scholarly journals Tracking Radiolabeled Endothelial Microvesicles Predicts Their Therapeutic Efficacy: A Proof-of-Concept Study in Peripheral Ischemia Mouse Model Using SPECT/CT Imaging

Pharmaceutics ◽  
2022 ◽  
Vol 14 (1) ◽  
pp. 121
Author(s):  
Romain Giraud ◽  
Anaïs Moyon ◽  
Stéphanie Simoncini ◽  
Anne-Claire Duchez ◽  
Vincent Nail ◽  
...  

Microvesicles, so-called endothelial large extracellular vesicles (LEVs), are of great interest as biological markers and cell-free biotherapies in cardiovascular and oncologic diseases. However, their therapeutic perspectives remain limited due to the lack of reliable data regarding their systemic biodistribution after intravenous administration. Methods: Applied to a mouse model of peripheral ischemia, radiolabeled endothelial LEVs were tracked and their in vivo whole-body distribution was quantified by microSPECT/CT imaging. Hindlimb perfusion was followed by LASER Doppler and motility impairment function was evaluated up to day 28 post-ischemia. Results: Early and specific homing of LEVs to ischemic hind limbs was quantified on the day of ischemia and positively correlated with reperfusion intensity at a later stage on day 28 after ischemia, associated with an improved motility function. Conclusions: This concept is a major asset for investigating the biodistribution of LEVs issued from other cell types, including cancer, thus partly contributing to better knowledge and understanding of their fate after injection.

Author(s):  
Shivangi Agarwal ◽  
Yashwanth R Sudhini ◽  
Onur K Polat ◽  
Jochen Reiser ◽  
Mehmet Mete Altintas

Kidneys, one of the vital organs in our body, are responsible for maintaining whole-body homeostasis. The complexity of renal function (e.g., filtration, reabsorption, fluid and electrolyte regulation, urine production) demands diversity not only at the level of cell types but also in their overall distribution and structural framework within the kidney. To gain an in-depth molecular-level understanding of the renal system, it is imperative to discern the components of kidney and the types of cells residing in each of the sub-regions. Recent developments in labeling, tracing, and imaging techniques enabled us to mark, monitor and identify these cells in vivo with high efficiency in a minimally invasive manner. In this review, we have summarized different cell types, specific markers that are uniquely associated with those cell types, and their distribution in kidney, which altogether make kidneys so special and different. Cellular sorting based on the presence of certain proteins on the cell surface allowed for assignment of multiple markers for each cell type. However, different studies using different techniques have found contradictions in the cell-type specific markers. Thus, the term "cell marker" might be imprecise and sub-optimal, leading to uncertainty when interpreting the data. Therefore, we strongly believe that there is an unmet need to define the best cell markers for a cell type. Although, the compendium of renal-selective marker proteins presented in this review is a resource that may be useful to the researchers, we acknowledge that the list may not be necessarily exhaustive.


Molecules ◽  
2020 ◽  
Vol 25 (15) ◽  
pp. 3553
Author(s):  
Eszter Csikós ◽  
Kata Csekő ◽  
Amir Reza Ashraf ◽  
Ágnes Kemény ◽  
László Kereskai ◽  
...  

Thyme (TO), cinnamon (CO), and Ceylon type lemongrass (LO) essential oils (EOs) are commonly used for inhalation. However, their effects and mechanisms on inflammatory processes are not well-documented, and the number of in vivo data that would be important to determine their potential benefits or risks is low. Therefore, we analyzed the chemical composition and investigated the activity of TO, CO, and LO on airway functions and inflammatory parameters in an acute pneumonitis mouse model. The components of commercially available EOs were measured by gas chromatography–mass spectrometry. Airway inflammation was induced by intratracheal endotoxin administration in mice. EOs were inhaled during the experiments. Airway function and hyperresponsiveness were determined by unrestrained whole-body plethysmography on conscious animals. Myeloperoxidase (MPO) activity was measured by spectrophotometry from lung tissue homogenates, from which semiquantitative histopathological scores were assessed. The main components of TO, CO, and LO were thymol, cinnamaldehyde, and citronellal, respectively. We provide here the first evidence that TO and CO reduce inflammatory airway hyperresponsiveness and certain cellular inflammatory parameters, so they can potentially be considered as adjuvant treatments in respiratory inflammatory conditions. In contrast, Ceylon type LO inhalation might have an irritant effect (e.g., increased airway hyperresponsiveness and MPO activity) on the inflamed airways, and therefore should be avoided.


