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      1. Author :
        Orihuela, C. J.; Radin, J. N.; Sublett, J. E.; Gao, G.; Kaushal, D.; Tuomanen, E. I.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2004
      5. Publication :
        Infection and Immunity
      6. Products :
      7. Volume :
        72
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        IVIS, Xenogen, Xen7, Xen35
      12. Abstract :
        Streptococcus pneumoniae is a leading cause of invasive bacterial disease. This is the first study to examine the expression of S. pneumoniae genes in vivo by using whole-genome microarrays available from The Institute for Genomic Research. Total RNA was collected from pneumococci isolated from infected blood, infected cerebrospinal fluid, and bacteria attached to a pharyngeal epithelial cell line in vitro. Microarray analysis of pneumococcal genes expressed in these models identified body site-specific patterns of expression for virulence factors, transporters, transcription factors, translation-associated proteins, metabolism, and genes with unknown function. Contributions to virulence predicted for several unknown genes with enhanced expression in vivo were confirmed by insertion duplication mutagenesis and challenge of mice with the mutants. Finally, we cross-referenced our results with previous studies that used signature-tagged mutagenesis and differential fluorescence induction to identify genes that are potentially required by a broad range of pneumococcal strains for invasive disease.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/15385455
      14. Call Number :
        141856
      15. Serial :
        6874
      1. Author :
        Orihuela, Carlos J; Gao, Geli; Francis, Kevin P; Yu, Jun; Tuomanen, Elaine I
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2004
      5. Publication :
        The Journal of infectious diseases
      6. Products :
      7. Volume :
        190
      8. Issue :
        9
      9. Page Numbers :
        1661-1669
      10. Research Area :
        N/A
      11. Keywords :
        Animals; Bacteremia; Bacterial Proteins; Cerebrospinal Fluid; Disease Models, Animal; Female; Lung; Meningitis, Pneumococcal; Mice; Mice, Inbred BALB C; Mutation; N-Acetylmuramoyl-L-alanine Amidase; Nasopharynx; Neuraminidase; Pneumococcal Infections; Pneumonia, Pneumococcal; Pyruvate Oxidase; Streptococcus pneumoniae; Streptolysins; Virulence Factors; Xen7
      12. Abstract :
        We assessed the ability of Streptococcus pneumoniae mutants deficient in either choline binding protein A (CbpA), pneumolysin (Pln), pyruvate oxidase (SpxB), autolysin (LytA), pneumococcal surface protein A, or neuraminidase A (NanA) to replicate in distinct anatomical sites and translocate from one site to the next. Intranasal, intratracheal, and intravenous models of disease were assessed in 4-week-old BALB/cJ mice by quantitation of bacterial titers in the relevant organs. Mice were also observed by use of real-time bioluminescent imaging (BLI). BLI allowed visualization of the bacteria in sites not tested by sampling. All mutants were created in D39 Xen7, a fully virulent derivative of capsular type 2 strain D39 that contains an optimized luxABCDE cassette. NanA, SpxB, and, to a lesser extent, CbpA contributed to prolonged nasopharyngeal colonization, whereas CbpA and NanA contributed to the transition to the lower respiratory tract. Once lung infection was established, Pln, SpxB, and LytA contributed to bacterial replication in the lungs and translocation to the bloodstream. In the bloodstream, only Pln and LytA were required for high-titer replication, whereas CbpA was required for invasion of the cerebrospinal fluid. We conclude that transitions between body sites require virulence determinants distinct from those involved in organ-specific replication.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/15478073
      14. Call Number :
        PKI @ catherine.lautenschlager @
      15. Serial :
        10002
      1. Author :
        N/A
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2005
      5. Publication :
        Nature
      6. Products :
      7. Volume :
        433
      8. Issue :
        7025
