135 results on '"Avnesh S. Thakor"'
Search Results
2. Time-course analysis of cisplatin induced AKI in preclinical models: implications for testing different sources of MSCs
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Abantika Ganguly, Shashank Chetty, Rosita Primavera, Steven Levitte, Shobha Regmi, Benjamin William Dulken, Scott M. Sutherland, Wendy Angeles, Jing Wang, and Avnesh S. Thakor
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Acute kidney injury ,Cisplatin ,Mesenchymal Stem Cells ,Cell therapy ,Transcriptomics ,Temporal profile ,Medicine - Abstract
Abstract Background Kidneys are at risk from drug-induced toxicity, with a significant proportion of acute kidney injury (AKI) linked to medications, particularly cisplatin. Existing cytoprotective drugs for cisplatin-AKI carry side effects, prompting a search for better biological therapies. Mesenchymal Stem Cells (MSCs) are under consideration given their regenerative properties, yet their clinical application has not achieved their full potential, mainly due to variability in the source of MSC tested. In addition, translating treatments from rodent models to humans remains challenging due to a lack of standardized dosing and understanding potential differential responses to cisplatin between animal strains. Method In the current study, we performed a time-course analysis of the effect of cisplatin across different mouse strains and evaluated gender related differences to create a robust preclinical model that could then be used to explore the therapeutic efficacy of different sources of MSCs for their ability to reverse AKI. Result Our data indicated that different mouse strains produce differential responses to the same cisplatin dosing regimen. Despite this, we did not observe any gender-related bias towards cisplatin nephrotoxicity. Furthermore, our time-course analysis identified that cisplatin-induced inflammation was driven by a strong CXCL1 response, which was used as a putative biomarker to evaluate the comparative therapeutic efficacy of different MSC sources in reversing AKI. Our data indicates that UC-MSCs have a stronger anti-inflammatory effect compared to BM-MSCs and AD-MSCs, which helped to ameliorate cisplatin-AKI. Conclusion Overall, our data underscores the importance of using an optimized preclinical model of cisplatin-AKI to test different therapies. We identified CXCL1 as a potential biomarker of cisplatin-AKI and identified the superior efficacy of UC-MSCs in mitigating cisplatin-AKI. Graphical abstract
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- 2024
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3. Therapeutic potential of exosomes derived from mesenchymal stem cells for treatment of systemic lupus erythematosus
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Shima Famil Samavati, Reza Yarani, Sara Kiani, Zohreh HoseinKhani, Masomeh Mehrabi, Steven Levitte, Rosita Primavera, Shashank Chetty, Avnesh S. Thakor, and Kamran Mansouri
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Therapeutics. Pharmacology ,RM1-950 - Abstract
Abstract Autoimmune diseases are caused by an imbalance in the immune system, producing autoantibodies that cause inflammation leading to tissue damage and organ dysfunction. Systemic Lupus Erythematosus (SLE) is one of the most common autoimmune diseases and a major contributor to patient morbidity and mortality. Although many drugs manage the disease, curative therapy remains elusive, and current treatment regimens have substantial side effects. Recently, the therapeutic potential of exosomes has been extensively studied, and novel evidence has been demonstrated. A direct relationship between exosome contents and their ability to regulate the immune system, inflammation, and angiogenesis. The unique properties of extracellular vesicles, such as biomolecule transportation, biodegradability, and stability, make exosomes a promising treatment candidate for autoimmune diseases, particularly SLE. This review summarizes the structural features of exosomes, the isolation/purification/quantification method, their origin, effect, immune regulation, a critical consideration for selecting an appropriate source, and their therapeutic mechanisms in SLE.
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- 2024
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4. Integrated transcriptome-proteome analyses of human stem cells reveal source-dependent differences in their regenerative signature
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Abantika Ganguly, Ganesh Swaminathan, Fernando Garcia-Marques, Shobha Regmi, Reza Yarani, Rosita Primavera, Shashank Chetty, Abel Bermudez, Sharon J. Pitteri, and Avnesh S. Thakor
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transcriptomics ,proteomics ,secretome ,integrative ,multi-omics ,mesenchymal stem cell ,Medicine (General) ,R5-920 ,Biology (General) ,QH301-705.5 - Abstract
Summary: Mesenchymal stem cells (MSCs) are gaining increasing prominence as an effective regenerative cellular therapy. However, ensuring consistent and reliable effects across clinical populations has proved to be challenging. In part, this can be attributed to heterogeneity in the intrinsic molecular and regenerative signature of MSCs, which is dependent on their source of origin. The present work uses integrated omics-based profiling, at different functional levels, to compare the anti-inflammatory, immunomodulatory, and angiogenic properties between MSCs from neonatal (umbilical cord MSC [UC-MSC]) and adult (adipose tissue MSC [AD-MSC], and bone marrow MSC [BM-MSC]) sources. Using multi-parametric analyses, we identified that UC-MSCs promote a more robust host innate immune response; in contrast, adult-MSCs appear to facilitate remodeling of the extracellular matrix (ECM) with stronger activation of angiogenic cascades. These data should help facilitate the standardization of source-specific MSCs, such that their regenerative signatures can be confidently used to target specific disease processes.
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- 2023
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5. Mesenchymal stromal cells for the treatment of Alzheimer’s disease: Strategies and limitations
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Shobha Regmi, Daniel Dan Liu, Michelle Shen, Bhavesh D. Kevadiya, Abantika Ganguly, Rosita Primavera, Shashank Chetty, Reza Yarani, and Avnesh S. Thakor
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mesenchymal stromal cells ,mesenchymal stem cells ,Alzheimer’s disease ,microglia ,neurons ,neuroprotection ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Alzheimer’s disease (AD) is a major cause of age-related dementia and is characterized by progressive brain damage that gradually destroys memory and the ability to learn, which ultimately leads to the decline of a patient’s ability to perform daily activities. Although some of the pharmacological treatments of AD are available for symptomatic relief, they are not able to limit the progression of AD and have several side effects. Mesenchymal stem/stromal cells (MSCs) could be a potential therapeutic option for treating AD due to their immunomodulatory, anti-inflammatory, regenerative, antioxidant, anti-apoptotic, and neuroprotective effects. MSCs not only secret neuroprotective and anti-inflammatory factors to promote the survival of neurons, but they also transfer functional mitochondria and miRNAs to boost their bioenergetic profile as well as improve microglial clearance of accumulated protein aggregates. This review focuses on different clinical and preclinical studies using MSC as a therapy for treating AD, their outcomes, limitations and the strategies to potentiate their clinical translation.
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- 2022
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6. Correction: Facilitating islet transplantation using a three-step approach with mesenchymal stem cells, encapsulation, and pulsed focused ultrasound
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Mehdi Razavi, Tanchen Ren, Fengyang Zheng, Arsenii Telichko, Jing Wang, Jeremy J. Dahl, Utkan Demirci, and Avnesh S. Thakor
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Medicine (General) ,R5-920 ,Biochemistry ,QD415-436 - Published
- 2022
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7. Human adipose tissue-derived mesenchymal stem cells and their extracellular vesicles modulate lipopolysaccharide activated human microglia
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Marta Garcia-Contreras and Avnesh S. Thakor
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 ,Cytology ,QH573-671 - Abstract
Abstract Neurodegenerative diseases (NDs), such as Alzheimer’s disease (AD), are driven by neuroinflammation triggered by activated microglial cells; hence, the phenotypic regulation of these cells is an appealing target for intervention. Human adipose tissue-derived mesenchymal stem cells (hAD-MSCs) may be a potential therapeutic candidate to treat NDs given their immunomodulatory properties. Evidence suggests that the mechanism of action of hAD-MSCs is through their secretome, which includes secreted factors such as cytokines, chemokines, or growth factors as well as extracellular vesicles (EVs). Recently, EVs have emerged as important mediators in cell communication given, they can transfer proteins, lipids, and RNA species (i.e., miRNA, mRNA, and tRNAs) to modulate recipient cells. However, the therapeutic potential of hAD-MSCs and their secreted EVs has not been fully elucidated with respect to human microglia. In this study, we determined the therapeutic potential of different hAD-MSCs doses (200,000, 100,000, and 50,000 cells) or their secreted EVs (50, 20, or 10 µg/ml), on human microglial cells (HMC3) that were activated by lipopolysaccharides (LPS). Upregulation of inducible nitric oxide synthase (iNOS), an activation marker of HMC3 cells, was prevented when they were cocultured with hAD-MSCs and EVs. Moreover, hAD-MSCs inhibited the secretion of proinflammatory factors, such as IL-6, IL-8, and MCP-1, while their secreted EVs promoted the expression of anti-inflammatory mediators such as IL-10 or TIMP-1 in activated microglia. The present data therefore support a role for hAD-MSCs and their secreted EVs, as potential therapeutic candidates for the treatment of NDs.
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- 2021
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8. Blood Oxygen Level-Dependent (BOLD) MRI in Glomerular Disease
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Daniel R. Nemirovsky, Puneet Gupta, Sophia Hu, Raymond Wong, and Avnesh S. Thakor
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BOLD MRI ,glomerular ,hypoxia ,nephrotic ,nephritic ,Surgery ,RD1-811 - Abstract
Renal hypoxia has recently been implicated as a key contributor and indicator of various glomerular diseases. As such, monitoring changes in renal oxygenation in these disorders may provide an early diagnostic advantage that could prevent potential adverse outcomes. Blood oxygen level-dependent magnetic resonance imaging (BOLD MRI) is an emerging noninvasive technique for assessing renal oxygenation in glomerular disease. Although BOLD MRI has produced promising initial results for the use in certain renal pathologies, the use of BOLD imaging in glomerular diseases, including primary and secondary nephrotic and nephritic syndromes, is relatively unexplored. Early BOLD studies on primary nephrotic syndrome, nephrotic syndrome secondary to diabetes mellitus, and nephritic syndrome secondary to systemic lupus erythematosus have shown promising results to support its future clinical utility. In this review, we outline the advancements made in understanding the use of BOLD MRI for the assessment, diagnosis, and screening of these pathologies.
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- 2021
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9. β Cell and Autophagy: What Do We Know?
