title: Expression pattern of CD2 locus control region containing retroviral vectors in hemopoietic cells in vitro and in vivo.
abstract: We introduced the locus control region (LCR) of the human CD2 gene in eight different ways into retroviral constructs containing the human adenosine deaminase (hADA) gene. Two of these constructs were tested in transgenic mice. Neither expressed hADA in any examined tissue, nor did control vectors without the LCR insert. Amphotropic retrovirus vector producer cell clones were isolated and analyzed for provirus integrity and vector titer. Three constructs yielded recombined proviruses in 20-100% of transduced clones, whereas the other five constructs always rendered viruses that remained stable upon replication and gave vector titers comparable to the control lacking an LCR. Human ADA-deficient T cells and murine fibroblasts transduced with these recombinant viruses showed considerable hADA expression levels that were, however, not significantly different from those of cells transduced with the control vector lacking an LCR insert. Furthermore, no difference in hADA expression levels could be detected in spleen, thymus and bone marrow of long-term repopulated mice that had received bone marrow cells transduced with either the control vector or one of two different CD2-LCR containing vectors. In conclusion, the CD2-LCR does not alleviate the expression block for recombinant retroviruses in the germ line and does not enhance the LTR-driven expression in T cells.
authors.affiliation: Department of Molecular Cell Biology, University of Leiden, The Netherlands.
authors.forename: L C
authors.initials: LC
authors.lastname: Kaptein
authors.forename: M
authors.initials: M
authors.lastname: Breuer
authors.forename: D
authors.initials: D
authors.lastname: Valerio
authors.forename: V W
authors.initials: VW
authors.lastname: van Beusechem
mesh_terms: D000243:Adenosine Deaminase / Q000235:genetics / Q000378:metabolism; D000818:Animals; D015139:Blotting, Southern; D016026:Bone Marrow Transplantation; D018801:CD2 Antigens / Q000235:genetics*; D018929:Cell Culture Techniques; D005347:Fibroblasts / Q000201:enzymology; D015870:Gene Expression; D005822:Genetic Vectors; D006801:Humans; D019901:Locus Control Region; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D008822:Mice, Transgenic; D012190:Retroviridae / Q000235:genetics*; D013601:T-Lymphocytes / Q000201:enzymology*
chemical_list: D018801:CD2 Antigens; D000243:Adenosine Deaminase