Ex Vivo and In Vivo Imaging and Biodistribution of Aptamers Targeting the Human Matrix MetalloProtease-9 in Melanomas

The ability to visualize the immune response with radioligands targeted to immune cells will enhance our understanding of cellular responses in inflammatory diseases. Peripheral benzodiazepine receptors (PBR) are present in monocytes and neutrophils as well as in lung tissue. We used lipopolysaccharide (LPS) as a model of inflammation to assess whether the PBR could be used as a noninvasive marker of inflammation in the lungs. Planar imaging of mice administrated 10 or 30 mg/kg LPS showed increased [123I]-( R)-PK11195 radioactivity in the thorax 2 days after LPS treatment relative to control. Following imaging, lungs from control and LPS-treated mice were harvested for ex vivo gamma counting and showed significantly increased radioactivity above control levels. The specificity of the PBR response was determined using a blocking dose of nonradioactive PK11195 given 30 min prior to radiotracer injection. Static planar images of the thorax of nonradioactive PK11195 pretreated animals showed a significantly lower level of radiotracer accumulation in control and in LPS-treated animals ( p < .05). These data show that LPS induces specific increases in PBR ligand binding in the lungs. We also used in vivo small-animal PET studies to demonstrate increased [11C]-( R)-PK11195 accumulation in the lungs of LPS-treated mice. This study suggests that measuring PBR expression using in vivo imaging techniques may be a useful biomarker to image lung inflammation.

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Convergent molecular, cellular, and cortical neuroimaging signatures of major depressive disorder

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2008004117 ◽

2020 ◽

Vol 117 (40) ◽

pp. 25138-25149

Author(s):

Kevin M. Anderson ◽

Meghan A. Collins ◽

Ru Kong ◽

Kacey Fang ◽

Jingwei Li ◽

...

Keyword(s):

Major Depressive Disorder ◽

Negative Affect ◽

Depressive Disorder ◽

Single Cell ◽

In Vivo Imaging ◽

Ex Vivo ◽

Integrated Analysis ◽

Down Regulation ◽

Major Depressive

Major depressive disorder emerges from the complex interactions of biological systems that span genes and molecules through cells, networks, and behavior. Establishing how neurobiological processes coalesce to contribute to depression requires a multiscale approach, encompassing measures of brain structure and function as well as genetic and cell-specific transcriptional data. Here, we examine anatomical (cortical thickness) and functional (functional variability, global brain connectivity) correlates of depression and negative affect across three population-imaging datasets: UK Biobank, Brain Genomics Superstruct Project, and Enhancing NeuroImaging through Meta Analysis (ENIGMA; combined n ≥ 23,723). Integrative analyses incorporate measures of cortical gene expression, postmortem patient transcriptional data, depression genome-wide association study (GWAS), and single-cell gene transcription. Neuroimaging correlates of depression and negative affect were consistent across three independent datasets. Linking ex vivo gene down-regulation with in vivo neuroimaging, we find that transcriptional correlates of depression imaging phenotypes track gene down-regulation in postmortem cortical samples of patients with depression. Integrated analysis of single-cell and Allen Human Brain Atlas expression data reveal somatostatin interneurons and astrocytes to be consistent cell associates of depression, through both in vivo imaging and ex vivo cortical gene dysregulation. Providing converging evidence for these observations, GWAS-derived polygenic risk for depression was enriched for genes expressed in interneurons, but not glia. Underscoring the translational potential of multiscale approaches, the transcriptional correlates of depression-linked brain function and structure were enriched for disorder-relevant molecular pathways. These findings bridge levels to connect specific genes, cell classes, and biological pathways to in vivo imaging correlates of depression.

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Synthesis, Ex Vivo Evaluation, and Radiolabeling of Potent 1,5-Diphenylpyrrolidin-2-one Cannabinoid Subtype-1 Receptor Ligands as Candidates for In Vivo Imaging

Journal of Medicinal Chemistry ◽

10.1021/jm800416m ◽

2008 ◽

Vol 51 (18) ◽

pp. 5833-5842 ◽

Cited By ~ 55

Author(s):

Sean R. Donohue ◽

Joseph H. Krushinski ◽

Victor W. Pike ◽

Eyassu Chernet ◽

Lee Phebus ◽

...

Keyword(s):

In Vivo Imaging ◽

Ex Vivo ◽

Receptor Ligands

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Supramolecular Encapsulation of Small-Ultra Red Fluorescent Proteins in Virus-Like Nanoparticles for Non-Invasive In Vivo Imaging Agents

10.26434/chemrxiv.12067851.v1 ◽

2020 ◽

Author(s):

Fabian C. Herbert ◽

Olivia Brohlin ◽

Tyler Galbraith ◽

Candace Benjamin ◽

Cesar A. Reyes ◽

...

