title: Inhibition of nuclear delivery of plasmid DNA and transcription by interferon γ: hurdles to be overcome for sustained gene therapy.
abstract: Sustained expression of murine interferon (IFN)-γ (Muγ) was found to be effective in preventing tumor metastasis and atopic dermatitis in mouse models. However, our preliminary experiments suggested that the time-dependent decrease in the Muγ expression was not compensated for by repeated injections of Muγ-expressing plasmid. To identify the mechanism underlying this observation, a reporter plasmid was hydrodynamically injected into mice and the levels of the plasmid, mRNA and reporter protein were measured in mice receiving a pre- or co-administration of Muγ-expressing plasmid. Co-injection of Muγ-expressing plasmid had no significant effects on transgene expression from the reporter plasmid. In contrast, pre-injection of Muγ-expressing plasmid greatly inhibited the expression of the reporter protein. Moreover, pre-injection of Muγ-expressing plasmid also reduced the amount of the reporter plasmid in the nuclear fraction of mouse liver to < 10%, and that of reporter mRNA to < 1%. The degree of reduction in the expression of reporter protein was comparable with the reduction in mRNA. These results indicate that the difficulty in regaining the expression level of IFN-γ is due to the impaired delivery of plasmid to the nucleus and to the suppression of transcription from the plasmid.
authors: Department of Biopharmaceutics and Drug Metabolism, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto, Japan.
authors: L
authors: L
authors: Zang
authors: M
authors: M
authors: Nishikawa
authors: K
authors: K
authors: Machida
authors: M
authors: M
authors: Ando
authors: Y
authors: Y
authors: Takahashi
authors: Y
authors: Y
authors: Watanabe
authors: Y
authors: Y
authors: Takakura
mesh_terms: D000818:Animals; D002467:Cell Nucleus / Q000235:genetics*; D002478:Cells, Cultured; D015870:Gene Expression; D018014:Gene Transfer Techniques; D057446:Hydrodynamics; D007273:Injections, Intramuscular; D007371:Interferon-gamma / Q000097:blood / Q000235:genetics*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D010957:Plasmids; D012333:RNA, Messenger / Q000378:metabolism; D019076:Transgenes
chemical_list: D012333:RNA, Messenger; D007371:Interferon-gamma