title: Sustained expression of Fc-fusion cytokine following in vivo electroporation and mouse strain differences in expression levels.
abstract: We previously demonstrated that cytokine expression following intramuscular gene transfer of a naked plasmid is increased 2 logs by in vivo electroporation, but the relatively low expression levels of the encoded protein is still a limitation for successful gene therapy and gene function studies. We recently reported that the serum viral IL-10 levels achieved by electroporation-mediated intramuscular delivery of pCAGGS-vIL10, a viral IL-10-expressing plasmid, can be further enhanced by modifying the plasmid into an immunoglobulin fusion protein expression plasmid, pCAGGS-vIL10/Fc. Here we examined the applicability of this approach to the expression of an endogenous cytokine, IL-10, in two different inbred mouse strains. We obtained sustained high serum levels of IL-10 in C3H/HeJ mice (C3H), but the level and duration of the gene expression was mouse-strain dependent. Although the serum IL-10 level was also increased by using the IL-10/Fc gene plasmid in C57BL/6 mice (B6), IL-10/Fc and a luciferase reporter showed significantly lower levels in B6 than in C3H mice, and the persistence of pCAGGS-IL10/Fc expression ranged from several days in B6 mice to more than one month in C3H mice. These results suggest that the electroporation-mediated intramuscular delivery of the immunoglobulin fusion protein expression plasmid is simple and very efficient, but mouse strain differences in transgene expression should be taken into consideration in its use.
authors.affiliation: Division of Stem Cell Regulation Research (G6), Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka 565-0871.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Jiang
authors.forename: Eiji
authors.initials: E
authors.lastname: Yamato
authors.forename: Jun-ichi
authors.initials: J
authors.lastname: Miyazaki
mesh_terms: D000818:Animals; D016207:Cytokines / Q000096:biosynthesis* / Q000235:genetics; D018274:Electroporation; D015870:Gene Expression; D018014:Gene Transfer Techniques; D007141:Immunoglobulin Fc Fragments / Q000096:biosynthesis* / Q000235:genetics; D016753:Interleukin-10 / Q000096:biosynthesis* / Q000097:blood / Q000235:genetics; D008156:Luciferases / Q000032:analysis / Q000235:genetics; D051379:Mice; D008809:Mice, Inbred C3H; D008810:Mice, Inbred C57BL; D010957:Plasmids; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis; D013045:Species Specificity
chemical_list: D016207:Cytokines; D007141:Immunoglobulin Fc Fragments; D011993:Recombinant Fusion Proteins; D016753:Interleukin-10; D008156:Luciferases