Citation Details

Journal Article

Animals; Biological Markers; Bioware; Diagnostic Imaging; Image Processing, Computer-Assisted; Luminescent Measurements; Luminescent Proteins; Molecular Probes; Optical Devices; Optical Phenomena; PC-3M-luc; Reproducibility of Results

There has recently been an explosion in the availability of new technologies to noninvasively detect biological processes in preclinical models. One such modality, optical imaging, comprises using bioluminescent and fluorescent reporters and probes to repetitively interrogate molecular events and monitor disease progression in animal models. This review includes an overview of optical imaging technologies (e.g., hardware, reporters, probes) available for small animal imaging and their application in monitoring disease progression, therapeutic efficacy, and molecular processes such as proliferation, apoptosis, and angiogenesis. Also discussed are some of the challenges associated with in vivo optical imaging and the necessary controls and biological correlates one must include in experimental design and interpretation for successful preclinical studies.

Journal Article

4T1-luc2; Animals; Bioware; Cell Line, Tumor; Female; Luciferases; Luminescent Measurements; Mammary Neoplasms, Experimental; Mice; Mice, Nude

4T1 mouse mammary tumor cells can be implanted sub-cutaneously in nu/nu mice to form palpable tumors in 15 to 20 days. This xenograft tumor model system is valuable for the pre-clinical in vivo evaluation of putative antitumor compounds. The 4T1 cell line has been engineered to constitutively express the firefly luciferase gene (luc2). When mice carrying 4T1-luc2 tumors are injected with Luciferin the tumors emit a visual light signal that can be monitored using a sensitive optical imaging system like the IVIS Spectrum. The photon flux from the tumor is proportional to the number of light emitting cells and the signal can be measured to monitor tumor growth and development. IVIS is calibrated to enable absolute quantitation of the bioluminescent signal and longitudinal studies can be performed over many months and over several orders of signal magnitude without compromising the quantitative result. Tumor growth can be monitored for several days by bioluminescence before the tumor size becomes palpable or measurable by traditional physical means. This rapid monitoring can provide insight into early events in tumor development or lead to shorter experimental procedures. Tumor cell death and necrosis due to hypoxia or drug treatment is indicated early by a reduction in the bioluminescent signal. This cell death might not be accompanied by a reduction in tumor size as measured by physical means. The ability to see early events in tumor necrosis has significant impact on the selection and development of therapeutic agents. Quantitative imaging of tumor growth using IVIS provides precise quantitation and accelerates the experimental process to generate results.

Journal Article

Animals; Anti-Bacterial Agents; Antimicrobial Cationic Peptides; Bioware; Cathelicidins; Chronic Disease; Drug Carriers; Genetic Engineering; Male; Rats; Rats, Inbred F344; Surgical Flaps; Wound Infection; Xen29

BACKGROUND The success of antimicrobial therapy has been impaired by the emergence of resistant bacterial strains. Antimicrobial peptides are ubiquitous proteins that are part of the innate immune system and are successful against such antibiotic-resistant microorganisms. The authors have previously demonstrated the feasibility of protein delivery via microvascular free flap gene therapy and here they examine this approach for recalcitrant infections. METHODS The authors investigated the production of the human cathelicidin antimicrobial peptide-LL37, delivered by ex vivo transduction of the rodent superficial inferior epigastric free flap with Ad/CMV-LL37. The vascular permeabilizing agent vascular endothelial growth factor (VEGF) was co-administered during ex vivo transduction with adenoviral vectors in an attempt to augment transduction efficiency. A rodent model of chronic wound/foreign body infection seeded with bioluminescent Staphylococcus aureus was used to assess the biological efficacy of delivering therapeutic antimicrobial genes using this technology. RESULTS The authors were successful in demonstrating significant LL37 expression, which persisted for 14 days after ex vivo transduction with Ad/CMV-LL37. Transduction efficiency was significantly improved with the co-administration of 5 micrograms of VEGF during transduction without significantly increasing systemic dissemination of adenovirus or systemic toxicity. They were able to demonstrate in the rodent model of chronic wound/foreign body infections a significant reduction in bacterial loads from infected catheters following transduction with Ad/CMV-LL37 and increased bacterial clearance. CONCLUSION This study demonstrates for the first time that microbicidal gene therapy via microvascular free flaps is able to clear chronic infections such as occurs with osteomyelitis resulting from trauma or an infected foreign body [corrected]

