Incorporation of Tumor Vasculature Targeting Motifs into Moloney Murine Leukemia Virus Env Escort Proteins Enhances Retrovirus Binding and Transduction of Human Endothelial Cells
AUTOR(ES)
Liu, Liqiong
FONTE
American Society for Microbiology
RESUMO
Adhesion receptors expressed on the surfaces of tumor-activated endothelial cells provide an advantageous locus for targeting gene therapy vectors to angiogenic tissues and/or tumor vasculature. In this study, we engineered a series of Asn-Gly-Arg (NGR)-containing congeners of the presumptive cell binding motif contained within the ninth type III repeat of fibronectin and displayed these tumor vasculature targeting motifs (TVTMs) within the context of Moloney murine leukemia envelope “escort” proteins. Comparative studies of envelope incorporation into viral particles and evaluation of the cell binding properties of the targeted vectors revealed critical structural features, thus identifying a subset of optimal TVTMs. Utilizing a modified ELISA to evaluate viral binding to target cells, we observed a significant down-regulation of TVTM-virion binding to human endothelial cells following sustained (48-h) exposure to VEGF. Normalized for equivalent titers (106 CFU/ml), as assayed on NIH 3T3 cells, vectors displaying TVTM escort proteins significantly enhanced the transduction efficiency from 12.2 to 37.4% in human KSY-1 endothelial cell cultures (P < 0.001) and from 0.4 to 4.1% in human umbilical vein endothelial cell (HUVEC) cultures (P < 0.001). In summary, these studies utilized an engineering approach to identify a subset of TVTMs that are stably incorporated as envelope “escort” proteins into retroviral vectors and that, by functioning to improve the binding efficiency and transduction of both HUVEC and KSY1 endothelial cells, may have therapeutic potential for targeting gene delivery to the tumor-associated vasculature.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=110887Documentos Relacionados
- Incorporation of homologous and heterologous proteins into the envelope of Moloney murine leukemia virus.
- Transport and assembly of gag proteins into Moloney murine leukemia virus.
- Incorporation of human immunodeficiency virus type 1 Gag proteins into murine leukemia virus virions.
- Targeting tumor vasculature endothelial cells and tumor cells for immunotherapy of human melanoma in a mouse xenograft model
- Binding kinetics of ecotropic (Moloney) murine leukemia retrovirus with NIH 3T3 cells.