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Peperhove M, Vo Chieu VD, Jang MS, Gutberlet M, Hartung D, Tewes S, Warnecke G, Fegbeutel C, Haverich A, Gwinner W, Lehner F, Bräsen JH, Haller H, Wacker F, Gueler F, Hueper K. Assessment of acute kidney injury with T1 mapping MRI following solid organ transplantation. Eur Radiol 2017; 28:44-50. [PMID: 28710580 DOI: 10.1007/s00330-017-4943-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Revised: 04/08/2017] [Accepted: 06/09/2017] [Indexed: 12/29/2022]
Abstract
OBJECTIVES To evaluate T1 mapping as a non-invasive, functional MRI biomarker in patients shortly after solid organ transplantation to detect acute postsurgical kidney damage and to correlate T1 times with renal function. METHODS 101 patients within 2 weeks after solid organ transplantation (49 kidney transplantation, 52 lung transplantation) and 14 healthy volunteers were examined by MRI between July 2012 and April 2015 using the modified Look-Locker inversion recovery (MOLLI) sequence. T1 times in renal cortex and medulla and the corticomedullary difference were compared between groups using one-way ANOVA adjusted for multiple comparison with the Tukey test, and T1 times were correlated with renal function using Pearson's correlation. RESULTS Compared to healthy volunteers T1 times were significantly increased after solid organ transplantation in the renal cortex (healthy volunteers 987 ± 102 ms; kidney transplantation 1299 ± 101 ms, p < 0.001; lung transplantation 1058 ± 96 ms, p < 0.05) and to a lesser extent in the renal medulla. Accordingly, the corticomedullary difference was diminished shortly after solid organ transplantation. T1 changes were more pronounced following kidney compared to lung transplantation, were associated with the stage of renal impairment and significantly correlated with renal function. CONCLUSIONS T1 mapping may be helpful for early non-invasive assessment of acute kidney injury and renal pathology following major surgery such as solid organ transplantation. KEY POINTS • Renal cortical T1 relaxation times are prolonged after solid organ transplantation. • Cortical T1 values increase with higher stages of renal function impairment. • Corticomedullary difference decreases with higher stages of renal function impairment. • Renal cortical T1 relaxation time and corticomedullary difference correlate with renal function. • T1 mapping may be helpful for non-invasive assessment of post-operative renal pathology.
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Affiliation(s)
- Matti Peperhove
- Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Van Dai Vo Chieu
- Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Mi-Sun Jang
- Nephrology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Marcel Gutberlet
- Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Dagmar Hartung
- Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Susanne Tewes
- Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Gregor Warnecke
- Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Christiane Fegbeutel
- Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Axel Haverich
- Cardiothoracic, Transplantation and Vascular Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Wilfried Gwinner
- Nephrology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Frank Lehner
- General, Abdominal and Transplant Surgery, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Jan Hinrich Bräsen
- Pathology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Hermann Haller
- Nephrology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Frank Wacker
- Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Faikah Gueler
- Nephrology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Katja Hueper
- Diagnostic and Interventional Radiology, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
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52
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Longo DL, Cutrin JC, Michelotti F, Irrera P, Aime S. Noninvasive evaluation of renal pH homeostasis after ischemia reperfusion injury by CEST-MRI. NMR IN BIOMEDICINE 2017; 30:e3720. [PMID: 28370530 DOI: 10.1002/nbm.3720] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 02/06/2017] [Accepted: 02/06/2017] [Indexed: 06/07/2023]
Abstract
Acute kidney injury (AKI) in mice caused by sustained ischemia followed by reperfusion is associated with acute tubular necrosis and renal dysfunctional blood flow. Although the principal role of the kidney is the maintenance of acid-base balance, current imaging approaches are unable to assess this important parameter, and clinical biomarkers are not robust enough in evaluating the severity of kidney damage. Therefore, novel noninvasive imaging approaches are needed to assess the acid-base homeostasis in vivo. This study investigates the usefulness of MRI-chemical exchange saturation transfer (CEST) pH imaging (through iopamidol injection) in characterizing moderate and severe AKI in mice following unilateral ischemia reperfusion injury. Moderate (20 min) and severe (40 min) ischemia were induced in Balb/C mice, which were imaged at several time points thereafter (Days 0, 1, 2, 7). A significant increase of renal pH values was observed as early as one day after the ischemia reperfusion damage for both moderate and severe ischemia. MRI-CEST pH imaging distinguished the evolution of moderate from severe AKI. A recovery of normal renal pH values was observed for moderate AKI, whereas a persisting renal pH increase was observed for severe AKI on Day 7. Renal filtration fraction was significantly lower for clamped kidneys (0.54-0.57) in comparison to contralateral kidneys (0.84-0.86) following impairment of glomerular filtration. The severe AKI group showed a reduced filtration fraction even after 7 days (0.38 for the clamped kidneys). Notably, renal pH values were significantly correlated with the histopathological score. In conclusion, MRI-CEST pH mapping is a valid tool for the noninvasive evaluation of both acid-base balance and renal filtration in patients with ischemia reperfusion injury.