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Hamid-Reza Mohammadi-Motlagh, Mona Sadeghalvad, Niloofar Yavari, Rosita Primavera, Setareh Soltani, Shashank Chetty, Abantika Ganguly, Shobha Regmi, Tina Fløyel, Simranjeet Kaur, Aashiq H. Mirza, Avnesh S. Thakor, Flemming Pociot, and Reza Yarani
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β cell ,autophagy ,insulin homeostasis ,autophagy modulators ,type 1 diabetes ,type 2 diabetes ,Microbiology ,QR1-502 - Abstract
Pancreatic β cells are central to glycemic regulation through insulin production. Studies show autophagy as an essential process in β cell function and fate. Autophagy is a catabolic cellular process that regulates cell homeostasis by recycling surplus or damaged cell components. Impaired autophagy results in β cell loss of function and apoptosis and, as a result, diabetes initiation and progress. It has been shown that in response to endoplasmic reticulum stress, inflammation, and high metabolic demands, autophagy affects β cell function, insulin synthesis, and secretion. This review highlights recent evidence regarding how autophagy can affect β cells’ fate in the pathogenesis of diabetes. Furthermore, we discuss the role of important intrinsic and extrinsic autophagy modulators, which can lead to β cell failure.
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- 2023
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10. Pulsed focused ultrasound enhances the therapeutic effect of mesenchymal stromal cell-derived extracellular vesicles in acute kidney injury
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Mujib Ullah, Daniel D. Liu, Sravanthi Rai, Mehdi Razavi, Waldo Concepcion, and Avnesh S. Thakor
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Extracellular vesicles ,Mesenchymal stromal cells ,Acute kidney injury ,Focused ultrasound ,Regenerative medicine ,Homing ,Medicine (General) ,R5-920 ,Biochemistry ,QD415-436 - Abstract
Abstract Background Acute kidney injury (AKI) is characterized by rapid failure of renal function and has no curative therapies. Mesenchymal stromal cell (MSC)-derived extracellular vesicles (EVs) are known to carry therapeutic factors, which have shown promise in regenerative medicine applications, including AKI. However, there remains an unmet need to optimize their therapeutic effect. One potential avenue of optimization lies in pulsed focused ultrasound (pFUS), where tissues-of-interest are treated with sound waves. pFUS has been shown to enhance MSC therapy via increased cell homing, but its effects on cell-free EV therapy remain largely unexplored. Methods We combine pFUS pretreatment of the kidney with MSC-derived EV therapy in a mouse model of cisplatin-induced AKI. Results EVs significantly improved kidney function, reduced injury markers, mediated increased proliferation, and reduced inflammation and apoptosis. While pFUS did not enhance EV homing to the kidney, the combined treatment resulted in a superior therapeutic effect compared to either treatment alone. We identified several molecular mechanisms underlying this synergistic therapeutic effect, including upregulation of proliferative signaling (MAPK/ERK, PI3K/Akt) and regenerative pathways (eNOS, SIRT3), as well as suppression of inflammation. Conclusion Taken together, pFUS may be a strategy for enhancing the therapeutic efficacy of MSC-derived EV treatment for the treatment of AKI.
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- 2020
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11. Facilitating islet transplantation using a three-step approach with mesenchymal stem cells, encapsulation, and pulsed focused ultrasound
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Mehdi Razavi, Tanchen Ren, Fengyang Zheng, Arsenii Telichko, Jing Wang, Jeremy J. Dahl, Utkan Demirci, and Avnesh S. Thakor
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Islets transplantation ,Mesenchymal stem cells ,Encapsulation ,Pulsed focused ultrasound ,Diabetes ,Medicine (General) ,R5-920 ,Biochemistry ,QD415-436 - Abstract
Abstract Background The aim of this study was to examine the effect of a three-step approach that utilizes the application of adipose tissue-derived mesenchymal stem cells (AD-MSCs), encapsulation, and pulsed focused ultrasound (pFUS) to help the engraftment and function of transplanted islets. Methods In step 1, islets were co-cultured with AD-MSCs to form a coating of AD-MSCs on islets: here, AD-MSCs had a cytoprotective effect on islets; in step 2, islets coated with AD-MSCs were conformally encapsulated in a thin layer of alginate using a co-axial air-flow method: here, the capsule enabled AD-MSCs to be in close proximity to islets; in step 3, encapsulated islets coated with AD-MSCs were treated with pFUS: here, pFUS enhanced the secretion of insulin from islets as well as stimulated the cytoprotective effect of AD-MSCs. Results Our approach was shown to prevent islet death and preserve islet functionality in vitro. When 175 syngeneic encapsulated islets coated with AD-MSCs were transplanted beneath the kidney capsule of diabetic mice, and then followed every 3 days with pFUS treatment until day 12 post-transplantation, we saw a significant improvement in islet function with diabetic animals re-establishing glycemic control over the course of our study (i.e., 30 days). In addition, our approach was able to enhance islet engraftment by facilitating their revascularization and reducing inflammation. Conclusions This study demonstrates that our clinically translatable three-step approach is able to improve the function and viability of transplanted islets.
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- 2020
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12. The role of ultrasound in enhancing mesenchymal stromal cell‐based therapies
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Daniel D. Liu, Mujib Ullah, Waldo Concepcion, Jeremy J. Dahl, and Avnesh S. Thakor
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cell therapy ,extracorporeal shockwave therapy ,focused ultrasound ,homing ,low‐intensity ultrasound ,mesenchymal stromal cells ,Medicine (General) ,R5-920 ,Cytology ,QH573-671 - Abstract
Abstract Mesenchymal stromal cells (MSCs) have been a popular platform for cell‐based therapy in regenerative medicine due to their propensity to home to damaged tissue and act as a repository of regenerative molecules that can promote tissue repair and exert immunomodulatory effects. Accordingly, a great deal of research has gone into optimizing MSC homing and increasing their secretion of therapeutic molecules. A variety of methods have been used to these ends, but one emerging technique gaining significant interest is the use of ultrasound. Sound waves exert mechanical pressure on cells, activating mechano‐transduction pathways and altering gene expression. Ultrasound has been applied both to cultured MSCs to modulate self‐renewal and differentiation, and to tissues‐of‐interest to make them a more attractive target for MSC homing. Here, we review the various applications of ultrasound to MSC‐based therapies, including low‐intensity pulsed ultrasound, pulsed focused ultrasound, and extracorporeal shockwave therapy, as well as the use of adjunctive therapies such as microbubbles. At a molecular level, it seems that ultrasound transiently generates a local gradient of cytokines, growth factors, and adhesion molecules that facilitate MSC homing. However, the molecular mechanisms underlying these methods are far from fully elucidated and may differ depending on the ultrasound parameters. We thus put forth minimal criteria for ultrasound parameter reporting, in order to ensure reproducibility of studies in the field. A deeper understanding of these mechanisms will enhance our ability to optimize this promising therapy to assist MSC‐based approaches in regenerative medicine.
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- 2020
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13. Reversing Acute Kidney Injury Using Pulsed Focused Ultrasound and MSC Therapy: A Role for HSP-Mediated PI3K/AKT Signaling
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Mujib Ullah, Daniel D. Liu, Sravanthi Rai, Arya Dadhania, Sriya Jonnakuti, Waldo Concepcion, and Avnesh S. Thakor
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acute kidney injury ,heat shock protein ,kidney regeneration ,focused ultrasound ,mesenchymal stromal cell ,signaling ,Genetics ,QH426-470 ,Cytology ,QH573-671 - Abstract
Acute kidney injury (AKI) is characterized by a sudden failure of renal function, but despite increasing worldwide prevalence, current treatments are largely supportive, with no curative therapies. Mesenchymal stromal cell (MSC) therapy has been shown to have a promising regenerative effect in AKI but is limited by the ability of cells to home to damaged tissue. Pulsed focused ultrasound (pFUS), wherein target tissues are sonicated by short bursts of sound waves, has been reported to enhance MSC homing by upregulating local homing signals. However, the exact mechanism by which pFUS enhances MSC therapy remains insufficiently explored. In this study, we studied the effect of bone marrow-derived MSCs (BM-MSCs), in conjunction with pFUS, in a mouse model of cisplatin-induced AKI. Here, BM-MSCs improved kidney function, reduced histological markers of kidney injury, decreased inflammation and apoptosis, and promoted cellular proliferation. Surprisingly, whereas pFUS did not upregulate local cytokine expression or improve BM-MSC homing, it did potentiate the effect of MSC treatment in AKI. Further analysis linked this effect to the upregulation of heat shock protein (HSP)20/HSP40 and subsequent phosphatidylinositol 3-kinase (PI3K)/Akt signaling. In summary, our results suggest that pFUS and BM-MSCs have independent as well as synergistic therapeutic effects in the context of AKI.
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- 2020
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14. Stem cell-derived extracellular vesicles: role in oncogenic processes, bioengineering potential, and technical challenges
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Mujib Ullah, Yang Qiao, Waldo Concepcion, and Avnesh S. Thakor
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Stem cells ,Extracellular vesicles ,Cancer ,Inflammation ,Immunology ,Repair ,Medicine (General) ,R5-920 ,Biochemistry ,QD415-436 - Abstract
Abstract Extracellular vesicles (EVs) are cellular-derived versatile transporters with a specialized property for trafficking a variety of cargo, including metabolites, growth factors, cytokines, proteins, lipids, and nucleic acids, throughout the microenvironment. EVs can act in a paracrine manner to facilitate communication between cells as well as modulate immune, inflammatory, regenerative, and remodeling processes. Of particular interest is the emerging association between EVs and stem cells, given their ability to integrate complex inputs for facilitating cellular migration to the sites of tissue injury. Additionally, stem cell-derived EVs can also act in an autocrine manner to influence stem cell proliferation, mobilization, differentiation, and self-renewal. Hence, it has been postulated that stem cells and EVs may work synergistically in the process of tissue repair and that dysregulation of EVs may cause a loss of homeostasis in the microenvironment leading to disease. By harnessing the property of EVs for delivery of small molecules, stem cell-derived EVs possess significant potential as a platform for developing bioengineering approaches for next-generation cancer therapies and targeted drug delivery methods. Although one of the main challenges of clinical cancer treatment remains a lack of specificity for the delivery of effective treatment options, EVs can be modified via genetic, biochemical, or synthetic methods for enhanced targeting ability of chemotherapeutic agents in promoting tumor regression. Here, we summarize recent research on the bioengineering potential of EV-based cancer therapies. A comprehensive understanding of EV modification may provide a novel strategy for cancer therapy and for the utilization of EVs in the targeting of oncogenic processes. Furthermore, innovative and emerging new technologies are shifting the paradigm and playing pivotal roles by continually expanding novel methods and materials for synthetic processes involved in the bioengineering of EVs for enhanced precision therapeutics.
