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Luo Z, Zhuang K, Kim SJ, Vollett KDW, Lou Z, Wang J, Cheng HYM, Khazaei M, Fehlings MG, Cheng HLM. Longitudinal Magnetic Resonance Imaging Tracking of Transplanted Neural Progenitor Cells in the Spinal Cord Utilizing the Bright-Ferritin Mechanism. Stem Cells Transl Med 2024:szae016. [PMID: 38457239 DOI: 10.1093/stcltm/szae016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2023] [Accepted: 02/04/2024] [Indexed: 03/10/2024] Open
Abstract
Human neural progenitor cells (hNPCs) hold promise for treating spinal cord injury. Studies to date have focused on improving their regenerative potential and therapeutic effect. Equally important is ensuring successful delivery and engraftment of hNPCs at the injury site. Unfortunately, no current imaging solution for cell tracking is compatible with long-term monitoring in vivo. The objective of this study was to apply a novel bright-ferritin magnetic resonance imaging (MRI) mechanism to track hNPC transplants longitudinally and on demand in the rat spinal cord. We genetically modified hNPCs to stably overexpress human ferritin. Ferritin-overexpressing (FT) hNPCs labeled with 0.2 mM manganese provided significant T1-induced bright contrast on in vitro MRI, with no adverse effect on cell viability, morphology, proliferation, and differentiation. In vivo, 2 M cells were injected into the cervical spinal cord of Rowett nude rats. MRI employed T1-weighted acquisitions and T1 mapping on a 3 T scanner. Conventional short-term cell tracking was performed using exogenous Mn labeling prior to cell transplantation, which displayed transient bright contrast on MRI 1 day after cell transplantation and disappeared after 1 week. In contrast, long-term cell tracking using bright-ferritin allowed on-demand signal recall upon Mn supplementation and precise visualization of the surviving hNPC graft. In fact, this new cell tracking technology identified 7 weeks post-transplantation as the timepoint by which substantial hNPC integration occurred. Spatial distribution of hNPCs on MRI matched that on histology. In summary, bright-ferritin provides the first demonstration of long-term, on-demand, high-resolution, and specific tracking of hNPCs in the rat spinal cord.
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Affiliation(s)
- Zixiang Luo
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Department of Spine Surgery and Orthopaedics, Xiangya Hospital, Central South University, Changsha, China
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
| | - Keyu Zhuang
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON, Canada
| | - Seong Jun Kim
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
| | - Kyle D W Vollett
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON, Canada
| | - Zijian Lou
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
| | - Jian Wang
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
| | - Hai-Ying Mary Cheng
- Department of Biology, University of Toronto Mississauga, Mississauga, ON, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada
| | - Mohamad Khazaei
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
| | - Michael G Fehlings
- Division of Genetics and Development, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Institute of Medical Sciences, University of Toronto, Toronto, ON, Canada
- Department of Surgery and Spine Program, University of Toronto, Toronto, ON, Canada
| | - Hai-Ling Margaret Cheng
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON, Canada
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, ON, Canada
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Troy AM, Normukhamedova D, Grothe D, Momen A, Zhou YQ, McFadden M, Hussain M, Billia F, Cheng HLM. Impact of ovary-intact menopause in a mouse model of heart failure with preserved ejection fraction. Am J Physiol Heart Circ Physiol 2024; 326:H522-H537. [PMID: 38180450 DOI: 10.1152/ajpheart.00733.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 12/14/2023] [Accepted: 12/29/2023] [Indexed: 01/06/2024]
Abstract
Heart failure with preserved ejection fraction (HFpEF) afflicts over half of all patients with heart failure and is a debilitating and fatal syndrome affecting postmenopausal women more than any other demographic. This bias toward older females calls into question the significance of menopause in the development of HFpEF, but this question has not been probed in detail. In this study, we report the first investigation into the impact of ovary-intact menopause in the context of HFpEF. To replicate the human condition as faithfully as possible, vinylcyclohexene dioxide (VCD) was used to accelerate ovarian failure (AOF) in female mice while leaving the ovaries intact. HFpEF was established with a mouse model that involves two stressors typical in humans: a high-fat diet and hypertension induced from the nitric oxide synthase inhibitor NG-nitro-l-arginine methyl ester (l-NAME). In young female mice, AOF or HFpEF-associated stressors independently induced abnormal myocardial strain indicative of early subclinical systolic and diastolic cardiac dysfunction. HFpEF but not AOF was associated with elevations in systolic blood pressure. Increased myocyte size and reduced myocardial microvascular density were not observed in any group. Also, a broad panel of measurements that included echocardiography, invasive pressure measurements, histology, and serum hormones revealed no interaction between AOF and HFpEF. Interestingly, AOF did evoke a higher density of infiltrating cardiac immune cells in both healthy and HFpEF mice, suggestive of proinflammatory effects. In contrast to young mice, middle-aged "old" mice did not exhibit cardiac dysfunction from estrogen deprivation alone or from HFpEF-related stressors.NEW & NOTEWORTHY This is the first preclinical study to examine the impact of ovary-intact menopause [accelerated ovarian failure (AOF)] on HFpEF. Echocardiography of young female mice revealed early evidence of diastolic and systolic cardiac dysfunction apparent only on strain imaging in HFpEF only, AOF only, or the combination. Surprisingly, AOF did not exacerbate the HFpEF phenotype. Results in middle-aged "old" females also showed no interaction between HFpEF and AOF and, importantly, no cardiovascular impact from HFpEF or AOF.
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Affiliation(s)
- Aaron M Troy
- Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
- Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, Toronto, Ontario, Canada
| | - Diyora Normukhamedova
- Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, Toronto, Ontario, Canada
| | - Daniela Grothe
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Abdul Momen
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada
| | - Yu-Qing Zhou
- Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
- Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, Toronto, Ontario, Canada
| | - Meghan McFadden
- Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
- Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, Toronto, Ontario, Canada
| | - Mansoor Hussain
- Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, Toronto, Ontario, Canada
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada
- Peter Munk Cardiac Centre, University Health Network, Toronto, Ontario, Canada
- Heart and Stroke/Richard Lewar Centre of Excellence in Cardiovascular Research, University of Toronto, Toronto, Ontario, Canada
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Filio Billia
- Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, Toronto, Ontario, Canada
- Toronto General Hospital Research Institute, University Health Network, Toronto, Ontario, Canada
- Peter Munk Cardiac Centre, University Health Network, Toronto, Ontario, Canada
- Heart and Stroke/Richard Lewar Centre of Excellence in Cardiovascular Research, University of Toronto, Toronto, Ontario, Canada
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Hai-Ling Margaret Cheng
- Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
- Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, Toronto, Ontario, Canada
- Heart and Stroke/Richard Lewar Centre of Excellence in Cardiovascular Research, University of Toronto, Toronto, Ontario, Canada
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, Ontario, Canada
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Zhuang K, Romagnuolo R, Sadikov Valdman T, Vollett KDW, Szulc DA, Cheng HYM, Laflamme MA, Cheng HLM. Bright ferritin for long-term MR imaging of human embryonic stem cells. Stem Cell Res Ther 2023; 14:330. [PMID: 37964388 PMCID: PMC10647036 DOI: 10.1186/s13287-023-03565-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 11/07/2023] [Indexed: 11/16/2023] Open
Abstract
BACKGROUND A non-invasive imaging technology that can monitor cell viability, retention, distribution, and interaction with host tissue after transplantation is needed for optimizing and translating stem cell-based therapies. Current cell imaging approaches are limited in sensitivity or specificity, or both, for in vivo cell tracking. The objective of this study was to apply a novel ferritin-based magnetic resonance imaging (MRI) platform to longitudinal tracking of human embryonic stem cells (hESCs) in vivo. METHODS Human embryonic stem cells (hESCs) were genetically modified to stably overexpress ferritin using the CRISPR-Cas9 system. Cellular toxicity associated with ferritin overexpression and manganese (Mn) supplementation were assessed based on cell viability, proliferation, and metabolic activity. Ferritin-overexpressing hESCs were characterized based on stem cell pluripotency and cardiac-lineage differentiation capability. Cells were supplemented with Mn and imaged in vitro as cell pellets on a preclinical 3 T MR scanner. T1-weighted images and T1 relaxation times were analyzed to assess contrast. For in vivo study, three million cells were injected into the leg muscle of non-obese diabetic severe combined immunodeficiency (NOD SCID) mice. Mn was administrated subcutaneously. T1-weighted sequences and T1 mapping were used to image the animals for longitudinal in vivo cell tracking. Cell survival, proliferation, and teratoma formation were non-invasively monitored by MRI. Histological analysis was used to validate MRI results. RESULTS Ferritin-overexpressing hESCs labeled with 0.1 mM MnCl2 provided significant T1-induced bright contrast on in vitro MRI, with no adverse effect on cell viability, proliferation, pluripotency, and differentiation into cardiomyocytes. Transplanted hESCs displayed significant bright contrast on MRI 24 h after Mn administration, with contrast persisting for 5 days. Bright contrast was recalled at 4-6 weeks with early teratoma outgrowth. CONCLUSIONS The bright-ferritin platform provides the first demonstration of longitudinal cell tracking with signal recall, opening a window on the massive cell death that hESCs undergo in the weeks following transplantation before the surviving cell fraction proliferates to form teratomas.
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Affiliation(s)
- Keyu Zhuang
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, 661 University Avenue, Room 1433, Toronto, ON, M5G 1M1, Canada
| | - Rocco Romagnuolo
- McEwen Stem Cell Institute, University Health Network, Toronto, ON, Canada
| | | | - Kyle D W Vollett
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, 661 University Avenue, Room 1433, Toronto, ON, M5G 1M1, Canada
| | - Daniel A Szulc
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, 661 University Avenue, Room 1433, Toronto, ON, M5G 1M1, Canada
| | - Hai-Ying Mary Cheng
- Department of Biology, University of Toronto Mississauga, Mississauga, ON, Canada
- Department of Cell and Systems Biology, University of Toronto, Toronto, ON, Canada
| | - Michael A Laflamme
- McEwen Stem Cell Institute, University Health Network, Toronto, ON, Canada
- Peter Munk Cardiac Centre, University Health Network, Toronto, ON, Canada
- Department of Laboratory of Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Hai-Ling Margaret Cheng
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada.
- Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, 661 University Avenue, Room 1433, Toronto, ON, M5G 1M1, Canada.
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, ON, Canada.
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Loai S, Qiang B, Laflamme MA, Cheng HLM. Blood-pool MRI assessment of myocardial microvascular reactivity. Front Cardiovasc Med 2023; 10:1216587. [PMID: 38028477 PMCID: PMC10646425 DOI: 10.3389/fcvm.2023.1216587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 10/20/2023] [Indexed: 12/01/2023] Open
Abstract
Purpose The ability to non-invasively image myocardial microvascular dilation and constriction is essential to assessing intact function and dysfunction. Yet, conventional measurements based on blood oxygenation are not specific to changes in blood volume. The purpose of this study was to extend to the heart a blood-pool MRI approach for assessing vasomodulation in the presence of blood gas changes and investigate if sex-related differences exist. Methods Animals [five male and five female healthy Sprague Dawley rats (200-500 g)] were intubated, ventilated, and cycled through room air (normoxia) and hypercapnia (10% CO2) in 10-minute cycles after i.v. injection of blood-pool agent Ablavar (0.3 mmol/kg). Pre-contrast T1 maps and T1-weighted 3D CINE were acquired on a 3 Tesla preclinical MRI scanner, followed by repeated 3D CINE every 5 min until the end of the gas regime. Invasive laser Doppler flowmetry of myocardial perfusion was performed to corroborate MRI results. Results Myocardial microvascular dilation to hypercapnia and constriction to normoxia were readily visualized on T1 maps. Over 10 min of hypercapnia, female myocardial T1 reduced by 20% (vasodilation), while no significant change was observed in the male myocardium. After return to normoxia, myocardial T1 increased (vasoconstriction) in both sexes (18% in females and 16% in males). Laser Doppler perfusion measurements confirmed vasomodulatory responses observed on MRI. Conclusion Blood-pool MRI is sensitive and specific to vasomodulation in the myocardial microcirculation. Sex-related differences exist in the healthy myocardium in response to mild hypercapnic stimuli.
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Affiliation(s)
- Sadi Loai
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON, Canada
| | - Beiping Qiang
- McEwen Stem Cell Institute, University Health Network, Toronto, ON, Canada
| | - Michael A. Laflamme
- McEwen Stem Cell Institute, University Health Network, Toronto, ON, Canada
- Peter Munk Cardiac Centre, University Health Network, Toronto, ON, Canada
- Laboratory of Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Hai-Ling Margaret Cheng
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON, Canada
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, ON, Canada
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Tawagi E, Vollett KDW, Szulc DA, Santerre JP, Cheng HLM. In Vivo MRI Tracking of Degradable Polyurethane Hydrogel Degradation In Situ Using a Manganese Porphyrin Contrast Agent. J Magn Reson Imaging 2023; 58:1139-1150. [PMID: 36877190 DOI: 10.1002/jmri.28664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 02/10/2023] [Accepted: 02/13/2023] [Indexed: 03/07/2023] Open
Abstract
BACKGROUND A noninvasive method to track implanted biomaterials is desirable for real-time monitoring of material interactions with host tissues and assessment of efficacy and safety. PURPOSE To explore quantitative in vivo tracking of polyurethane implants using a manganese porphyrin (MnP) contrast agent containing a covalent binding site for pairing to polymers. STUDY TYPE Prospective, longitudinal. ANIMAL MODEL Rodent model of dorsal subcutaneous implants (10 female Sprague Dawley rats). FIELD STRENGTH/SEQUENCE A 3-T; two-dimensional (2D) T1-weighted spin-echo (SE), T2-weighted turbo SE, three-dimensional (3D) spoiled gradient-echo T1 mapping with variable flip angles. ASSESSMENT A new MnP-vinyl contrast agent to covalently label polyurethane hydrogels was synthesized and chemically characterized. Stability of binding was assessed in vitro. MRI was performed in vitro on unlabeled hydrogels and hydrogels labeled at different concentrations, and in vivo on rats with unlabeled and labeled hydrogels implanted dorsally. In vivo MRI was performed at 1, 3, 5, and 7 weeks postimplantation. Implants were easily identified on T1-weighted SE, and fluid accumulation from inflammation was distinguished on T2-weighted turbo SE. Implants were segmented on contiguous T1-weighted SPGR slices using a threshold of 1.8 times the background muscle signal intensity; implant volume and mean T1 values were then calculated at each timepoint. Histopathology was performed on implants in the same plane as MRI and compared to imaging results. STATISTICAL TESTS Unpaired t-tests and one-way analysis of variance (ANOVA) were used for comparisons. A P value <0.05 was considered to be statistically significant. RESULTS Hydrogel labeling with MnP resulted in a significant T1 reduction in vitro (T1 = 517 ± 36 msec vs. 879 ± 147 msec unlabeled). Mean T1 values of labeled implants in rats increased significantly by 23% over time, from 1 to 7 weeks postimplantation (651 ± 49 msec to 801 ± 72 msec), indicating decreasing implant density. DATA CONCLUSION Polymer-binding MnP enables in vivo tracking of vinyl-group coupling polymers. EVIDENCE LEVEL 1. TECHNICAL EFFICACY Stage 1.
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Affiliation(s)
- Eric Tawagi
- Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, Ontario, Canada
| | - Kyle D W Vollett
- Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, Ontario, Canada
| | - Daniel A Szulc
- Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, Ontario, Canada
| | - J Paul Santerre
- Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, Ontario, Canada
- Faculty of Dentistry, University of Toronto, Toronto, Ontario, Canada
| | - Hai-Ling Margaret Cheng
- Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, Ontario, Canada
- The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, University of Toronto, Toronto, Ontario, Canada
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Tawagi E, Ung T, Cheng HLM, Santerre JP. Arrhenius-model-based degradable oligourethane hydrogels for controlled growth factor release. Acta Biomater 2023; 166:167-186. [PMID: 37207744 DOI: 10.1016/j.actbio.2023.05.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 04/22/2023] [Accepted: 05/12/2023] [Indexed: 05/21/2023]
Abstract
Biodegradable hydrogels are growing in demand to enable the delivery of biomolecules (e.g. growth factors) for regenerative medicine. This research investigated the resorption of an oligourethane/polyacrylic acid hydrogel, a biodegradable hydrogel which supports tissue regeneration. The Arrhenius model was used to characterize the resorption of the polymeric gels in relevant in vitro conditions, and the Flory-Rehner equation was used to correlate the volumetric swelling ratio with the extent of degradation. The study found that the swelling rate of the hydrogel follows the Arrhenius model at elevated temperatures, estimating degradation time in saline solution at 37°C to be between 5 and 13 months, serving as a preliminary approximation of degradation in vivo. The degradation products had low cytotoxicity towards endothelial cells, and the hydrogel supported stromal cell proliferation. Additionally, the hydrogels were able to release growth factors and maintain the biomolecules' bioactivity towards cell proliferation. The study of the vascular endothelial growth factor (VEGF) release from the hydrogel used a diffusion process model, showing that the electrostatic attraction between VEGF and the anionic hydrogel allowed for controlled and sustained VEGF release over three weeks. In a rat subcutaneous implant model, a selected hydrogel with desired degradation rates exhibited minimal foreign body response and supported M2a macrophage phenotype, and vascularization. The low M1 and high M2a macrophage phenotypes within the implants were associated with tissue integration. This research supports the use of oligourethane/polyacrylic acid hydrogels as a promising material for delivering growth factors and supporting tissue regeneration. STATEMENT OF SIGNIFICANCE: There is a need for degradable elastomeric hydrogels that can support the formation of soft tissues and minimize long-term foreign body responses. An Arrhenius model was used to estimate the relative breakdown of hydrogels, in-vitro. The results demonstrate that hydrogels made from a combination of poly(acrylic acid) and oligo-urethane diacrylates can be designed to resorb over defined periods ranging from months to years depending on the chemical formulation prescribed by the model. The hydrogel formulations also provided for different release profiles of growth factors, relevant to tissue regeneration. In-vivo, these hydrogels had minimal inflammatory effects and showed evidence of integration into the surrounding tissue. The hydrogel approach can help the field design a broader range of biomaterials for tissue regeneration.
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Affiliation(s)
- Eric Tawagi
- Institute of Biomedical Engineering, University of Toronto, 661 University Avenue, 14th Floor, Room 1435, Toronto, ON M5G 1M1, Canada; Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON, Canada
| | - Trevor Ung
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON, Canada
| | - Hai-Ling Margaret Cheng
- Institute of Biomedical Engineering, University of Toronto, 661 University Avenue, 14th Floor, Room 1435, Toronto, ON M5G 1M1, Canada; Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON, Canada; The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, University of Toronto, Toronto, ON, Canada
| | - J Paul Santerre
- Institute of Biomedical Engineering, University of Toronto, 661 University Avenue, 14th Floor, Room 1435, Toronto, ON M5G 1M1, Canada; Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON, Canada; Faculty of Dentistry, University of Toronto, Toronto, ON, Canada.
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Curtis AD, Mertens AJ, Cheng HLM. A predictive signal model for dynamic cardiac magnetic resonance imaging. Sci Rep 2023; 13:10296. [PMID: 37357251 DOI: 10.1038/s41598-023-37475-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 06/22/2023] [Indexed: 06/27/2023] Open
Abstract
Robust dynamic cardiac magnetic resonance imaging (MRI) has been a long-standing endeavor-as real-time imaging can provide information on the temporal signatures of disease we currently cannot assess-with the past decade seeing remarkable advances in acceleration using compressed sensing (CS) and artificial intelligence (AI). However, substantial limitations to real-time imaging remain and reconstruction quality is not always guaranteed. To improve reconstruction fidelity in dynamic cardiac MRI, we propose a novel predictive signal model that uses a priori statistics to adaptively predict temporal cardiac dynamics. By using a small training set obtained from the same patient, the new signal model can achieve robust dynamic cardiac MRI in the presence of irregular cardiac rhythm. Evaluation on simulated irregular cardiac dynamics and prospectively undersampled clinical cardiac MRI data demonstrate improved reconstruction quality for two reconstruction frameworks: Kalman filter and CS. The predictive model also works with different undersampling patterns (cartesian, radial, spiral) and can serve as a versatile foundation for robust dynamic cardiac MRI.
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Affiliation(s)
- Aaron D Curtis
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, Canada
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, Canada
| | - Alexander J Mertens
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, Canada
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, Canada
| | - Hai-Ling Margaret Cheng
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, Canada.
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, Canada.
- Institute of Biomedical Engineering, University of Toronto, 661 University Avenue, Room 1443, Toronto, Ontario, M5G 1M1, Canada.
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Vollett KDW, Szulc DA, Cheng HLM. A Manganese Porphyrin Platform for the Design and Synthesis of Molecular and Targeted MRI Contrast Agents. Int J Mol Sci 2023; 24:ijms24119532. [PMID: 37298480 DOI: 10.3390/ijms24119532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 05/24/2023] [Accepted: 05/29/2023] [Indexed: 06/12/2023] Open
Abstract
Magnetic resonance imaging (MRI) contrast agents, in contrast to the plethora of fluorescent agents available to target disease biomarkers or exogenous implants, have remained predominantly non-specific. That is, they do not preferentially accumulate in specific locations in vivo because doing so necessitates longer contrast retention, which is contraindicated for current gadolinium (Gd) agents. This double-edge sword implies that Gd agents can offer either rapid elimination (but lack specificity) or targeted accumulation (but with toxicity risks). For this reason, MRI contrast agent innovation has been severely constrained. Gd-free alternatives based on manganese (Mn) chelates have been largely ineffective, as they are inherently unstable. In this study, we present a Mn(III) porphyrin (MnP) platform for bioconjugation, offering the highest stability and chemical versatility compared to any other T1 contrast agent. We exploit the inherent metal stability conferred by porphyrins and the absence of pendant bases (found in Gd or Mn chelates) that limit versatile functionalization. As proof-of-principle, we demonstrate labeling of human serum albumin, a model protein, and collagen hydrogels for applications in in-vivo targeted imaging and material tracking, respectively. In-vitro and in-vivo results confirm unprecedented metal stability, ease of functionalization, and high T1 relaxivity. This new platform opens the door to ex-vivo validation by fluorescent imaging and multipurpose molecular imaging in vivo.
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Affiliation(s)
- Kyle D W Vollett
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON M5G 1M1, Canada
| | - Daniel A Szulc
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON M5G 1M1, Canada
| | - Hai-Ling Margaret Cheng
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5S 3G9, Canada
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON M5G 1M1, Canada
- The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, University of Toronto, Toronto, ON M5S 3G8, Canada
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Cheng HLM. A primer on in vivo cell tracking using MRI. Front Med (Lausanne) 2023; 10:1193459. [PMID: 37324153 PMCID: PMC10264782 DOI: 10.3389/fmed.2023.1193459] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 05/12/2023] [Indexed: 06/17/2023] Open
Abstract
Cell tracking by in vivo magnetic resonance imaging (MRI) offers a collection of multiple advantages over other imaging modalities, including high spatial resolution, unlimited depth penetration, 3D visualization, lack of ionizing radiation, and the potential for long-term cell monitoring. Three decades of innovation in both contrast agent chemistry and imaging physics have built an expansive array of probes and methods to track cells non-invasively across a diverse range of applications. In this review, we describe both established and emerging MRI cell tracking approaches and the variety of mechanisms available for contrast generation. Emphasis is given to the advantages, practical limitations, and persistent challenges of each approach, incorporating quantitative comparisons where possible. Toward the end of this review, we take a deeper dive into three key application areas - tracking cancer metastasis, immunotherapy for cancer, and stem cell regeneration - and discuss the cell tracking techniques most suitable to each.
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Affiliation(s)
- Hai-Ling Margaret Cheng
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, ON, Canada
- Ted Rogers Centre for Heart Research, Translational Biology & Engineering Program, Toronto, ON, Canada
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10
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Cheng HLM. Emerging MRI techniques for molecular and functional phenotyping of the diseased heart. Front Cardiovasc Med 2022; 9:1072828. [PMID: 36545017 PMCID: PMC9760746 DOI: 10.3389/fcvm.2022.1072828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 11/22/2022] [Indexed: 12/12/2022] Open
Abstract
Recent advances in cardiac MRI (CMR) capabilities have truly transformed its potential for deep phenotyping of the diseased heart. Long known for its unparalleled soft tissue contrast and excellent depiction of three-dimensional (3D) structure, CMR now boasts a range of unique capabilities for probing disease at the tissue and molecular level. We can look beyond coronary vessel blockages and detect vessel disease not visible on a structural level. We can assess if early fibrotic tissue is being laid down in between viable cardiac muscle cells. We can measure deformation of the heart wall to determine early presentation of stiffening. We can even assess how cardiomyocytes are utilizing energy, where abnormalities are often precursors to overt structural and functional deficits. Finally, with artificial intelligence gaining traction due to the high computing power available today, deep learning has proven itself a viable contender with traditional acceleration techniques for real-time CMR. In this review, we will survey five key emerging MRI techniques that have the potential to transform the CMR clinic and permit early detection and intervention. The emerging areas are: (1) imaging microvascular dysfunction, (2) imaging fibrosis, (3) imaging strain, (4) imaging early metabolic changes, and (5) deep learning for acceleration. Through a concerted effort to develop and translate these areas into the CMR clinic, we are committing ourselves to actualizing early diagnostics for the most intractable heart disease phenotypes.
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Affiliation(s)
- Hai-Ling Margaret Cheng
- The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada,Ted Rogers Centre for Heart Research, Translational Biology & Engineering Program, Toronto, ON, Canada,*Correspondence: Hai-Ling Margaret Cheng,
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11
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Loai S, Sun X, Husain M, Laflamme MA, Yeger H, Nunes SS, Cheng HLM. Microvascular Dysfunction in Skeletal Muscle Precedes Myocardial Vascular Changes in Diabetic Cardiomyopathy: Sex-Dependent Differences. Front Cardiovasc Med 2022; 9:886687. [PMID: 35665251 PMCID: PMC9157579 DOI: 10.3389/fcvm.2022.886687] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Accepted: 04/28/2022] [Indexed: 11/13/2022] Open
Abstract
AimTo uncover sex-related microvascular abnormalities that underlie the early presentation of reduced perfusion in leg skeletal muscle in a type II rat model of diabetic cardiomyopathy.Methods and ResultsDiabetes was induced using a non-obese, diet-based, low-dose streptozotocin model in adult female (18 diabetic, 9 control) and male rats (29 diabetic, 11 control). Time-course monitoring over 12 months following diabetes induction was performed using echocardiography, treadmill exercise, photoacoustic imaging, flow-mediated dilation (FMD), histopathology, and immunohistochemistry. Diabetic rats maintained normal weights. Hypertension appeared late in both diabetic males (7 months) and females (10 months), while only diabetic males had elevated cholesterol (7 months). On echocardiography, all diabetic animals maintained normal ejection fraction and exhibited diastolic dysfunction, mild systolic dysfunction, and a slightly enlarged left ventricle. Exercise tolerance declined progressively and early in males (4 months), later in females (8 months); FMD showed lower baseline femoral arterial flow but unchanged reactivity in both sexes (5 months); and photoacoustic imaging showed lower tissue oxygen saturation in the legs of diabetic males (4 months) and diabetic females (10 months). Myocardial perfusion was normal in both sexes. Histopathology at the final timepoint of Month 10 (males) and Month 12 (females) revealed that myocardial microvasculature was normal in both vessel density and structure, thus explaining normal perfusion on imaging. However, leg muscle microvasculature exhibited perivascular smooth muscle thickening around small arterioles in diabetic females and around large arterioles in diabetic males, explaining the depressed readings on photoacoustic and FMD. Histology also confirmed the absence of commonly reported HFpEF markers, including microvessel rarefaction, myocardial fibrosis, and left ventricular hypertrophy.ConclusionExercise intolerance manifesting early in the progression of diabetic cardiomyopathy can be attributed to decreased perfusion to the leg skeletal muscle due to perivascular smooth muscle thickening around small arterioles in females and large arterioles in males. This microvascular abnormality was absent in the myocardium, where perfusion levels remained normal throughout the study. We conclude that although skeletal muscle microvascular dysfunction of the vasculature presents at different levels depending on sex, it consistently presents early in both sexes prior to overt cardiac changes such as rarefaction, fibrosis, or hypertrophy.
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Affiliation(s)
- Sadi Loai
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON, Canada
| | - Xuetao Sun
- Toronto General Hospital Research Institute, University Health Network, Toronto, ON, Canada
| | - Mansoor Husain
- Toronto General Hospital Research Institute, University Health Network, Toronto, ON, Canada
- Peter Munk Cardiac Centre, University Health Network, Toronto, ON, Canada
- Ted Rogers Centre for Heart Research, Toronto, ON, Canada
| | - Michael A. Laflamme
- Peter Munk Cardiac Centre, University Health Network, Toronto, ON, Canada
- McEwen Stem Cell Institute, University Health Network, Toronto, ON, Canada
- Laboratory of Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Herman Yeger
- Laboratory of Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON, Canada
| | - Sara S. Nunes
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- Toronto General Hospital Research Institute, University Health Network, Toronto, ON, Canada
- Laboratory of Medicine and Pathobiology, University of Toronto, Toronto, ON, Canada
| | - Hai-Ling Margaret Cheng
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada
- Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON, Canada
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, ON, Canada
- *Correspondence: Hai-Ling Margaret Cheng
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12
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Loai S, Szulc DA, Cheng HLM. Three-Dimensional Bioprinted MR-Trackable Regenerative Scaffold for Postimplantation Monitoring on T1-Weighted MRI. J Magn Reson Imaging 2022; 56:570-578. [PMID: 34994024 DOI: 10.1002/jmri.28057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 12/22/2021] [Accepted: 12/23/2021] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND A three-dimensional (3D) bioprinted tissue scaffold is a promising therapeutic that goes beyond providing physical support for tissue regeneration by enabling precise spatial control over scaffold geometry and integration of different materials/cells. Critically important is in vivo confirmation of correct scaffold placement and retention during the initial 24 hours postimplantation, to detect unwanted implant migration. PURPOSE To incorporate a safe, efficient MR contrast agent into a bioprinting workflow, and to achieve bright-contrast scaffold monitoring in vivo postimplantation. STUDY TYPE In vitro and animal in vivo longitudinal study. ANIMAL MODEL Two female Sprague Dawley rats (~200 g) for labeled and unlabeled scaffold implantation in the subcutaneous dorsal space flanking the vertebral column. FIELD STRENGTH/SEQUENCE A 7.0 T/T1 -weighted spin echo (SE) sequence and T1 mapping using turbo SE with variable repetition times (TRs). ASSESSMENT Cell viability and proliferation were assessed over 2 weeks after labeling bioprinted gelatin/alginate scaffolds with MnPNH2 (0.5 mM, 24 hours). In vitro MRI was performed 0, 12, and 24 hours postlabeling in nine labeled and three unlabeled (control) scaffolds to monitor T1 evolution. In vivo MRI was performed immediately and 24 hours postimplantation to assess T1 . Acute inflammation near surgical site was monitored in one rat to 3 days. STATISTICAL TESTS One-way analysis of variance with Tukey-Kramer post hoc analysis (P < 0.01). RESULTS Cell viability was unaffected by bioprinting/labeling: viability exceeded 90% in all scaffolds after 1 week. In vitro T1 's were significantly lower in labeled scaffolds compared to control (207 msec vs. 2257 msec) immediately postlabeling and 24 hours later (1227 msec vs. 2257 msec). In vivo T1 's were significantly different (243.6 msec vs. 2414.6 msec) immediately postimplantation, and no differences emerged compared to respective in vitro control/labeled counterparts. The 24-hours imaging and gross pathology confirmed migration of scaffolds beyond the imaging field. DATA CONCLUSION We report an MR-detectable, cell-compatible bioprinted scaffold, utilizing a T1 -weighting contrast agent for high-resolution, postimplantation scaffold tracking. EVIDENCE LEVEL 2 TECHNICAL EFFICACY: Stage 1.
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Affiliation(s)
- Sadi Loai
- Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada.,Ted Rogers Centre for Heart Research, Translational Biology & Engineering Program, Toronto, Ontario, Canada
| | - Daniel A Szulc
- Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada.,Ted Rogers Centre for Heart Research, Translational Biology & Engineering Program, Toronto, Ontario, Canada
| | - Hai-Ling Margaret Cheng
- Institute of Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada.,Ted Rogers Centre for Heart Research, Translational Biology & Engineering Program, Toronto, Ontario, Canada.,The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, Ontario, Canada
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13
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Mokhtari RB, Qorri B, Baluch N, Sparaneo A, Fabrizio FP, Muscarella LA, Tyker A, Kumar S, Cheng HLM, Szewczuk MR, Das B, Yeger H. Correction: Next-generation multimodality of nutrigenomic cancer therapy: sulforaphane in combination with acetazolamide actively target bronchial carcinoid cancer in disabling the PI3K/Akt/mTOR survival pathway and inducing apoptosis. Oncotarget 2022; 13:968-969. [PMID: 36093295 PMCID: PMC9450989 DOI: 10.18632/oncotarget.28104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Affiliation(s)
- Reza Bayat Mokhtari
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Experimental Therapeutics, Thoreau Laboratory for Global Health, M2D2, University of Massachusetts, Lowell, MA, USA
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, Ontario, Canada
| | - Bessi Qorri
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, Ontario, Canada
| | - Narges Baluch
- Department of Immunology and Allergy, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Angelo Sparaneo
- Laboratory of Oncology, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo FG, Italy
| | - Federico Pio Fabrizio
- Laboratory of Oncology, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo FG, Italy
| | - Lucia Anna Muscarella
- Laboratory of Oncology, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo FG, Italy
| | - Albina Tyker
- Department of Internal Medicine, University of Chicago, Chicago, IL, USA
| | - Sushil Kumar
- Q.P.S. Holdings LLC, Pencader Corporate Center, Newark, DE, USA
| | - Hai-Ling Margaret Cheng
- Institute of Biomedical Engineering, The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, University of Toronto, Toronto, Canada
| | - Myron R. Szewczuk
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, Ontario, Canada
| | - Bikul Das
- Department of Experimental Therapeutics, Thoreau Laboratory for Global Health, M2D2, University of Massachusetts, Lowell, MA, USA
- Department of Cancer and Stem Cell Biology, KaviKrishna Laboratory, Guwahati Biotech Park, Indian Institute of Technology, Guwahati, Assam, India
- Department of Immunology and Infectious Diseases, Forsyth Institute, Cambridge, MA, USA
| | - Herman Yeger
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario, Canada
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14
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Troy AM, Cheng HLM. Corrigendum: Human microvascular reactivity: a review of vasomodulating stimuli and non-invasive imaging assessment (2021 Physiol. Meas.4209TR01). Physiol Meas 2021; 42. [PMID: 34842178 DOI: 10.1088/1361-6579/ac304d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 10/15/2021] [Indexed: 11/11/2022]
Affiliation(s)
- Aaron M Troy
- Institute of Biomedical Engineering, University of Toronto, Canada.,Ted Rogers Centre for Heart Research, Translational Biology & Engineering Program, Toronto, Canada.,Cardiovascular Sciences Collaborative Specialization, University of Toronto, Canada
| | - Hai-Ling Margaret Cheng
- Institute of Biomedical Engineering, University of Toronto, Canada.,Ted Rogers Centre for Heart Research, Translational Biology & Engineering Program, Toronto, Canada.,Cardiovascular Sciences Collaborative Specialization, University of Toronto, Canada.,The Edward S. Rogers Sr Department of Electrical and Computer Engineering, University of Toronto, Canada.,Heart & Stroke/Richard Lewar Centre of Excellence for Cardiovascular Research, Toronto, Canada.,Ontario Institute for Regenerative Medicine, Toronto, Canada
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15
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Loai S, Zhou YQ, Vollett KDW, Cheng HLM. Skeletal Muscle Microvascular Dysfunction Manifests Early in Diabetic Cardiomyopathy. Front Cardiovasc Med 2021; 8:715400. [PMID: 34355034 PMCID: PMC8329089 DOI: 10.3389/fcvm.2021.715400] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 06/28/2021] [Indexed: 12/03/2022] Open
Abstract
Aim: To perform a deep cardiac phenotyping of type II diabetes in a rat model, with the goal of gaining new insight into the temporality of microvascular dysfunction, cardiac dysfunction, and exercise intolerance at different stages of diabetes. Methods and Results: Diabetes was reproduced using a non-obese, diet-based, low-dose streptozotocin model in male rats (29 diabetic, 11 control). Time-course monitoring over 10 months was performed using echocardiography, treadmill exercise, photoacoustic perfusion imaging in myocardial and leg skeletal muscle, flow-mediated dilation, blood panel, and histology. Diabetic rats maintained a normal weight throughout. At early times (4 months), a non-significant reduction (30%) emerged in skeletal muscle perfusion and in exercise tolerance. At the same time, diabetic rats had a normal, slightly lower ejection fraction (63 vs. 71% control, p < 0.01), grade 1 diastolic dysfunction (E/A = 1.1 vs. 1.5, isovolumetric relaxation time = 34 vs. 27 ms; p < 0.01), mild systolic dysfunction (ejection time = 69 vs. 57 ms, isovolumetric contraction time = 21 vs. 17 ms; p < 0.01), and slightly enlarged left ventricle (8.3 vs. 7.6 mm diastole; p < 0.01). Diastolic dysfunction entered grade 3 at Month 8 (E/A = 1.7 vs. 1.3, p < 0.05). Exercise tolerance remained low in diabetic rats, with running distance declining by 60%; in contrast, control rats ran 60% farther by Month 5 (p < 0.05) and always remained above baseline. Leg muscle perfusion remained low in diabetic rats, becoming significantly lower than control by Month 10 (33% SO2 vs. 57% SO2, p < 0.01). Myocardial perfusion remained normal throughout. Femoral arterial reactivity was normal, but baseline velocity was 25% lower than control (p < 0.05). High blood pressure appeared late in diabetes (8 months). Histology confirmed absence of interstitial fibrosis, cardiomyocyte hypertrophy, or microvascular rarefaction in the diabetic heart. Rarefaction was also absent in leg skeletal muscle. Conclusion: Reduced skeletal muscle perfusion from microvascular dysfunction emerged early in diabetic rats, but myocardial perfusion remained normal throughout the study. At the same time, diabetic rats exhibited exercise intolerance and early cardiac dysfunction, in which changes related to heart failure with preserved ejection fraction (HFpEF) were seen. Importantly, skeletal muscle microvascular constriction advanced significantly before the late appearance of hypertension. HFpEF phenotypes such as cardiac hypertrophy, fibrosis, and rarefaction, which are typically associated with hypertension, were absent over the 10 month time-course of diabetes-related heart failure.