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Affiliation(s)
- Dario Livio Longo
- Istituto di Biostrutture e Bioimmagini (CNR), c/o Centro di Biotecnologie Molecolari, Torino, Italy
- Dipartimento di Biotecnologie Molecolari e Scienze per la Salute, Università degli Studi di Torino, Torino, Italy
| | - Juan Carlos Cutrin
- Dipartimento di Biotecnologie Molecolari e Scienze per la Salute, Università degli Studi di Torino, Torino, Italy
| | - Filippo Michelotti
- Dipartimento di Biotecnologie Molecolari e Scienze per la Salute, Università degli Studi di Torino, Torino, Italy
| | - Pietro Irrera
- Dipartimento di Biotecnologie Molecolari e Scienze per la Salute, Università degli Studi di Torino, Torino, Italy
| | - Silvio Aime
- Dipartimento di Biotecnologie Molecolari e Scienze per la Salute, Università degli Studi di Torino, Torino, Italy
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53
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Pan L, Chen J, Xing W, Xing Z, Zhang J, Peng Y, Zhang Z. Magnetic resonance imaging evaluation of renal ischaemia-reperfusion injury in a rabbit model. Exp Physiol 2017; 102:1000-1006. [PMID: 28470945 DOI: 10.1113/ep086203] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 04/24/2017] [Indexed: 02/06/2023]
Abstract
NEW FINDINGS What is the central question of this study? Renal ischaemia-reperfusion injury occurs in various clinical settings. The clinical diagnosis of ischaemia-reperfusion injury is routinely based on biochemical and haematological tests, which cannot evaluate the function of a single kidney. New magnetic resonance imaging techniques to identify the pathophysiological changes in the renal outer medulla were evaluated. What is the main finding and its importance? This study demonstrated that susceptibility-weighted imaging is a feasible non-invasive tool for imaging and evaluating physipathological changes in the renal outer medulla after ischaemia-reperfusion injury. The aim was to evaluate the feasibility of susceptibility-weighted imaging (SWI) as a tool to identify the changes in the renal outer medulla (OM) in a rabbit model of renal ischaemia-reperfusion injury (IRI). New Zealand rabbits were used (control group n = 10; IRI group n = 40). The rabbits in the IRI group were subjected to left renal artery clamping for 60 min. T2-weighted (T2WI) and SWI examinations were performed at 1, 12, 24 or 48 h after reperfusion (each n = 10). After the examinations, the kidneys were submitted to histological evaluation. The contrast-to-noise ratio (CNR) for the left renal OM was measured using T2WI and SWI. The T2WI and SWI scores of the integrity of the renal OM were evaluated. There were significant differences between T2WI CNRs and SWI CNRs in the control group and the IRI 1, 12 and 48 h time points (all P < 0.05). No significant difference was found between T2WI and SWI CNRs at IRI 24 h (P > 0.05). The mean SWI scores of renal OM in the IRI 1 and 12 h subgroups were both significantly lower than that in the control group (all P < 0.05). The only significant difference in the mean T2WI scores of renal OM was observed between the control and IRI 1 h groups (P < 0.05). Susceptibility-weighted imaging has a significant advantage in evaluation of healthy renal OM over conventional magnetic resonance imaging, and it is a feasible non-invasive tool for imaging and evaluating changes in the renal OM after IRI.
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Affiliation(s)
- Liang Pan
- Department of Radiology, the Third Affiliated Hospital of Suzhou University, Changzhou, People's Republic of China
| | - Jie Chen
- Department of Radiology, the Third Affiliated Hospital of Suzhou University, Changzhou, People's Republic of China.,Department of Medical Imaging, Jinling Hospital, Nanjing University School of Medicine, Nanjing, People's Republic of China
| | - Wei Xing
- Department of Radiology, the Third Affiliated Hospital of Suzhou University, Changzhou, People's Republic of China
| | - Zhaoyu Xing
- Department of Urology, the Third Affiliated Hospital of Suzhou University, Changzhou, People's Republic of China
| | - Jinggang Zhang
- Department of Radiology, the Third Affiliated Hospital of Suzhou University, Changzhou, People's Republic of China
| | - Yan Peng
- Department of Pathology, the Third Affiliated Hospital of Suzhou University, Changzhou, People's Republic of China
| | - Zhuoli Zhang
- Department of Radiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
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Thorenz A, Völker N, Bräsen JH, Chen R, Jang MS, Rong S, Haller H, Kirsch T, Vieten G, Klemann C, Gueler F. IL-17A blockade or deficiency does not affect progressive renal fibrosis following renal ischaemia reperfusion injury in mice. J Pharm Pharmacol 2017; 69:1125-1135. [DOI: 10.1111/jphp.12747] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 04/18/2017] [Indexed: 12/31/2022]
Abstract
Abstract
Objectives
IL-17A contributes to acute kidney injury and fibrosis. Therefore, we asked whether IL-17A deficiency or treatment with a IL-17A blocking antibody impacts severe renal ischaemia reperfusion injury (IRI) and the progression to chronic kidney disease (CKD).
Methods
IL-17A-deficient and wild-type (WT) mice underwent transient unilateral renal pedicle clamping for 45 min to induce IRI and subsequent renal fibrosis. Furthermore, a neutralizing anti-IL-17A antibody (mAb) was injected into WT mice before induction of renal IRI intravenously. On days 1, 7 and 21, inflammation, fibrosis, leukocyte infiltration and pro-inflammatory and pro-fibrotic cytokine expression were assessed in kidneys using histology, qPCR and flow cytometry.
Key findings
IL-17A was significantly increased after renal IRI in WT kidneys. Levels of pro-inflammatory (MCP-1) cytokine and pro-fibrotic (collagen 1α1, fibronectin) transcripts were similar in the experimental groups studied. IL-17A deficiency had no effect on renal T-cell influx or the number, inflammatory phenotype, or spatial distribution of macrophages. Similarly, administration of an IL-17A blocking antibody did not attenuate inflammation.
Conclusions
Despite the effects of IL-17 in other inflammation models, neither genetic IL-17A deficiency nor treatment with an IL-17A blocking antibody attenuated IRI and progression to CKD. We conclude that in severe renal IRI IL-17A is not crucially involved in disease progression.