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- 2019
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15. Mesenchymal Stromal Cell Homing: Mechanisms and Strategies for Improvement
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Mujib Ullah, Daniel D. Liu, and Avnesh S. Thakor
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Science - Abstract
Mesenchymal stromal cells (MSCs) have been widely investigated for their therapeutic potential in regenerative medicine, owing to their ability to home damaged tissue and serve as a reservoir of growth factors and regenerative molecules. As such, clinical applications of MSCs are reliant on these cells successfully migrating to the desired tissue following their administration. Unfortunately, MSC homing is inefficient, with only a small percentage of cells reaching the target tissue following systemic administration. This attrition represents a major bottleneck in realizing the full therapeutic potential of MSC-based therapies. Accordingly, a variety of strategies have been employed in the hope of improving this process. Here, we review the molecular mechanisms underlying MSC homing, based on a multistep model involving (1) initial tethering by selectins, (2) activation by cytokines, (3) arrest by integrins, (4) diapedesis or transmigration using matrix remodelers, and (5) extravascular migration toward chemokine gradients. We then review the various strategies that have been investigated for improving MSC homing, including genetic modification, cell surface engineering, in vitro priming of MSCs, and in particular, ultrasound techniques, which have recently gained significant interest. Contextualizing these strategies within the multistep homing model emphasizes that our ability to optimize this process hinges on our understanding of its molecular mechanisms. Moving forward, it is only with a combined effort of basic biology and translational work that the potential of MSC-based therapies can be realized. : Biological Sciences; Cell Biology; Stem Cells Research Subject Areas: Biological Sciences, Cell Biology, Stem Cells Research
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- 2019
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16. The Paracrine Function of Mesenchymal Stem Cells in Response to Pulsed Focused Ultrasound
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Mehdi Razavi, Melika Rezaee, Arsenii Telichko, Hakan Inan, Jeremy Dahl, Utkan Demirci, and Avnesh S. Thakor
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Medicine - Abstract
We studied the paracrine function of mesenchymal stem cells (MSCs) derived from various sources in response to pulsed focused ultrasound (pFUS). Human adipose tissue (AD), bone marrow (BM), and umbilical cord (UC) derived MSCs were exposed to pFUS at two intensities: 0.45 W/cm 2 I SATA (310 kPa PNP) and 1.3 W/cm 2 I SATA (540 kPa PNP). Following pFUS, the viability and proliferation of MSCs were assessed using a hemocytometer and confocal microscopy, and their secreted cytokine profile determined using a multiplex ELISA. Our findings showed that pFUS can stimulate the production of immunomodulatory, anti-inflammatory, and angiogenic cytokines from MSCs which was dependent on both the source of MSC being studied and the acoustic intensity employed. These important findings set the foundation for additional mechanistic and validation studies using this novel noninvasive and clinically translatable technology for modulating MSC biology.
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- 2020
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17. Loop-Mediated Isothermal Amplification (LAMP): A Rapid, Sensitive, Specific, and Cost-Effective Point-of-Care Test for Coronaviruses in the Context of COVID-19 Pandemic
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Robin Augustine, Anwarul Hasan, Suvarthi Das, Rashid Ahmed, Yasuyoshi Mori, Tsugunori Notomi, Bhavesh D. Kevadiya, and Avnesh S. Thakor
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point-of-care tests ,COVID-19 ,coronavirus ,SARS-CoV-2 ,LAMP ,RT-LAMP ,Biology (General) ,QH301-705.5 - Abstract
The rampant spread of COVID-19 and the worldwide prevalence of infected cases demand a rapid, simple, and cost-effective Point of Care Test (PoCT) for the accurate diagnosis of this pandemic. The most common molecular tests approved by regulatory bodies across the world for COVID-19 diagnosis are based on Polymerase Chain Reaction (PCR). While PCR-based tests are highly sensitive, specific, and remarkably reliable, they have many limitations ranging from the requirement of sophisticated laboratories, need of skilled personnel, use of complex protocol, long wait times for results, and an overall high cost per test. These limitations have inspired researchers to search for alternative diagnostic methods that are fast, economical, and executable in low-resource laboratory settings. The discovery of Loop-mediated isothermal Amplification (LAMP) has provided a reliable substitute platform for the accurate detection of low copy number nucleic acids in the diagnosis of several viral diseases, including epidemics like Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS). At present, a cocktail of LAMP assay reagents along with reverse transcriptase enzyme (Reverse Transcription LAMP, RT-LAMP) can be a robust solution for the rapid and cost-effective diagnosis for COVID-19, particularly in developing, and low-income countries. In summary, the development of RT-LAMP based diagnostic tools in a paper/strip format or the integration of this method into a microfluidic platform such as a Lab-on-a-chip may revolutionize the concept of PoCT for COVID-19 diagnosis. This review discusses the principle, technology and past research underpinning the success for using this method for diagnosing MERS and SARS, in addition to ongoing research, and the prominent prospect of RT-LAMP in the context of COVID-19 diagnosis.
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- 2020
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18. A Novel Approach to Deliver Therapeutic Extracellular Vesicles Directly into the Mouse Kidney via Its Arterial Blood Supply
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Mujib Ullah, Daniel D. Liu, Sravanthi Rai, Mehdi Razavi, Jeff Choi, Jing Wang, Waldo Concepcion, and Avnesh S. Thakor
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locoregional delivery ,intra-arterial delivery ,targeted therapy ,microsurgery ,acute kidney injury ,mesenchymal stromal cells ,Cytology ,QH573-671 - Abstract
Diseases of the kidney contribute a significant morbidity and mortality burden on society. Localized delivery of therapeutics directly into the kidney, via its arterial blood supply, has the potential to enhance their therapeutic efficacy while limiting side effects associated with conventional systemic delivery. Targeted delivery in humans is feasible given that we can access the renal arterial blood supply using minimally invasive endovascular techniques and imaging guidance. However, there is currently no described way to reproduce or mimic this approach in a small animal model. Here, we develop in mice a reproducible microsurgical technique for the delivery of therapeutics directly into each kidney, via its arterial blood supply. Using our technique, intra-arterially (IA) injected tattoo dye homogenously stained both kidneys, without staining any other organ. Survival studies showed no resulting mortality or iatrogenic kidney injury. We demonstrate the therapeutic potential of our technique in a mouse model of cisplatin-induced acute kidney injury (AKI). IA injection of mesenchymal stromal cell (MSC)-derived extracellular vesicles (EVs) successfully reversed AKI, with reduced physiological and molecular markers of kidney injury, attenuated inflammation, and restoration of proliferation and regeneration markers. This reproducible delivery technique will allow for further pre-clinical translational studies investigating other therapies for the treatment of renal pathologies.
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- 2020
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19. Reversal of Hyperglycemia and Suppression of Type 1 Diabetes in the NOD Mouse with Apoptotic DNA Immunotherapy™ (ADi™), ADi-100
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David G. Alleva, Melika Rezaee, Linda Yip, Gang Ren, Jarrett Rosenberg, Waldo Concepcion, Alan Escher, Shahrokh Shabahang, and Avnesh S. Thakor
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diabetes ,immunotherapy ,hyperglycemia ,dna immunotherapy ,nod mouse ,type 1 diabetes ,antigen-specific ,dna plasmids ,adi-100 ,monotherapy ,apoptosis ,bax ,t cells ,sgad55 ,pre-diabetic mouse ,Biology (General) ,QH301-705.5 - Abstract
The antigen-specific apoptotic DNA immunotherapeutic, ADi-100, is designed to suppress type 1 diabetes and consists of two DNA plasmids encoding genetic sequences of the apoptosis-inducing molecule, BAX, and the secreted form of the autoantigen, glutamic acid decarboxylase 65, that is CpG hyper-methylated to avoid inflammatory signaling (msGAD55). Upon a four-day treatment with ADi-100 of young female non-obese diabetic (NOD) mice, the frequency of various tolerogenic dendritic cell populations increased in draining lymph nodes; these cells lost the capacity to stimulate glutamic acid decarboxylase (GAD)-specific CD4+ T lymphocytes and were associated with the previously demonstrated enhancement of GAD-specific regulatory T cells. The efficacy of two ADi-100 formulations containing different proportions of BAX and msGAD55, 1:4 (10/40 µg) and 1:2 (17/33 µg), was evaluated in mildly hyperglycemic pre-diabetic NOD female mice. Both formulations suppressed the incidence of diabetes by 80% in an antigen-specific manner, while all untreated mice developed diabetes. However, treatment of pre-diabetic mice with significantly higher hyperglycemia, denoting progressive disease, showed that ADi-100 1:2 strongly suppressed diabetes incidence by 80% whereas the ADi-100 1:4 was less effective (50%). As an antigen-specific monotherapy, ADi-100 is highly efficacious in reversing elevated hyperglycemia to prevent diabetes, in which increasing apoptosis-inducing BAX content is a promising immune tolerance feature.
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- 2020
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20. Low-count whole-body PET/MRI restoration: an evaluation of dose reduction spectrum and five state-of-the-art artificial intelligence models
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Yan-Ran Wang, Pengcheng Wang, Lisa Christine Adams, Natasha Diba Sheybani, Liangqiong Qu, Amir Hossein Sarrami, Ashok Joseph Theruvath, Sergios Gatidis, Tina Ho, Quan Zhou, Allison Pribnow, Avnesh S. Thakor, Daniel Rubin, and Heike E. Daldrup-Link
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Radiology, Nuclear Medicine and imaging ,General Medicine - Published
- 2023
21. Fetal Cardiovascular Physiology
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Dino A. Giussani, Kimberley J. Botting, Youguo Niu, Caroline J. Shaw, Sage G. Ford, and Avnesh S. Thakor
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- 2023
22. β Cell and Autophagy:What Do We Know?