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Affiliation(s)
- Sadi Loai
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada.,Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON, Canada
| | - Yu-Qing Zhou
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada.,Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON, Canada
| | - Kyle D W Vollett
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada.,Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON, Canada
| | - Hai-Ling Margaret Cheng
- Institute of Biomedical Engineering, University of Toronto, Toronto, ON, Canada.,Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, Toronto, ON, Canada.,The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, ON, Canada
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16
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Mokhtari RB, Qorri B, Baluch N, Sparaneo A, Fabrizio FP, Muscarella LA, Tyker A, Kumar S, Cheng HLM, Szewczuk MR, Das B, Yeger H. Next-generation multimodality of nutrigenomic cancer therapy: sulforaphane in combination with acetazolamide actively target bronchial carcinoid cancer in disabling the PI3K/Akt/mTOR survival pathway and inducing apoptosis. Oncotarget 2021; 12:1470-1489. [PMID: 34316328 PMCID: PMC8310668 DOI: 10.18632/oncotarget.28011] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2021] [Accepted: 06/14/2021] [Indexed: 11/25/2022] Open
Abstract
OBJECTIVE Aberrations in the PI3K/AKT/mTOR survival pathway in many cancers are the most common genomic abnormalities. The phytochemical and bioactive agent sulforaphane (SFN) has nutrigenomic potential in activating the expression of several cellular protective genes via the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2). Nrf2 is primarily related to mechanisms of endogenous cellular defense and survival. The efficacy of SFN in combination with acetazolamide (AZ) was investigated in reducing typical H727 and atypical H720 BC survival, migration potential, and apoptosis in vitro and in vivo preclinical xenograft tissues. MATERIALS AND METHODS Microscopic imaging, immunocytochemistry, wound healing assay, caspase-cleaved cytokeratin 18 (M30, CCK18) CytoDeath ELISA assay, immunofluorescence labeling assays for apoptosis, hypoxia, Western Blotting, Tunnel assay, measurement of 5-HT secretion by carbon fiber amperometry assay, quantitative methylation-specific PCR (qMSP), morphologic changes, cell viability, apoptosis activity and the expression levels of phospho-Akt1, Akt1, HIF-1α, PI3K, p21, CAIX, 5-HT, phospho-mTOR, and mTOR in xenografts derived from typical H727 and atypical H720 BC cell lines. RESULTS Combining AZ+SFN reduced tumor cell survival compared to each agent alone, both in vitro and in vivo xenograft tissues. AZ+SFN targeted multiple pathways involved in cell cycle, serotonin secretion, survival, and growth pathways, highlighting its therapeutic approach. Both H727 and H720 cells were associated with induction of apoptosis, upregulation of the p21 cell cycle inhibitor, and downregulation of the PI3K/Akt/mTOR pathway, suggesting that the PI3K/Akt/mTOR pathway is a primary target of the AZ+SFN combination therapy. CONCLUSIONS Combining SFN+AZ significantly inhibits the PI3K/Akt/mTOR pathway and significantly reducing 5-HT secretion in carcinoid syndrome.
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Affiliation(s)
- Reza Bayat Mokhtari
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario, Canada.,Department of Experimental Therapeutics, Thoreau Laboratory for Global Health, M2D2, University of Massachusetts, Lowell, MA, USA.,Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Bessi Qorri
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Narges Baluch
- Department of Immunology and Allergy, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Angelo Sparaneo
- Laboratory of Oncology, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo FG, Italy
| | - Federico Pio Fabrizio
- Laboratory of Oncology, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo FG, Italy
| | - Lucia Anna Muscarella
- Laboratory of Oncology, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo FG, Italy
| | - Albina Tyker
- Department of Internal Medicine, University of Chicago, Chicago, IL, USA
| | - Sushil Kumar
- Q.P.S. Holdings LLC, Pencader Corporate Center, Newark, DE, USA
| | - Hai-Ling Margaret Cheng
- Institute of Biomedical Engineering, The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, University of Toronto, Toronto, Canada
| | - Myron R Szewczuk
- Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada
| | - Bikul Das
- Department of Experimental Therapeutics, Thoreau Laboratory for Global Health, M2D2, University of Massachusetts, Lowell, MA, USA.,Department of Cancer and Stem Cell Biology, KaviKrishna Laboratory, Guwahati Biotech Park, Indian Institute of Technology, Guwahati, Assam, India.,Department of Immunology and Infectious Diseases, Forsyth Institute, Cambridge, MA, USA
| | - Herman Yeger
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario, Canada
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17
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Mokhtari RB, Sambi M, Qorri B, Baluch N, Ashayeri N, Kumar S, Cheng HLM, Yeger H, Das B, Szewczuk MR. The Next-Generation of Combination Cancer Immunotherapy: Epigenetic Immunomodulators Transmogrify Immune Training to Enhance Immunotherapy. Cancers (Basel) 2021; 13:3596. [PMID: 34298809 PMCID: PMC8305317 DOI: 10.3390/cancers13143596] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/13/2021] [Accepted: 07/14/2021] [Indexed: 12/12/2022] Open
Abstract
Cancer immunotherapy harnesses the immune system by targeting tumor cells that express antigens recognized by immune system cells, thus leading to tumor rejection. These tumor-associated antigens include tumor-specific shared antigens, differentiation antigens, protein products of mutated genes and rearrangements unique to tumor cells, overexpressed tissue-specific antigens, and exogenous viral proteins. However, the development of effective therapeutic approaches has proven difficult, mainly because these tumor antigens are shielded, and cells primarily express self-derived antigens. Despite innovative and notable advances in immunotherapy, challenges associated with variable patient response rates and efficacy on select tumors minimize the overall effectiveness of immunotherapy. Variations observed in response rates to immunotherapy are due to multiple factors, including adaptative resistance, competency, and a diversity of individual immune systems, including cancer stem cells in the tumor microenvironment, composition of the gut microbiota, and broad limitations of current immunotherapeutic approaches. New approaches are positioned to improve the immune response and increase the efficacy of immunotherapies, highlighting the challenges that the current global COVID-19 pandemic places on the present state of immunotherapy.
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Affiliation(s)
- Reza Bayat Mokhtari
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, ON K7L 3N6, Canada; (M.S.); (B.Q.)
- Department of Experimental Therapeutics, Thoreau Laboratory for Global Health, M2D2, University of Massachusetts, Lowell, MA 01852, USA;
| | - Manpreet Sambi
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, ON K7L 3N6, Canada; (M.S.); (B.Q.)
| | - Bessi Qorri
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, ON K7L 3N6, Canada; (M.S.); (B.Q.)
| | - Narges Baluch
- Department of Immunology and Allergy, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada;
| | - Neda Ashayeri
- Division of Hematology & Oncology, Department of Pediatrics, Ali-Asghar Children Hospital, Iran University of Medical Science, Tehran 1449614535, Iran;
| | - Sushil Kumar
- QPS, Holdings LLC, Pencader Corporate Center, 110 Executive Drive, Newark, DE 19702, USA;
| | - Hai-Ling Margaret Cheng
- The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, Institute of Biomedical Engineering, University of Toronto, Toronto, ON M5G 1M1, Canada;
- Translational Biology & Engineering Program, Ted Rogers Centre for Heart Research, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Herman Yeger
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, ON M5G 0A4, Canada;
| | - Bikul Das
- Department of Experimental Therapeutics, Thoreau Laboratory for Global Health, M2D2, University of Massachusetts, Lowell, MA 01852, USA;
- KaviKrishna Laboratory, Department of Cancer and Stem Cell Biology, GBP, Indian Institute of Technology, Guwahati 781039, India
| | - Myron R. Szewczuk
- Department of Biomedical and Molecular Sciences, Queen’s University, Kingston, ON K7L 3N6, Canada; (M.S.); (B.Q.)
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Szulc DA, Lee XA, Cheng HYM, Cheng HLM. Bright Ferritin-a Reporter Gene Platform for On-Demand, Longitudinal Cell Tracking on MRI. iScience 2020; 23:101350. [PMID: 32707432 PMCID: PMC7381694 DOI: 10.1016/j.isci.2020.101350] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 06/14/2020] [Accepted: 07/03/2020] [Indexed: 02/02/2023] Open
Abstract
A major unresolved challenge in cell-based regenerative medicine is the absence of non-invasive technologies for tracking cell fate in deep tissue and with high spatial resolution over an extended interval. MRI is highly suited for this task, but current methods fail to provide longitudinal monitoring or high sensitivity, or both. In this study, we fill this technological gap with the first discovery and demonstration of in vivo cellular production of endogenous bright contrast via an MRI genetic reporter system that forms manganese-ferritin nanoparticles. We demonstrate this technology in human embryonic kidney cells genetically modified to stably overexpress ferritin and show that, in the presence of manganese, these cells produce far greater contrast than conventional ferritin overexpression with iron or manganese-permeable cells. In living mice, diffusely implanted bright-ferritin cells produce the highest and most sustained contrast in skeletal muscle. The bright-ferritin platform has potential for on-demand, longitudinal, and sensitive cell tracking in vivo.
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Affiliation(s)
- Daniel A Szulc
- Institute of Biomedical Engineering, University of Toronto, 164 College Street, RS407, Toronto, ON M5S 3G9, Canada; Ted Rogers Centre for Heart Research, Translational Biology & Engineering Program, University of Toronto, Toronto, ON M5G 1M1, Canada
| | - Xavier A Lee
- Ted Rogers Centre for Heart Research, Translational Biology & Engineering Program, University of Toronto, Toronto, ON M5G 1M1, Canada; Department of Physiology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Hai-Ying Mary Cheng
- Department of Biology, University of Toronto Mississauga, Mississauga, ON L5L 1C6, Canada
| | - Hai-Ling Margaret Cheng
- Institute of Biomedical Engineering, University of Toronto, 164 College Street, RS407, Toronto, ON M5S 3G9, Canada; Ted Rogers Centre for Heart Research, Translational Biology & Engineering Program, University of Toronto, Toronto, ON M5G 1M1, Canada; The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, University of Toronto, Toronto, ON M5S 3G4, Canada.
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19
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Szulc DA, Ahmadipour M, Aoki FG, Waddell TK, Karoubi G, Cheng HLM. MRI method for labeling and imaging decellularized extracellular matrix scaffolds for tissue engineering. Magn Reson Med 2019; 83:2138-2149. [PMID: 31729091 DOI: 10.1002/mrm.28072] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Revised: 10/15/2019] [Accepted: 10/20/2019] [Indexed: 11/08/2022]
Abstract
PURPOSE To develop a facile method for labeling and imaging decellularized extracellular matrix (dECM) scaffolds intended for regenerating 3D tissues. METHODS A small molecule manganese porphyrin, MnPNH2 , was synthesized and used to label dECM scaffolds made from porcine bladder and trachea and murine whole lungs. The labeling protocol was optimized on bladder dECM, and imaging on a 3T clinical scanner was performed to assess reductions in T1 and T2 relaxation times. In vivo MRI was performed on dECM injected in the rat dorsum to verify sensitivity of detection. Toxicity assays for cell viability, metabolism, and proliferation were performed on human umbilical vein endothelial cells. The incorporation of MnPNH2 and its long-term retention in dECM were assessed on transmission electron microscopy and ultraviolet absorbance of eluted MnPNH2 over time. RESULTS All tissues, including thick whole 3D organs, were uniformly labeled and demonstrated high signal-to-noise on MRI. A nearly 10-fold reduction in T1 was consistently obtained at a labeling dose of 0.4 mM, and even 0.2 mM provided sufficient contrast in vivo and ex vivo. No toxicity was observed up to 0.4 mM, the maximum tested. Binding studies suggested nonspecific association, and retention studies in the labeled whole decellularized lungs revealed less than 20% MnPNH2 loss over 30 days, the majority occurring in the first 3 days after labeling. CONCLUSION The proposed labeling method is the first report for visualizing dECM on MRI and has the potential for long-term monitoring and optimization of dECM-based organ tissue engineering.
