Journal Article

*Breast Cancer; *Chemotherapy; *Genes; *Luciferase; Anatomy and Physiology; Biochemistry; Bioware; Cells(Biology); Diseases; Drugs; Efficacy; Gel Polymers; Gels; Growth(Physiology); Humans; Image Processing; In Vitro Analysis.; In Vivo Analysis; Luciferase Genes; Medicine and Medical Research; Metastasis; Mouse Models; Paclitaxel Sensitivity; Poloxamer Polymers; Polymers; Preclinical Evaluations; surgery; Synergism; Toxicity; Tumor Cell Lines

This project evaluated paclitaxel chemotherapy delivery from a gel polymer system placed into a wound bed following conservative (marginal) surgical removal of human breast cancers grown in nude mice. This delivery method was shown to control local tumor disease as well as assist in control of systemic metastasis. We established 5 human breast cancer cell lines within our laboratory. We elected purchase and implement a unique (luciferase) imaging system which allows in vivo imaging of tumor growth and metastasis (and subsequently decrease animal use). Tumor cell lines were transfected with the luciferase gene. In vitro testing of cell lines established paclitaxel sensitivity and showed a synergistic effect of delivering paclitaxel by the poloxamer polymer, especially for the chemotherapy resistant cell line, MCF-7-ADR. We completed the simultaneous evaluation of local and systemic toxicity, local, regional and systemic distribution and local and systemic efficacy of locally delivered paclitaxel chemotherapy following tumor removal using the MCF-7-ADR cell line in nude mice. Intracavitary administration of taxol in poloxamer was well tolerated (locally and systemically) afld resulted in significantly improved control of local tumor regrowth and comparable control of metastasis following marginal tumor removal as compared to intravenous paclitaxel (parent drug) . Sustained drug levels (from polymer delivery) were seen in plasma and liver tissue at 60 days.

Journal Article

Xen14, Xen 14, E. coli Xen14, IVIS, Animals; Anti-Infective Agents/*pharmacology/therapeutic use; Bacteria/*drug effects/pathogenicity; Bacterial Infections/drug therapy/*etiology; Biocompatible Materials/*adverse effects/chemistry; Biofilms; Coated Materials, Biocompatible/chemistry; Fluorescent Dyes/chemistry/metabolism; Humans; Image Enhancement/methods; Light; Luminescent Measurements/instrumentation/*methods; Luminescent Proteins/metabolism; Microscopy, Fluorescence/instrumentation/*methods; Prosthesis-Related Infections/drug therapy/microbiology; Sensitivity and Specificity

This review presents the current state of Bioluminescence and Fluorescent Imaging technologies (BLI and FLI) as applied to Biomaterial-Associated Infections (BAI). BLI offers the opportunity to observe the in vivo course of BAI in small animals without the need to sacrifice animals at different time points after the onset of infection. BLI is highly dependent on the bacterial cell metabolism which makes BLI a strong reporter of viable bacterial presence. Fluorescent sources are generally more stable than bioluminescent ones and specifically targeted, which renders the combination of BLI and FLI a promising tool for imaging BAI. The sensitivity and spatial resolution of both imaging tools are, however, dependent on the imaging system used and the tissue characteristics, which makes the interpretation of images, in terms of the location and shape of the illuminating source, difficult. Tomographic reconstruction of the luminescent source is possible in the most modern instruments, enabling exact localization of a colonized implant material, spreading of infecting organisms in surrounding tissue and immunological tissue reactions. BLI studies on BAI have successfully distinguished between different biomaterials with respect to the development and clearance of BAI in vivo, simultaneously reducing animal use and experimental variation. It is anticipated that bio-optical imaging will become an indispensable technology for the in vivo evaluation of antimicrobial coatings.

Journal Article

A549-luc-C8 cells; Bioware; Cell Line, Tumor; Cell Nucleus; Cell Separation; Electrophoresis; Humans; Microfluidic Analytical Techniques

