title: No immune responses by the expression of the yeast Ndi1 protein in rats.
abstract: BACKGROUND
  The rotenone-insensitive internal NADH-quinone oxidoreductase from yeast, Ndi1, has been shown to work as a replacement molecule for complex I in the respiratory chain of mammalian mitochondria. In the so-called transkingdom gene therapy, one major concern is the fact that the yeast protein is foreign in mammals. Long term expression of Ndi1 observed in rodents with no apparent damage to the target tissue was indicative of no action by the host's immune system.
  
  
  RESULTS
  In the present study, we examined rat skeletal muscles expressing Ndi1 for possible signs of inflammatory or immune response. In parallel, we carried out delivery of the GFP gene using the same viral vector that was used for the NDI1 gene. The tissues were subjected to H&E staining and immunohistochemical analyses using antibodies specific for markers, CD11b, CD3, CD4, and CD8. The data showed no detectable signs of an immune response with the tissues expressing Ndi1. In contrast, mild but distinctive positive reactions were observed in the tissues expressing GFP. This clear difference most likely comes from the difference in the location of the expressed protein. Ndi1 was localized to the mitochondria whereas GFP was in the cytosol.
  
  
  CONCLUSIONS
  We demonstrated that Ndi1 expression did not trigger any inflammatory or immune response in rats. These results push forward the Ndi1-based molecular therapy and also expand the possibility of using foreign proteins that are directed to subcellular organelle such as mitochondria.
authors: Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California, United States of America.
authors: Mathieu
authors: M
authors: Marella
authors: Byoung Boo
authors: BB
authors: Seo
authors: Terence R
authors: TR
authors: Flotte
authors: Akemi
authors: A
authors: Matsuno-Yagi
authors: Takao
authors: T
authors: Yagi
mesh_terms: D000818:Animals; D000908:Antibodies, Fungal / Q000097:blood; D001921:Brain / Q000276:immunology / Q000473:pathology; D016923:Cell Death; D042967:Electron Transport Complex I / Q000276:immunology*; D007109:Immunity / Q000276:immunology*; D056724:Immunity, Humoral / Q000276:immunology; D007249:Inflammation / Q000097:blood / Q000276:immunology / Q000473:pathology; D008264:Macrophages / Q000473:pathology; D008297:Male; D009132:Muscles / Q000276:immunology / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012441:Saccharomyces cerevisiae / Q000276:immunology*; D029701:Saccharomyces cerevisiae Proteins / Q000276:immunology*; D013194:Staining and Labeling
chemical_list: D000908:Antibodies, Fungal; C493237:Ndi1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D042967:Electron Transport Complex I