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Hamid-Reza Mohammadi-Motlagh, Mona Sadeghalvad, Niloofar Yavari, Rosita Primavera, Setareh Soltani, Shashank Chetty, Abantika Ganguly, Shobha Regmi, Tina Fløyel, Simranjeet Kaur, Aashiq H. Mirza, Avnesh S. Thakor, Flemming Pociot, and Reza Yarani
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autophagy ,type 1 diabetes ,β cell ,type 2 diabetes ,autophagy modulators ,Molecular Biology ,Biochemistry ,insulin homeostasis - Abstract
Pancreatic β cells are central to glycemic regulation through insulin production. Studies show autophagy as an essential process in β cell function and fate. Autophagy is a catabolic cellular process that regulates cell homeostasis by recycling surplus or damaged cell components. Impaired autophagy results in β cell loss of function and apoptosis and, as a result, diabetes initiation and progress. It has been shown that in response to endoplasmic reticulum stress, inflammation, and high metabolic demands, autophagy affects β cell function, insulin synthesis, and secretion. This review highlights recent evidence regarding how autophagy can affect β cells’ fate in the pathogenesis of diabetes. Furthermore, we discuss the role of important intrinsic and extrinsic autophagy modulators, which can lead to β cell failure.
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- 2023
23. Human placental mesenchymal stromal cell‐derived exosome‐enriched extracellular vesicles for chronic cutaneous graft‐versus‐host disease: A case report
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Amir Hossein Norooznezhad, Reza Yarani, Mehrdad Payandeh, Zohreh Hoseinkhani, Sarah Kiani, Elham Taghizadeh, Avnesh S. Thakor, and Kamran Mansouri
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graft‐versus‐host disease ,Placenta ,Short Communication ,Short Communications ,Graft vs Host Disease ,Mesenchymal Stem Cells ,Cell Biology ,Exosomes ,Mesenchymal Stem Cell Transplantation ,Extracellular Vesicles ,Pregnancy ,cutaneous GVHD ,human mesenchymal stromal cell ,Humans ,exosome ,Molecular Medicine ,Female - Published
- 2021
24. Endogenous NO-releasing Carbon Nanodots for Tumor-specific Gas Therapy
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Xue Liu, Qian Xu, Qiuhua Wu, Yang Wu, Cheng Jiamin, Yulin Liu, Bhavesh D. Kevadiya, Manling Chen, Yang Li, Guolin Zhang, and Avnesh S. Thakor
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Male ,Cell ,Biomedical Engineering ,Nitric Oxide ,Biochemistry ,Nitric oxide ,Biomaterials ,chemistry.chemical_compound ,In vivo ,Cell Line, Tumor ,medicine ,Humans ,Molecular Biology ,Tumor microenvironment ,Cancer ,Hydrogen Peroxide ,General Medicine ,medicine.disease ,Carbon ,Drug Resistance, Multiple ,In vitro ,medicine.anatomical_structure ,chemistry ,Doxorubicin ,Cell culture ,Cancer research ,Female ,Biotechnology ,K562 cells - Abstract
Carbon nanodots based on L-arginine (L-Arg) were developed for enhanced nitric oxide (NO) gas therapy for cancer. The L-Arg-based carbon nanodots (Arg-dots) produced high levels of NO in the tumor environment rich in endogenous H2O2. In vitro cell experiments revealed that the Arg-dots could kill tumor cells (including human breast cancer cell line MCF-7, female gastric cancer cell line BGC-823, male lung cancer cell line A549, and female leukemic cell line K562) but did not affect the activity of normal cells (human normal lung epithelial cell line BEAS-2B). The Arg-dots produced twice the amount of NO for an equivalent amount of L-Arg. Theoretical calculations showed that the carbonization structure of the Arg-dots promoted significantly more electrons toward the guanidinium groups of L-Arg and boosted the adsorption of H2O2 molecules. In vitro and in vivo investigations confirmed that the Arg-dots reduced the multidrug resistance (MDR) effect of the tumor cells (MCF-7/ADR cells) and produced a combined antitumor efficacy with traditional chemotherapeutic drugs (adriamycin [ADR]). The fluorescence property (quantum yield, 6.88%) allows the Arg-dots to be used as a suitable fluorescent probe for fluorescence imaging of tumor cells. The ultra-small size of the Arg-dots (diameter: ca. 2.5 nm) enables them not only to penetrate deep tumors and provide enhanced antitumor activity but also to be removed through kidney filtration and have a renal clearance property. Statement of significance Nitric oxide (NO), which serves as a biological messenger, can be used in gas therapy for cancer. The development of a safe and efficient NO cancer therapy is, however, challenging because of the low NO release amount and poor tumor specificity of most NO donors. Many efforts have been made to overcome these drawbacks, but solving both these limitations through a single approach has been seldom achieved. In the present work, carbon nanodots (Arg-dots) from L-arginine were used for gas therapy of cancer. The Arg-dots produced NO in the H2O2-rich tumor environment. Theoretical calculations were consistent with the mechanism of enhanced NO release amount. The Arg-dots also reduced the multidrug resistance effect in cancer chemotherapy. In vivo and in vitro toxicity assessments confirmed that the Arg-dots have excellent biosafety.
- Published
- 2021
25. Diabetes complications and extracellular vesicle therapy
- Author
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Reza Yarani, Setareh Soltani, Kamran Mansouri, Flemming Pociot, shahram parvaneh, and Avnesh S. Thakor
- Subjects
business.industry ,Endocrinology, Diabetes and Metabolism ,Blood sugar ,Extracellular vesicle ,medicine.disease ,Bioinformatics ,Chronic disorders ,Microvesicles ,Endocrinology ,Diabetes mellitus ,medicine ,Stem cell ,business ,Pathological ,Glycemic - Abstract
Diabetes is a chronic disorder characterized by dysregulated glycemic conditions. Diabetic complications include microvascular and macrovascular abnormalities and account for high morbidity and mortality rates in patients. Current clinical approaches for diabetic complications are limited to symptomatic treatments and tight control of blood sugar levels. Extracellular vesicles (EVs) released by somatic and stem cells have recently emerged as a new class of potent cell-free therapeutic delivery packets with a great potential to treat diabetic complications. EVs contain a mixture of bioactive molecules and can affect underlying pathological processes in favor of tissue healing. In addition, EVs have low immunogenicity and high storage capacity while maintaining nearly the same regenerative and immunomodulatory effects compared to current cell-based therapies. Therefore, EVs have received increasing attention for diabetes-related complications in recent years. In this review, we provide an outlook on diabetic complications and summarizes new knowledge and advances in EV applications. Moreover, we highlight recommendations for future EV-related research.
- Published
- 2021
26. Update on Pediatric Interventional Radiology
- Author
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Victoria A. Young, Avnesh S. Thakor, and Shellie C. Josephs
- Subjects
Adolescent ,Humans ,Infant ,Radiology, Nuclear Medicine and imaging ,Radiology, Interventional ,Child - Abstract
The field of pediatric interventional radiology encompasses the treatment of a broad range of patients. Whether treating a premature infant who weighs less than 1 kg or treating an adult-sized teenager who weighs more than 100 kg, the innovative skills of the interventional radiologist are required to adapt equipment designed for adult patients, to meet the needs of children. Moreover, children cannot be treated simply as small adults owing to a number of factors, including differences in physiology, disease processes, and treatment techniques between pediatric and adult patients. In this article, the unique medical needs of children are highlighted, noting specific areas the interventional radiologist should be aware of when treating patients of all ages. Specific focus is placed on the unique considerations related to children in terms of their periprocedural needs and the procedural modifications required for routine pediatric procedures, with specific diseases of the liver, chest, and musculoskeletal system highlighted. The broader topic of vascular anomalies, although an important part of pediatric interventional radiology, was intentionally excluded to highlight some of the lesser-known procedures performed.
- Published
- 2022
27. Umbilical cord mesenchymal stromal cells-from bench to bedside
- Author
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Shashank Chetty, Reza Yarani, Ganesh Swaminathan, Rosita Primavera, Shobha Regmi, Sravanthi Rai, Jim Zhong, Abantika Ganguly, and Avnesh S Thakor
- Subjects
Cell Biology ,Developmental Biology - Abstract
In recent years, mesenchymal stromal cells (MSCs) have generated a lot of attention due to their paracrine and immuno-modulatory properties. mesenchymal stromal cells derived from the umbilical cord (UC) are becoming increasingly recognized as having increased therapeutic potential when compared to mesenchymal stromal cells from other sources. The purpose of this review is to provide an overview of the various compartments of umbilical cord tissue from which mesenchymal stromal cells can be isolated, the differences and similarities with respect to their regenerative and immuno-modulatory properties, as well as the single cell transcriptomic profiles of in vitro expanded and freshly isolated umbilical cord-mesenchymal stromal cells. In addition, we discuss the therapeutic potential and biodistribution of umbilical cord-mesenchymal stromal cells following systemic administration while providing an overview of pre-clinical and clinical trials involving umbilical cord-mesenchymal stromal cells and their associated secretome and extracellular vesicles (EVs). The clinical applications of umbilical cord-mesenchymal stromal cells are also discussed, especially in relation to obstacles and potential solutions for their effective translation from bench to bedside.
- Published
- 2022
28. Blood Oxygen Level-Dependent (BOLD) MRI in Glomerular Disease
- Author
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Raymond Wong, Sophia Hu, Avnesh S. Thakor, Puneet Gupta, and Daniel R. Nemirovsky
- Subjects
medicine.medical_specialty ,Adverse outcomes ,lcsh:Surgery ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,Nephritic syndrome ,0302 clinical medicine ,Internal medicine ,Diabetes mellitus ,Medicine ,Glomerular disease ,Blood-oxygen-level dependent ,medicine.diagnostic_test ,business.industry ,hypoxia ,nephritic ,glomerular ,nephrotic ,Magnetic resonance imaging ,lcsh:RD1-811 ,Hypoxia (medical) ,medicine.disease ,Cardiology ,medicine.symptom ,BOLD MRI ,business ,Nephrotic syndrome ,030217 neurology & neurosurgery - Abstract
Renal hypoxia has recently been implicated as a key contributor and indicator of various glomerular diseases. As such, monitoring changes in renal oxygenation in these disorders may provide an early diagnostic advantage that could prevent potential adverse outcomes. Blood oxygen level-dependent magnetic resonance imaging (BOLD MRI) is an emerging noninvasive technique for assessing renal oxygenation in glomerular disease. Although BOLD MRI has produced promising initial results for the use in certain renal pathologies, the use of BOLD imaging in glomerular diseases, including primary and secondary nephrotic and nephritic syndromes, is relatively unexplored. Early BOLD studies on primary nephrotic syndrome, nephrotic syndrome secondary to diabetes mellitus, and nephritic syndrome secondary to systemic lupus erythematosus have shown promising results to support its future clinical utility. In this review, we outline the advancements made in understanding the use of BOLD MRI for the assessment, diagnosis, and screening of these pathologies.