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Aging; Animals; Antigens, CD36; Cell Line; Dimerization; Ethylnitrosourea; Gene Deletion; Glycerides; Homozygote; Humans; Immunologic Deficiency Syndromes; Lipopeptides; Membrane Glycoproteins; Mice; Mice, Inbred C57BL; Mice, Knockout; Mutagenesis; Mutation; Oligopeptides; Peptidoglycan; Phenotype; Receptors, Cell Surface; Signal Transduction; Staphylococcal Infections; Staphylococcus aureus; Toll-Like Receptor 2; Toll-Like Receptors; Tumor Necrosis Factor-alpha; Zymosan
      12. Abstract :
        Toll-like receptor 2 (TLR2) is required for the recognition of numerous molecular components of bacteria, fungi and protozoa. The breadth of the ligand repertoire seems unusual, even if one considers that TLR2 may form heteromers with TLRs 1 and 6 (ref. 12), and it is likely that additional proteins serve as adapters for TLR2 activation. Here we show that an N-ethyl-N-nitrosourea-induced nonsense mutation of Cd36 (oblivious) causes a recessive immunodeficiency phenotype in which macrophages are insensitive to the R-enantiomer of MALP-2 (a diacylated bacterial lipopeptide) and to lipoteichoic acid. Homozygous mice are hypersusceptible to Staphylococcus aureus infection. Cd36(obl) macrophages readily detect S-MALP-2, PAM(2)CSK(4), PAM(3)CSK(4) and zymosan, revealing that some--but not all--TLR2 ligands are dependent on CD36. Already known as a receptor for endogenous molecules, CD36 is also a selective and nonredundant sensor of microbial diacylglycerides that signal via the TLR2/6 heterodimer.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/15690042
      14. Call Number :
        PKI @ catherine.lautenschlager @
      15. Serial :
        9991
      1. Author :
        Xiong, Y. Q.; Willard, J.; Kadurugamuwa, J. L.; Yu, J.; Francis, K. P.; Bayer, A. S.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2005
      5. Publication :
        Antimicrobial Agents and Chemotherapy
      6. Products :
      7. Volume :
        49
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        IVIS, Xenogen; Bioware; Xen29
      12. Abstract :
        Therapeutic options for invasive Staphylococcus aureus infections have become limited due to rising antimicrobial resistance, making relevant animal model testing of new candidate agents more crucial than ever. In the present studies, a rat model of aortic infective endocarditis (IE) caused by a bioluminescently engineered, biofilm-positive S. aureus strain was used to evaluate real-time antibiotic efficacy directly. This strain was vancomycin and cefazolin susceptible but gentamicin resistant. Bioluminescence was detected and quantified daily in antibiotic-treated and control animals with IE, using a highly sensitive in vivo imaging system (IVIS). Persistent and increasing cardiac bioluminescent signals (BLS) were observed in untreated animals. Three days of vancomycin therapy caused significant reductions in both cardiac BLS (>10-fold versus control) and S. aureus densities in cardiac vegetations (P < 0.005 versus control). However, 3 days after discontinuation of vancomycin therapy, a greater than threefold increase in cardiac BLS was observed, indicating relapsing IE (which was confirmed by quantitative culture). Cefazolin resulted in modest decreases in cardiac BLS and bacterial densities. These microbiologic and cardiac BLS differences during therapy correlated with a longer time-above-MIC for vancomycin (>12 h) than for cefazolin (?4 h). Gentamicin caused neither a reduction in cardiac S. aureus densities nor a reduction in BLS. There were significant correlations between cardiac BLS and S. aureus densities in vegetations in all treatment groups. These data suggest that bioluminescent imaging provides a substantial advance in the real-time monitoring of the efficacy of therapy of invasive S. aureus infections in live animals.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/15743898
      14. Call Number :
        144577
      15. Serial :
        7474
      1. Author :
        Yu, Jun; Wu, Jenny; Francis, Kevin P; Purchio, Tony F; Kadurugamuwa, Jagath L
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2005
      5. Publication :
        The Journal of antimicrobial chemotherapy
      6. Products :
      7. Volume :
        55
      8. Issue :
        4
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Animals; Anti-Bacterial Agents; Biofilms; Bioware; Drug Resistance, Bacterial; Mice; Mutation; Rifampin; Staphylococcus aureus; Xen29
      12. Abstract :
