Comparison of in vivo and ex vivo imaging of the microvasculature with 2-photon fluorescence microscopy

2016 ◽  
Author(s):  
Joe Steinman ◽  
Margaret Koletar ◽  
Bojana Stefanovic ◽  
John G. Sled
Keyword(s):  
Fluorescence Microscopy ◽  
Ex Vivo ◽  
Photon Fluorescence ◽  
Ex Vivo Imaging

scholarly journals Two-Photon Microscopy Allows Imaging and Characterization of Cochlear Microvasculature In Vivo

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Friedrich Ihler ◽  
Mattis Bertlich ◽  
Bernhard Weiss ◽  
Steffen Dietzel ◽  
Martin Canis
Keyword(s):  
Fluorescence Microscopy ◽  
Inner Ear ◽  
Ex Vivo ◽  
Small Scale ◽  
Published Data ◽  
Cochlear Blood Flow ◽  
Two Photon ◽  
Two Photon Fluorescence ◽  
Photon Fluorescence

Impairment of cochlear blood flow has been discussed as factor in the pathophysiology of various inner ear disorders. However, the microscopic study of cochlear microcirculation is limited due to small scale and anatomical constraints. Here, two-photon fluorescence microscopy is applied to visualize cochlear microvessels. Guinea pigs were injected with Fluorescein isothiocyanate- or Texas red-dextrane as plasma marker. Intravital microscopy was performed in four animals and explanted cochleae from four animals were studied. The vascular architecture of the cochlea was visualized up to a depth of90.0±22.7 μm. Imaging yielded a mean contrast-to-noise ratio (CNR) of3.3±1.7. Mean diameter in vivo was16.5±6.0 μm for arterioles and8.0±2.4 μm for capillaries. In explanted cochleae, the diameter of radiating arterioles and capillaries was measured with12.2±1.6 μm and6.6±1.0 μm, respectively. The difference between capillaries and arterioles was statistically significant in both experimental setups (P<0.001andP=0.022, two-way ANOVA). Measured vessel diameters in vivo and ex vivo were in agreement with published data. We conclude that two-photon fluorescence microscopy allows the investigation of cochlear microvessels and is potentially a valuable tool for inner ear research.

Two-photon Absorbing Probes and Their Use in Two-Photon Fluorescence Microscopy of Cells and Ex Vivo Imaging of Tumors

2011 ◽  
Author(s):  
Ciceron O. Yanez ◽  
Carolina D. Andrade ◽  
Alma R. Morales ◽  
Takeo Urakami ◽  
Masanobu Komatsu ◽  
...  
Keyword(s):  
Fluorescence Microscopy ◽  
Ex Vivo ◽  
Two Photon ◽  
Two Photon Fluorescence ◽  
Photon Fluorescence ◽  
Ex Vivo Imaging

Tumor Targeted Nanoparticles Improve Therapeutic Index of BCL2 and MCL1 dual inhibition

Blood ◽  
2020 ◽  
Author(s):  
Neeta Bala Tannan ◽  
Mandana T Manzari ◽  
Laurie Herviou ◽  
Mariana da Silva Ferreira ◽  
Connor J Hagen ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Therapeutic Index ◽  
Drug Dose ◽  
Hematological Toxicity ◽  
Bcl2 Family ◽  
Fold Reduction ◽  
Tumor Killing ◽  
Toxic Drugs ◽  
Ex Vivo Imaging