- Published
- 2021
29. Case Series of Precision Delivery of Methylprednisolone in Pediatric Inflammatory Bowel Disease: Feasibility, Clinical Outcomes, and Identification of a Vasculitic Transcriptional Program
- Author
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Steven Levitte, Reza Yarani, Abantika Ganguly, Lynne Martin, John Gubatan, Helen R. Nadel, Benjamin Franc, Roberto Gugig, Ali Syed, Alka Goyal, K. T. Park, and Avnesh S. Thakor
- Subjects
General Medicine - Abstract
Systemic steroid exposure, while useful for the treatment of acute flares in inflammatory bowel disease (IBD), is associated with an array of side effects that are particularly significant in children. Technical advancements have enabled locoregional intraarterial steroid delivery directly into specific segments of the gastrointestinal tract, thereby maximizing tissue concentration while limiting systemic exposure. We investigated the feasibility of intraarterial steroid administration into the bowel in a cohort of nine pediatric patients who had IBD. This treatment approach provided symptom relief in all patients, with sustained relief (>2 weeks) in seven out of nine; no serious adverse effects occurred in any patient. In addition, we identified patterns of vascular morphologic changes indicative of a vasculopathy within the mesenteric circulation of inflamed segments of the bowel in pediatric patients with Crohn’s disease, which correlated with disease activity. An analysis of publicly available transcriptomic studies identified vasculitis-associated molecular pathways activated in the endothelial cells of patients with active Crohn’s disease, suggesting a possible shared transcriptional program between vasculitis and IBD. Intraarterial corticosteroid treatment is safe and has the potential to be widely accepted as a locoregional approach for therapy delivery directly into the bowel; however, this approach still warrants further consideration as a short-term “bridge” between therapy transitions for symptomatic IBD patients with refractory disease, as part of a broader steroid-minimizing treatment strategy.
- Published
- 2023
30. Integrated transcriptome-proteome analyses of human stem cells reveal source-dependent differences in their regenerative signature
- Author
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Abantika Ganguly, Ganesh Swaminathan, Fernando Garcia-Marques, Shobha Regmi, Reza Yarani, Rosita Primavera, Shashank Chetty, Abel Bermudez, Sharon J. Pitteri, and Avnesh S. Thakor
- Subjects
Genetics ,Cell Biology ,Biochemistry ,Developmental Biology - Abstract
Mesenchymal stem cells (MSCs) are gaining increasing prominence as an effective regenerative cellular therapy. However, ensuring consistent and reliable effects across clinical populations has proved to be challenging. In part, this can be attributed to heterogeneity in the intrinsic molecular and regenerative signature of MSCs, which is dependent on their source of origin. The present work uses integrated omics-based profiling, at different functional levels, to compare the anti-inflammatory, immunomodulatory, and angiogenic properties between MSCs from neonatal (umbilical cord MSC [UC-MSC]) and adult (adipose tissue MSC [AD-MSC], and bone marrow MSC [BM-MSC]) sources. Using multi-parametric analyses, we identified that UC-MSCs promote a more robust host innate immune response; in contrast, adult-MSCs appear to facilitate remodeling of the extracellular matrix (ECM) with stronger activation of angiogenic cascades. These data should help facilitate the standardization of source-specific MSCs, such that their regenerative signatures can be confidently used to target specific disease processes.
- Published
- 2022
31. Dynamic Hydrodissection for Skin Protection during Cryoablation of Superficial Lesions
- Author
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Jesse K. Sandberg, Avnesh S. Thakor, Matthew P. Lungren, Shellie Josephs, Victoria A. Young, and Kevin R. Shoaf
- Subjects
Skin protection ,medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Medicine ,Radiology, Nuclear Medicine and imaging ,Cryoablation ,Radiology ,Cardiology and Cardiovascular Medicine ,business - Published
- 2020
32. Controlled Nutrient Delivery to Pancreatic Islets Using Polydopamine-Coated Mesoporous Silica Nanoparticles
- Author
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Jing Wang, Peter Buchwald, Mehdi Razavi, Mujib Ullah, Avnesh S. Thakor, Bhavesh D. Kevadiya, and Rosita Primavera
- Subjects
Indoles ,Polymers ,Nanoparticle ,Bioengineering ,02 engineering and technology ,Article ,Diabetes Mellitus, Experimental ,Islets of Langerhans ,Mice ,medicine ,Animals ,General Materials Science ,geography ,geography.geographical_feature_category ,Chemistry ,Mechanical Engineering ,Pancreatic islets ,Diabetic mouse ,Nutrients ,General Chemistry ,Mesoporous silica ,Silicon Dioxide ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Islet ,Transplantation ,Glutamine ,medicine.anatomical_structure ,Biophysics ,Nanoparticles ,0210 nano-technology ,Porosity - Abstract
In the present study, we created a nanoscale platform that can deliver nutrients to pancreatic islets in a controlled manner. Our platform consists of a mesoporous silica nanoparticle (MSNP), which can be loaded with glutamine (G: an essential amino acid required for islet survival and function). To control the release of G, MSNPs were coated with a polydopamine (PD) layer. With the optimal parameters (0.5 mg/mL and 0.5 h), MSNPs were coated with a layer of PD, which resulted in a delay of G release from MSNPs over 14 d (57.4 ± 4.7% release). Following syngeneic renal subcapsule islet transplantation in diabetic mice, PDG-MSNPs improved the engraftment of islets (i.e., enhanced revascularization and reduced inflammation) as well as their function, resulting in re-establishment of glycemic control. Collectively, our data show that PDG-MSNPs can support transplanted islets by providing them with a controlled and sustained supply of nutrients.
- Published
- 2020
33. The role of ultrasound in enhancing mesenchymal stromal cell‐based therapies
- Author
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Mujib Ullah, Jeremy J. Dahl, Avnesh S. Thakor, Waldo Concepcion, and Daniel D. Liu
- Subjects
0301 basic medicine ,Stromal cell ,Cell- and Tissue-Based Therapy ,regenerative medicine ,low‐intensity ultrasound ,Concise Reviews ,Regenerative medicine ,Cell therapy ,03 medical and health sciences ,0302 clinical medicine ,Medicine ,Humans ,lcsh:QH573-671 ,Ultrasonography ,lcsh:R5-920 ,business.industry ,Cell adhesion molecule ,Concise Review ,ultrasound ,lcsh:Cytology ,Mesenchymal stem cell ,Ultrasound ,Cell Differentiation ,Mesenchymal Stem Cells ,Cell Biology ,General Medicine ,extracorporeal shockwave therapy ,030104 developmental biology ,Microbubbles ,focused ultrasound ,cell therapy ,homing ,business ,mesenchymal stromal cells ,lcsh:Medicine (General) ,Neuroscience ,030217 neurology & neurosurgery ,Developmental Biology ,Homing (hematopoietic) - Abstract
Mesenchymal stromal cells (MSCs) have been a popular platform for cell‐based therapy in regenerative medicine due to their propensity to home to damaged tissue and act as a repository of regenerative molecules that can promote tissue repair and exert immunomodulatory effects. Accordingly, a great deal of research has gone into optimizing MSC homing and increasing their secretion of therapeutic molecules. A variety of methods have been used to these ends, but one emerging technique gaining significant interest is the use of ultrasound. Sound waves exert mechanical pressure on cells, activating mechano‐transduction pathways and altering gene expression. Ultrasound has been applied both to cultured MSCs to modulate self‐renewal and differentiation, and to tissues‐of‐interest to make them a more attractive target for MSC homing. Here, we review the various applications of ultrasound to MSC‐based therapies, including low‐intensity pulsed ultrasound, pulsed focused ultrasound, and extracorporeal shockwave therapy, as well as the use of adjunctive therapies such as microbubbles. At a molecular level, it seems that ultrasound transiently generates a local gradient of cytokines, growth factors, and adhesion molecules that facilitate MSC homing. However, the molecular mechanisms underlying these methods are far from fully elucidated and may differ depending on the ultrasound parameters. We thus put forth minimal criteria for ultrasound parameter reporting, in order to ensure reproducibility of studies in the field. A deeper understanding of these mechanisms will enhance our ability to optimize this promising therapy to assist MSC‐based approaches in regenerative medicine., Mesenchymal stromal cells (MSCs) are a promising platform for regenerative medicine, but their therapeutic efficacy still requires optimization. Ultrasound (US) can enhance MSC‐based therapies through a variety of strategies. When applied to MSCs in vitro, US modulates self‐renewal and differentiation. When applied to target organs in vivo, US enhances MSC homing by upregulating local cytokines and adhesion molecules.
- Published
- 2020
34. Reversing Acute Kidney Injury Using Pulsed Focused Ultrasound and MSC Therapy: A Role for HSP-Mediated PI3K/AKT Signaling
- Author
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Waldo Concepcion, Sravanthi Rai, Daniel D. Liu, Avnesh S. Thakor, Sriya Jonnakuti, Mujib Ullah, and Arya Dadhania
- Subjects
0301 basic medicine ,Stromal cell ,lcsh:QH426-470 ,heat shock protein ,Inflammation ,Article ,03 medical and health sciences ,0302 clinical medicine ,Downregulation and upregulation ,Genetics ,medicine ,lcsh:QH573-671 ,Molecular Biology ,Protein kinase B ,PI3K/AKT/mTOR pathway ,business.industry ,lcsh:Cytology ,Mesenchymal stem cell ,apoptosis ,Acute kidney injury ,medicine.disease ,kidney regeneration ,lcsh:Genetics ,030104 developmental biology ,acute kidney injury ,inflammation ,030220 oncology & carcinogenesis ,mesenchymal stromal cell ,Cancer research ,Molecular Medicine ,focused ultrasound ,medicine.symptom ,business ,signaling ,Homing (hematopoietic) - Abstract
Acute kidney injury (AKI) is characterized by a sudden failure of renal function, but despite increasing worldwide prevalence, current treatments are largely supportive, with no curative therapies. Mesenchymal stromal cell (MSC) therapy has been shown to have a promising regenerative effect in AKI but is limited by the ability of cells to home to damaged tissue. Pulsed focused ultrasound (pFUS), wherein target tissues are sonicated by short bursts of sound waves, has been reported to enhance MSC homing by upregulating local homing signals. However, the exact mechanism by which pFUS enhances MSC therapy remains insufficiently explored. In this study, we studied the effect of bone marrow-derived MSCs (BM-MSCs), in conjunction with pFUS, in a mouse model of cisplatin-induced AKI. Here, BM-MSCs improved kidney function, reduced histological markers of kidney injury, decreased inflammation and apoptosis, and promoted cellular proliferation. Surprisingly, whereas pFUS did not upregulate local cytokine expression or improve BM-MSC homing, it did potentiate the effect of MSC treatment in AKI. Further analysis linked this effect to the upregulation of heat shock protein (HSP)20/HSP40 and subsequent phosphatidylinositol 3-kinase (PI3K)/Akt signaling. In summary, our results suggest that pFUS and BM-MSCs have independent as well as synergistic therapeutic effects in the context of AKI., Graphical Abstract, Mesenchymal stromal cells (MSCs) have shown promise in kidney regeneration following acute kidney injury. However, their therapeutic efficacy still requires optimization, which may be accomplished using pulsed focused ultrasound (pFUS). Here, Ullah et al. show how MSCs and pFUS have both independent and synergistic roles in promoting kidney regeneration.