        OBJECTIVES To investigate in vivo fitness of rifampicin-resistant Staphylococcus aureus mutants in a mouse biofilm model using bioluminescence imaging. MATERIALS AND METHODS S. aureus was engineered with a luciferase operon to emit bioluminescence that can be detected in vivo using an IVIS imaging system. Two rifampicin-resistant strains of S. aureus that were previously isolated from animals undergoing rifampicin treatment, S464P (resistant to low concentrations of rifampicin) and H481Y (resistant to high concentrations of rifampicin), were characterized and then compared with their parental strain for in vivo fitness to form biofilm infections in the absence of rifampicin. RESULTS The mutant S464P showed better adaptation to in vivo growth than either the parental strain or H481Y without selective pressure. Six days after implanting pre-colonized catheters, bioluminescent signals were seen from 100% of the catheters coated by the mutant S464P. In comparison, only 83% and 61% of the catheters coated by the parental strain and H481Y, respectively, maintained a signal in vivo. Rifampicin treatment of S464P biofilms in vivo resulted in a slight decline, but earlier rebound in bioluminescence from these catheters compared with the parental signal, whereas rifampicin had no affect on bioluminescence in mice infected with mutant H481Y. CONCLUSIONS The mutant with low-level rifampicin resistance appears to be better adapted to in vivo growth than the mutant that has high-level rifampicin resistance. Moreover, the former mutant may actually have a slight competitive advantage over the rifampicin-susceptible strain (parental), raising awareness for the occurrence of such strains in clinical environments.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/15743898
      14. Call Number :
        PKI @ catherine.lautenschlager @
      15. Serial :
        9055
      1. Author :
        Kadurugamuwa, J. L.; Modi, K.; Yu, J.; Francis, K. P.; Purchio, T.; Contag, P. R.
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2005
      5. Publication :
        Infection and Immunity
      6. Products :
      7. Volume :
        73
      8. Issue :
        N/A
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Animals, Diagnostic Imaging/ methods, Female, Mice, Microscopy, Electron, Scanning, Photons, Proteus Infections/ diagnosis, Proteus mirabilis/drug effects/isolation & purification, Pseudomonas Infections/ diagnosis, Pseudomonas aeruginosa/drug effects/isolation & purification, Urinary Catheterization/ adverse effects, Urinary Tract Infections/ diagnosis IVIS, Xenogen, Xen5, Xen44
      12. Abstract :
        Urinary tract infections (UTIs) are among the most common bacterial infections acquired by humans, particularly in catheterized patients. A major problem with catheterization is the formation of bacterial biofilms on catheter material and the risk of developing persistent UTIs that are difficult to monitor and eradicate. To better understand the course of UTIs and allow more accurate studies of in vivo antibiotic efficacy, we developed a catheter-based biofilm infection model with mice, using bioluminescently engineered bacteria. Two important urinary tract pathogens, Pseudomonas aeruginosa and Proteus mirabilis, were made bioluminescent by stable insertion of a complete lux operon. Segments of catheter material (precolonized or postimplant infected) with either pathogen were placed transurethrally in the lumen of the bladder by using a metal stylet without surgical manipulation. The bioluminescent strains were sufficiently bright to be readily monitored from the outside of infected animals, using a low-light optical imaging system, including the ability to trace the ascending pattern of light-emitting bacteria through ureters to the kidneys. Placement of the catheter in the bladder not only resulted in the development of strong cystitis that persisted significantly longer than in mice challenged with bacterial suspensions alone but also required prolonged antibiotic treatment to reduce the level of infection. Treatment of infected mice for 4 days with ciprofloxacin at 30 mg/kg of body weight twice a day cured cystitis and renal infection in noncatheterized mice. Similarly, ciprofloxacin reduced the bacterial burden to undetectable levels in catheterized mice but did not inhibit rebound of the infection upon cessation of antibiotic therapy. This methodology easily allows spatial information to be monitored sequentially throughout the entire disease process, including ascending UTI, treatment efficacy, and relapse, all without exogenous sampling, which is not possible with conventional methods.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/15972473
