TY - JOUR A1 - Adams, L. C. A1 - Brangsch, J. A1 - Reimann, C. A1 - Kaufmann, Jan Ole A1 - Buchholz, R. A1 - Karst, U. A1 - Botnar, R. M. A1 - Hamm, B. A1 - Makowski, M. R. T1 - Simultaneous molecular MRI of extracellular matrix collagen and inflammatory activity to predict abdominal aortic aneurysm rupture JF - Scientific Reports N2 - Abdominal aortic aneurysm (AAA) is a life-threatening vascular disease with an up to 80% mortality in case of rupture. Current biomarkers fail to account for size-independent risk of rupture. By combining the information of different molecular probes, multi-target molecular MRI holds the potential to enable individual characterization of AAA. In this experimental study, we aimed to examine the feasibility of simultaneous imaging of extracellular collagen and inflammation for size-independent prediction of risk of rupture in murine AAA. The study design consisted of: (1) A outcome-based longitudinal study with imaging performed once after one week with follow-up and death as the end-point for assessment of rupture risk. (2) A week-by-week study for the characterization of AAA development with imaging after 1, 2, 3 and 4 weeks. For both studies, the animals were administered a type 1 collagen-targeted gadolinium-based probe (surrogate marker for extracellular matrix (ECM) remodeling) and an iron oxide-based probe (surrogate marker for inflammatory activity), in one imaging session. In vivo measurements of collagen and iron oxide probes showed a significant correlation with ex vivo histology (p < 0.001) and also corresponded well to inductively-coupled plasma-mass spectrometry and laser-ablation inductively-coupled plasma mass spectrometry. Combined evaluation of collagen-related ECM remodeling and inflammatory activity was the most accurate predictor for AAA rupture (sensitivity 80%, specificity 100%, area under the curve 0.85), being superior to information from the individual probes alone. Our study supports the feasibility of a simultaneous assessment of collagen-related extracellular matrix remodeling and inflammatory activity in a murine model of AAA. KW - Atherosclerosis KW - Specific probe KW - Magnetic resonance imaging KW - Gadolinium KW - Iron oxide KW - Ferumoxytol KW - Inductively‑coupled mass spectrometry KW - ICP-MS KW - LA-ICP-MS KW - Laser ablation PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-525864 UR - https://www.nature.com/articles/s41598-020-71817-x DO - https://doi.org/10.1038/s41598-020-71817-x VL - 10 IS - 1 SP - 15206 PB - Springer Nature Limited CY - London, New York, Berlin, Shanghai and Tokyo AN - OPUS4-52586 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Adams, L. C. A1 - Brangsch, J. A1 - Reimann, C. A1 - Kaufmann, Jan Ole A1 - Nowak, K. A1 - Buchholz, R. A1 - Karst, U. A1 - Botnar, R. M. A1 - Hamm, B. A1 - Makowski, M. R. T1 - Noninvasive imaging of vascular permeability to predict the risk of rupture in abdominal aortic aneurysms using an albumin binding probe JF - Scientific Reports N2 - Abdominal aortic aneurysm (AAA) remains a fatal disease. Its development encompasses a complex interplay between hemodynamic stimuli on and changes in the arterial wall. Currently available biomarkers fail to predict the risk of AAA rupture independent of aneurysm size. Therefore, novel biomarkers for AAA characterization are needed. In this study, we used a mouse model of AAA to investigate the potential of magnetic resonance imaging (MRI) with an albumin-binding probe to assess changes in vascular permeability at different stages of aneurysm growth. Two imaging studies were performed: a longitudinal study with follow-up and death as endpoint to predict rupture risk and a week-by-week study to characterize AAA development. AAAs, which eventually ruptured, demonstrated a significantly higher in vivo MR signal enhancement from the albumin-binding probe (p = 0.047) and a smaller non-enhancing thrombus area compared to intact AAAs (p = 0.001). The ratio of albumin-binding-probe enhancement of the aneurysm wall to size of non-enhancing-thrombus-area predicted AAA rupture with high sensitivity/specificity (100%/86%). More advanced aneurysms with higher vascular permeability demonstrated an increased uptake of the albumin-binding-probe. These results indicate that MRI with an albumin-binding probe may enable noninvasive assessment of vascular permeability in murine AAAs and prediction of rupture risk. KW - Magnetic resonance imaging KW - Imaging KW - Tomography KW - Gadolinium KW - Contrast agent KW - Atherosclerosis KW - ICP-MS KW - Gadofosveset KW - Angiography KW - LA-ICP-MS PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-525541 DO - https://doi.org/10.1038/s41598-020-59842-2 VL - 10 SP - Article number: 3231 PB - Springer Nature Limited CY - London, New York, Berlin, Shanghai and Tokyo AN - OPUS4-52554 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Keller, S. A1 - Borde, T. A1 - Brangsch, J. A1 - Reimann, C. A1 - Kader, A. A1 - Schulze, D. A1 - Buchholz, R. A1 - Kaufmann, Jan Ole A1 - Karst, U. A1 - Schellenberger, E. A1 - Hamm, B. A1 - Makowski, M. R. T1 - Assessment of the hepatic tumor extracellular matrix using elastin‑specific molecular magnetic resonance imaging in an experimental rabbit cancer model JF - Scientific Reports N2 - To investigate the imaging performance of an elastin-specific molecular magnetic resonance imaging (MRI) probe with respect to the extracellular matrix (ECM) in an experimental hepatic cancer model. Twelve rabbits with hepatic VX2 tumors were examined using 3 T MRI 14, 21, and 28 days after tumor implantation for two subsequent days (gadobutrol, day 1; elastin-specific probe, day 2). The relative enhancement (RE) of segmented tumor regions (central and margin) and the peritumoral matrix was calculated using pre-contrast and delayed-phase T1w sequences. MRI measurements were correlated to histopathology and element-specific and spatially resolved mass spectrometry (MS). Mixed-model analysis was performed to assess the performance of the elastin-specific probe. In comparison to gadobutrol, the elastin probe showed significantly stronger RE, which was pronounced in the tumor margin (day 14–28: P ≤ 0.007). In addition, the elastin probe was superior in discriminating between tumor regions (χ2(4) = 65.87; P < 0.001). MRI-based measurements of the elastin probe significantly correlated with the ex vivo elastinstain (R = .84; P <0 .001) and absolute gadolinium concentrations (ICP-MS: R = .73, P <0 .01). LA-ICP-MS imaging confirmed the colocalization of the elastin-specific probe with elastic fibers. Elastin-specific molecular MRI is superior to non-specific gadolinium-based contrast agents in imaging the ECM of hepatic tumors and the peritumoral tissue. KW - Elastin-specific molecular agent KW - Extracellular matrix KW - Hepatocellular carcinoma KW - Inductively coupled plasma mass spectroscopy KW - Laser ablation-inductively coupled plasma-mass spectrometry KW - Magnetic resonance imaging KW - MR imaging KW - ESMA KW - Gadolinium PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-517360 DO - https://doi.org/10.1038/s41598-020-77624-8 VL - 10 IS - 1 SP - 20785 PB - Nature AN - OPUS4-51736 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -