpha compared to naive or E1(-)E4(-) Ad-infected cells. Together, the data suggest that first-generation Ad vectors, likely the E4 region, modify the ability of endothelial cells to respond to at least one important chemoattractant.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Weill Medical College of Cornell University-New York Presbyterian Hospital, New York, New York 94143, USA.
authors.forename: R
authors.initials: R
authors.lastname: Ramalingam
authors.forename: S
authors.initials: S
authors.lastname: Worgall
authors.forename: S
authors.initials: S
authors.lastname: Rafii
authors.forename: R G
authors.initials: RG
authors.lastname: Crystal
mesh_terms: D000256:Adenoviridae / Q000235:genetics*; D017498:Adenovirus E1 Proteins / Q000235:genetics*; D017504:Adenovirus E4 Proteins / Q000235:genetics*; D015152:Blotting, Northern; D002478:Cells, Cultured; D015536:Down-Regulation; D004730:Endothelium, Vascular / Q000378:metabolism*; D005434:Flow Cytometry; D015870:Gene Expression; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D005822:Genetic Vectors; D006801:Humans; D009389:Neovascularization, Pathologic / Q000628:therapy; D012333:RNA, Messenger / Q000378:metabolism*; D019718:Receptors, CXCR4 / Q000235:genetics* / Q000378:metabolism; D014162:Transfection; D001616:beta-Galactosidase / Q000378:metabolism
chemical_list: D017498:Adenovirus E1 Proteins; D017504:Adenovirus E4 Proteins; D012333:RNA, Messenger; D019718:Receptors, CXCR4; D001616:beta-Galactosidase