SNC–Coumarin is a Biocompatible Imaging Agent for In Vivo Labeling of Cells and Fluids

Nano LIFE ◽  
2015 ◽  
Vol 05 (03) ◽  
pp. 1540004 ◽  
Author(s):  
Changliang Ren ◽  
Grace Hwee Boon Ng ◽  
Xu Li ◽  
Cathleen Teh
Keyword(s):  
In Vivo Imaging ◽  
Cell Types ◽  
The Body ◽  
Fluorescent Imaging ◽  
Imaging Agent ◽  
Fluorescent Intensity ◽  
In Vivo Detection ◽  
Fabrication Procedure ◽  
Harmful Radiation

Optical imaging uses nonionizing radiation to obtain images of tissues and cells inside the body. The approach reduces exposure to harmful radiation and is suitable for lengthy and repetitive imaging procedures. Development of strongly fluorescent imaging agents will help in the detection of signal through thick tissues. Presence of such biocompatible imaging agent has potential clinical applications as it gives real-time information on disease progression and therapeutic response. We report here a nanoformulation-based strategy to synthesize a strongly fluorescent imaging agent. The fabrication procedure uses silica nanocapsules (SNC) to trap and concentrate highly fluorescent Coumarin 545T fluorophore. Biocompatibility of synthesized SNC–Coumarin was tested in cell lines and zebrafish. In vivo detection of fluorescent signal was validated in optically translucent zebrafish larvae and adult casper mutant. Nonbiased labeling of all cell types was detected in both young and adult zebrafish. The ability to differentiate fluid filled cavities from cells was also highlighted during in vivo imaging. Concomitant assessment of internalized SNC–Coumarin through acquired fluorescent intensity and associated biocompatibility in zebrafish supports its use as an in vivo imaging agent.

Fluorescent proteins for in vivo imaging, where's the biliverdin?

2020 ◽  
Vol 48 (6) ◽  
pp. 2657-2667
Author(s):  
Felipe Montecinos-Franjola ◽  
John Y. Lin ◽  
Erik A. Rodriguez
Keyword(s):  
Hydrogen Peroxide ◽  
In Vivo Imaging ◽  
Near Infrared ◽  
Fluorescent Protein ◽  
Fluorescent Proteins ◽  
Fluorescent Imaging ◽  
Infrared Light ◽  
Red Fluorescent Protein ◽  
Color Palette

Noninvasive fluorescent imaging requires far-red and near-infrared fluorescent proteins for deeper imaging. Near-infrared light penetrates biological tissue with blood vessels due to low absorbance, scattering, and reflection of light and has a greater signal-to-noise due to less autofluorescence. Far-red and near-infrared fluorescent proteins absorb light >600 nm to expand the color palette for imaging multiple biosensors and noninvasive in vivo imaging. The ideal fluorescent proteins are bright, photobleach minimally, express well in the desired cells, do not oligomerize, and generate or incorporate exogenous fluorophores efficiently. Coral-derived red fluorescent proteins require oxygen for fluorophore formation and release two hydrogen peroxide molecules. New fluorescent proteins based on phytochrome and phycobiliproteins use biliverdin IXα as fluorophores, do not require oxygen for maturation to image anaerobic organisms and tumor core, and do not generate hydrogen peroxide. The small Ultra-Red Fluorescent Protein (smURFP) was evolved from a cyanobacterial phycobiliprotein to covalently attach biliverdin as an exogenous fluorophore. The small Ultra-Red Fluorescent Protein is biophysically as bright as the enhanced green fluorescent protein, is exceptionally photostable, used for biosensor development, and visible in living mice. Novel applications of smURFP include in vitro protein diagnostics with attomolar (10−18 M) sensitivity, encapsulation in viral particles, and fluorescent protein nanoparticles. However, the availability of biliverdin limits the fluorescence of biliverdin-attaching fluorescent proteins; hence, extra biliverdin is needed to enhance brightness. New methods for improved biliverdin bioavailability are necessary to develop improved bright far-red and near-infrared fluorescent proteins for noninvasive imaging in vivo.

