By a News Reporter-Staff News Editor at Gene Therapy Weekly -- A new study on Proteins is now available. According to news reporting originating from Charlottesville, Virginia, by NewsRx correspondents, research stated, "AAV9 is a powerful gene delivery vehicle capable of providing long-term gene expression in a variety of cell types, particularly cardiomyocytes. The use of AAV-delivery for RNA interference is an intense area of research, but a comprehensive analysis of knockdown in cardiac and liver tissues after systemic delivery of AAV9 has yet to be reported."
Our news editors obtained a quote from the research from the University of Virginia, "We sought to address this question by using AAV9 to deliver a short-hairpin RNA targeting the enhanced green fluorescent protein (GFP) in transgenic mice that constitutively overexpress GFP in all tissues. The expression cassette was initially tested in vitro and we demonstrated a 61% reduction in mRNA and a 90% reduction in GFP protein in dual-transfected 293 cells. Next, the expression cassette was packaged as single-stranded genomes in AAV9 capsids to test cardiac GFP knockdown with several doses ranging from 1.8 x 10(10) to 1.8 x 10(11) viral genomes per mouse and a dose-dependent response was obtained. We then analyzed GFP expression in both heart and liver after delivery of 4.4 x 10(11) viral genomes per mouse. We found that while cardiac knockdown was highly efficient, with a 77% reduction in GFP mRNA and a 71% reduction in protein versus control-treated mice, there was no change in liver expression. This was despite a 4.5-fold greater number of viral genomes in the liver than in the heart."
According to the news editors, the research concluded: "This study demonstrates that single-stranded AAV9 vectors expressing shRNA can be used to achieve highly efficient cardiac-selective knockdown of GFP expression that is sustained for at least 7 weeks after the systemic injection of 8 day old mice, with no change in liver expression and no evidence of liver damage despite high viral genome presence in the liver."
For more information on this research see: Systemic delivery of shRNA by AAV9 provides highly efficient knockdown of ubiquitously expressed GFP in mouse heart, but not liver. Plos One, 2013;8(9):e75894. (Public Library of Science - www.plos.org; Plos One - www.plosone.org)
The news editors report that additional information may be obtained by contacting B.A. Piras, Dept. of Biomedical Engineering, University of Virginia, Charlottesville, Virginia, United States. Additional authors for this research include D.M. O'Connor and B.A French (see also Proteins).
Keywords for this news article include: Biotechnology, Virginia, Cardiology, Gene Therapy, Viral Genome, United States, Bioengineering, Charlottesville, North and Central America, Green Fluorescent Protein.
Our reports deliver fact-based news of research and discoveries from around the world. Copyright 2014, NewsRx LLC