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Affiliation(s)
- Daniel Andrzej Szulc
- Institute of Biomaterials & Biomedical Engineering, University of Toronto, Canada.,Ted Rogers Centre for Heart Research, Translational Biology & Engineering Program, Toronto, Canada
| | - Mohammadali Ahmadipour
- Institute of Biomaterials & Biomedical Engineering, University of Toronto, Canada.,Latner Thoracic Surgery Laboratories, Toronto General Hospital Research Institute, University Health Network, Toronto, Canada
| | - Fabio Gava Aoki
- Latner Thoracic Surgery Laboratories, Toronto General Hospital Research Institute, University Health Network, Toronto, Canada
| | - Thomas K Waddell
- Institute of Biomaterials & Biomedical Engineering, University of Toronto, Canada.,Latner Thoracic Surgery Laboratories, Toronto General Hospital Research Institute, University Health Network, Toronto, Canada.,Department of Mechanical and Industrial Engineering, University of Toronto, Canada
| | - Golnaz Karoubi
- Latner Thoracic Surgery Laboratories, Toronto General Hospital Research Institute, University Health Network, Toronto, Canada.,Department of Mechanical and Industrial Engineering, University of Toronto, Canada.,Ontario Institute for Regenerative Medicine, Toronto, Canada
| | - Hai-Ling Margaret Cheng
- Institute of Biomaterials & Biomedical Engineering, University of Toronto, Canada.,Ted Rogers Centre for Heart Research, Translational Biology & Engineering Program, Toronto, Canada.,Ontario Institute for Regenerative Medicine, Toronto, Canada.,Heart & Stroke/Richard Lewar Centre of Excellence for Cardiovascular Research, Toronto, Canada.,The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Canada
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Tawagi E, Ganesh T, Cheng HLM, Santerre JP. Synthesis of degradable-polar-hydrophobic-ionic co-polymeric microspheres by membrane emulsion photopolymerization: In vitro and in vivo studies. Acta Biomater 2019; 89:279-288. [PMID: 30853610 DOI: 10.1016/j.actbio.2019.03.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 02/21/2019] [Accepted: 03/06/2019] [Indexed: 12/12/2022]
Abstract
The synthesis of microspheres for tissue regeneration requires good control over the particle size and size distribution. This is particularly important when considering the immune response that may be triggered by the presence of particles in tissue. This report outlines the design of an injectable microsphere system using a low-inflammatory, degradable-polar-hydrophobic-ionic polyurethane, termed D-PHI, and investigates the system's performance in vitro and in vivo. Crosslinked polyurethane microspheres were prepared via a rapid and controlled process based on membrane emulsion and subsequent photopolymerization. The fabrication process efficiently generated microspheres with a narrow size distribution (12 ± 2 μm, PDI = 0.03). The D-PHI microspheres exhibited a slow and controlled degradation and a high capacity for water uptake. Water within the particles existed primarily within the pores of the particles and to a lesser degree within the polymer matrix itself. D-PHI microspheres supported human endothelial and fibroblast cell growth, and they maintained human blood-derived monocytes in a low-inflammatory state. Sub-acute toxicity was assessed for the particles after being administered via intramuscular injection in the gastrocnemius muscle of rats. Cellular infiltration and vascularization into the tissue region where the particles were deposited were observed along with an absence of a fibrous capsule around the particles. The microspheres did not cause elevated human monocyte induced inflammatory character, and supported tissue integration without a prolonged inflammatory response in the rat muscle. These injectable, degradable and low-inflammatory microspheres provide an attractive system for potential drug delivery and tissue regeneration applications in future studies. STATEMENT OF SIGNIFICANCE: Biodegradable, synthetic polymers are attractive candidates for generating tailored drug delivery vehicles and tissue scaffolds owing to their diverse chemical and physical properties that can be customised for delivering defined macromolecules at specific sites in the body. The past two decades have yielded interesting work exploring the fabrication of polymer microspheres with a narrow size distribution. However, the markedly low number of synthetic polymer chemistries currently used for microsphere production exhibit elevated proinflammatory character, both acute and chronic. Furthermore, a limited number of studies have explored the biocompatibility and immune response of polymeric microspheres with human primary cells and in vivo. In the current study, a method was conceived for efficiently generating low-activating polyurethane microspheres with respect to in vitro monocytes and in vivo macrophages. The biodegradable polyurethane, which contained multiple chemistry function and which has previously demonstrated anti-inflammatory properties in film and mm scale scaffold form, was selected as the base material. In this work we undertook the use of a room temperature membrane emulsification photopolymerization approach to avoid the need for high temperature cures and the use of solvents. The response of immune cells to the microspheres was studied with human primary cells and in the rat gastrocnemius muscle. The present work reveals important progress in the design of microspheres, with well-characterized low monocyte-activating properties and the translational advantages of a synthetic polyurethane which could be investigated in future studies for potential macromolecule delivery and tissue regeneration applications.
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Szulc DA, Cheng HLM. One-Step Labeling of Collagen Hydrogels with Polydopamine and Manganese Porphyrin for Non-Invasive Scaffold Tracking on Magnetic Resonance Imaging. Macromol Biosci 2019; 19:e1800330. [PMID: 30645045 DOI: 10.1002/mabi.201800330] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 11/29/2018] [Indexed: 11/09/2022]
Abstract
Biomaterial scaffolds are the cornerstone to supporting 3D tissue growth. Optimized scaffold design is critical to successful regeneration, and this optimization requires accurate knowledge of the scaffold's interaction with living tissue in the dynamic in vivo milieu. Unfortunately, non-invasive methods that can probe scaffolds in the intact living subject are largely underexplored, with imaging-based assessment relying on either imaging cells seeded on the scaffold or imaging scaffolds that have been chemically altered. In this work, the authors develop a broadly applicable magnetic resonance imaging (MRI) method to image scaffolds directly. A positive-contrast "bright" manganese porphyrin (MnP) agent for labeling scaffolds is used to achieve high sensitivity and specificity, and polydopamine, a biologically derived universal adhesive, is employed for adhering the MnP. The technique was optimized in vitro on a prototypic collagen gel, and in vivo assessment was performed in rats. The results demonstrate superior in vivo scaffold visualization and the potential for quantitative tracking of degradation over time. Designed with ease of synthesis in mind and general applicability for the continuing expansion of available biomaterials, the proposed method will allow tissue engineers to assess and fine-tune the in vivo behavior of their scaffolds for optimal regeneration.
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Affiliation(s)
- Daniel Andrzej Szulc
- Institute of Biomaterials & Biomedical Engineering, The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, Ted Rogers Centre for Heart Research, Translational Biology & Engineering Program, University of Toronto, 164 College Street, RS407, Toronto, ON, M5S 3G9, Canada
| | - Hai-Ling Margaret Cheng
- Institute of Biomaterials & Biomedical Engineering, The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, Ted Rogers Centre for Heart Research, Translational Biology & Engineering Program, University of Toronto, 164 College Street, RS407, Toronto, ON, M5S 3G9, Canada
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Alhamami M, Cheng W, Lyu Y, Allen C, Zhang XA, Cheng HLM. Manganese-porphyrin-enhanced MRI for the detection of cancer cells: A quantitative in vitro investigation with multiple clinical subtypes of breast cancer. PLoS One 2018; 13:e0196998. [PMID: 29795583 PMCID: PMC5993062 DOI: 10.1371/journal.pone.0196998] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Accepted: 04/24/2018] [Indexed: 01/26/2023] Open
Abstract
Magnetic resonance imaging (MRI) contrast agents (CAs) are chemical compounds that can enhance image contrast on T1- or T2- weighted MR image. We have previously demonstrated the potential of MnCl2, a manganese-based CA, in cellular imaging of breast cancer using T1-weighted MRI. In this work, we examined the potential of another class of manganese-based CAs, manganese porphyrins (MnPs), for sensitive cellular detection of multiple clinical subtypes of breast cancer using quantitative MRI. Using a clinical 3.0-T MRI scanner, the relaxivities of two MnPs, MnTPPS4 and MnTPPS3NH2, and conventional Gd-DTPA (control) were measured in ultrapure water and their T1 contrast enhancement patterns were characterized in multiple clinical subtypes of breast cancer. The toxicity of the three CAs was evaluated in vitro. Compared to Gd-DTPA, both MnTPPS3NH2 and MnTPPS4 enabled a more sensitive multi-subtype detection of four breast cell lines at doses that posed no cytotoxic effects, with MnTPPS3NH2 producing the greatest positive enhancement. The superior T1 enhancement capabilities of MnPs over Gd-DTPA are statistically significant and are likely due to their greater cellular uptake and relaxivities. The results demonstrate that multiple clinical subtypes of breast cancer can be imaged on a 3.0-T MRI scanner using MnPs as T1 cellular CAs.
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Affiliation(s)
- Mosa Alhamami
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
- Translational Medicine, Hospital for Sick Children Research Institute, Toronto, Ontario, Canada
| | - Weiran Cheng
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto, Ontario, Canada
| | - Yuanyuan Lyu
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto, Ontario, Canada
- School of Medicine, Zhejiang University City College, Hangzhou, Zhejiang, P. R. China
| | - Christine Allen
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
- Spatio-Temporal Targeting and Amplification of Radiation Response (STTARR) Innovation Centre, Radiation Medicine Program, Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
| | - Xiao-an Zhang
- Department of Chemistry, University of Toronto, Toronto, Ontario, Canada
- Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto, Ontario, Canada
- Department of Biological Sciences, University of Toronto Scarborough, Toronto, Ontario, Canada
| | - Hai-Ling Margaret Cheng
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
- Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
- Translational Medicine, Hospital for Sick Children Research Institute, Toronto, Ontario, Canada
- The Edward S. Rogers Sr. Department of Electrical and Computer Engineering, University of Toronto, Toronto, Ontario, Canada
- Translational Biology and Engineering Program, Ted Rogers Centre for Heart Research, Toronto, Ontario, Canada
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Nofiele JT, Czarnota GJ, Cheng HLM. Noninvasive manganese-enhanced magnetic resonance imaging for early detection of breast cancer metastatic potential. Mol Imaging 2014; 13. [PMID: 24622809 DOI: 10.2310/7290.2013.00071] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cancer cells with a high metastatic potential will more likely escape and form distant tumors. Once the cancer has spread, a cure is rarely possible. Unfortunately, metastasis often proceeds unnoticed until a secondary tumor has formed. The culprit is that current imaging-based cancer screening and diagnosis are limited to assessing gross physical changes, not the earliest cellular changes that drive cancer progression. The purpose of this study is to develop a novel noninvasive magnetic resonance (MR) cellular imaging capability for characterizing the metastatic potential of breast cancer and enable early cancer detection. This MR method relies on imaging cell uptake of manganese, an endogenous calcium analogue and an MR contrast agent, to detect aggressive cancer cells. Studies on normal breast epithelial cells and three breast cancer cell lines, from nonmetastatic to highly metastatic, demonstrated that aggressive cancer cells appeared significantly brighter on MR as a result of altered cell uptake of manganese. In vivo results in nude rats showed that aggressive tumors that are otherwise unseen on conventional gadolinium-enhanced MR imaging are detected after manganese injection. This cellular MR imaging technology brings a critically needed, unique dimension to cancer imaging by enabling us to identify and characterize metastatic cancer cells at their earliest appearance.
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Nofiele JT, Cheng W, Haedicke IE, Ganesh T, Zhang XA, Cheng HLM. Ultrashort Echo Time Magnetic Resonance Imaging of the Lung Using a High-Relaxivity T1Blood-Pool Contrast Agent. Mol Imaging 2014; 13. [DOI: 10.2310/7290.2014.00027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Joris Tchouala Nofiele
- From The Institute of Biomaterials & Biomedical Engineering, The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, Departments of Medical Biophysics and Chemistry, Leslie Dan Faculty of Pharmacy, University of Toronto; Departments of Physical and Environmental Sciences and Biological Sciences, University of Toronto Scarborough; and SickKids Research Institute, The Hospital for Sick Children, Toronto, ON
| | - Weiran Cheng
- From The Institute of Biomaterials & Biomedical Engineering, The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, Departments of Medical Biophysics and Chemistry, Leslie Dan Faculty of Pharmacy, University of Toronto; Departments of Physical and Environmental Sciences and Biological Sciences, University of Toronto Scarborough; and SickKids Research Institute, The Hospital for Sick Children, Toronto, ON
| | - Inga E. Haedicke
- From The Institute of Biomaterials & Biomedical Engineering, The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, Departments of Medical Biophysics and Chemistry, Leslie Dan Faculty of Pharmacy, University of Toronto; Departments of Physical and Environmental Sciences and Biological Sciences, University of Toronto Scarborough; and SickKids Research Institute, The Hospital for Sick Children, Toronto, ON
| | - Tameshwar Ganesh
- From The Institute of Biomaterials & Biomedical Engineering, The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, Departments of Medical Biophysics and Chemistry, Leslie Dan Faculty of Pharmacy, University of Toronto; Departments of Physical and Environmental Sciences and Biological Sciences, University of Toronto Scarborough; and SickKids Research Institute, The Hospital for Sick Children, Toronto, ON
| | - Xiao-an Zhang
- From The Institute of Biomaterials & Biomedical Engineering, The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, Departments of Medical Biophysics and Chemistry, Leslie Dan Faculty of Pharmacy, University of Toronto; Departments of Physical and Environmental Sciences and Biological Sciences, University of Toronto Scarborough; and SickKids Research Institute, The Hospital for Sick Children, Toronto, ON
| | - Hai-Ling Margaret Cheng
- From The Institute of Biomaterials & Biomedical Engineering, The Edward S. Rogers Sr. Department of Electrical & Computer Engineering, Departments of Medical Biophysics and Chemistry, Leslie Dan Faculty of Pharmacy, University of Toronto; Departments of Physical and Environmental Sciences and Biological Sciences, University of Toronto Scarborough; and SickKids Research Institute, The Hospital for Sick Children, Toronto, ON
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Mokhtari RB, Islam SS, Baluch N, Aitken K, Kumar S, Cheng HLM, Yazdanpanah M, Adeli K, Zhou Y, Cutz E, Yeger H. Abstract 3133: The anti-tumor effects of acetazolamide and sulforaphane on bronchial carcinoids: Preclinical modeling and mechanism. Cancer Res 2014. [DOI: 10.1158/1538-7445.am2014-3133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: The prognosis of patients with metastatic bronchial carcinoid remains poor despite current conventional and targeted therapies. Here we evaluated the therapeutic potential of acetazolamide (AZ; a pan carbonic anhydrase inhibitor affecting pH regulation and homeostasis) and sulforaphane (SFN; a natural isothiocyanate compound targeting multiple pathways in cancer cells), for their anti-cancer properties. Methods: In vitro and in vivo studies were conducted on H-727 (typical carcinoid) and H-720 (atypical carcinoid) bronchial carcinoid cell lines. We developed a lung orthotopic bronchial carcinoid tumor xenograft model in NOD/SCID mice. Results: AZ and/or SFN significantly inhibited cell viability and clonogenic capacity in a dose-dependent manner (0-80 μM, 48 hours and 7 days). AZ and/or SFN downregulated phosphoH3, Ki67, EPCAM, CA9, Akt1 and upregulated p21 and Nrf2 proteins compared to controls as confirmed by Western blot. Upregulation of Nrf2 gene expression was confirmed by qPCR. AZ and/or SFN significantly reduced xenograft growth and serotonin content after two weeks treatment. In the lung orthotopic model, MR imaging at 3 Tesla precisely identified growth of H-727 injected cells in the ipsilateral side, and revealed liver metastasis as confirmed by histology. A tumor initiating cell (TIC) fraction isolated under stem cell culture conditions showing significantly enhanced tumorigenicity was also studied. Conclusions: AZ and/or SFN inhibited tumor survival, proliferation, invasiveness, serotonin secretion and tumorigenic potential of bronchial carcinoid cell lines. Since the combination of AZ+SFN was more effective than either single agent, we postulate that AZ potentiates the effects of SFN by inhibiting PI3K/AKT, which could enhance the inhibitory effect of SFN on P21, Ki67 and phosphoH3. Interestingly, Nrf2 upregulation by both AZ and by SFN suggested a potent antioxidant response. The lung orthotopic tumor model of bronchial carcinoids permits study of carcinoid metastatic progression. As the doses used in this study are clinically bioavailable we suggest that AZ and SFN may have promising potential for carcinoid therapy and resolution of the carcinoid syndrome.