2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Ina Weidenfeld ◽  
Christian Zakian ◽  
Peter Duewell ◽  
Andriy Chmyrov ◽  
Uwe Klemm ◽  
...  

Abstract Macrophages are one of the most functionally-diverse cell types with roles in innate immunity, homeostasis and disease making them attractive targets for diagnostics and therapy. Photo- or optoacoustics could provide non-invasive, deep tissue imaging with high resolution and allow to visualize the spatiotemporal distribution of macrophages in vivo. However, present macrophage labels focus on synthetic nanomaterials, frequently limiting their ability to combine both host cell viability and functionality with strong signal generation. Here, we present a homogentisic acid-derived pigment (HDP) for biocompatible intracellular labeling of macrophages with strong optoacoustic contrast efficient enough to resolve single cells against a strong blood background. We study pigment formation during macrophage differentiation and activation, and utilize this labeling method to track migration of pro-inflammatory macrophages in vivo with whole-body imaging. We expand the sparse palette of macrophage labels for in vivo optoacoustic imaging and facilitate research on macrophage functionality and behavior.


2020 ◽  
Author(s):  
Maria-Bernadette Madel ◽  
He Fu ◽  
Dominique D. Pierroz ◽  
Mariano Schiffrin ◽  
Carine Winkler ◽  
...  

SummaryLong bones from mammals host blood cell formation and contain multiple cell types, including adipocytes. Physiological functions of bone marrow adipocytes are poorly documented. Herein, we used adipocyte-deficient PPARγ-whole body null mice to investigate the consequence of total adipocyte deficiency on bone homeostasis in mice. We first highlight the dual bone phenotype of PPARγ null mice: on the one hand the increase bone formation and subsequent trabecularization extending in the long bone diaphysis, due to the well-known impact of PPARγ deficiency on osteoblasts formation and activity; on the other hand, an increased osteoclastogenesis in the cortical bone. We then further explore the cause of this unexpected increased osteoclastogenesis using two independent models of lipoatrophy, which recapitulated this phenotype. This demonstrates that hyperosteoclastogenesis is not intrinsically linked to PPARγ deficiency, but is a consequence of the total lipodystrophy. We further showed that adiponectin, a cytokine produced by adipocytes and mesenchymal stromal cells is a potent inhibitor of osteoclastogenesis in vitro and in vivo. Moreover, pharmacological activation of adiponectin receptors by the synthetic agonist AdipoRon inhibits mature osteoclast activity both in mouse and human cells by blocking podosome formation through AMPK activation. Finally, we demonstrated that AdipoRon treatment blocks bone erosion in vivo in a murine model of inflammatory bone loss, providing potential new approaches to treat osteoporosis.


Development ◽  
1987 ◽  
Vol 100 (1) ◽  
pp. 95-105
Author(s):  
JH Russ ◽  
JD Horton

This paper describes in vitro and in vivo attempts to deplete the 4- to 8-month-old Xenopus laevis (J strain) thymus of its lymphocyte compartment. Gamma irradiation (2-3000 rad) of the excised thymus, followed by two weeks in organ culture, is effective in removing lymphocytes, but causes drastic reduction in size and loss of normal architecture. In contrast, in vivo whole-body irradiation (3000 rad) and subsequent in situ residence for 8-14 days proves successful in providing a lymphocyte-depleted froglet thymus without loss of cortical and medullary zones. In vivo-irradiated thymuses are about half normal size, lack cortical lymphocytes, but still retain some medullary thymocytes; they show no signs of lymphocyte regeneration when subsequently organ cultured for 2 weeks. Light microscopy of 1 micron, plastic-embedded sections and electron microscopy reveal that a range of thymic stromal cell types are retained and that increased numbers of cysts, mucous and myoid cells are found in the thymus following whole-body irradiation. In vivo-irradiated thymuses are therefore suitable for implantation studies exploring the role of thymic stromal cells in tolerance induction of differentiating T lymphocytes.


2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Heather C. Rice ◽  
Gabriele Marcassa ◽  
Iordana Chrysidou ◽  
Katrien Horré ◽  
Tracy L. Young-Pearse ◽  
...  