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Affiliation(s)
- Anja Thorenz
- Nephrology, Hannover Medical School, Hannover, Germany
| | - Nicole Völker
- Nephrology, Hannover Medical School, Hannover, Germany
| | | | - Rongjun Chen
- Nephrology, Hannover Medical School, Hannover, Germany
| | - Mi-Sun Jang
- Nephrology, Hannover Medical School, Hannover, Germany
| | - Song Rong
- Nephrology, Hannover Medical School, Hannover, Germany
- The Transplantation Center of the Affiliated Hospital, Zunyi Medical College, Zunyi, China
| | | | - Torsten Kirsch
- Nephrology, Hannover Medical School, Hannover, Germany
- Core Facility Quality Management and Health Technology Assessment in Transplantation, Hannover Medical School, Hannover, Germany
| | - Gertrud Vieten
- Center of Pediatric Surgery, Hannover Medical School, Hannover, Germany
| | - Christian Klemann
- Center of Pediatric Surgery, Hannover Medical School, Hannover, Germany
| | - Faikah Gueler
- Nephrology, Hannover Medical School, Hannover, Germany
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Severe bilateral ischemic-reperfusion renal injury: hyperacute and acute changes in apparent diffusion coefficient, T1, and T2 mapping with immunohistochemical correlations. Sci Rep 2017; 7:1725. [PMID: 28496138 PMCID: PMC5431885 DOI: 10.1038/s41598-017-01895-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 04/04/2017] [Indexed: 02/08/2023] Open
Abstract
The aim of this study was to investigate the hyperacute and acute changes in apparent diffusion coefficient (ADC), T1, and T2 mapping in rat kidneys after severe bilateral renal ischemic-reperfusion injury (IRI). After baseline MRI, 24 Spraque-Dawley rats with renal IRI were divided equally as group 1 (post-IRI MRI at 6 hours, days 1, 3, and 7) and groups 2, 3, and 4 (post-IRI MRI at 6 hours; 6 hours and day 1; 6 hours, days 1 and 3, respectively), while six other rats without IRI (group 5) were used as sham control. ADC, T1, and T2 values of the cortex and outer and inner stripes of outer medulla (OSOM and ISOM), and immunohistochemical studies assessing monocyte chemoattractant protein-1 (MCP-1), CD68+ cells, tubular cast formation, and collagen deposition in three zones at different time points were evaluated. Significantly reduced ADCs in OSOM and ISOM are noninvasive biomarkers denoting hyperacute damages after IRI. Linear regression analysis revealed a significant inverse correlation between 6-hour/baseline ADC ratios and MCP-1 staining (P < 0.001, r2 = 0.738). ADC, T1, and T2 values are useful for assessing variable IRI changes in different layers depending on underlying microstructural and histopathological changes at different time points.
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56
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Tewes S, Gueler F, Chen R, Gutberlet M, Jang MS, Meier M, Mengel M, Hartung D, Wacker F, Rong S, Hueper K. Functional MRI for characterization of renal perfusion impairment and edema formation due to acute kidney injury in different mouse strains. PLoS One 2017; 12:e0173248. [PMID: 28319118 PMCID: PMC5358739 DOI: 10.1371/journal.pone.0173248] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 02/17/2017] [Indexed: 12/18/2022] Open
Abstract
Purpose The purpose was to characterize acute kidney injury (AKI) in C57BL/6 (B6)- and 129/Sv (Sv)-mice by noninvasive measurement of renal perfusion and tissue edema using functional MRI. Methods Different severities of AKI were induced in B6- and Sv-mice by renal ischemia reperfusion injury (IRI). Unilateral clamping of the renal pedicle for 35 min (moderate AKI) or 45 min (severe AKI) was done. MRI (7-Tesla) was performed 1, 7 and 28 days after surgery using a flow alternating inversion recovery (FAIR) arterial spin labeling (ASL) sequence. Maps of perfusion and T1-relaxation time were calculated. Relative MRI-parameters of the IRI kidney compared to the contralateral not-clipped kidney were compared between AKI severities and between mouse strains using unpaired t-tests. In addition, fibrosis was assessed by Masson Trichrome and collagen IV staining. Results After moderate AKI relative perfusion impairment was significantly higher in B6- than in Sv-mice at d7 (55±7% vs. 82±8%, p<0.05) and d28 (76±7% vs. 102±3%, p<0.01). T1-values increased in the early phase after AKI in both mouse strains. T1-increase was more severe after prolonged ischemia times of 45 min compared to 35 min in both mouse strains, measured in the renal cortex and outer stripe of outer medulla. Kidney volume loss (compared to the contralateral kidney) occurred already after 7 days but proceeded markedly towards 4 weeks in severe AKI. Early renal perfusion impairment was predictive for later kidney volume loss. The progression to chronic kidney disease (CKD) in the severe AKI model was similar in both mouse strains as revealed by histology. Conclusion Quantification of renal perfusion and tissue edema by functional MRI allows characterization of strain differences upon AKI. Renal perfusion impairment was stronger in B6- compared to Sv-animals following moderate AKI. Prolonged ischemia times were associated with more severe perfusion impairment and edema formation in the early phase and progression to CKD within 4 weeks of observation.