Keyword(s):

In Vivo Imaging ◽

Fluorescent Protein ◽

Fluorescent Proteins ◽

Ex Vivo ◽

Imaging Agents ◽

Non Invasive ◽

Red Fluorescent Proteins ◽

Ex Vivo Imaging

<div> <div> <div> <p>Icosahedral virus-like particles (VLPs) derived from bacteriophages Qβ and PP7 encapsulating small-ultra red fluorescent protein (smURFP) were produced using a versatile supramolecualr capsid dissassemble-reassemble approach. The generated fluorescent VLPs display identical structural properties to their non-fluorescent analogs. Encapsulated smURFP shows indistinguishable photochemical properties to its unencapsulated counterpart, exhibits outstanding stability towards pH, and produces bright in vitro images following phagocytosis by macrophages. In vivo imaging allows biodistribution to be imaged at different time points. Ex vivo imaging of intravenously administered encapsulated smURFP reveleas localization in the liver and </p> </div> </div> <div> <div> <p>kidneys after 2 h blood circulation and substantial elimination constructs as non-invasive in vivo imaging agents. </p> </div> </div> </div>

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Uptake of Protamine Sulphate Complexed Fluorescent Nano-Particles Is Defined by Cell Cycle Status in Primary Human CD34+ Cells: Use of a Multi-Color p27 kip1 Based Flow Cytometric Assay.

Blood ◽

10.1182/blood.v106.11.1363.1363 ◽

2005 ◽

Vol 106 (11) ◽

pp. 1363-1363

Author(s):

Ryan Lahey ◽

Jesper Bonde ◽

Jan A. Nolta

Keyword(s):

Cell Cycle ◽

In Vivo Imaging ◽

Ex Vivo ◽

Nano Particles ◽

Flow Cytometry Assay ◽

Hematopoietic Stem ◽

Protamine Sulphate ◽

Flow Cytometric ◽

Cd34 Cells

Abstract The use of iron based nano-particles for multi-modal imaging is gaining interest, since it allows high resolution non-invasive in vivo imaging of human hematopoietic homing and engraftment events in xenograft models. The uptake of ferridex nano-particles complexed to cationic protamine sulphate is believed to be non-specific through mechanisms like endocytosis, but this has not been well defined for hematopoietic stem cells (HSC). In defining ex vivo cultivation strategies for manipulation of human HSC, a key factor is the responsiveness of the most primitive cells to the in vitro conditions, with the aim of maintaining viability without inducing terminal differentiation. Here, we present a novel flow cytometry assay which assesses the earliest molecular responses to a defined clinically applicable ex vivo protocol, aimed at facilitating labeling of human stem/progenitor cells using protamine sulphate complexed nano-particles for subsequent in vivo imaging. We used intracellular staining for the cell cycle inhibitor p27kip1, which is present in the highest levels in non-cycling cells, as the primary flow cytometric marker in combination with CD34, CD133 and Alexa 488, 647 and 750 conjugated ferridex nano-particles and the membrane dye PKH26. An assay was developed to simultaneously assess the molecular events occurring in individual human cord blood Lin− or CD34+ cells while they were cultured for up to 72 hours in X-Vivo 15 serum free medium supplemented with Flt3, SCF and TPO on Retronectin (RN) coated plates with or without nano-particles. Co-expression of p27kip1, CD34 or CD133 in the cultured cells slowly decreases from 86.1% CD34+p27kip1 (T=0) to 76.7%+/−12.2% (T=72) and from 89.6% CD133+p27kip1+ (T=0) to 54.1%+/−10.4% (T=72). We suggest that this slow decrease represents cells dividing and potentially differentiating over the time course of the ex vivo cultivation period. Assessing uptake of fluorescent conjugated nano-particles over a 72 hr period showed that the uptake of particles in CD34+ and CD133+ cells declined significantly after the first 24 hrs., from 32.5+/−3.7% nano-positive CD34+ cells to 19.2+/−2.9% at 48 hours ex vivo with a more significant decline to only 8.3+/−3.7% nano positive CD34+ cells in the culture after 72 hours ex vivo. The same decline in uptake over time was observed in cultured human CB cells that were positive for CD133. PKH26 co-staining demonstrated that the majority of cells that undergo cell division within the first 24 hours of ex vivo culture are the most likely to uptake the nano-particles. In summary, using a multi color p27kip1 based flow-cytometry assay, we found that human Lin−, CD133+, and CD34+ cells uptake Fe-Pro in a fashion which is not entirely cell cycle independent as previously suggested. These data indicate that cell cycle or metabolic status may influence the ability of human hematopoietic stem and progenitor subsets to uptake the protamine sulphate-complexed nano-particles. These findings emphasize the need to carefully develop ex vivo conditions for nano-particle labeling of primary human stem cells in order to perform accurate in vivo imaging of the most primitive human hematopoietic stem and progenitor cells.