Citation Format: Reza Bayat Mokhtari, Syed S. Islam, Narges Baluch, Karen Aitken, Sushil Kumar, Hai-Ling Margaret Cheng, Mehrdad Yazdanpanah, Khosrow Adeli, Yuanxiang Zhou, Ernest Cutz, Herman Yeger. The anti-tumor effects of acetazolamide and sulforaphane on bronchial carcinoids: Preclinical modeling and mechanism. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3133. doi:10.1158/1538-7445.AM2014-3133
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Affiliation(s)
| | - Syed S. Islam
- 2Hospital for Sick Children, Toronto, Ontario, Canada
| | - Narges Baluch
- 1University of Toronto Hospital for Sick Children, Toronto, Ontario, Canada
| | - Karen Aitken
- 1University of Toronto Hospital for Sick Children, Toronto, Ontario, Canada
| | - Sushil Kumar
- 1University of Toronto Hospital for Sick Children, Toronto, Ontario, Canada
| | | | | | - Khosrow Adeli
- 1University of Toronto Hospital for Sick Children, Toronto, Ontario, Canada
| | - Yuanxiang Zhou
- 1University of Toronto Hospital for Sick Children, Toronto, Ontario, Canada
| | - Ernest Cutz
- 1University of Toronto Hospital for Sick Children, Toronto, Ontario, Canada
| | - Herman Yeger
- 1University of Toronto Hospital for Sick Children, Toronto, Ontario, Canada
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Mokhtari RB, Nofiele JT, Islam SS, Yeger H, Cheng HLM. Abstract 1220: Investigation of the biological properties of human breast cancer in a nude rat model. Cancer Res 2014. [DOI: 10.1158/1538-7445.am2014-1220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Developing imaging technology for cancer diagnosis and treatment monitoring is best performed on larger pre-clinical animal models recapitulating tumor growth and metastasis more similar to that found in humans. Such models are amenable to morphological and functional imaging techniques at spatial resolutions appropriate for animal imaging and, translatable to human imaging. In comparison to mouse xenografts, rat models offer the advantages of clinical imaging capabilities, development of xenograft and metastatic models, in orthotopic sites. Human breast cancer cell lines MDA-MB-231 and MCF-7 show a variable take rate in mice, ∼ 68% incurring considerable cost and time. Having a more reproducible method is needed for breast cancer studies. Here we present evidence for development of a novel method in the immune-compromised nude rats. Spheroids grown under stem cell conditions were derived from human breast adenocarcinoma estrogen dependent (MCF-7, ZR-75-1) and independent (MDA-MB-231) lines, and xenografted in both subcutaneous and orthotopic (fat pad) sites in the nude rat. To verify that rat tumors could be studied in detail at spatial resolutions achievable on a clinical 3 Tesla scanner, high-resolution magnetic resonance imaging was performed to identify vascular, viable, and necrotic tumor regions. The breast cancer phenotype and was confirmed by immunohistochemistry for ER and HER2. Tumors were characterized with proliferation marker Ki67, vascularization by CD34 and VEGF, and presence of hypoxic regions by HIF1α. Our results indicated that spheroids from all three lines readily generated tumors independent of exogenous estrogen. MRI is an effective and sensitive method for investigating the biological behavior and vascularization of breast cancer. These findings offer a potential novel method for pre-clinical study and investigation of human breast cancer.
Citation Format: Reza Bayat Mokhtari, Joris Tchouala Nofiele, Syed S. Islam, Herman Yeger, Hai-Ling Margaret Cheng. Investigation of the biological properties of human breast cancer in a nude rat model. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1220. doi:10.1158/1538-7445.AM2014-1220
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Affiliation(s)
| | | | - Syed S. Islam
- University of Toronto Hospital for Sick Children, Toronto, Ontario, Canada
| | - Herman Yeger
- University of Toronto Hospital for Sick Children, Toronto, Ontario, Canada
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Alhamami M, Bayat Mokhtari R, Ganesh T, Tchouala Nofiele J, Yeger H, Margaret Cheng HL. Manganese-enhanced magnetic resonance imaging for early detection and characterization of breast cancers. Mol Imaging 2014; 13. [PMID: 25060340 DOI: 10.2310/7290.2014.00021] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Very early cancer detection is the key to improving cure. Our objective was to investigate manganese (Mn)-enhanced magnetic resonance imaging (MRI) for very early detection and characterization of breast cancers. Eighteen NOD scid gamma mice were inoculated with MCF7, MDA, and LM2 breast cancer cells and imaged periodically on a 3 T scanner beginning on day 6. T1-weighted imaging and T1 measurements were performed before and 24 hours after administering MnCl2. At the last imaging session, Gd-DTPA was administered and tumors were excised for histology (hematoxylin-eosin and CD34 staining). All mice, except for two inoculated with MCF7 cells, developed tumors. Tumors enhanced uniformly on Mn and showed clear borders. Early small tumors (≤ 5 mm3) demonstrated the greatest enhancement with a relative R1 (1/T1) change of 1.57 ± 0.13. R1 increases correlated with tumor size (r = -.34, p = .04). Differences in R1 increases among the three tumor subtypes were most evident in early tumors. Histology confirmed uniform cancer cell distribution within tumor masses and vasculature in the periphery, which was consistent with rim-like enhancement on Gd-DTPA. Mn-enhanced MRI is a promising approach for detecting very small breast cancers in vivo and may be valuable for very early cancer detection.
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Abstract
Objective Larger animal models provide relevant tumor burden in the development of advanced clinical imaging methods for non-invasive cancer detection and diagnosis, and are especially valuable for studying metastatic disease. Most available experimental models, however, are based on immune-compromised mice. To lay the foundation for studying spontaneous metastasis using non-invasive magnetic resonance imaging (MRI), this study aims to establish a highly metastatic breast cancer xenograft model in nude rats. Materials and Methods A highly metastatic variant of human adenocarcinoma MDA-MB-231 known as LM2 was inoculated into nude rats. Orthotopic and subcutaneous (flank) sites were compared, with half of the orthotopic injections guided by ultrasound imaging. MRI with gadolinium contrast administration was performed weekly beginning on Day 6 and ending on Day 104. Excised tumors were assessed on histology using hematoxylin and eosin and CD34. Fisher's exact test was used to compare successful tumor induction amongst different inoculation methods. Results Primary LM2 tumors were established orthotopically in all cases under ultrasound-guided injection, and none otherwise (p = 0.0028). Contrast-enhanced MRI revealed rapidly progressing tumors that reached critical size (15 mm diameter) in 2 to 3 weeks after inoculation. MRI and histology findings were consistent: LM2 tumors were characterized by low vascularity confined to the tumor rim and large necrotic cores with increasing interstitial fluid pressure. Conclusions The metastatic LM2 breast tumor model was successfully established in the mammary fat pads of nude rats, using ultrasound needle guidance as a non-invasive alternative to surgery. This platform lays the foundation for future development and application of MRI to study spontaneous metastasis and different stages throughout the metastatic cascade.
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Affiliation(s)
- Joris Tchouala Nofiele
- The Research Institute and Diagnostic Imaging, Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Hai-Ling Margaret Cheng
- The Research Institute and Diagnostic Imaging, Hospital for Sick Children, Toronto, Ontario, Canada
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
- Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
- The Institute of Biomaterials & Biomedical Engineering, University of Toronto, Toronto, Ontario, Canada
- * E-mail:
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Ganesh T, Mokhtari RB, Alhamami M, Yeger H, Cheng HLM. Manganese-enhanced MRI of minimally gadolinium-enhancing breast tumors. J Magn Reson Imaging 2014; 41:806-13. [PMID: 24591227 DOI: 10.1002/jmri.24608] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Accepted: 02/10/2014] [Indexed: 12/25/2022] Open
Abstract
PURPOSE To investigate the potential of manganese (Mn)-enhanced MRI for sensitive detection and delineation of tumors that demonstrate little enhancement on Gd-DTPA. MATERIALS AND METHODS Eighteen nude rats bearing 1 to 2 cm in diameter orthotopic breast tumors (ZR75 and LM2) were imaged on a 3 Tesla (T) clinical scanner. Gd-DTPA was administered intravenously and MnCl2 subcutaneously, both at 0.05 mmol/kg. T1 -weighted imaging and T1 measurements were performed precontrast, 10 min post-Gd-DTPA, and 24 h post-MnCl2 . Tumors were excised and histologically assessed using H&E (composition and necrosis) and CD34 (vascularity). RESULTS Most tumors (78%) demonstrated little enhancement (< 20% change in R1 ) on Gd-DTPA. MnCl2 administration achieved greater and more uniform enhancement throughout the tumor mass (i.e., not restricted to the tumor periphery), with R1 changing over 20% in 72% of tumors. MnCl2 -induced R1 changes compared with Gd-induced changes were significantly greater in both ZR75 (P < 0.01) and LM2 tumors (P < 0.05). Histology confirmed very low vascularity in both tumor models, and necrotic areas were well delineated only on Mn-enhanced MRI. CONCLUSION Mn-enhanced MRI is a promising approach for detection of low-Gd-enhancing tumors.
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Affiliation(s)
- Tameshwar Ganesh
- The Research Institute (Physiology & Experimental Medicine) and Diagnostic Imaging, Hospital for Sick Children, Toronto, Canada; Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Canada
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Nofiele JT, Haedicke IE, Zhu YLK, Zhang XA, Cheng HLM. Gadolinium-free extracellular MR contrast agent for tumor imaging. J Magn Reson Imaging 2014; 41:397-403. [PMID: 24399613 DOI: 10.1002/jmri.24561] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Accepted: 12/12/2013] [Indexed: 11/10/2022] Open
Abstract
PURPOSE To evaluate a new formulation of manganese porphyrin as a potential gadolinium (Gd)-free extracellular magnetic resonance imaging (MRI) contrast agent for dynamic contrast-enhanced (DCE) MRI of tumors. MATERIALS AND METHODS A previously reported new contrast agent, MnTCP, was evaluated in six female tumor-bearing nude rats. MRI was performed on a 3 T clinical scanner 3 to 4 weeks after inoculation of breast tumor cells in the mammary fat pads. Gd-DTPA was injected intravenously, followed by injection of MnTCP at least 2 hours later (both at 0.05 mmol/kg). T1 relaxation time measurements and DCE-MRI were performed. RESULTS Enhancement and clearance patterns were visually similar between MnTCP and Gd-DTPA. However, relative R1 increases in all 11 tumors were larger for MnTCP over 60 minutes postcontrast, the difference being significant as late as 20 minutes (R1post /R1pre = 1.42 ± 0.15 for MnTCP vs. 1.20 ± 0.08 for Gd-DTPA, P < 0.05). R1 -related effects for MnTCP were largely reduced after 60 minutes (R1post /R1pre = 1.13 ± 0.07) and completely gone within 24 hours (R1post /R1pre = 0.97 ± 0.06). DCE-MRI revealed a consistently larger (1.5 to over 2-fold) peak enhancement and higher values of the steepest slope, time-to-peak, and AUC60 in all tumors with MnTCP (P < 0.01). CONCLUSION MnTCP is an alternative to extracellular Gd agents for tumor imaging, offering sensitive detection and rapid renal clearance.
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Affiliation(s)
- Joris Tchouala Nofiele
- The Research Institute and Diagnostic Imaging, Hospital for Sick Children, Toronto, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Canada
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Cheng W, Haedicke IE, Nofiele J, Martinez F, Beera K, Scholl TJ, Cheng HLM, Zhang XA. Complementary strategies for developing Gd-free high-field T₁ MRI contrast agents based on Mn(III) porphyrins. J Med Chem 2014; 57:516-20. [PMID: 24328058 DOI: 10.1021/jm401124b] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Mn(III) porphyrin (MnP) holds the promise of addressing the emerging challenges associated with Gd-based clinical MRI contrast agents (CAs), namely, Gd-related adverse effect and decreasing sensitivity at high clinical magnetic fields. Two complementary strategies for developing new MnPs as Gd-free CAs with optimized biocompatibility were established to improve relaxivity or clearance rate. MnPs with distinct and tunable pharmacokinetic properties can consequently be constructed for different in vivo applications at clinical field of 3 T.