      14. Call Number :
        139333
      15. Serial :
        7110
      1. Author :
        Lambrechts, Saskia A G; Demidova, Tatiana N; Aalders, Maurice C G; Hasan, Tayyaba; Hamblin, Michael R
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2005
      5. Publication :
        Photochemical & photobiological sciences: Official journal of the European Photochemistry Association and the European Society for Photobiology
      6. Products :
      7. Volume :
        4
      8. Issue :
        7
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Animals; Bioware; Burns; Mice; Photochemotherapy; Staphylococcal Infections; Staphylococcus aureus; Xen8.1
      12. Abstract :
        The rise of multiply antibiotic resistant bacteria has led to searches for novel antimicrobial therapies to treat infections. Photodynamic therapy (PDT) is a potential candidate; it uses the combination of a photosensitizer with visible light to produce reactive oxygen species that lead to cell death. We used PDT mediated by meso-mono-phenyl-tri(N-methyl-4-pyridyl)-porphyrin (PTMPP) to treat burn wounds in mice with established Staphylococcus aureus infections The third degree burn wounds were infected with bioluminescent S. aureus. PDT was applied after one day of bacterial growth by adding a 25% DMSO/500 microM PTMPP solution to the wound followed by illumination with red light and periodic imaging of the mice using a sensitive camera to detect the bioluminescence. More than 98% of the bacteria were eradicated after a light dose of 210 J cm(-2) in the presence of PTMPP. However, bacterial re-growth was observed. Light alone or PDT both delayed the wound healing. These data suggest that PDT has the potential to rapidly reduce the bacterial load in infected burns. The treatment needs to be optimized to reduce wound damage and prevent recurrence.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/15986057
      14. Call Number :
        PKI @ catherine.lautenschlager @
      15. Serial :
        9993
      1. Author :
        Jenkins, Darlene E; Hornig, Yvette S; Oei, Yoko; Dusich, Joan; Purchio, Tony
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2005
      5. Publication :
        Breast cancer research: BCR
      6. Products :
      7. Volume :
        7
      8. Issue :
        4
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Animals; Bioware; Breast Neoplasms; Disease Models, Animal; Female; Humans; Luciferases; Mammary Neoplasms, Animal; MDA-MB-231-D3H2LN cells; Mice; Mice, Nude; Neoplasm Metastasis; Plasmids; Transplantation, Heterologous; Tumor Cells, Cultured
      12. Abstract :
        INTRODUCTION Our goal was to generate xenograft mouse models of human breast cancer based on luciferase-expressing MDA-MB-231 tumor cells that would provide rapid mammary tumor growth; produce metastasis to clinically relevant tissues such as lymph nodes, lung, and bone; and permit sensitive in vivo detection of both primary and secondary tumor sites by bioluminescent imaging. METHOD Two clonal cell sublines of human MDA-MB-231 cells that stably expressed firefly luciferase were isolated following transfection of the parental cells with luciferase cDNA. Each subline was passaged once or twice in vivo to enhance primary tumor growth and to increase metastasis. The resulting luciferase-expressing D3H1 and D3H2LN cells were analyzed for long-term bioluminescent stability, primary tumor growth, and distal metastasis to lymph nodes, lungs, bone and soft tissues by bioluminescent imaging. Cells were injected into the mammary fat pad of nude and nude-beige mice or were delivered systemically via intracardiac injection. Metastasis was also evaluated by ex vivo imaging and histologic analysis postmortem. RESULTS The D3H1 and D3H2LN cell lines exhibited long-term stable luciferase expression for up to 4-6 months of accumulative tumor growth time in vivo. Bioluminescent imaging quantified primary mammary fat pad tumor development and detected early spontaneous lymph node metastasis in vivo. Increased frequency of spontaneous lymph node metastasis was observed with D3H2LN tumors as compared with D3H1 tumors. With postmortem ex vivo imaging, we detected additional lung micrometastasis in mice with D3H2LN mammary