Citation Details

Journal Article

Animals; Bioware; Diagnostic Imaging; Forecasting; Luminescent Measurements; Mice; Models, Animal; Neoplasms; PC-3M-luc; Sensitivity and Specificity

Malignant disease is the final manifestation of complex molecular and cellular events leading to uncontrolled cellular proliferation and eventually tissue destruction and metastases. While the in vitro examination of cultured tumour cells permits the molecular dissection of early pathways in tumorigenesis on cellular and subcellular levels, only interrogation of these processes within the complexity of organ systems of the living animal can reveal the full range of pathophysiological changes that occur in neoplastic disease. Such analyses require technologies that facilitate the study of biological processes in vivo, and several approaches have been developed over the last few years. These strategies, in the nascent field of in vivo molecular and cellular imaging, combine molecular biology with imaging modalities as a means to real-time acquisition of functional information about disease processes in living systems. In this review, we will summarise recent developments in in vivo bioluminescence imaging (BLI) and discuss the potential of this imaging strategy for the future of cancer research.

Journal Article

inflammation; immune response; rheumatoid arthritis; arthritis; in vivo imaging

OBJECTIVE: The NF-kappaB signaling pathway promotes the immune response in rheumatoid arthritis (RA) and in rodent models of RA. NF-kappaB activity is regulated by the IKK-2 kinase during inflammatory responses. To elucidate how IKK-2 inhibition suppresses disease development, we used a combination of in vivo imaging, transcription profiling, and histopathology technologies to study mice with antibody-induced arthritis.

METHODS: ML120B, a potent, small molecule inhibitor of IKK-2, was administered to arthritic animals, and disease activity was monitored. NF-kappaB activity in diseased joints was quantified by in vivo imaging. Quantitative reverse transcriptase-polymerase chain reaction was used to evaluate gene expression in joints. Protease-activated near-infrared fluorescence (NIRF) in vivo imaging was applied to assess the amounts of active proteases in the joints.

RESULTS: Oral administration of ML120B suppressed both clinical and histopathologic manifestations of disease. In vivo imaging demonstrated that NF-kappaB activity in inflamed arthritic paws was inhibited by ML120B, resulting in significant suppression of multiple genes in the NF-kappaB pathway, i.e., KC, epithelial neutrophil-activating peptide 78, JE, intercellular adhesion molecule 1, CD3, CD68, tumor necrosis factor alpha, interleukin-1beta, interleukin-6, inducible nitric oxide synthase, cyclooxygenase 2, matrix metalloproteinase 3, cathepsin B, and cathepsin K. NIRF in vivo imaging demonstrated that ML120B treatment dramatically reduced the amount of active proteases in the joints.

CONCLUSION: Our data demonstrate that IKK-2 inhibition in the murine model of antibody-induced arthritis suppresses both inflammation and joint destruction. In addition, this study highlights how gene expression profiling can facilitate the identification of surrogate biomarkers of disease activity and treatment response in an experimental model of arthritis.

Journal Article

IVIS, B16-F10-luc-G5, B16F10-luc-G5, B16-F10-luc, B16F10-luc,

OBJECTIVE: To determine whether chemotactic-metastasis, the preferential growth of melanomas towards areas of high lymphatic density, is CCL21/CCR7 dependent in vivo. Lymphatic endothelial cells (LECs) produce the chemokine CCL21. Metastatic melanoma cells express CCR7, its receptor, and exhibit chemotactic-metastasis, whereby metastatic cells recognise and grow towards areas of higher lymphatic density. METHODS: We used two in vivo models of directional growth towards depots of LECs of melanoma cells over-expressing CCR7. Injected LEC were tracked by intravital fluorescence microscopy, and melanoma growth by bioluminescence. RESULTS: Over-expression of the chemokine receptor CCR7 enables non-metastatic tumor cells to recognise and grow towards LECs (3.9 fold compared with control), but not blood endothelial cells (0.9 fold), in vitro and in vivo in the absence of increased lymphatic clearance. Chemotactic metastasis was inhibited by a CCL21 neutralising antibody (4-17% of control). Furthermore, CCR7 expression in mouse B16 melanomas resulted in in-transit metastasis (50-100% of mice) that was less often seen with control tumors (0-50%) in vivo. CONCLUSION: These results suggest that recognition of LEC by tumors expressing receptors for lymphatic specific ligands contributes towards the identification and invasion of lymphatics by melanoma cells and provides further evidence for a chemotactic metastasis model of tumor spread.

Journal Article

Animals; Anti-Bacterial Agents; Bioware; Connective Tissue; Diffusion; Drug Implants; Female; Mice; Mice, Inbred BALB C; Nitric Oxide; Polyvinyls; Prostheses and Implants; pXen-5; Staphylococcal Infections; Xen29

Infection of surgical meshes used in abdominal wall reconstructions often leads to removal of the implant and increases patient morbidity due to repetitive operations and hospital administrations. Treatment with antibiotics is ineffective due to the biofilm mode of growth of the infecting bacteria and bears the risk of inducing antibiotic resistance. Hence there is a need for alternative methods to prevent and treat mesh infection. Nitric oxide (NO)-releasing coatings have been demonstrated to possess bactericidal properties in vitro. It is the aim of this study to assess possible benefits of a low concentration NO-releasing carbon-based coating on monofilament polypropylene meshes with respect to infection control in vitro and in vivo. When applied on surgical meshes, NO-releasing coatings showed significant bactericidal effect on in vitro biofilms of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and CNS. However, using bioluminescent in vivo imaging, no beneficial effects of this NO-releasing coating on subcutaneously implanted surgical meshes in mice could be observed.

Journal Article

Animals; Anti-Infective Agents; Bacterial Adhesion; Biofilms; Bioware; Chromosomes, Bacterial; Colony Count, Microbial; Disease Models, Animal; Female; Mice; Mice, Inbred BALB C; Microbial Sensitivity Tests; Prostheses and Implants; pXen-5; Soft Tissue Infections; Staphylococcal Infections; Staphylococcus aureus; Xen29

Infection is the main cause of biomaterials-related failure. A simple technique to test in-vivo new antimicrobial and/or nonadhesive implant coatings is unavailable. Current in vitro methods for studying bacterial adhesion and growth on biomaterial surfaces lack the influence of the host immune system. Most in vivo methods to study biomaterials-related infections routinely involve implant-removal, preventing comprehensive longitudinal monitoring. In vivo imaging circumvents these drawbacks and is based on the use of noninvasive optical imaging of bioluminescent bacteria. Staphylococcus aureus Xen29 is genetically modified to be stably bioluminescent, by the introduction of a modified full lux operon onto its chromosome. Surgical meshes with adhering S. aureus Xen29 were implanted in mice and bacterial growth and spread into the surrounding tissue was monitored longitudinally from bioluminescence with a highly sensitive CCD camera. Distinct spatiotemporal bioluminescence patterns, extending beyond the mesh area into surrounding tissues were observed. After 10 days, the number of living organisms isolated from explanted meshes was found to correlate with bioluminescence prior to sacrifice of the animals. Therefore, it is concluded that in vivo imaging using bioluminescent bacteria is ideally suited to study antimicrobial coatings taking into account the host immune system. In addition, longitudinal monitoring of infection in one animal will significantly reduce the number of experiments and animals.