Clock gene-independent daily regulation of haemoglobin oxidation in red blood cells

2021 ◽  
Author(s):  
Andrew D. Beale ◽  
Priya Crosby ◽  
Utham K. Valekunja ◽  
Rachel S. Edgar ◽  
Johanna E. Chesham ◽  
...  
Keyword(s):  
Circadian Rhythms ◽  
Red Blood Cells ◽  
Blood Cells ◽  
Human Subjects ◽  
Developmental Regulation ◽  
Physiological Role ◽  
Cell Types ◽  
The Body

AbstractCellular circadian rhythms confer daily temporal organisation upon behaviour and physiology that is fundamental to human health and disease. Rhythms are present in red blood cells (RBCs), the most abundant cell type in the body. Being naturally anucleate, RBC circadian rhythms share key elements of post-translational, but not transcriptional, regulation with other cell types. The physiological function and developmental regulation of RBC circadian rhythms is poorly understood, however, partly due to the small number of appropriate techniques available. Here, we extend the RBC circadian toolkit with a novel biochemical assay for haemoglobin oxidation status, termed “Bloody Blotting”. Our approach relies on a redox-sensitive covalent haem-haemoglobin linkage that forms during cell lysis. Formation of this linkage exhibits daily rhythms in vitro, which are unaffected by mutations that affect the timing of circadian rhythms in nucleated cells. In vivo, haemoglobin oxidation rhythms demonstrate daily variation in the oxygen-carrying and nitrite reductase capacity of the blood, and are seen in human subjects under controlled laboratory conditions as well as in freely-behaving humans. These results extend our molecular understanding of RBC circadian rhythms and suggest they serve an important physiological role in gas transport.

scholarly journals OOCHIP: Compartmentalized Microfluidic Perfusion System with Porous Barriers for Enhanced Cell–Cell Crosstalk in Organ-on-a-Chip

Micromachines ◽  
2020 ◽  
Vol 11 (6) ◽  
pp. 565
Author(s):  
Qasem Ramadan ◽  
Sajay Bhuvanendran Nair Gourikutty ◽  
Qingxin Zhang
Keyword(s):  
Drug Efficacy ◽  
Human Adipose Tissue ◽  
Cell Types ◽  
Cell Interaction ◽  
The Body ◽  
Close Proximity ◽  
Porous Barriers ◽  
Cell Cell

Improved in vitro models of human organs for predicting drug efficacy, interactions, and disease modelling are crucially needed to minimize the use of animal models, which inevitably display significant differences from the human disease state and metabolism. Inside the body, cells are organized either in direct contact or in close proximity to other cell types in a tightly controlled architecture that regulates tissue function. To emulate this cellular interface in vitro, an advanced cell culture system is required. In this paper, we describe a set of compartmentalized silicon-based microfluidic chips that enable co-culturing several types of cells in close proximity with enhanced cell–cell interaction. In vivo-like fluid flow into and/or from each compartment, as well as between adjacent compartments, is maintained by micro-engineered porous barriers. This porous structure provides a tool for mimicking the paracrine exchange between cells in the human body. As a demonstrating example, the microfluidic system was tested by culturing human adipose tissue that is infiltrated with immune cells to study the role if the interplay between the two cells in the context of type 2 diabetes. However, the system provides a platform technology for mimicking the structure and function of single- and multi-organ models, which could significantly narrow the gap between in vivo and in vitro conditions.

scholarly journals Sensitive in vivo Visualization of Breast Cancer Using Ratiometric Protease-activatable Fluorescent Imaging Agent, AVB-620

Theranostics ◽  
2017 ◽  
Vol 7 (13) ◽  
pp. 3369-3386 ◽  
Author(s):  
Marcel Miampamba ◽  
Junjie Liu ◽  
Alec Harootunian ◽  
Andrew J Gale ◽  
Stephen Baird ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Fluorescent Imaging ◽  
Imaging Agent

scholarly journals Skeletal muscle releases extracellular vesicles with distinct protein and miRNA signatures that accumulate and function within the muscle microenvironment

2021 ◽  
Author(s):  
Sho Watanabe ◽  
Yuri Sudo ◽  
Satoshi Kimura ◽  
Kenji Tomita ◽  
Makoto Noguchi ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Extracellular Vesicles ◽  
Cell Types ◽  
The Body ◽  
C2c12 Cells ◽  
Ips Cell ◽  
Potential Marker ◽  
And Function ◽  
Intercellular Communications