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Affiliation(s)
- Weiran Cheng
- Department of Chemistry, University of Toronto , Toronto, Ontario, M5S 3H6, Canada
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Cheng HLM, Haedicke IE, Cheng W, Tchouala Nofiele J, Zhang XA. Gadolinium-free T1 contrast agents for MRI: tunable pharmacokinetics of a new class of manganese porphyrins. J Magn Reson Imaging 2013; 40:1474-80. [PMID: 24214904 DOI: 10.1002/jmri.24483] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2013] [Accepted: 10/04/2013] [Indexed: 02/05/2023] Open
Abstract
PURPOSE To evaluate a new class of manganese porphyrins with tunable pharmacokinetics as potential gadolinium (Gd)-free T1 agents for contrast-enhanced magnetic resonance imaging (MRI). MATERIALS AND METHODS Two new contrast agents, MnTCP and MnP2, were evaluated in four female rats. MRI was performed daily up to 3 days postinjection (0.05 mmol/kg) on a 3 T clinical scanner. T1 relaxation times and dynamic contrast-enhanced MRI were performed to assess contrast enhancement and clearance in blood, heart, liver, kidney, and muscle. RESULTS Relative T1 decreases were similar for MnTCP and Gd-DTPA in all tissues but were significantly larger (P < 0.05) for MnP2 in blood, heart, kidney, and liver (2-6-fold larger). Clearance of MnTCP was similar to Gd-DTPA, with T1 returning to baseline by 40 minutes and complete elimination in 1 day. MnP2 was cleared from blood after 2 days and sustained a lowered T1 in other tissues for at least 1 hour (P < 0.05). The maximum enhancement, slope, and time-to-peak were similar between contrast agents. Only the parameter AUC60 differed, with MnP2 yielding the largest AUC60 values primarily through longer retention in tissue. CONCLUSION MnTCP and MnP2 offer distinct applications as Gd-free T1 contrast agents. MnTCP behaves like a Gd-DTPA analog, while MnP2 provides significantly greater and longer positive signal enhancement.
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Affiliation(s)
- Hai-Ling Margaret Cheng
- Physiology and Experimental Medicine and Diagnostic Imaging, Hospital for Sick Children, Toronto, Canada; Department of Medical Biophysics, University of Toronto, Toronto, Canada; Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada; Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Canada
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Abstract
Objective Manganese (Mn) is a positive magnetic resonance imaging (MRI) contrast agent that has been used to obtain physiological, biochemical, and molecular biological information. There is great interest to broaden its applications, but a major challenge is to increase detection sensitivity. Another challenge is distinguishing regions of Mn-related signal enhancement from background tissue with inherently similar contrast. To overcome these limitations, this study investigates the use of ultrashort echo time (UTE) and subtraction UTE (SubUTE) imaging for more sensitive and specific determination of Mn accumulation. Materials and Methods Simulations were performed to investigate the feasibility of UTE and SubUTE for Mn-enhanced MRI and to optimize imaging parameters. Phantoms containing aqueous Mn solutions were imaged on a MRI scanner to validate simulations predictions. Breast cancer cells that are very aggressive (MDA-MB-231 and a more aggressive variant LM2) and a less aggressive cell line (MCF7) were labeled with Mn and imaged on MRI. All imaging was performed on a 3 Tesla scanner and compared UTE and SubUTE against conventional T1-weighted spoiled gradient echo (SPGR) imaging. Results Simulations and phantom imaging demonstrated that UTE and SubUTE provided sustained and linearly increasing positive contrast over a wide range of Mn concentrations, whereas conventional SPGR displayed signal plateau and eventual decrease. Higher flip angles are optimal for imaging higher Mn concentrations. Breast cancer cell imaging demonstrated that UTE and SubUTE provided high sensitivity, with SubUTE providing background suppression for improved specificity and eliminating the need for a pre-contrast baseline image. The SubUTE sequence allowed the best distinction of aggressive breast cancer cells. Conclusions UTE and SubUTE allow more sensitive and specific positive-contrast detection of Mn enhancement. This imaging capability can potentially open many new doors for Mn-enhanced MRI in vascular, cellular, and molecular imaging.
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Affiliation(s)
- Joris Tchouala Nofiele
- Department of Medical Biophysics, University of Toronto, Toronto, Canada
- The Research Institute and Diagnostic Imaging, The Hospital for Sick Children, Toronto, Canada
| | - Hai-Ling Margaret Cheng
- Department of Medical Biophysics, University of Toronto, Toronto, Canada
- The Research Institute and Diagnostic Imaging, The Hospital for Sick Children, Toronto, Canada
- * E-mail:
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Clique H, Cheng HLM, Marie PY, Felblinger J, Beaumont M. 3D myocardial T
1
mapping at 3T using variable flip angle method: Pilot study. Magn Reson Med 2013; 71:823-9. [DOI: 10.1002/mrm.24688] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Hélène Clique
- Université de Lorraine; IADI; UMR S 947 Nancy France
- INSERM; IADI; U947 Nancy France
| | - Hai-Ling Margaret Cheng
- The Hospital for Sick Children; Research Institute; Toronto Ontario Canada
- University of Toronto; Medical Biophysics; Toronto Ontario Canada
| | - Pierre-Yves Marie
- Université de Lorraine; RCV; UMR S 961 Nancy France
- INSERM; RCV; U1116 Nancy France
- CHU Nancy; Department of Nuclear Medicine; Nancy France
| | - Jacques Felblinger
- Université de Lorraine; IADI; UMR S 947 Nancy France
- CHU Nancy; CIC-IT; Nancy France
- INSERM; CIC-IT, CIT801; Nancy France
| | - Marine Beaumont
- INSERM; IADI; U947 Nancy France
- CHU Nancy; CIC-IT; Nancy France
- INSERM; CIC-IT, CIT801; Nancy France
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Abstract
Conventional MR images are qualitative, and their signal intensity is dependent on several complementary contrast mechanisms that are manipulated by the MR hardware and software. In the absence of a quantitative metric for absolute interpretation of pixel signal intensities, one that is independent of scanner hardware and sequences, it is difficult to perform comparisons of MR images across subjects or longitudinally in the same subject. Quantitative relaxometry isolates the contributions of individual MR contrast mechanisms (T1, T2, T2) and provides maps, which are independent of the MR protocol and have a physical interpretation often expressed in absolute units. In addition to providing an unbiased metric for comparing MR scans, quantitative relaxometry uses the relationship between MR maps and physiology to provide a noninvasive surrogate for biopsy and histology. This study provides an overview of some promising clinical applications of quantitative relaxometry, followed by a description of the methods and challenges of acquiring accurate and precise quantitative MR maps. It concludes with three case studies of quantitative relaxometry applied to studying multiple sclerosis, liver iron, and acute myocardial infarction.
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Affiliation(s)
- Hai-Ling Margaret Cheng
- Physiology and Experimental Medicine, Research Institute, The Hospital for Sick Children, Toronto, ON, Canada
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Abstract
OBJECTIVE Inhalation of air with altered levels of oxygen and carbon dioxide to manipulate tissue oxygenation and perfusion has both therapeutic and diagnostic value. These physiological responses can be measured non-invasively with magnetic resonance (MR) relaxation times. However, interpreting MR measurements is not straight-forward in extra-cranial organs where gas challenge studies have only begun to emerge. Inconsistent results have been reported on MR, likely because different organs respond differently. The objective of this study was to elucidate organ-specific physiological responses to gas challenge underlying MR measurements by investigating oxygenation and perfusion changes in the normal liver and kidney cortex. MATERIALS AND METHODS Gas challenges (100% O(2), 10% CO(2), and carbogen [90% O(2)+10% CO(2)]) interleaved with room air was delivered to rabbits to investigate their effect on tissue oxygenation and perfusion. Real-time fiber-optic measurements of absolute oxygen and relative blood flow were made in the liver and kidney cortex. RESULTS Only the liver demonstrated a vasodilatory response to CO(2). Perfusion changes to other gases were minimal in both organs. Tissue oxygenation measurements showed the liver responding only when CO(2) was present and the kidney only when O(2) was present. CONCLUSION This study reveals distinct physiological response mechanisms to gas challenge in the liver and kidney. The detailed characterization of organ-specific responses is critical to improving our understanding and interpretation of MR measurements in various body organs, and will help broaden the application of MR for non-invasive studies of gas challenges.
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Affiliation(s)
- Hai-Ling Margaret Cheng
- Physiology & Experimental Medicine, The Hospital for Sick Children Research Institute, Toronto, Ontario, Canada.
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Loai Y, Sakib N, Janik R, Foltz WD, Cheng HLM. Human aortic endothelial cell labeling with positive contrast gadolinium oxide nanoparticles for cellular magnetic resonance imaging at 7 Tesla. Mol Imaging 2012; 11:166-175. [PMID: 22469244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023] Open
Abstract
Positive T₁ contrast using gadolinium (Gd) contrast agents can potentially improve detection of labeled cells on magnetic resonance imaging (MRI). Recently, gadolinium oxide (Gd₂O₃) nanoparticles have shown promise as a sensitive T₁ agent for cell labeling at clinical field strengths compared to conventional Gd chelates. The objective of this study was to investigate Gado CELLTrack, a commercially available Gd₂O₃ nanoparticle, for cell labeling and MRI at 7 T. Relaxivity measurements yielded r1 = 4.7 s⁻¹ mM⁻¹ and r₂/r₁ = 6.2. Human aortic endothelial cells were labeled with Gd₂O₃ at various concentrations and underwent MRI from 1 to 7 days postlabeling. The magnetic resonance relaxation times T₁ and T₂ of labeled cell pellets were measured. Cellular contrast agent uptake was quantified by inductively coupled plasma-atomic emission spectroscopy, which showed very high uptake compared to conventional Gd compounds. MRI demonstrated significant positive T₁ contrast and stable labeling on cells. Enhancement was optimal at low Gd concentrations, attained in the 0.02 to 0.1 mM incubation concentration range (corresponding cell uptake was 7.26 to 34.1 pg Gd/cell). Cell viability and proliferation were unaffected at the concentrations tested and up to at least 3 days postlabeling. Gd₂O₃ is a promising sensitive and stable positive contrast agent for cellular MRI at 7 T.
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Affiliation(s)
- Yasir Loai
- Department of Physiology and Experimental Medicine, The Research Institute, The Hospital for Sick Children, Toronto, ON, Canada
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Cheng HLM, Holowka S, Moineddin R, Odame I. Liver iron overload assessment by T *2 magnetic resonance imaging in pediatric patients: an accuracy and reproducibility study. Am J Hematol 2012; 87:435-7. [PMID: 22286974 DOI: 10.1002/ajh.23114] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Revised: 12/21/2011] [Accepted: 12/27/2011] [Indexed: 11/05/2022]
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Cheng HLM, Loai Y, Farhat WA. Monitoring tissue development in acellular matrix-based regeneration for bladder tissue engineering: multiexponential diffusion and T2* for improved specificity. NMR Biomed 2012; 25:418-426. [PMID: 22351641 DOI: 10.1002/nbm.1617] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 06/26/2010] [Accepted: 08/10/2010] [Indexed: 05/31/2023]
Abstract
Cell-seeded acellular matrices (ACMs) are a promising approach for the tissue engineering of soft tissues and organs, such as the urinary bladder. ACM contains site-preferred structural and functional molecules, and degradation products derived from ACM play important roles in tissue remodeling. Regeneration proceeds along concurrent trajectories of cell growth and matrix degradation, characterized by evolving biophysical and biochemical properties. The assessment of tissue development through a noninvasive imaging technique, such as MRI, must therefore be capable of distinguishing these concurrent biophysical and biochemical changes. However, although MRI provides exquisite sensitivity to tissue microstructure, composition and function, specificity remains limited. In this study, multiexponential diffusion and the effective transverse relaxation time T(2)* were investigated for their ability to assess cell growth and tissue composition, respectively. Bladder ACMs prepared with and without hyaluronic acid, and ACMs seeded with smooth muscle cells, were assessed on MRI. The slow diffusion fraction from multiexponential diffusion analysis demonstrated the best correlation with cellularity, with minimal influence from underlying matrix degradation. T(2)* measurements were sensitive to macromolecular content, specifically the presence of hyaluronic acid, without confounding influence from tissue hydration. T(2)* also appeared to be sensitive to cell filling of the matrix pore space. Compared with these metrics, commonly used MRI parameters, such as T(1), T(2) and single diffusion coefficients, were more limited in specificity. The use of T(2) to measure tissue structure and composition is limited by its large dependence on water content, and single diffusion can only reflect the overall characteristics of the extra- and intracellular environment. These findings are important for further development of more specific MRI methods for the monitoring of regeneration in tissue-engineered systems.