Cancer and normal cells utilize multiple anti-apoptotic BCL2 proteins to prevent cell death. Therapeutic targeting of multiple BCL2 family proteins enhances tumor killing, but is also associated with increased systemic toxicity. Here, we demonstrate that the dual targeting of MCL1 and BCL2 proteins, using the small molecules S63845 and venetoclax, induces durable remissions in mice harboring human DLBCL tumors but is accompanied by hematological toxicity and weight loss. To mitigate these toxicities, we encapsulated S63845 or venetoclax into nanoparticles targeting P-selectin that is enriched in tumor endothelial cells. In vivo and ex vivo imaging demonstrated preferential targeting of the nanoparticles to lymphoma tumors over vital organs. Mass-spectrometry analyses after nanoparticle drug administration confirmed tumor enrichment of the drug while reducing plasma levels. Furthermore, nanoparticle encapsulation allowed 3.5 to 6.5-fold reduction in drug dose, induced sustained remissions and minimized toxicity. Our results support the development of nanoparticles to deliver BH3 mimetic combinations in lymphoma and in general for toxic drugs in cancer therapy.

In-vivo near-infrared optical imaging of growing osteosarcoma cell lesions xenografted in mice: dual-channel quantitative evaluation of volume and mineralization

2011 ◽  
Vol 52 (9) ◽  
pp. 978-988 ◽  
Author(s):  
Hitoshi Nakayama ◽  
Tomoyuki Kawase ◽  
Kazuhiro Okuda ◽  
Larry F Wolff ◽  
Hiromasa Yoshie
Keyword(s):  
Optical Imaging ◽  
Near Infrared ◽  
Imaging Technique ◽  
Ex Vivo ◽  
Acquisition Time ◽  
Osteosarcoma Cell ◽  
Dual Channel ◽  
Nir Imaging ◽  
Ex Vivo Imaging

Background In a previous study using a rodent osteosarcoma-grafted rat model, in which cell-dependent mineralization was previously demonstrated to proportionally increase with growth, we performed a quantitative analysis of mineral deposit formation using 99mTc-HMDP and found some weaknesses, such as longer acquisition time and narrower dynamic ranges (i.e. images easily saturated). The recently developed near-infrared (NIR) optical imaging technique is expected to non-invasively evaluate changes in living small animals in a quantitative manner. Purpose To test the feasibility of NIR imaging with a dual-channel system as a better alternative for bone scintigraphy by quantitatively evaluating mineralization along with the growth of osteosarcoma lesions in a mouse-xenograft model. Material and Methods The gross volume and mineralization of osteosarcoma lesions were evaluated in living mice simultaneously with dual-channels by NIR dye-labeled probes, 2-deoxyglucose (DG) and pamidronate (OS), respectively. To verify these quantitative data, retrieved osteosarcoma lesions were then subjected to ex-vivo imaging, weighing under wet conditions, microfocus-computed tomography (μCT) analysis, and histopathological examination. Results Because of less scattering and no anatomical overlapping, as generally shown, specific fluorescence signals targeted to the osteosarcoma lesions could be determined clearly by ex-vivo imaging. These data were well positively correlated with the in-vivo imaging data ( r > 0.8, P < 0.02). Other good to excellent correlations ( r > 0.8, P < 0.02) were observed between DG accumulation and tumor gross volume and between OS accumulation and mineralization volume. Conclusion This in-vivo NIR imaging technique using DG and OS is sensitive to the level to simultaneously detect and quantitatively evaluate the growth and mineralization occuring in this type of osteosarcoma lesions of living mice without either invasion or sacrifice. By possible mutual complementation, this dual imaging system might be useful for accurate diagnosis even in the presence of overlapping tissues.

scholarly journals The Opportunities and Use of Imaging to Measure Target Engagement

2019 ◽  
Vol 25 (2) ◽  
pp. 127-136
Author(s):  
Juliana Maynard ◽  
Philippa Hart
Keyword(s):  
Ex Vivo ◽  
Clinical Success ◽  
Receptor Occupancy ◽  
Accurate Information ◽  
Target Engagement ◽  
Drug Molecule ◽  
Drug Discovery And Development ◽  
Ex Vivo Imaging