Journal Article

Antineoplastic Agents; Bioware; Breast Neoplasms; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cell Survival; Diphosphonates; Esterification; Female; Humans; Hydrophobic and Hydrophilic Interactions; MDA-MB-231-D3H2LN cells; Neoplasm Metastasis; Structure-Activity Relationship

BACKGROUND Although there was growing evidence in the potential use of Bisphosphonates (BPs) in cancer therapy, their strong osseous affinities that contrast their poor soft tissue uptake limited their use. Here, we developed a new strategy to overcome BPs hydrophilicity by masking the phosphonic acid through organic protecting groups and introducing hydrophobic functions in the side chain. METHODOLOGY/PRINCIPAL FINDINGS We synthesized non-nitrogen BPs (non N-BPs) containing bromobenzyl group (BP7033Br) in their side chain that were symmetrically esterified with hydrophobic 4-methoxphenyl (BP7033BrALK) and assessed their effects on breast cancer estrogen-responsive cells (T47D, MCF-7) as well as on non responsive ones (SKBR3, MDA-MB-231 and its highly metastatic derived D3H2LN subclone). BP7033Br ALK was more efficient in inhibiting tumor cell proliferation, migration and survival when compared to BP7033Br. Although both compounds inhibited tumor growth without side effects, only BP7033Br ALK abrogated tumor angiogenesis and D3H2LN cells-induced metastases formation. CONCLUSION/SIGNIFICANCE Taken together these data suggest the potential therapeutic use of this new class of esterified Bisphosphonates (BPs) in the treatment of tumor progression and metastasis without toxic adverse effects.

Journal Article

Acinetobacter baumannii; Acinetobacter Infections; Animals; Anti-Bacterial Agents; Bioware; Colistin; Disease Models, Animal; Drug Resistance, Multiple, Bacterial; Female; Fractures, Bone; Mice; Mice, Inbred C57BL; Osteomyelitis; Xen29

Osteomyelitis (OM) from multidrug-resistant (MDR) Acinetobacter has emerged in >30% of combat-related injuries in Iraq and Afghanistan. While most of these strains are sensitive to colistin, the drug is not available in bone void fillers for local high-dose delivery. To address this, we developed a mouse model with MDR strains isolated from wounded military personnel. In contrast to S. aureus OM, which is osteolytic and characterized by biofilm in necrotic bone, A. baumannii OM results in blastic lesions that do not contain apparent biofilm. We also found that mice mount a specific IgG response against three proteins (40, 47, and 56 kDa) regardless of the strain used, suggesting that these may be immuno-dominant antigens. PCR for the A. baumannii-specific parC gene confirmed a 100% infection rate with 75% of the MDR strains, and in vitro testing confirmed that all strains were sensitive to colistin. We also developed a real-time quantitative PCR (RTQ-PCR) assay that could detect as few as 10 copies of parC in a sample. To demonstrate the efficacy of colistin prophylaxis in this model, mice were treated with either parenteral colistin (0.2 mg colistinmethate i.m. for 7 days), local colistin (PMMA bead impregnated with 1.0 mg colistin sulfate), or an unloaded PMMA bead control. While the parenteral colistin failed to demonstrate any significant effects versus the placebo, the colistin PMMA bead significantly reduced the infection rate such that only 29.2% of the mice had detectable levels of parC at 19 days (p < 0.05 vs. i.m. colistin and placebo).