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Affiliation(s)
- Susanne Tewes
- Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
- * E-mail:
| | - Faikah Gueler
- Nephrology, Hannover Medical School, Hannover, Germany
| | - Rongjun Chen
- Nephrology, Hannover Medical School, Hannover, Germany
| | - Marcel Gutberlet
- Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
| | - Mi-Sun Jang
- Nephrology, Hannover Medical School, Hannover, Germany
| | - Martin Meier
- Laboratory Animal Science, Hannover Medical School, Hannover, Germany
| | - Michael Mengel
- Department of Laboratory Medicine & Pathology, University of Alberta, Edmonton, Canada
| | - Dagmar Hartung
- Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
| | - Frank Wacker
- Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
| | - Song Rong
- Nephrology, Hannover Medical School, Hannover, Germany
- The Transplantation Center of the affiliated hospital, Zunyi Medical College, Zunyi, China
| | - Katja Hueper
- Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
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57
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Kidney Transplantation: Multiparametric Functional Magnetic Resonance Imaging for Assessment of Renal Allograft Pathophysiology in Mice. Invest Radiol 2016; 51:58-65. [PMID: 26371534 DOI: 10.1097/rli.0000000000000205] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES The aims of this experimental study were to investigate renal allograft pathophysiology by multiparametric functional magnetic resonance imaging (MRI) and to directly correlate MRI parameters with renal histopathology in mouse models of allogenic and isogenic kidney transplantation (ktx). MATERIALS AND METHODS Allograft rejection was induced by transplantation of C57BL/6 (B6) donor kidneys into BALB/c recipients (allogenic ktx). B6 mice that received B6 kidneys served as controls (isogenic ktx). Three weeks after ktx, MRI was performed using a 7-T small-animal scanner. Flow sensitive alternating inversion recovery echoplanar imaging arterial spin labeling, multiecho turbo spin echo, and diffusion-weighted imaging sequences were acquired. Maps of renal perfusion, T2 and T1 relaxation times, and apparent diffusion coefficients were calculated. Histological changes in the kidney were evaluated according to Banff criteria. Renal cell infiltrates and fibrosis were quantified by immunohistochemistry. Differences between groups were assessed using the Mann-Whitney U test, and the correlation of MRI parameters with renal histopathology was determined by Spearman correlation analysis. RESULTS After allogenic, but not isogenic, ktx, animals developed acute allograft rejection. Allogenic grafts were infiltrated by macrophages and T-lymphocytes and exhibited marked renal fibrosis. Magnetic resonance imaging revealed stronger impairment of renal perfusion (56 ± 7 vs 293 ± 44 mL/[min × 100 g]; P < 0.01) and more pronounced increases in T2 (60.1 ± 2.0 vs 45.7 ± 1.2 milliseconds, P < 0.01) and T1 relaxation times (1938 ± 53 vs 1350 ± 27 milliseconds, P < 0.01) in allogenic than in isogenic kidneys. Apparent diffusion coefficient was reduced to 1.39 ± 0.14 × 10(-3) mm2/s in kidneys with an acute rejection and was 1.83 ± 0.05 × 10(-3) mm2/s in isogenic kidneys without rejection (P < 0.05). Magnetic resonance imaging parameters significantly correlated with the amount of cellular infiltration and renal fibrosis observed histologically. CONCLUSIONS Functional MRI allows detection of acute renal allograft rejection after allogenic ktx in mice. Functional MRI parameters correlate with cell infiltrates and fibrosis. Thus, MRI may be used noninvasively and longitudinally to investigate mechanisms of renal allograft rejection and evaluate novel therapeutic strategies in experimental studies.
