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Andrew Price

Publications and source records attributed to Andrew Price.

3 recordsLinked to original sources
PubMed2004

In vivo imaging of graft-versus-host-disease in mice.

We have developed a mouse system by which to track the migration and homing of cells in a setting of bone marrow transplantation (BMT)-induced graft-versus-host disease (GVHD) after systemic infusion using enhanced green fluorescence protein (eGFP) transgenic (Tg) cells and a simple application of a fluorescence stereomicroscope outfitted with a color charge-coupled device (CCD) camera. Whole body images of anesthetized mice taken at various time points after cell infusion revealed the early migration of allogeneic cells to peripheral lymphoid organs, with later infiltration of GVHD target organs. Localization of eGFP Tg cells could be seen through the skin of shaved mice, and internal organs were easily discernible. After allogeneic or syngeneic eGFP Tg cell infusion, representative mice were dissected to better visualize deeper internal organs and tissues. Infusion of different cell populations revealed distinct homing patterns, and this method also provided a simple way to identify the critical time points for expansion of the transplanted cells in various organs. This simple application of the fluorescence stereomicroscope will be valuable for GVHD and graft-versus-tumor studies in which visualization of cellular migration, expansion, and cell-cell interactions will be more informative when analyzed by such an intravital method.

Animals↗
PubMed2004

A generic sandwich-type biosensor with nanomolar detection limits.

A quantitative and highly sensitive, yet simple and rapid, biosensor system was developed for the detection of nucleic acid sequences that can also be adapted to the detection of antigens. A dipstick-type biosensor with liposome amplification, based on a sandwich assay format with optical detection, was combined with a simple coupling reaction that allows the transformation of the generic biosensor components to target specific ones by a mere incubation step. This biosensor platform system was developed and optimized, and its principle was proven using DNA oligonucleotides that provided a nucleic acid biosensor for the specific detection of RNA and DNA sequences. However, the coupling reaction principle chosen can also be used for the immobilization of antibodies or receptor molecules, and therefore for the development of immunosensors and receptor-based biosensors. The generic biosensor consists of liposomes entrapping sulforhodamine B that are coated with streptavidin on the outside, and polyethersulfone membranes with anti-fluorescein antibodies immobilized in the detection zone. In order to transform the generic biosensor into a specific DNA/RNA biosensor, two oligonucleotides that are able to hybridize to the target sequence were labeled with a biotin and a fluorescein molecule, respectively. By simultaneously incubating the liposomes, both oligonucleotides, and the target sequence in a hybridization buffer for 20-30 min at 42 degrees C, a sandwich complex was formed. The mixture was applied to the polyethersulfone membrane. The complex was captured in the detection zone and quantified using a hand-held reflectometer. The system was tested using RNA sequences from B. anthracis, C. parvum and E. coli. Quantitation of concentrations between 10 fmol and 1000 fmol (10-1000 nM) was possible without altering any biosensor assay conditions. In addition, no changes to hybridization conditions were required when using authentic nucleic acid sequence-based amplified RNA sequences, and the generic biosensor compared favorably with those previously developed specifically for the RNA sequences. Therefore, the universal biosensor described is an excellent tool, for use in laboratories or at test sites, for rapidly investigating and quantifying any nucleic acid sequence of interest, as well as potentially any antigen of interest that can be bound by two antibodies simultaneously.

Animals↗