Lack of efficacy and poor safety outcomes are deemed to be the greatest causes of clinical failure of novel therapeutics. The use of biomarkers that give accurate information on target engagement, providing confidence that pharmacological activity in the target organ is being achieved, is key in optimizing clinical success. Without a measurement of target engagement, it can be very difficult to discern the basis for any lack of efficacy of a drug molecule within the pharmaceutical industry. Target engagement can be measured in both an in vitro and in vivo setting, and in recent years imaging measurements have been used frequently in drug discovery and development to assess target engagement and receptor occupancy in both human and animal models. From this perspective, we assess and look at the advancements in both in vivo and ex vivo imaging to demonstrate the enormous potential that imaging has as an application to provide a greater understanding of target engagement with a correlative therapeutic impact.

scholarly journals NIRF-Molecular Imaging with Synovial Macrophages-Targeting Vsig4 Nanobody for Disease Monitoring in a Mouse Model of Arthritis

2019 ◽  
Vol 20 (13) ◽  
pp. 3347 ◽  
Author(s):  
Fang Zheng ◽  
Siyu Luo ◽  
Zhenlin Ouyang ◽  
Jinhong Zhou ◽  
Huanye Mo ◽  
...  
Keyword(s):  
Fluorescence Microscopy ◽  
Near Infrared ◽  
Single Photon ◽  
Ex Vivo ◽  
Photon Emission ◽  
Joint Inflammation ◽  
Experimental Arthritis ◽  
Emission Computed Tomography ◽  
Nirf Imaging

Nanobody against V-set and Ig domain-containing 4 (Vsig4) on tissue macrophages, such as synovial macrophages, could visualize joint inflammation in multiple experimental arthritis models via single-photon emission computed tomography imaging. Here, we further addressed the specificity and assessed the potential for arthritis monitoring using near-infrared fluorescence (NIRF) Cy7-labeled Vsig4 nanobody (Cy7-Nb119). In vivo NIRF-imaging of collagen-induced arthritis (CIA) was performed using Cy7-Nb119. Signals obtained with Cy7-Nb119 or isotope control Cy7-NbBCII10 were compared in joints of naive mice versus CIA mice. In addition, pathological microscopy and fluorescence microscopy were used to validate the arthritis development in CIA. Cy7-Nb119 accumulated in inflamed joints of CIA mice, but not the naive mice. Development of symptoms in CIA was reflected in increased joint accumulation of Cy7-Nb119, which correlated with the conventional measurements of disease. Vsig4 is co-expressed with F4/80, indicating targeting of the increasing number of synovial macrophages associated with the severity of inflammation by the Vsig4 nanobody. NIRF imaging with Cy7-Nb119 allows specific assessment of inflammation in experimental arthritis and provides complementary information to clinical scoring for quantitative, non-invasive and economical monitoring of the pathological process. Nanobody labelled with fluorescence can also be used for ex vivo validation experiments using flow cytometry and fluorescence microscopy.

scholarly journals Highly Potent GalNAc-Conjugated Tiny LNA Anti-miRNA-122 Antisense Oligonucleotides

Pharmaceutics ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 817
Author(s):  
Tsuyoshi Yamamoto ◽  
Yahiro Mukai ◽  
Fumito Wada ◽  
Chisato Terada ◽  
Yukina Kayaba ◽  
...  
Keyword(s):  
Antisense Oligonucleotides ◽  
Ex Vivo ◽  
The Body ◽  
Locked Nucleic Acid ◽  
Imaging Studies ◽  
Phosphodiester Bond ◽  
Chemically Modified ◽  
Ex Vivo Imaging ◽  
Mirna Targeting