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58
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Hueper K, Gutberlet M, Bräsen JH, Jang MS, Thorenz A, Chen R, Hertel B, Barrmeyer A, Schmidbauer M, Meier M, von Vietinghoff S, Khalifa A, Hartung D, Haller H, Wacker F, Rong S, Gueler F. Multiparametric Functional MRI: Non-Invasive Imaging of Inflammation and Edema Formation after Kidney Transplantation in Mice. PLoS One 2016; 11:e0162705. [PMID: 27632553 PMCID: PMC5025122 DOI: 10.1371/journal.pone.0162705] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Accepted: 08/27/2016] [Indexed: 11/19/2022] Open
Abstract
Background Kidney transplantation (ktx) in mice is used to learn about rejection and to develop new treatment strategies. Past studies have mainly been based on histological or molecular biological methods. Imaging techniques to monitor allograft pathology have rarely been used. Methods Here we investigated mice after isogenic and allogenic ktx over time with functional MRI with diffusion-weighted imaging (DWI) and mapping of T2-relaxation time (T2-mapping) to assess graft inflammation and edema formation. To characterize graft pathology, we used PAS-staining, counted CD3-positive T-lymphocytes, analyzed leukocytes by means flow cytometry. Results DWI revealed progressive restriction of diffusion of water molecules in allogenic kidney grafts. This was paralleled by enhanced infiltration of the kidney by inflammatory cells. Changes in tissue diffusion were not seen following isogenic ktx. T2-times in renal cortex were increased after both isogenic and allogenic transplantation, consistent with tissue edema due to ischemic injury following prolonged cold ischemia time of 60 minutes. Lack of T2 increase in the inner stripe of the inner medulla in allogenic kidney grafts matched loss of tubular autofluorescence and may result from rejection-driven reductions in tubular water content due to tubular dysfunction and renal functional impairment. Conclusions Functional MRI is a valuable non-invasive technique for monitoring inflammation, tissue edema and tubular function. It permits on to differentiate between acute rejection and ischemic renal injury in a mouse model of ktx.
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Affiliation(s)
- Katja Hueper
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
- * E-mail:
| | - Marcel Gutberlet
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
| | | | - Mi-Sun Jang
- Department of Nephrology, Hannover Medical School, Hannover, Germany
| | - Anja Thorenz
- Department of Nephrology, Hannover Medical School, Hannover, Germany
| | - Rongjun Chen
- Department of Nephrology, Hannover Medical School, Hannover, Germany
- The kidney disease centre of the First Affiliated Hospital, Zhejiang University, Hangzhou, China
| | - Barbara Hertel
- Department of Nephrology, Hannover Medical School, Hannover, Germany
| | - Amelie Barrmeyer
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
| | - Martina Schmidbauer
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
| | - Martin Meier
- Institute for Laboratory Animal Science, Hannover Medical School, Hannover, Germany
| | | | | | - Dagmar Hartung
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
| | - Hermann Haller
- Department of Nephrology, Hannover Medical School, Hannover, Germany
| | - Frank Wacker
- Institute for Diagnostic and Interventional Radiology, Hannover Medical School, Hannover, Germany
| | - Song Rong
- Department of Nephrology, Hannover Medical School, Hannover, Germany
- The Transplantation Center of the affiliated hospital, Zunyi Medical College, Zunyi, China
| | - Faikah Gueler
- Department of Nephrology, Hannover Medical School, Hannover, Germany
