Citation Details

Journal Article

Xen36, Xen 36, Staphylococcus aureus Xen36, IVIS

Aims: To determine if nisin F-loaded self-setting brushite cement could control the growth of Staphylococcus aureus in vivo. Methods and Results: Brushite cement was prepared by mixing equimolar concentrations of beta-tricalcium phosphate and monocalcium phosphate monohydrate. Nisin F was added at 5.0%, 2.5% and 1.0% (w/w) and the cement moulded into cylinders. In vitro antibacterial activity was determined using a delayed agar diffusion assay. Release of nisin F from the cement was determined using BCA protein assays. Based on scanning electron microscopy and X-ray diffraction analysis, nisin F did not cause significant changes in cement structure or chemistry. Cement containing 5.0% (w/w) nisin F yielded the most promising in vitro results. Nisin F-loaded cement was implanted into a subcutaneous pocket on the back of mice and then infected with S. aureus Xen 36. Infection was monitored for 7 days, using an in vivo imaging system. Nisin F prevented S. aureus infection for 7 days and no viable cells were isolated from the implants. Conclusions: Nisin F-loaded brushite cement successfully prevented in vivo growth of S. aureus. Significance and Impact of the Study: Nisin F incorporated into bone cement may be used to control S. aureus infection in vivo. (c) 2012The Authors Journal of Applied Microbiology (c) 2012 The Society for Applied Microbiology.

Journal Article

MDA-MB-231-D3H2Ln, IVIS, Bioluminescence

N/A

Journal Article

4T1-luc2, ProSense, MMPSense, CRi, Maestro, IVIS Animals; Benzenesulfonates/diagnostic use; Diagnostic Imaging/instrumentation/*methods; Disease Models, Animal; Disease Progression; Fluorescent Dyes/*diagnostic use; Indoles/diagnostic use; Luminescent Measurements/instrumentation/*methods; Mammary Neoplasms, Experimental/*diagnosis/pathology; Mice

Bioluminescence imaging (BLI) has shown its appeal as a sensitive technique for in vivo whole body optical imaging. However, the development of injectable tumor-specific near-infrared fluorescent (NIRF) probes makes fluorescence imaging (FLI) a promising alternative to BLI in situations where BLI cannot be used or is unwanted (e.g., spontaneous transgenic tumor models, or syngeneic mice to study immune effects).In this study, we addressed the questions whether it is possible to detect tumor progression using FLI with appropriate sensitivity and how FLI correlates with BLI measurements. In addition, we explored the possibility to simultaneously detect multiple tumor characteristics by dual-wavelength FLI (~700 and ~800 nm) in combination with spectral unmixing. Using a luciferase-expressing 4T1-luc2 mouse breast cancer model and combinations of activatable and targeting NIRF probes, we showed that the activatable NIRF probes (ProSense680 and MMPSense680) and the targeting NIRF probes (IRDye 800CW 2-DG and IRDye 800CW EGF) were either activated by or bound to 4T1-luc2 cells. In vivo, we implanted 4T1-luc2 cells orthotopically in nude mice and were able to follow tumor progression longitudinally both by BLI and dual-wavelength FLI. We were able to reveal different probe signals within the tumor, which co-localized with immuno-staining. Moreover, we observed a linear correlation between the internal BLI signals and the FLI signals obtained from the NIRF probes. Finally, we could detect pulmonary metastases both by BLI and FLI and confirmed their presence histologically.Taken together, these data suggest that dual-wavelength FLI is a feasible approach to simultaneously detect different features of one tumor and to follow tumor progression with appropriate specificity and sensitivity. This study may open up new perspectives for the detection of tumors and metastases in various experimental models and could also have clinical applications, such as image-guided surgery.

Journal Article

AngioSense, Animals; Antineoplastic Agents/therapeutic use; Diagnostic Imaging/*methods; Female; Mammary Neoplasms, Animal/metabolism/pathology; Mice; Mice, Nude; Neoplasm Transplantation; Neovascularization, Pathologic/drug therapy/*pathology

In vivo angiogenesis assays provide more physiologically relevant information about tumor vascularization than in vitro studies because they take the complex interactions among cancer cells, endothelial cells, mural cells, and tumor stroma into consideration. Traditional microscopic assessment of vascular density conducted by immunostaining of tissue sections or by lectin angiogram visualization of tumor vessels is invasive and requires the sacrifice of tumor-bearing animals. Therefore, it prohibits longitudinal time-course observation in a single animal and requires a large number of animals at each time point to derive statistically-meaningful observations. Additionally, heterogenous behavior among different tumors will inevitably introduce individual biological variance that may obscure reliable interpretation of the results. While various artificial in vivo angiogenesis assays, such as the Matrigel implant assay, chick chorioallatoic membrane assay, and dorsal skin fold chamber assay have been developed and employed to more directly observe the progression of physiological angiogenesis, they can not appropriately assess tumor angiogenic progression or tumor vascular regression in response to therapeutic intervention. Here, we describe a noninvasive method and a detailed protocol that we have developed and optimized using the Olympus OV-100 in vivo imaging system for real-time high-resolution visualization and assessment of tumor angiogenesis and vascular response to anticancer therapies in live animals. We show that using this approach, tumor vessels can be monitored longitudinally through the whole vasculogenesis and angiogenesis process in the same mouse. Further, morphologic changes of the same vessel prior to and after drug treatments can be captured with microscopic high resolution. Moreover, the multichannel co-imaging capability of the OV-100 allows us to analyze and compare tumor vessel permeability before and after antiangiogenesis therapy by employing a near-infrared blood pool reagent, or by visualizing improved cytotoxic drug delivery upon tumor vessel normalization by using a fluorophore tagged drug. This noninvasive method can be readily applied to orthotopically transplanted breast cancer models as well as to subcutaneously-transplanted tumor models.

Journal Article

AngioSense, Abdomen; Animals; Imaging, Three-Dimensional; Liver/cytology; Mice; Mice, Transgenic; Microscopy/*instrumentation/*methods; Molecular Imaging/*instrumentation/*methods; Pancreas/cytology/ultrastructure; Time-Lapse Imaging

Intravital imaging of brain and bone marrow cells in the skull with subcellular resolution has revolutionized neurobiology, immunology and hematology. However, the application of this powerful technology in studies of abdominal organs has long been impeded by organ motion caused by breathing and heartbeat. Here we describe for the first time a simple device designated 'microstage' that effectively reduces organ motions without causing tissue lesions. Combining this microstage device with an upright intravital laser scanning microscope equipped with a unique stick-type objective lens, the system enables subcellular-level imaging of abdominal organs in live mice. We demonstrate that this technique allows for the quantitative analysis of subcellular structures and gene expressions in cells, the tracking of intracellular processes in real-time as well as three-dimensional image construction in the pancreas and liver of the live mouse. As the aforementioned analyses based on subcellular imaging could be extended to other intraperitoneal organs, the technique should offer great potential for investigation of physiological and disease-specific events of abdominal organs. The microstage approach adds an exciting new technique to the in vivo imaging toolbox.