tumors. Subsequent histologic evaluation of tissue sections from lymph nodes and lung lobes confirmed spontaneous tumor metastasis at these sites. Following intracardiac injection of the MDA-MB-231-luc tumor cells, early metastasis to skeletal tissues, lymph nodes, brain and various visceral organs was detected. Weekly in vivo imaging data permitted longitudinal analysis of metastasis at multiple sites simultaneously. Ex vivo imaging data from sampled tissues verified both skeletal and multiple soft tissue tumor metastasis. CONCLUSION This study characterized two new bioluminescent MDA-MB-231-luc human breast carcinoma cell lines with enhanced tumor growth and widespread metastasis in mice. Their application to current xenograft models of breast cancer offers rapid and highly sensitive detection options for preclinical assessment of anticancer therapies in vivo.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/15987449
      14. Call Number :
        PKI @ catherine.lautenschlager @
      15. Serial :
        8960
      1. Author :
        Jenkins, Darlene E; Hornig, Yvette S; Oei, Yoko; Dusich, Joan; Purchio, Tony
      2. Title :
      3. Type :
        Journal Article
      4. Year :
        2005
      5. Publication :
        Breast cancer research: BCR
      6. Products :
      7. Volume :
        7
      8. Issue :
        4
      9. Page Numbers :
        N/A
      10. Research Area :
        N/A
      11. Keywords :
        Animals; Bioware; Breast Neoplasms; Disease Models, Animal; Female; Humans; Luciferases; Mammary Neoplasms, Animal; MDA-MB-231-D3H1 cells; Mice; Mice, Nude; Neoplasm Metastasis; Plasmids; Transplantation, Heterologous; Tumor Cells, Cultured
      12. Abstract :
        INTRODUCTION Our goal was to generate xenograft mouse models of human breast cancer based on luciferase-expressing MDA-MB-231 tumor cells that would provide rapid mammary tumor growth; produce metastasis to clinically relevant tissues such as lymph nodes, lung, and bone; and permit sensitive in vivo detection of both primary and secondary tumor sites by bioluminescent imaging. METHOD Two clonal cell sublines of human MDA-MB-231 cells that stably expressed firefly luciferase were isolated following transfection of the parental cells with luciferase cDNA. Each subline was passaged once or twice in vivo to enhance primary tumor growth and to increase metastasis. The resulting luciferase-expressing D3H1 and D3H2LN cells were analyzed for long-term bioluminescent stability, primary tumor growth, and distal metastasis to lymph nodes, lungs, bone and soft tissues by bioluminescent imaging. Cells were injected into the mammary fat pad of nude and nude-beige mice or were delivered systemically via intracardiac injection. Metastasis was also evaluated by ex vivo imaging and histologic analysis postmortem. RESULTS The D3H1 and D3H2LN cell lines exhibited long-term stable luciferase expression for up to 4-6 months of accumulative tumor growth time in vivo. Bioluminescent imaging quantified primary mammary fat pad tumor development and detected early spontaneous lymph node metastasis in vivo. Increased frequency of spontaneous lymph node metastasis was observed with D3H2LN tumors as compared with D3H1 tumors. With postmortem ex vivo imaging, we detected additional lung micrometastasis in mice with D3H2LN mammary tumors. Subsequent histologic evaluation of tissue sections from lymph nodes and lung lobes confirmed spontaneous tumor metastasis at these sites. Following intracardiac injection of the MDA-MB-231-luc tumor cells, early metastasis to skeletal tissues, lymph nodes, brain and various visceral organs was detected. Weekly in vivo imaging data permitted longitudinal analysis of metastasis at multiple sites simultaneously. Ex vivo imaging data from sampled tissues verified both skeletal and multiple soft tissue tumor metastasis. CONCLUSION This study characterized two new bioluminescent MDA-MB-231-luc human breast carcinoma cell lines with enhanced tumor growth and widespread metastasis in mice. Their application to current xenograft models of breast cancer offers rapid and highly sensitive detection options for preclinical assessment of anticancer therapies in vivo.
      13. URL :
        http://www.ncbi.nlm.nih.gov/pubmed/15987449
      14. Call Number :
        PKI @ catherine.lautenschlager @
      15. Serial :
        8993
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