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Friedli I, Crowe LA, Berchtold L, Moll S, Hadaya K, de Perrot T, Vesin C, Martin PY, de Seigneux S, Vallée JP. New Magnetic Resonance Imaging Index for Renal Fibrosis Assessment: A Comparison between Diffusion-Weighted Imaging and T1 Mapping with Histological Validation. Sci Rep 2016; 6:30088. [PMID: 27439482 PMCID: PMC4954968 DOI: 10.1038/srep30088] [Citation(s) in RCA: 87] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 06/29/2016] [Indexed: 12/12/2022] Open
Abstract
A need exists to noninvasively assess renal interstitial fibrosis, a common process
to all kidney diseases and predictive of renal prognosis. In this translational
study, Magnetic Resonance Imaging (MRI) T1 mapping and a new segmented
Diffusion-Weighted Imaging (DWI) technique, for Apparent Diffusion Coefficient
(ADC), were first compared to renal fibrosis in two well-controlled animal models to
assess detection limits. Validation against biopsy was then performed in 33 kidney
allograft recipients (KARs). Predictive MRI indices, ΔT1 and
ΔADC (defined as the cortico-medullary differences), were compared to
histology. In rats, both T1 and ADC correlated well with fibrosis and inflammation
showing a difference between normal and diseased kidneys. In KARs, MRI indices were
not sensitive to interstitial inflammation. By contrast, ΔADC
outperformed ΔT1 with a stronger negative correlation to fibrosis
(R2 = 0.64 against
R2 = 0.29
p < 0.001). ΔADC tends to negative values
in KARs harboring cortical fibrosis of more than 40%. Using a discriminant analysis
method, the ΔADC, as a marker to detect such level of fibrosis or
higher, led to a specificity and sensitivity of 100% and 71%, respectively. This new
index has potential for noninvasive assessment of fibrosis in the clinical
setting.
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Affiliation(s)
- I Friedli
- Division of Radiology, Department of Radiology and Medical Informatics Geneva University Hospitals and Faculty of Medicine of the University of Geneva, Switzerland
| | - L A Crowe
- Division of Radiology, Department of Radiology and Medical Informatics Geneva University Hospitals and Faculty of Medicine of the University of Geneva, Switzerland
| | - L Berchtold
- Service of Nephrology, Department of Internal Medicine Specialties, Geneva University Hospitals, University of Geneva, Faculty of Medicine, Geneva, Switzerland
| | - S Moll
- Division of Pathology, Geneva University Hospitals and Faculty of Medicine of the University of Geneva, Switzerland
| | - K Hadaya
- Divisions of Nephrology and Transplantation, Geneva University Hospitals and Faculty of Medicine of the University of Geneva, Switzerland
| | - T de Perrot
- Division of Radiology, Department of Radiology and Medical Informatics Geneva University Hospitals and Faculty of Medicine of the University of Geneva, Switzerland
| | - C Vesin
- Division of Cell Physiology and Metabolism, Geneva University Hospitals and Faculty of Medicine of the University of Geneva, Switzerland
| | - P-Y Martin
- Service of Nephrology, Department of Internal Medicine Specialties, Geneva University Hospitals, University of Geneva, Faculty of Medicine, Geneva, Switzerland
| | - S de Seigneux
- Service of Nephrology, Department of Internal Medicine Specialties, Geneva University Hospitals, University of Geneva, Faculty of Medicine, Geneva, Switzerland
| | - J-P Vallée
- Division of Radiology, Department of Radiology and Medical Informatics Geneva University Hospitals and Faculty of Medicine of the University of Geneva, Switzerland
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60
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Grenier N, Merville P, Combe C. Radiologic imaging of the renal parenchyma structure and function. Nat Rev Nephrol 2016; 12:348-59. [DOI: 10.1038/nrneph.2016.44] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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