The development of clinically relevant anti-microRNA antisense oligonucleotides (anti-miRNA ASOs) remains a major challenge. One promising configuration of anti-miRNA ASOs called “tiny LNA (tiny Locked Nucleic Acid)” is an unusually small (~8-mer), highly chemically modified anti-miRNA ASO with high activity and specificity. Within this platform, we achieved a great enhancement of the in vivo activity of miRNA-122-targeting tiny LNA by developing a series of N-acetylgalactosamine (GalNAc)-conjugated tiny LNAs. Specifically, the median effective dose (ED50) of the most potent construct, tL-5G3, was estimated to be ~12 nmol/kg, which is ~300–500 times more potent than the original unconjugated tiny LNA. Through in vivo/ex vivo imaging studies, we have confirmed that the major advantage of GalNAc over tiny LNAs can be ascribed to the improvement of their originally poor pharmacokinetics. We also showed that the GalNAc ligand should be introduced into its 5′ terminus rather than its 3′ end via a biolabile phosphodiester bond. This result suggests that tiny LNA can unexpectedly be recognized by endogenous nucleases and is required to be digested to liberate the parent tiny LNA at an appropriate time in the body. We believe that our strategy will pave the way for the clinical application of miRNA-targeting small ASO therapy.

Multicolor core/shell silicananoparticles for in vivo and ex vivo imaging

Nanoscale ◽  
2012 ◽  
Vol 4 (3) ◽  
pp. 824-830 ◽  
Author(s):  
Enrico Rampazzo ◽  
Federico Boschi ◽  
Sara Bonacchi ◽  
Riccardo Juris ◽  
Marco Montalti ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Core Shell ◽  
Ex Vivo Imaging

IN VIVO NEAR-INFRARED FLUORESCENCE IMAGING OF HUMAN COLON ADENOCARCINOMA BY SPECIFIC IMMUNOTARGETING OF A TUMOR-ASSOCIATED MUCIN

2009 ◽  
Vol 02 (04) ◽  
pp. 407-422 ◽  
Author(s):  
RALPH S. DACOSTA ◽  
YING TANG ◽  
TUULA KALLIOMAKI ◽  
RAYMOND M. REILLY ◽  
ROBERT WEERSINK ◽  
...  
Keyword(s):  
Fluorescence Microscopy ◽  
Fluorescence Imaging ◽  
Normal Tissue ◽  
Near Infrared ◽  
Ex Vivo ◽  
Colon Adenocarcinoma ◽  
Human Colon ◽  
Human Colon Adenocarcinoma

Background and Aims: Accurate endoscopic detection of premalignant lesions and early cancers in the colon is essential for cure, since prognosis is closely related to lesion size and stage. Although it has great clinical potential, autofluorescence endoscopy has limited tumor-to-normal tissue image contrast for detecting small preneoplastic lesions. We have developed a molecularly specific, near-infrared fluorescent monoclonal antibody (CC49) bioconjugate which targets tumor-associated glycoprotein 72 (TAG72), as a contrast agent to improve fluorescence-based endoscopy of colon cancer. Methods: The fluorescent anti-TAG72 conjugate was evaluated in vitro and in vivo in athymic nude mice bearing human colon adenocarcinoma (LS174T) subcutaneous tumors. Autofluorescence, a fluorescent but irrelevant antibody and the free fluorescent dye served as controls. Fluorescent agents were injected intravenously, and in vivo whole body fluorescence imaging was performed at various time points to determine pharmacokinetics, followed by ex vivo tissue analysis by confocal fluorescence microscopy and histology. Results: Fluorescence microscopy and histology confirmed specific LS174T cell membrane targeting of labeled CC49 in vitro and ex vivo. In vivo fluorescence imaging demonstrated significant tumor-to-normal tissue contrast enhancement with labeled-CC49 at three hours post injection, with maximum contrast after 48 h. Accumulation of tumor fluorescence demonstrated that modification of CC49 antibodies did not alter their specific tumor-localizing properties, and was antibody-dependent since controls did not produce detectable tumor fluorescence. Conclusions: These results show proof-of-principle that our near-infrared fluorescent-antibody probe targeting a tumor-associated mucin detects colonic tumors at the molecular level in real time, and offer a basis for future improvement of image contrast during clinical fluorescence endoscopy.

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