Extracellular vesicles (EVs) contain various regulatory molecules and mediate intercellular communications. Although EVs are secreted from various cell types, including skeletal muscle cells, and present in the blood, their identity is poorly characterized in vivo, limiting the identification of their origin in the blood. Since the skeletal muscle is the largest organ in the body, it could substantially contribute to circulating EVs as their source. However, due to the lack of defined markers that distinguish SkM-EVs from others, whether the skeletal muscle releases EVs in vivo and how much the skeletal muscle-derived EVs (SkM-EVs) account for plasma EVs remain poorly understood. In this work, we perform quantitative proteomic analyses on EVs released from C2C12 cells and human iPS cell-derived myocytes and identify potential marker proteins that mark SkM-EVs. These markers we identified apply to in vivo tracking of SkM-EVs. The results show that skeletal muscle makes only a subtle contribution to plasma EVs as their source in both control and exercise conditions in mice. On the other hand, we demonstrate that SkM-EVs are concentrated in the skeletal muscle interstitium. Furthermore, we show that interstitium EVs are highly enriched with the muscle-specific miRNAs and repress the expression of the paired box transcription factor Pax7, a master regulator for myogenesis. Taken together, our findings reveal that the skeletal muscle releases exosome-like small EVs with distinct protein and miRNA profiles in vivo and that SkM-EVs mainly play a role within the muscle microenvironment where they accumulate.

scholarly journals Graded regulation of cellular quiescence depth between proliferation and senescence by a lysosomal dimmer switch

2019 ◽  
Vol 116 (45) ◽  
pp. 22624-22634 ◽  
Author(s):  
Kotaro Fujimaki ◽  
Ruoyan Li ◽  
Hengyu Chen ◽  
Kimiko Della Croce ◽  
Hao Helen Zhang ◽  
...  
Keyword(s):  
Gene Expression ◽  
Gene Expression Signature ◽  
Cell Types ◽  
The Body ◽  
Cellular Mechanisms ◽  
Lysosomal Function ◽  
Quiescent Cells ◽  
Common Transition

The reactivation of quiescent cells to proliferate is fundamental to tissue repair and homeostasis in the body. Often referred to as the G0 state, quiescence is, however, not a uniform state but with graded depth. Shallow quiescent cells exhibit a higher tendency to revert to proliferation than deep quiescent cells, while deep quiescent cells are still fully reversible under physiological conditions, distinct from senescent cells. Cellular mechanisms underlying the control of quiescence depth and the connection between quiescence and senescence are poorly characterized, representing a missing link in our understanding of tissue homeostasis and regeneration. Here we measured transcriptome changes as rat embryonic fibroblasts moved from shallow to deep quiescence over time in the absence of growth signals. We found that lysosomal gene expression was significantly up-regulated in deep quiescence, and partially compensated for gradually reduced autophagy flux. Reducing lysosomal function drove cells progressively deeper into quiescence and eventually into a senescence-like irreversibly arrested state; increasing lysosomal function, by lowering oxidative stress, progressively pushed cells into shallower quiescence. That is, lysosomal function modulates graded quiescence depth between proliferation and senescence as a dimmer switch. Finally, we found that a gene-expression signature developed by comparing deep and shallow quiescence in fibroblasts can correctly classify a wide array of senescent and aging cell types in vitro and in vivo, suggesting that while quiescence is generally considered to protect cells from irreversible arrest of senescence, quiescence deepening likely represents a common transition path from cell proliferation to senescence, related to aging.

Image-guided surgery for tumor agnostic detection of solid tumors using the pH-activated micellar imaging agent ONM-100.