- Published
- 2020
35. Hybrid Polydimethylsiloxane Bioscaffold-Intravascular Catheter for Cellular Therapies
- Author
-
Avnesh S. Thakor, Jing Wang, Rosita Primavera, Mehdi Razavi, Sophia Hu, and Anirudh Avadhani
- Subjects
endocrine system ,geography ,Pathology ,medicine.medical_specialty ,geography.geographical_feature_category ,endocrine system diseases ,business.industry ,Insulin deficiency ,Pancreatic islets ,Biochemistry (medical) ,Biomedical Engineering ,nutritional and metabolic diseases ,General Chemistry ,medicine.disease ,Islet ,Biomaterials ,Transplantation ,Catheter ,medicine.anatomical_structure ,Intravascular catheter ,Diabetes mellitus ,Medicine ,business - Abstract
Type-1 diabetes (T1D) is caused by immune-mediated destruction of insulin-producing beta-cells, resulting in insulin deficiency and hyperglycemia. Islet transplantation is a potential treatment for T1D, but clinical implementation is hampered by islet availability and poor islet survival post-transplantation. To overcome these issues, we developed an intravascular multiside hole catheter with an interior polydimethylsiloxane (PDMS) bioscaffold capable of housing a cellular cargo. We used computational fluid dynamics to determine an optimized catheter design, which we then fabricated. Using our hybrid PDMS bioscaffold-intravascular catheter, we demonstrated that this platform can successfully maintain
- Published
- 2022
36. Adipose stem cell homing and routes of delivery
- Author
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Avnesh S. Thakor, Bhavesh D. Kevadiya, Yang Qiao, Lucille A. Bresette, Daniel D. Liu, and Ganesh Swaminathan
- Subjects
endocrine system ,business.industry ,animal diseases ,Stem cell homing ,Mesenchymal stem cell ,Cell ,Adipose tissue ,hemic and immune systems ,Tissue repair ,eye diseases ,Cell biology ,medicine.anatomical_structure ,medicine ,Stem cell ,business ,tissues ,Homing (hematopoietic) - Abstract
Adipose stem cells (ASCs) are multipotent mesenchymal stem cells that are involved in regenerative tissue repair. Upon injury, a gradient of signals promotes migration and homing of ASCs at the site of injury. Toward applying ASCs for regenerative therapies, several homing strategies are investigated including magnetically guiding ASCs to target tissues upon labeling with magnetic nanoparticles. Alternatively, targeted delivery of ASCs at the site of injury is also assessed. While the intravenous delivery has been tested in both preclinical and clinical studies, efficacy of localized delivery via intraarterial, intraparenchymal, and intramyocardial injections is currently tested for cell-based regenerative therapies.
- Published
- 2022
37. Contributors
- Author
-
Rosalyn D. Abbott, Sandeep Adem, Sara I. Al-Ghadban, François A. Auger, Jocelyn S. Baker, Fuat Baris Bengur, Lucille A. Bresette, Aaron C. Brown, Bruce A. Bunnell, Louis Casteilla, Gregorio D. Chazenbalk, Mary Ann Chirba, Adam Cottrill, Béatrice Cousin, Christian Dani, Vincent Dani, Francesco M. Egro, Asim Ejaz, Roberto D. Fanganiello, Nathalie Faucheux, Lauren Flynn, Julie Fradette, Mallory D. Griffin, Mark A.A. Harrison, Jessica Jann, Veronica Morgan Jones, Adam J. Katz, Fabien Kawecki, Bhavesh D. Kevadiya, Lauren Kokai, Karen L. Leung, Daniel D. Liu, Shawn Loder, Michael T. Longaker, Kacey Marra, Danielle Minteer, Omair A. Mohiuddin, Benjamen T. O’Donnell, Hakan Orbay, George E. Panagis, Ivona Percec, Yang Qiao, Ricardo Rodriguez, J. Peter Rubin, David E. Sahar, Ankit Salhotra, Yasamin Samadi, Benjamin K. Schilling, Harsh N. Shah, Xiaoyin Shan, Abra H. Shen, Patsy Simon, Brianne N. Sullivan, Ganesh Swaminathan, Avnesh S. Thakor, Matthias Waldner, John Walker, Derrick C. Wan, Rachel M. Wise, and Xi Yao
- Published
- 2022
38. Human placenta-derived mesenchymal stromal cells transfusion in a critically Ill infant diagnosed with Coronavirus Disease 2019 (COVID-19): A case report
- Author
-
Mehrdad Payandeh, Reza Habibi, Amir Hossein Norooznezhad, Zohreh Hoseinkhani, Feizollah Mansouri, Reza Yarani, Avnesh S. Thakor, Mitra Bakhtiari, Farzaneh Esmailli, and Kamran Mansouri
- Subjects
Male ,Pregnancy ,SARS-CoV-2 ,Critical Illness ,Placenta ,Humans ,COVID-19 ,Female ,Mesenchymal Stem Cells ,Hematology ,Child - Abstract
Coronavirus disease 2019 (COVID-19) is still an emergency in many countries. Herein, we report treatment with human placental-derived mesenchymal stromal cells transfusion (hPD-MSCT) in a critically ill infant diagnosed with COVID-19. A 28-day-old male infant with a history of pneumonia was referred to our center with decreased SpO
- Published
- 2021
39. Autologous conditioned serum for degenerative diseases and prospects
- Author
-
Seyed Kazem Shakouri, Sanam Dolati, Jessica Santhakumar, Avnesh S. Thakor, and Reza Yarani
- Subjects
Serum ,Interleukin 1 Receptor Antagonist Protein ,Endocrinology ,Clinical Biochemistry ,Cytokines ,Intercellular Signaling Peptides and Proteins ,Cell Biology - Abstract
Autologous conditioned serum (ACS) is a blood-derived product that is prepared by the incubation of whole blood with medical-grade glass beads, resulting in serum enrichment in interleukin-1 receptor antagonist (IL-1Ra), anti-inflammatory cytokines (IL-4, IL-10, and IL-13), and high concentrations of growth factors. ACS has shown qualitatively and quantitatively better therapeutic effects than most established pharmacological treatments and surgery for joint diseases given its ability to both target the inflammatory cascade to decrease cartilage destruction as well as improve endogenous repair mechanisms. ACS application is simple and safe with limited adverse effects. This article reviews the role of ACS in degenerative joint disease, in addition to other inflammatory and autoimmune diseases, given its regenerative and immune-modulating properties.
- Published
- 2021
40. Localized drug delivery graphene bioscaffolds for cotransplantation of islets and mesenchymal stem cells
- Author
-
Avnesh S. Thakor, Jing Wang, and Mehdi Razavi
- Subjects
endocrine system ,geography ,Multidisciplinary ,geography.geographical_feature_category ,Graphene ,Chemistry ,fungi ,Mesenchymal stem cell ,food and beverages ,Adipose tissue ,SciAdv r-articles ,Islet ,law.invention ,Cell biology ,Engineering ,law ,Jing wang ,Drug delivery ,polycyclic compounds ,medicine ,Biomedicine and Life Sciences ,hormones, hormone substitutes, and hormone antagonists ,Dexamethasone ,medicine.drug ,Research Article - Abstract
Description, A stem cell seeded graphene-dexamethasone bioscaffold significantly improves the survival and function of transplanted islets., In the present work, we developed, characterized, and tested an implantable graphene bioscaffold which elutes dexamethasone (Dex) that can accommodate islets and adipose tissue–derived mesenchymal stem cells (AD-MSCs). In vitro studies demonstrated that islets in graphene–0.5 w/v% Dex bioscaffolds had a substantial higher viability and function compared to islets in graphene-alone bioscaffolds or islets cultured alone (P < 0.05). In vivo studies, in which bioscaffolds were transplanted into the epididymal fat pad of diabetic mice, demonstrated that, when islet:AD-MSC units were seeded into graphene–0.5 w/v% Dex bioscaffolds, this resulted in complete restoration of glycemic control immediately after transplantation with these islets also showing a faster response to glucose challenges (P < 0.05). Hence, this combination approach of using a graphene bioscaffold that can be functionalized for local delivery of Dex into the surrounding microenvironment, together with AD-MSC therapy, can significantly improve the survival and function of transplanted islets.
- Published
- 2021
41. Diabetes complications and extracellular vesicle therapy
- Author
-
Setareh, Soltani, Kamran, Mansouri, Shahram, Parvaneh, Avnesh S, Thakor, Flemming, Pociot, and Reza, Yarani
- Subjects
Blood Glucose ,Diabetes Complications ,Extracellular Vesicles ,Wound Healing ,Diabetes Mellitus ,Humans - Abstract
Diabetes is a chronic disorder characterized by dysregulated glycemic conditions. Diabetic complications include microvascular and macrovascular abnormalities and account for high morbidity and mortality rates in patients. Current clinical approaches for diabetic complications are limited to symptomatic treatments and tight control of blood sugar levels. Extracellular vesicles (EVs) released by somatic and stem cells have recently emerged as a new class of potent cell-free therapeutic delivery packets with a great potential to treat diabetic complications. EVs contain a mixture of bioactive molecules and can affect underlying pathological processes in favor of tissue healing. In addition, EVs have low immunogenicity and high storage capacity while maintaining nearly the same regenerative and immunomodulatory effects compared to current cell-based therapies. Therefore, EVs have received increasing attention for diabetes-related complications in recent years. In this review, we provide an outlook on diabetic complications and summarizes new knowledge and advances in EV applications. Moreover, we highlight recommendations for future EV-related research.
