Year: 2006
Type: article
Abstract: A versatile, potent technique for imaging cells in culture and in vivo has been achieved by expressing a metabolically biotinylated reporter protein on the cell surface and visualizing this transgene product with labeled streptavidin moieties. The recombinant reporter protein incorporates the prokaryotic Propionibacterium shermanii 1.3S transcarboxylase domain biotin acceptor peptide (BAP) between an N-terminal signal sequence and the PDGF receptor transmembrane domain (TM,Fig. 1). Western blot analysis of cell homogenates, immunocytochemistry of non-permeablized cells and FACS analysis demonstrated that this BAP-TM reporter protein is efficiently biotinylated by endogenous biotin ligase in mammalian cells with the biotin displayed on the cell surface. Magnetic resonance and fluorescence tomographic imaging in vivo showed significant decrease in the spin-spin relaxation time T2 and over 15-fold increase in fluorescence in BAP-TM-reporter-expressing tumors as compared to control tumors following intravascular injection of streptavidin- magnetic nanoparticles or streptavidin-Alexa680 conjugates, respectively. This reporter proved to be more efficient for magnetic resonance imaging than an engineered transferrin receptor reporter previously developed in our laboratory. Moreover, intravascular injection of streptavidin-horseradish peroxidase conjugates, in conjunction with a gadolinium-based magnetic resonance agent sensitive to peroxidase activity, selectively enhanced BAP-TM- reporter expressing tumors. This BAP-TM reporter allows for non- invasive real time imaging of any cell type transduced to express it in culture or in vivo, and should be compatible with use in humans since streptavidin-biotin system and paramagnetic nanoparticles are being used in clinical trials.
Source: Molecular Therapy
Authors: Bakhos A. Tannous, Jan Grimm, Katherine F. Perry, John W. Chen, Weissleder Ralph, Breakefield O. Xandra
Institutions: Harvard University, Massachusetts General Hospital
Language: English
Topic: Biotin and Related Studies
Subfield: Cell Biology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $4,500
OpenAlex ID: W1964218404