AbstractThe amyloid-β (Aβ) peptide, the primary constituent of amyloid plaques found in Alzheimer’s disease (AD) brains, is derived from sequential proteolytic processing of the Amyloid Precursor Protein (APP). However, the contribution of different cell types to Aβ deposition has not yet been examined in an in vivo, non-overexpression system. Here, we show that endogenous APP is highly expressed in a heterogeneous subset of GABAergic interneurons throughout various laminae of the hippocampus, suggesting that these cells may have a profound contribution to AD plaque pathology. We then characterized the laminar distribution of amyloid burden in the hippocampus of an APP knock-in mouse model of AD. To examine the contribution of GABAergic interneurons to plaque pathology, we blocked Aβ production specifically in these cells using a cell type-specific knock-out of BACE1. We found that during early stages of plaque deposition, interneurons contribute to approximately 30% of the total plaque load in the hippocampus. The greatest contribution to plaque load (75%) occurs in the stratum pyramidale of CA1, where plaques in human AD cases are most prevalent and where pyramidal cell bodies and synaptic boutons from perisomatic-targeting interneurons are located. These findings reveal a crucial role of GABAergic interneurons in the pathology of AD. Our study also highlights the necessity of using APP knock-in models to correctly evaluate the cellular contribution to amyloid burden since APP overexpressing transgenic models drive expression in cell types according to the promoter and integration site and not according to physiologically relevant expression mechanisms.


2021 ◽  
pp. 153537022199305
Author(s):  
Sichi Liu ◽  
Yuyu Feng ◽  
Yonglan Huang ◽  
Xiaoling Jiang ◽  
Chengfang Tang ◽  
...  

GM1 gangliosidosis is a rare lysosomal storage disease caused by a deficiency of β-galactosidase due to mutations in the GLB1 gene. We established a C57BL/6 mouse model with Glb1G455R mutation using CRISPR/Cas9 genome editing. The β-galactosidase enzyme activity of Glb1G455R mice measured by fluorometric assay was negligible throughout the whole body. Mutant mice displayed no marked phenotype at eight weeks. After 16 weeks, GM1 ganglioside accumulation in the brain of mutant mice was observed by immunohistochemical staining. Meanwhile, a declining performance in behavioral tests was observed among mutant mice from 16 to 32 weeks. As the disease progressed, the neurological symptoms of mutant mice worsened, and they then succumbed to the disease by 47 weeks of age. We also observed microglia activation and proliferation in the cerebral cortex of mutant mice at 16 and 32 weeks. In these activated microglia, the level of autophagy regulator LC3 was up-regulated but the mRNA level of LC3 was normal. In conclusion, we developed a novel murine model that mimicked the chronic phenotype of human GM1. This Glb1G455R murine model is a practical in vivo model for studying the pathogenesis of GM1 gangliosidosis and exploring potential therapies.


Biomolecules ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1532
Author(s):  
M. Dolores Molina ◽  
Francesc Cebrià

Planarians are flatworms capable of whole-body regeneration, able to regrow any missing body part after injury or amputation. The extraordinary regenerative capacity of planarians is based upon the presence in the adult of a large population of somatic pluripotent stem cells. These cells, called neoblasts, offer a unique system to study the process of stem cell specification and differentiation in vivo. In recent years, FACS-based isolation of neoblasts, RNAi functional analyses as well as high-throughput approaches such as single-cell sequencing have allowed a rapid progress in our understanding of many different aspects of neoblast biology. Here, we summarize our current knowledge on the molecular signatures that define planarian neoblasts heterogeneity, which includes a percentage of truly pluripotent stem cells, and guide the commitment of pluripotent neoblasts into lineage-specific progenitor cells, as well as their differentiation into specific planarian cell types.


2019 ◽  
Author(s):  
Zheng Han ◽  
Senquan Liu ◽  
Yigang Pei ◽  
Zheng Ding ◽  
Yuguo Li ◽  
...  

AbstractHuman stem-cell-derived extracellular vesicles (EVs) are currently being investigated for cell-free therapy in regenerative medicine applications, but their biodistribution and tropic properties for homing to injured tissues are largely unknown. Here, we labeled EVs with magnetic nanoparticles to create magneto-EVs that can be tracked by magnetic resonance imaging (MRI). Superparamagnetic iron oxide (SPIO) nanoparticles were coated with polyhistidine tags, which enabled purification of labeled EVs by efficiently removing unencapsulated SPIO particles in the solution. The biodistribution of systemically injected human induced pluripotent stem cell (iPSC)-derived magneto-EV was assessed in three different animal models of kidney injury and myocardial ischemia. Magneto-EVs were found to selectively home to the injury sites and conferred substantial protection in a kidney injury model. In vivo MRI tracking of magnetically labeled EVs represents a new powerful method to assess and quantify their whole-body distribution, which may help optimize further development of EV-based cell-free therapy.


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