- Published
- 2021
42. A Study Comparing the Effects of Targeted Intra-Arterial and Systemic Chemotherapy in an Orthotopic Mouse Model of Pancreatic Cancer
- Author
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Mujib Ullah, Fengyan Zheng, Jing Wang, Ahmed Hussein, Gang Ren, Melika Rezaee, Mehdi Razavi, and Avnesh S. Thakor
- Subjects
Male ,0301 basic medicine ,Antimetabolites, Antineoplastic ,medicine.medical_specialty ,Neoplasm, Residual ,Transplantation, Heterologous ,Urology ,Mice, Nude ,lcsh:Medicine ,Deoxycytidine ,Article ,Drug Administration Schedule ,Mice ,03 medical and health sciences ,Targeted therapies ,0302 clinical medicine ,Cell Line, Tumor ,Pancreatic cancer ,medicine ,Animals ,Humans ,Infusions, Intra-Arterial ,Neoplasm ,Cancer models ,lcsh:Science ,Multidisciplinary ,Dose-Response Relationship, Drug ,business.industry ,Therapeutic effect ,lcsh:R ,medicine.disease ,Gemcitabine ,Pancreatic Neoplasms ,Transplantation ,Disease Models, Animal ,Dose–response relationship ,030104 developmental biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Toxicity ,Administration, Intravenous ,Female ,lcsh:Q ,Pancreas ,business ,medicine.drug - Abstract
Systemic chemotherapy is the first line treatment for patients with unresectable pancreatic cancer, however, insufficient drug delivery to the pancreas is a major problem resulting in poor outcomes. We evaluated the therapeutic effects of targeted intra-arterial (IA) delivery of gemcitabine directly into the pancreas in an orthotopic mouse model of pancreatic cancer. Nude mice with orthotopic pancreatic tumors were randomly assigned into 3 groups receiving gemcitabine: systemic intravenous (IV) injection (low: 0.3 mg/kg and high: 100 mg/kg) and direct IA injection (0.3 mg/kg). Treatments were administered weekly for 2 weeks. IA treatment resulted in a significantly greater reduction in tumor growth compared to low IV treatment. To achieve a comparable reduction in tumor growth as seen with IA treatment, gemcitabine had to be given IV at over 300x the dose (high IV treatment) which was associated with some toxicity. After 2 weeks, tumor samples from animals treated with IA gemcitabine had significantly lower residual cancer cells, higher cellular necrosis and evidence of increased apoptosis when compared to animals treated with low IV gemcitabine. Our study shows targeted IA injection of gemcitabine directly into the pancreas, via its arterial blood supply, has a superior therapeutic effect in reducing tumor growth compared to the same concentration administered by conventional systemic injection.
- Published
- 2019
43. Imaging Tumor Oxidative Stress with Surface Enhanced Raman Scattering Gold Nanoparticles
- Author
-
Jing Wang, Avnesh S. Thakor, Mehdi Razavi, Gang Ren, and Richard Kimura
- Subjects
Silicon dioxide ,Biomedical Engineering ,Metal Nanoparticles ,Pharmaceutical Science ,Medicine (miscellaneous) ,Nanoparticle ,Bioengineering ,Spectrum Analysis, Raman ,medicine.disease_cause ,symbols.namesake ,chemistry.chemical_compound ,Neoplasms ,medicine ,Animals ,Humans ,General Materials Science ,chemistry.chemical_classification ,Reactive oxygen species ,Chemistry ,Cystine knot ,Silicon Dioxide ,Oxidative Stress ,Colloidal gold ,symbols ,Biophysics ,Gold ,Raman spectroscopy ,Raman scattering ,Oxidative stress - Abstract
We synthesized a new surface enhanced Raman scattering nanoparticle (SERS NP) which can detect reactive oxygen species (ROS) and thus changes in oxidative stress (OS). Our SERS NP was synthesized using a gold nanoparticle (AuNP) core which was then coated with a dihydrorhodamine (DHR123) Raman layer. In the presence of ROS, DHR123 is converted to rhodamine123 (Rd123) which has a distinct Raman fingerprint. Next, AuNP-DHR123 were encapsulated in a mesoporous-SiO2 shell to help appose DHR123 to the AuNP core. Finally, the AuNP-DHR123-mesoporous-SiO2 was functionalized with cystine knot peptides that target integrin αvβ6. Our SERS NP was initially optimized in vitro using solutions containing reactive oxygen species as well as human cancer cell lines. Finally, in a xenograft animal model, we demonstrated the in vivo ability of our SERS NP to target a tumor, as well as provide a reading of the amount of OS within the tumor.
- Published
- 2019
44. Ferumoxytol Does Not Impact Standardized Uptake Values on PET/MR Scans
- Author
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Raffi S. Avedian, Ashok J. Theruvath, Jarrett Rosenberg, Anne M. Muehe, Heike E. Daldrup-Link, Ketan Yerneni, Allison Pribnow, Robert J. Steffner, Kristina Elizabeth Hawk, and Avnesh S. Thakor
- Subjects
Male ,Cancer Research ,Adolescent ,Gadolinium ,Contrast Media ,chemistry.chemical_element ,For Attenuation Correction ,Multimodal Imaging ,Article ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Fluorodeoxyglucose F18 ,Neoplasms ,medicine ,Humans ,Image acquisition ,Drug Interactions ,Whole Body Imaging ,Radiology, Nuclear Medicine and imaging ,Child ,Clinical Trials as Topic ,medicine.diagnostic_test ,business.industry ,Soft tissue ,Magnetic resonance imaging ,Magnetic Resonance Imaging ,Ferrosoferric Oxide ,Ferumoxytol ,Treatment Outcome ,Oncology ,chemistry ,Positron emission tomography ,Positron-Emission Tomography ,Female ,Radiopharmaceuticals ,business ,Nuclear medicine ,Correction for attenuation - Abstract
PURPOSE: Tumor response assessments on positron emission tomography (PET)/magnetic resonance imaging (MRI) scans requires correct quantification of radiotracer uptake in tumors and normal organs. Historically, MRI scans have been enhanced with gadolinium (Gd) based contrast agents, which are now controversial due to brain deposition. Recently, ferumoxytol nanoparticles have been identified as an alternative to Gd-based contrast agents, because they provide strong tissue enhancement on MR images but are not deposited in the brain. However, it is not known if the strong T1- and T2-contrast obtained with iron oxide nanoparticles such as ferumoxytol could affect MR-based attenuation correction of PET data. The purpose of our study was to investigate, if a ferumoxytol administration prior to a 2-deoxy-2-[(18)F]fluoro-D-glucose [(18)F]FDG PET/MR scan would change standardized uptake values (SUV) of normal organs. PROCEDURES: 30 pediatric patients (6-18 years) with malignant tumors underwent [(18)F]FDG-PET/MR scans (dose 3 MBq/kg). Fifteen patients received an intravenous ferumoxytol injection (5 mg Fe/kg) prior to the [(18)F]FDG-PET/MR scans (group 1). 15 additional age- and sex-matched patients received unenhanced [(18)F]FDG-PET/MR scans (group 2). For attenuation correction of PET data, we used a Dixon-based gradient echo sequence (TR 4.2 ms, TE 1. 1, 2.3 ms, FA 5), which accounted for soft tissue, lung, fat and background air. We used a mixed linear effects model to compare the tissue MRI enhancement, quantified as the signal-to-noise ratio (SNR), as well as tissue radiotracer signal, quantified as SUVmean and SUVmax, between group1 and group 2. Alpha was assumed at 0.05. RESULTS: The MRI enhancement of the blood and solid extra-cerebral organs, quantified as SNR, was significantly higher on ferumoxytol-enhanced MRI scans compared to unenhanced scans (p < 0.001). However, SUVmean and SUVmax values, corrected based on the patients body weight or body surface area, were not significantly different between the two groups (p > 0.05). CONCLUSION: Ferumoxytol administration prior to a [(18)F]FDG PET/MR scan did not change standardized uptake values (SUV) of solid extra-cerebral organs. This is important, because it allows to inject ferumoxytol contrast prior to a PET/MRI procedure and thereby, significantly accelterate image acquisition times.
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- 2019
45. Mesenchymal stem cells confer chemoresistance in breast cancer via a CD9 dependent mechanism
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Nathan Ng, Asma Akbar, Waldo Concepcion, Avnesh S. Thakor, and Mujib Ullah
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0301 basic medicine ,medicine.medical_treatment ,Cell ,MSCs ,CCL5 ,03 medical and health sciences ,0302 clinical medicine ,Breast cancer ,cytokine ,Medicine ,Doxorubicin ,Tumor microenvironment ,business.industry ,xenograft tumors ,Mesenchymal stem cell ,chemoresistance ,CD9 ,medicine.disease ,030104 developmental biology ,medicine.anatomical_structure ,Cytokine ,Oncology ,Tumor progression ,030220 oncology & carcinogenesis ,Cancer research ,business ,Research Paper ,medicine.drug - Abstract
The development of chemotherapy drug resistance remains a significant barrier for effective therapy in several cancers including breast cancer. Bone marrow-derived mesenchymal stem cells (BMMSCs) have previously been shown to influence tumor progression and the development of chemoresistance. In the present study, we showed that when GFP labelled BMMSCs and RFP labelled HCC1806 cells are injected together in vivo, they create tumors which contain a new hybrid cell that has characteristics of both BMMSCs and HCC1806 cells. By labelling these cells prior to their injection, we were then able to isolate new hybrid cell from harvested tumors using FACS (DP-HCC1806:BMMSCs). Interestingly, when DP-HCC1806:BMMSCs were then injected into the mammary fat pad of NOD/SCID mice, they produced xenograft tumors which were smaller in size, and exhibited resistance to chemotherapy drugs (i.e. doxorubicin and 5-fluorouracil), when compared tumors from HCC1806 cells alone. This chemoresistance was shown to associated with an increased expression of tetraspanins (CD9, CD81) and drug resistance proteins (BCRP, MDR1). Subsequent siRNA-mediated knockdown of BMMSC-CD9 in DP-HCC1806:BMMSCs resulted in an attenuation of doxorubicin and 5-fluorouracil chemoresistance associated with decreased BCRP and serum cytokine expression (CCL5, CCR5, CXCR12). Our findings suggest that within the tumor microenvironment, CD9 is responsible for the crosstalk between BMMSCs and HCC1806 breast cancer cells (via CCL5, CCR5, and CXCR12) which contributes to chemoresistance. Hence, BMMSC-CD9 may serve as an important therapeutic target for the treatment of breast cancer.