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Multidimensional custom-made non-linear microscope: from ex-vivo to in-vivo imaging

Applied Physics B ◽

10.1007/s00340-008-3130-3 ◽

2008 ◽

Vol 92 (3) ◽

pp. 359-365 ◽

Cited By ~ 8

Author(s):

R. Cicchi ◽

L. Sacconi ◽

A. Jasaitis ◽

R.P. O’Connor ◽

D. Massi ◽

...

Keyword(s):

In Vivo Imaging ◽

Ex Vivo ◽

Custom Made ◽

Non Linear

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Optimized murine lung preparation for detailed structural evaluation via micro-computed tomography

Journal of Applied Physiology ◽

10.1152/japplphysiol.00550.2011 ◽

2012 ◽

Vol 112 (1) ◽

pp. 159-166 ◽

Cited By ~ 24

Author(s):

Dragoş M. Vasilescu ◽

Lars Knudsen ◽

Matthias Ochs ◽

Ewald R. Weibel ◽

Eric A. Hoffman

Keyword(s):

In Vivo Imaging ◽

Airway Pressure ◽

Ex Vivo ◽

Three Dimensional ◽

Imaging Method ◽

Small Airways ◽

Micro Computed Tomography ◽

Vascular Perfusion ◽

Murine Lung

Utilizing micro-X-ray CT (μCT) imaging, we sought to generate an atlas of in vivo and intact/ex vivo lungs from normal murine strains. In vivo imaging allows visualization of parenchymal density and small airways (15–28 μm/voxel). Ex vivo imaging of the intact lung via μCT allows for improved understanding of the three-dimensional lung architecture at the alveolar level with voxel dimensions of 1–2 μm. μCT requires that air spaces remain air-filled to detect alveolar architecture while in vivo structural geometry of the lungs is maintained. To achieve these requirements, a fixation and imaging methodology that permits nondestructive whole lung ex vivo μCT imaging has been implemented and tested. After in vivo imaging, lungs from supine anesthetized C57Bl/6 mice, at 15, 20, and 25 cmH2O airway pressure, were fixed in situ via vascular perfusion using a two-stage flushing system while held at 20 cmH2O airway pressure. Extracted fixed lungs were air-dried. Whole lung volume was acquired at 1, 7, 21, and >70 days after the lungs were dried and served as validation for fixation stability. No significant shrinkage was observed: +8.95% change from in vivo to fixed lung ( P = 0.12), −1.47% change from day 1 to day 7 ( P = 0.07), −2.51% change from day 1 to day 21 ( P = 0.05), and −4.90% change from day 1 to day 70 and thereafter ( P = 0.04). μCT evaluation showed well-fixed alveoli and capillary beds correlating with histological analysis. A fixation and imaging method has been established for μCT imaging of the murine lung that allows for ex vivo morphometric analysis, representative of the in vivo lung.

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Ex Vivo and In Vivo Imaging Study of Ultrasound Capsule Endoscopy

Journal of Medical Devices ◽

10.1115/1.4046352 ◽

2020 ◽

Vol 14 (2) ◽

Author(s):

John H. Lee ◽

Giovanni Traverso ◽

David Ibarra-Zarate ◽

Duane S. Boning ◽

Brian W. Anthony

Keyword(s):

Capsule Endoscopy ◽

In Vivo Imaging ◽

Clinical Utility ◽

Ex Vivo ◽

Imaging Study ◽

Mucosal Surface ◽

Swine Model ◽

Gi Tract ◽

Acoustic Coupling

Abstract Wireless capsule endoscopy (WCE) has revolutionized the capacity for evaluation of the gastrointestinal (GI) tract, but its evaluation is limited to the mucosal surface. To overcome this, ultrasound capsule endoscopy (UCE) that can evaluate the deeper structures beyond the mucosal surface has been proposed and several studies focusing on technology development have demonstrated promising results. However, investigations of the potential for clinical utility of this technology are lacking. This work had two main goals: perform ex vivo and in vivo imaging studies in a swine model to (1) evaluate if acoustic coupling between a capsule with a specific size and GI tract can be achieved only through peristalsis autonomously without any human control and (2) identify key issues and challenges to help guide further research. The images acquired in these studies were able to visualize the wall of the GI tract as well as the structures within demonstrating that achieving adequate acoustic coupling through peristalsis is possible. Critical challenges were identified including level of visualization and area of coverage; these require further in-depth investigation before potential clinical utility of UCE technology can be concluded.

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