This study reports a new biochip capable of cell separation and nucleus collection utilizing dielectrophoresis (DEP) forces in a microfluidic system comprising of micropumps and microvalves, operating in an automatic format. DEP forces operated at a low voltage (15 Vp-p) and at a specific frequency (16 MHz) can be used to separate cells in a continuous flow, which can be subsequently collected. In order to transport the cell samples continuously, a serpentine-shape (S-shape) pneumatic micropump device was constructed onto the chip device to drive the samples flow through the microchannel, which was activated by the pressurized air injection. The mixed cell samples were first injected into an inlet reservoir and driven through the DEP electrodes to separate specific samples. Finally, separated cell samples were collected individually in two outlet reservoirs controlled by microvalves. With the same operation principle, the nucleus of the specific cells can be collected after the cell lysis procedure. The pumping rate of the micropump was measured to be 39.8 microl/min at a pressure of 25 psi and a driving frequency of 28 Hz. For the cell separation process, the initial flow rate was 3 microl/min provided by the micropump. A throughput of 240 cells/min can be obtained by using the developed device. The DEP electrode array, microchannels, micropumps and microvalves are integrated on a microfluidic chip using micro-electro-mechanical-systems (MEMS) technology to perform several crucial procedures including cell transportation, separation and collection. The dimensions of the integrated chip device were measured to be 6x7 cm. By integrating an S-shape pump and pneumatic microvalves, different cells are automatically transported in the microchannel, separated by the DEP forces, and finally sorted to specific chambers. Experimental data show that viable and non-viable cells (human lung cancer cell, A549-luc-C8) can be successfully separated and collected using the developed microfluidic platform. The separation accuracy, depending on the DEP operating mode used, of the viable and non-viable cells are measured to be 84 and 81%, respectively. In addition, after cell lysis, the nucleus can be also collected using a similar scheme. The developed automatic microfluidic platform is useful for extracting nuclear proteins from living cells. The extracted nuclear proteins are ready for nuclear binding assays or the study of nuclear proteins.

Journal Article

AngioSense 680; Cancer; glioblastoma xenograft; mice; tumor vascularization

To obtain information on the occurrence and location of molecular events as well as to track target-specific probes such as antibodies or peptides, drugs or even cells non-invasively over time, optical imaging (OI) technologies are increasingly applied. Although OI strongly contributes to the advances made in preclinical research, it is so far, with the exception of optical coherence tomography (OCT), only very sparingly applied in clinical settings. Nevertheless, as OI technologies evolve and improve continuously and represent relatively inexpensive and harmful methods, their implementation as clinical tools for the assessment of children disease is increasing. This review focuses on the current preclinical and clinical applications as well as on the future potential of OI in the clinical routine. Herein, we summarize the development of different fluorescence and bioluminescence imaging techniques for microscopic and macroscopic visualization of microstructures and biological processes. In addition, we discuss advantages and limitations of optical probes with distinct mechanisms of target-detection as well as of different bioluminescent reporter systems. Particular attention has been given to the use of near-infrared (NIR) fluorescent probes enabling observation of molecular events in deeper tissue.

Journal Article

Animals, Ceftriaxone/therapeutic use, Cephalosporins/therapeutic use, Disease Models, Animal, Disease Susceptibility, Drosophila Proteins, Inflammation/genetics/immunology/microbiology/pathology, Listeria Infections/genetics/immunology, Listeria monocytogenes/genetics/immunology, Membrane Glycoproteins/ deficiency/genetics, Meningitis, Bacterial/ genetics/ immunology/microbiology/pathology, Mice, Mice, Inbred C57BL, Mice, Knockout, Pneumococcal Infections/genetics/immunology/microbiology/pathology, Receptors, Cell Surface/ deficiency/genetics, Streptococcus pneumoniae/ immunology, Time Factors, Toll-Like Receptor 2, Toll-Like Receptors IVIS, Xenogen, Xen10

Toll-like receptor-2 (TLR2) mediates host responses to gram-positive bacterial wall components. TLR2 function was investigated in a murine Streptococcus pneumoniae meningitis model in wild-type (wt) and TLR2-deficient (TLR2(-/-)) mice. TLR2(-/-) mice showed earlier time of death than wt mice (P<.02). Plasma interleukin-6 levels and bacterial numbers in blood and peripheral organs were similar for both strains. With ceftriaxone therapy, none of the wt but 27% of the TLR2(-/-) mice died (P<.04). Beyond 3 hours after infection, TLR2(-/-) mice had higher bacterial loads in brain than did wt mice, as assessed with luciferase-tagged S. pneumoniae by means of a Xenogen-CCD (charge-coupled device) camera. After 24 h, tumor necrosis factor activity was higher in cerebrospinal fluid of TLR2(-/-) than wt mice (P<.05) and was related to increased blood-brain barrier permeability (Evans blue staining, P<.02). In conclusion, the lack of TLR2 was associated with earlier death from meningitis, which was not due to sepsis but to reduced brain bacterial clearing, followed by increased intrathecal inflammation.