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Winter JD, Estrada M, Cheng HLM. Normal tissue quantitative T1 and T2* MRI relaxation time responses to hypercapnic and hyperoxic gases. Acad Radiol 2011; 18:1159-67. [PMID: 21704536 DOI: 10.1016/j.acra.2011.04.016] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2010] [Revised: 04/19/2011] [Accepted: 04/29/2011] [Indexed: 11/25/2022]
Abstract
RATIONALE AND OBJECTIVES Longitudinal (T(1)) and effective transverse (T(2)*) magnetic resonance (MR) relaxation times provide noninvasive measures of tissue oxygenation. The objective for this study was to quantify independent effects of inhaled O(2) and CO(2) on normal tissue T(1) and T(2)* in rabbit liver, kidney, and paraspinal muscle. MATERIALS AND METHODS Three gas challenges (100% O(2), 10% CO(2) [balance air], and carbogen [90% O(2) + 10% CO(2)]) were delivered to the rabbits in random order to isolate the effects of inspired O(2) and CO(2). During each challenge, quantitative T(1) and T(2)* maps were collected on a 1.5 Tesla MR imaging. Mean changes in T(1) (ΔT(1)) and T(2)* (ΔT(2)*) were calculated from regions of interest in each organ. RESULTS Greatest ΔT(1) and ΔT(2)* changes were observed in liver for 10% CO(2) and in kidney for 100% O(2). ΔT(1) and ΔT(2)* generally followed predicted patterns when transitioning from air breathing: lower T(1)/higher T(2)* with inspired O(2), higher T(1)/lower T(2)* with inspired CO(2), and variable T(1)/T(2)* changes in the presence of both (ie, carbogen). New observations also emerged: 1) between-gas-challenge transitions revealed the greatest significance in ΔT(2)* for the liver and kidney resulting from the isolation of independent O(2) and CO(2) effects; 2) ΔT(2)* provided the best sensitivity and detected both tissue oxygenation and blood volume modulation; and 3) ΔT(1) sensitivity was restricted mainly to tissue oxygenation in the absence of counteracting vasodilatation. CONCLUSION Robust use of MR relaxation times as noninvasive biomarkers requires an understanding of their relative sensitivity to organ-specific physiological responses.
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Winter JD, St Lawrence KS, Cheng HLM. Quantification of renal perfusion: comparison of arterial spin labeling and dynamic contrast-enhanced MRI. J Magn Reson Imaging 2011; 34:608-15. [PMID: 21761490 DOI: 10.1002/jmri.22660] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Accepted: 04/29/2011] [Indexed: 01/27/2023] Open
Abstract
PURPOSE To provide the first comparison of absolute renal perfusion obtained by arterial spin labeling (ASL) and separable compartment modeling of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI). Moreover, we provide the first application of the dual bolus approach to quantitative DCE-MRI perfusion measurements in the kidney. MATERIALS AND METHODS Consecutive ASL and DCE-MRI acquisitions were performed on six rabbits on a 1.5 T MRI system. Gadolinium (Gd)-DTPA was administered in two separate injections to decouple measurement of the arterial input function and tissue uptake curves. For DCE perfusion, pixel-wise and mean cortex region-of-interest tissue curves were fit to a separable compartment model. RESULTS Absolute renal cortex perfusion estimates obtained by DCE and ASL were in close agreement: 3.28 ± 0.59 mL/g/min (ASL), 2.98 ± 0.60 mL/g/min (DCE), and 3.57 ± 0.96 mL/g/min (pixel-wise DCE). Renal medulla perfusion was 1.53 ± 0.35 mL/g/min (ASL) but was not adequately described by the separable compartment model. CONCLUSION ASL and DCE-MRI provided similar measures of absolute perfusion in the renal cortex, offering both noncontrast and contrast-based alternatives to improve current renal MRI assessment of kidney function.
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Affiliation(s)
- Jeff D Winter
- Research Institute, Diagnostic Imaging, Hospital for Sick Children, Toronto, Canada
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Abstract
Magnetic resonance imaging (MRI) relaxation times provide indirect estimates of tissue O(2) for monitoring tumour oxygenation. This study provides insight into mechanisms underlying longitudinal (R(1) = 1/T(1)) and transverse effective (R(2)* = 1/T(2)*) relaxation rate changes during inhalation of 100% O(2) and 3%, 6% and 9% CO(2) (balanced O(2)) in a rabbit tumour model. Quantitative R(1), R(2)*, and dynamic contrast-enhanced (DCE) imaging was performed in six rabbits 12-23 days following implantation of VX2 carcinoma cells in the quadricep muscle. Invasive measurements of tissue partial pressure of O(2) (pO(2)) and perfusion were also performed, which revealed elevated pO(2) levels in all tumour regions for all hyperoxic gases compared to baseline (air) and reduced perfusion for carbogen. During 100% O(2) breathing, an R(1) increase and R(2)* decrease consistent with elevated pO(2) were observed within tumours. DCE-derived blood flow was weakly correlated with R(1) changes from air to 100% O(2). Further addition of CO(2) (carbogen) did not introduce considerable changes in MR relaxation rates, but a trend towards higher R(1) relative to breathing 100% O(2) was observed, while R(2)* changes were inconsistent. This observation supports the predominance of dissolved O(2) on R(1) sensitivity and demonstrates the value of R(1) over R(2)* for tissue oxygenation measures.
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Affiliation(s)
- Jeff D Winter
- The Research Institute and Diagnostic Imaging, The Hospital for Sick Children, Toronto, Canada
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Cheng HLM, Loai Y, Beaumont M, Farhat WA. The acellular matrix (ACM) for bladder tissue engineering: A quantitative magnetic resonance imaging study. Magn Reson Med 2011; 64:341-8. [PMID: 20665777 DOI: 10.1002/mrm.22404] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Bladder acellular matrices (ACMs) derived from natural tissue are gaining increasing attention for their role in tissue engineering and regeneration. Unlike conventional scaffolds based on biodegradable polymers or gels, ACMs possess native biomechanical and many acquired biologic properties. Efforts to optimize ACM-based scaffolds are ongoing and would be greatly assisted by a noninvasive means to characterize scaffold properties and monitor interaction with cells. MRI is well suited to this role, but research with MRI for scaffold characterization has been limited. This study presents initial results from quantitative MRI measurements for bladder ACM characterization and investigates the effects of incorporating hyaluronic acid, a natural biomaterial useful in tissue-engineering and regeneration. Measured MR relaxation times (T(1), T(2)) and diffusion coefficient were consistent with increased water uptake and glycosaminoglycan content observed on biochemistry in hyaluronic acid ACMs. Multicomponent MRI provided greater specificity, with diffusion data showing an acellular environment and T(2) components distinguishing the separate effects of increased glycosaminoglycans and hydration. These results suggest that quantitative MRI may provide useful information on matrix composition and structure, which is valuable in guiding further development using bladder ACMs for organ regeneration and in strategies involving the use of hyaluronic acid.
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Abstract
A rapid technique for mapping of T(2) relaxation times is presented. The method is based on the conventional single-echo spin echo approach but uses a much shorter pulse repetition time to accelerate data acquisition. The premise of the new method is the use of a constant difference between the echo time and pulse repetition time, which removes the conventional and restrictive requirement of pulse repetition time >> T(1). Theoretical and simulation investigations were performed to evaluate the criteria for accurate T(2) measurements. Measured T(2)s were shown to be within 1% error as long as the key criterion of pulse repetition time/T(2) > or =3 is met. Strictly, a second condition of echo time/T(1) << 1 is also required. However, violations of this condition were found to have minimal impact in most clinical scenarios. Validation was conducted in phantoms and in vivo T(2) mapping of healthy cartilage and brain. The proposed method offers all the advantages of single-echo spin echo imaging (e.g., immunity to stimulated echo effects, robustness to static field inhomogeneity, flexibility in the number and choice of echo times) in a considerably reduced amount of time and is readily implemented on any clinical scanner.
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Kershaw LE, Cheng HLM. A general dual-bolus approach for quantitative DCE-MRI. Magn Reson Imaging 2010; 29:160-6. [PMID: 21129878 DOI: 10.1016/j.mri.2010.08.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2010] [Revised: 08/09/2010] [Accepted: 08/27/2010] [Indexed: 12/27/2022]
Abstract
PURPOSE To present a dual-bolus technique for quantitative dynamic contrast-enhanced MRI (DCE-MRI) and show that it can give an arterial input function (AIF) measurement equivalent to that from a single-bolus protocol. METHODS Five rabbits were imaged using a dual-bolus technique applicable for high-resolution DCE-MRI, incorporating a time resolved imaging of contrast kinetics (TRICKS) sequence for rapid temporal sampling. AIFs were measured from both the low-dose prebolus and the high-dose main bolus in the abdominal aorta. In one animal, TRICKS and fast spoiled gradient echo (FSPGR) acquisitions were compared. RESULTS The scaled prebolus AIF was shown to match the main bolus AIF, with 95% confidence intervals overlapping for fits of gamma-variate functions to the first pass and linear fits to the washout phase, with the exception of one case. The AIFs measured using TRICKS and FSPGR were shown to be equivalent in one animal. CONCLUSION The proposed technique can capture even the rapid circulation kinetics in the rabbit aorta, and the scaled prebolus AIF is equivalent to the AIF from a high-dose injection. This allows separate measurements of the AIF and tissue uptake curves, meaning that each curve can then be acquired using a protocol tailored to its specific requirements.
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Affiliation(s)
- Lucy E Kershaw
- The Research Institute and Diagnostic Imaging, The Hospital for Sick Children, Toronto, Ontario, Canada
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Kershaw LE, Cheng HLM. Temporal resolution and SNR requirements for accurate DCE-MRI data analysis using the AATH model. Magn Reson Med 2010; 64:1772-80. [PMID: 20715059 DOI: 10.1002/mrm.22573] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2009] [Revised: 04/11/2010] [Accepted: 06/15/2010] [Indexed: 12/24/2022]
Abstract
Dynamic contrast-enhanced MRI has been used in conjunction with tracer kinetics modeling in a wide range of tissues for treatment monitoring, oncology drug development, and investigation of disease processes. Accurate measurement of model parameters relies on acquiring data with high temporal resolution and low noise, particularly for models with large numbers of free parameters, such as the adiabatic approximation to the tissue homogeneity model for separate measurements of blood flow and vessel permeability. In this simulation study, accuracy of the adiabatic approximation to the tissue homogeneity model was investigated, examining the effects of temporal resolution, noise levels, and error in the measured arterial input function. A temporal resolution of 1.5 s and high SNR (noise sd = 0.05) were found to ensure minimal bias (<5%) in all four model parameters (extraction fraction, blood flow, mean transit time, and extravascular extracellular volume), and the sampling interval can be relaxed to 6 s, if the transit time need not be measured accurately (bias becomes >10%). A 10% error in the measured height of the arterial input function first pass peak resulted in an error of at most 10% in each model parameter.
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Affiliation(s)
- Lucy E Kershaw
- The Research Institute and Diagnostic Imaging, The Hospital for Sick Children, Toronto, Canada
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Cheng HLM, Islam SS, Loai Y, Antoon R, Beaumont M, Farhat WA. Quantitative Magnetic Resonance Imaging Assessment of Matrix Development in Cell-Seeded Natural Urinary Bladder Smooth Muscle Tissue-Engineered Constructs. Tissue Eng Part C Methods 2010; 16:643-51. [DOI: 10.1089/ten.tec.2009.0099] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Hai-Ling Margaret Cheng
- Department of Medical Biophysics, University of Toronto, Toronto, Canada
- Physiology & Experimental Medicine, Research Institute, Toronto, Canada
- Diagnostic Imaging, The Hospital for Sick Children, Toronto, Canada
| | - Syed S. Islam
- Division of Urology, The Hospital for Sick Children, Toronto, Canada
| | - Yasir Loai
- Division of Urology, The Hospital for Sick Children, Toronto, Canada
| | - Roula Antoon
- Division of Urology, The Hospital for Sick Children, Toronto, Canada
| | - Marine Beaumont
- Physiology & Experimental Medicine, Research Institute, Toronto, Canada
- Diagnostic Imaging, The Hospital for Sick Children, Toronto, Canada
| | - Walid A. Farhat
- Division of Urology, The Hospital for Sick Children, Toronto, Canada
- Developmental and Stem Cell Biology, Research Institute, The Hospital for Sick Children, Toronto, Canada
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Studler U, White LM, Andreisek G, Luu S, Cheng HLM, Sussman MS. Impact of motion on T1 mapping acquired with inversion recovery fast spin echo and rapid spoiled gradient recalled-echo pulse sequences for delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) in volunteers. J Magn Reson Imaging 2010; 32:394-8. [DOI: 10.1002/jmri.22249] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Beaumont M, DuVal MG, Loai Y, Farhat WA, Sándor GK, Cheng HLM. Monitoring angiogenesis in soft-tissue engineered constructs for calvarium bone regeneration: an in vivo longitudinal DCE-MRI study. NMR Biomed 2010; 23:48-55. [PMID: 19650039 DOI: 10.1002/nbm.1425] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Tissue engineering is a promising technique for bone repair and can overcome the major drawbacks of conventional autogenous bone grafting. In this in vivo longitudinal study, we proposed a new tissue-engineering paradigm: inserting a biological soft-tissue construct within the bone defect to enhance angiogenesis for improved bone regeneration. The construct acts as a resorbable scaffold to support desired angiogenesis and cellular activity and as a vector of vascular endothelial growth factor, known to promote both vessel and bone growth. Dynamic contrast- enhanced magnetic resonance imaging was performed to investigate and characterize angiogenesis necessary for bone formation following the proposed paradigm of inserting a VEGF-impregnated tissue-engineered construct within the critical-sized calvarial defect in the membranous parietal bone of the rabbit. Results show that a model-free quantitative approach, the normalized initial area under the curve metric, provides sensitive and reproducible measures of vascularity that is consistent with known temporal evolution of angiogenesis during bone regeneration.
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Affiliation(s)
- Marine Beaumont
- The Research Institute, The Hospital for Sick Children, Toronto, Canada
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Cheng HLM. Improved correlation to quantitative DCE-MRI pharmacokinetic parameters using a modified initial area under the uptake curve (mIAUC) approach. J Magn Reson Imaging 2009; 30:864-72. [DOI: 10.1002/jmri.21916] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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