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- 2019
46. Artificial Intelligence enables whole body Positron Emission Tomography Scans with minimal radiation exposure
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Sergios Gatidis, Avnesh S. Thakor, Yan-Ran Joyce Wang, Santosh Gummidipundi, Lucia Baratto, Rong Lu, Jordi Garcia-Diaz, K. Elizabeth Hawk, Ashok J. Theruvath, Heike E. Daldrup-Link, Allison Pribnow, and Daniel L. Rubin
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Wilcoxon signed-rank test ,Image quality ,Article ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Cohen's kappa ,Artificial Intelligence ,Fluorodeoxyglucose F18 ,medicine ,Image noise ,Humans ,Radiology, Nuclear Medicine and imaging ,Whole Body Imaging ,Child ,medicine.diagnostic_test ,business.industry ,General Medicine ,Radiation Exposure ,Pediatric cancer ,Magnetic Resonance Imaging ,Radiation exposure ,Positron emission tomography ,030220 oncology & carcinogenesis ,Positron-Emission Tomography ,Artificial intelligence ,Whole body ,business - Abstract
PURPOSE: To generate diagnostic (18)F-FDG PET images of pediatric cancer patients from ultra-low dose (18)F-FDG PET input images, using a novel artificial intelligence (AI) algorithm. METHODS: We used whole body (18)F-FDG-PET/MRI scans of 33 children and young adults with lymphoma (3–30 years) to developed a convolutional neural network (CNN), which combines inputs from simulated 6.25% ultra-low-dose (18)F-FDG PET scans and simultaneously acquired MRI scans to produce a standard dose (18)F-FDG PET scan. The image quality of ultra-low-dose PET scans, AI-augmented PET scans and clinical standard PET scans was evaluated by traditional metrics in computer vision, and by expert radiologists and nuclear medicine physicians, using Wilcoxon signed rank tests and weighted kappa statistics. RESULTS: The peak signal-to-noise ratio and structural similarity index were significantly higher, and the normalized root-mean-square error significantly lower on the AI-reconstructed PET images compared to simulated 6.25% dose images (p
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- 2021
47. Loop-Mediated Isothermal Amplification (LAMP): A Rapid, Sensitive, Specific, and Cost-Eective Point-of-Care Test for Coronaviruses in the Context of COVID-19 Pandemic
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Robin Augustine, Anwarul Hasan, Suvarthi Das, Rashid Ahmed, Yasuyoshi Mori, Tsugunori Notomi, Bhavesh D. Kevadiya, and Avnesh S. Thakor
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point-of-care tests ,SARS-CoV-2 ,LAMP ,reverse transcription loop-mediated isothermal amplification ,coronavirus ,COVID-19 ,RT-LAMP - Abstract
The rampant spread of COVID-19 and the worldwide prevalence of infected cases demand a rapid, simple, and cost-eective Point of Care Test (PoCT) for the accurate diagnosis of this pandemic. The most common molecular tests approved by regulatory bodies across the world for COVID-19 diagnosis are based on Polymerase Chain Reaction (PCR). While PCR-based tests are highly sensitive, specific, and remarkably reliable, they have many limitations ranging from the requirement of sophisticated laboratories, need of skilled personnel, use of complex protocol, long wait times for results, and an overall high cost per test. These limitations have inspired researchers to search for alternative diagnostic methods that are fast, economical, and executable in low-resource laboratory settings. The discovery of Loop-mediated isothermal Amplification (LAMP) has provided a reliable substitute platform for the accurate detection of low copy number nucleic acids in the diagnosis of several viral diseases, including epidemics like Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS). At present, a cocktail of LAMP assay reagents along with reverse transcriptase enzyme (Reverse Transcription LAMP, RT-LAMP) can be a robust solution for the rapid and cost-eective diagnosis for COVID-19, particularly in developing, and low-income countries. In summary, the development of RT-LAMP based diagnostic tools in a paper/strip format or the integration of this method into a microfluidic platform such as a Lab-on-a-chip may revolutionize the concept of PoCT for COVID-19 diagnosis. This review discusses the principle, technology and past research underpinning the success for using this method for diagnosing MERS and SARS, in addition to ongoing research, and the prominent prospect of RT-LAMP in the context of COVID-19 diagnosis.
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- 2021
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48. Retraction of 'Controlled Nutrient Delivery to Pancreatic Islets Using Polydopamine-Coated Mesoporous Silica Nanoparticles'
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Mehdi Razavi, Rosita Primavera, Bhavesh D Kevadiya, Jing Wang, Mujib Ullah, Peter Buchwald, and Avnesh S Thakor
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Mechanical Engineering ,General Materials Science ,Bioengineering ,General Chemistry ,Condensed Matter Physics - Published
- 2022
49. The Paracrine Function of Mesenchymal Stem Cells in Response to Pulsed Focused Ultrasound
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Arsenii V. Telichko, Melika Rezaee, Utkan Demirci, Jeremy J. Dahl, Avnesh S. Thakor, Hakan Inan, and Mehdi Razavi
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Biomedical Engineering ,Adipose tissue ,lcsh:Medicine ,Bone Marrow Cells ,Enzyme-Linked Immunosorbent Assay ,Brief Communication ,Mesenchymal Stem Cell Transplantation ,Umbilical cord ,law.invention ,Paracrine signalling ,pulsed focused ultrasound ,Hemocytometer ,Confocal microscopy ,law ,medicine ,Humans ,Transplantation ,mesenchymal stem cells ,Microscopy, Confocal ,Mesenchymal stem cell ,lcsh:R ,paracrine function ,Cell Biology ,medicine.anatomical_structure ,Cancer research ,Bone marrow ,Function (biology) - Abstract
We studied the paracrine function of mesenchymal stem cells (MSCs) derived from various sources in response to pulsed focused ultrasound (pFUS). Human adipose tissue (AD), bone marrow (BM), and umbilical cord (UC) derived MSCs were exposed to pFUS at two intensities: 0.45 W/cm2 ISATA (310 kPa PNP) and 1.3 W/cm2 ISATA (540 kPa PNP). Following pFUS, the viability and proliferation of MSCs were assessed using a hemocytometer and confocal microscopy, and their secreted cytokine profile determined using a multiplex ELISA. Our findings showed that pFUS can stimulate the production of immunomodulatory, anti-inflammatory, and angiogenic cytokines from MSCs which was dependent on both the source of MSC being studied and the acoustic intensity employed. These important findings set the foundation for additional mechanistic and validation studies using this novel noninvasive and clinically translatable technology for modulating MSC biology.
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- 2020
50. Enhancing islet transplantation using a biocompatible collagen-PDMS bioscaffold enriched with dexamethasone-microplates
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Rosita Primavera, Jing Wang, Akshara Vykunta, Paolo Decuzzi, Avnesh S. Thakor, Mehdi Razavi, Daniele Di Mascolo, and Bhavesh D. Kevadiya
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endocrine system ,Biocompatibility ,bioscaffold ,medicine.medical_treatment ,0206 medical engineering ,Biomedical Engineering ,Islets of Langerhans Transplantation ,Bioengineering ,Inflammation ,02 engineering and technology ,Biochemistry ,Dexamethasone ,Article ,Diabetes Mellitus, Experimental ,Biomaterials ,Andrology ,Islets of Langerhans ,Mice ,Therapeutic index ,Diabetes mellitus ,medicine ,Animals ,Humans ,Insulin ,Dimethylpolysiloxanes ,geography ,geography.geographical_feature_category ,islet transplantation, bioscaffold, dexamethasone, diabetes, microplates, inflammation ,diabetes ,Chemistry ,islet transplantation ,General Medicine ,021001 nanoscience & nanotechnology ,medicine.disease ,Islet ,020601 biomedical engineering ,Transplantation ,inflammation ,Collagen ,medicine.symptom ,0210 nano-technology ,microplates ,Biotechnology ,medicine.drug - Abstract
Islet transplantation is a promising approach to enable type 1 diabetic patients to attain glycemic control independent of insulin injections. However, up to 60% of islets are lost immediately following transplantation. To improve this outcome, islets can be transplanted within bioscaffolds, however, synthetic bioscaffolds induce an intense inflammatory reaction which can have detrimental effects on islet function and survival. In the present study, we first improved the biocompatibility of polydimethylsiloxane (PDMS) bioscaffolds by coating them with collagen. To reduce the inflammatory response to PDMS bioscaffolds, we then enriched the bioscaffolds with dexamethasone-loaded microplates (DEX-μScaffolds). These DEX-microplates have the ability to release DEX in a sustained manner over 7 weeks within a therapeutic range that does not affect the glucose responsiveness of the islets but which minimizes inflammation in the surrounding microenvironment. The bioscaffold showed excellent mechanical properties that enabled it to resist pore collapse thereby helping to facilitate islet seeding and its handling for implantation, and subsequent engraftment, within the epididymal fat pad (EFP). Following the transplantation of islets into the EFP of diabetic mice using DEX-μScaffolds there was a return in basal blood glucose to normal values by day 4, with normoglycemia maintained for 30 d. Furthermore, these animals demonstrated a normal dynamic response to glucose challenges with histological evidence showing reduced pro-inflammatory cytokines and fibrotic tissue surrounding DEX-μScaffolds at the transplantation site. In contrast, diabetic animals transplanted with either islets alone or islets in bioscaffolds without DEX microplates were not able to regain glycemic control during basal conditions with overall poor islet function. Taken together, our data show that coating PDMS bioscaffolds with collagen, and enriching them with DEX-microplates, significantly prolongs and enhances islet function and survival.
- Published
- 2020
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