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. 3068-3068 ◽  
Author(s):  
Floris Jan Voskuil ◽  
Pieter Jan Steinkamp ◽  
Marjory Koller ◽  
Bert van der Vegt ◽  
Jan Johannes Doff ◽  
...  
Keyword(s):  
Solid Tumors ◽  
Fluorescent Imaging ◽  
Activation Mechanism ◽  
Imaging Agent ◽  
Image Guided Surgery ◽  
Pharmacokinetic Data ◽  
Guided Surgery ◽  
Image Guided ◽  
Fluorescence Images

3068 Background: ONM-100, a micelle-based polymer imaging agent conjugated to indocyanine green (ICG) and with an exquisitely pH-sensitive binary activation mechanism, may be used for tumor detection. ONM-100 micelles dissociate in acidic environments resulting in activation of the fluorescent ICG tag. As nearly all solid cancer types are acidotic, ONM-100 has the potential to act as a broadly indicated tumor agnostic imaging agent. This first-in-human study investigates the safety and feasibility of ONM-100 as a tumor agnostic imaging agent for intra-operative fluorescent imaging of various solid tumors. Methods: ONM-100 was IV administered 24±8h prior to surgery in a dose escalation scheme (0.1-1.2mg/kg). Patients with histopathologically confirmed breast cancer (BC), head and neck squamous cell carcinoma (HNSCC), colorectal cancer (CRC) and esophageal cancer (EC) were included. Blood was drawn to assess safety and pharmacokinetic data. Intra-operative fluorescence images were collected before and after tumor excision. Post-excision fluorescence images were obtained from serially sliced specimens and correlated with standard histopathological assessment. Results: 30 patients (11 BC, 13 HNSCC, 3 EC, 3 CRC) were enrolled. No ONM-100 related serious adverse events were observed and the agent was well-tolerated. A strong and sharply demarcated fluorescent signal was observed in all patients with vital tumor tissue (median CNR ranging 1.85-14.05) which correlated with tumor on final histopathology. HNSCC and superficially located BC as well as peritoneal metastasis could be clearly visualized in vivo during surgery. In four patients (BC and HNSCC), perioperatively, tumors otherwise unnoticed by the surgeons were detected on the margin or wound bed using fluorescence imaging. Additionally, two BC tumor lesions were detected that were missed by conventional pre-operative imaging and pathological assessment. Conclusions: ONM-100 appears to be safe and enables fluorescent visualization of tumors both in vivo and ex vivo. The first-in-human data demonstrate the feasibility for potential use of ONM-100 for image guided surgery, margin assessment and detection of occult disease. Clinical trial information: NTR 7085.

scholarly journals In Vivo Imaging of GLP-1R with a Targeted Bimodal PET/Fluorescence Imaging Agent

2014 ◽  
Vol 25 (7) ◽  
pp. 1323-1330 ◽  
Author(s):  
Christian Brand ◽  
Dalya Abdel-Atti ◽  
Yachao Zhang ◽  
Sean Carlin ◽  
Susan M. Clardy ◽  
...  
Keyword(s):  
Fluorescence Imaging ◽  
In Vivo Imaging ◽  
Imaging Agent

scholarly journals The Tuberculous Granuloma: An Unsuccessful Host Defence Mechanism Providing a Safety Shelter for the Bacteria?

2012 ◽  
Vol 2012 ◽  
pp. 1-14 ◽  
Author(s):  
Mayra Silva Miranda ◽  
Adrien Breiman ◽  
Sophie Allain ◽  
Florence Deknuydt ◽  
Frederic Altare
Keyword(s):  
Cell Types ◽  
Giant Cells ◽  
The Body ◽  
Differentiated Cells ◽  
Latently Infected ◽  
Long Time ◽  
Infectious Stage ◽  
Different Cell Types

One of the main features of the immune response toM. Tuberculosisis the formation of an organized structure called granuloma. It consists mainly in the recruitment at the infectious stage of macrophages, highly differentiated cells such as multinucleated giant cells, epithelioid cells and Foamy cells, all these cells being surrounded by a rim of lymphocytes. Although in the first instance the granuloma acts to constrain the infection, some bacilli can actually survive inside these structures for a long time in a dormant state. For some reasons, which are still unclear, the bacilli will reactivate in 10% of the latently infected individuals, escape the granuloma and spread throughout the body, thus giving rise to clinical disease, and are finally disseminated throughout the environment. In this review we examine the process leading to the formation of the granulomatous structures and the different cell types that have been shown to be part of this inflammatory reaction. We also discuss the differentin vivoandin vitromodels available to study this fascinating immune structure.

Sign in / Sign up

Export Citation Format

Share Document