Inflammatory bowel disease (IBD) which includes Crohn's disease and ulcerative colitis affects about 1.4 million patients in the United States, including many children and young adults. It is characterized by extensive inflammatory changes in the bowel wall with overexpression of molecular inflammation markers such as P- selectin on vascular endothelial cells in the bowel wall. Due to the chronicity of IBD with multipl relapses and long treatment phases including drugs such as immunosuppressants and -modulators that are associated with major side-effects, regular and accurate monitoring of the disease's activity is of paramount importance. Since multiple follow-up exams are needed, often over many years, monitoring should be noninvasive and, above all, patient-friendly. Currently, a simple technique that meets all these requirements is not available. Ultrasound (US) is a non-invasive imaging approach that already meets many of those requirements because 1) it is widely available at relatively low cost, and 2) it does not expose patients to ionizing irradiation (which is very important for repetitive examinations in particular in children and young adults). However, current US technology lacks the sensitivity and specificity to accurately quantify inflammation in the bowel wall. Furthermore, imaging the bowel with US can be technically challenging (e.g., spatial orientation within the large volume of the bowel, possible artifacts fro intraluminal gas, motion, etc). In this grant proposal we combine the advantages of US with those of molecular imaging and develop a molecular US imaging strategy using novel contrast microbubbles that allow inflammation imaging at the molecular level. We have designed a clinical grade microbubble that targets the inflammation marker P-selectin (P-MB) with the goal to transition molecular US for monitoring inflammation into clinical trials.
In specific aim 1, we will test molecular US using novel clinical grade P-MB for imaging and quantification of inflammation at the molecular level in a murine IBD model.
In specific aim 2, we will compare its potential for monitoring inflammation in IBD to 18FDG-PET-CT and DCE-MRI, using ex vivo assays as the gold standard.
In specific aim 3, we will translate our imaging approach from small to large animals in a porcine IBD model as a further step towards clinical translation. Critical data on the feasibility of an optimized molecular US imaging approach in porcine models of IBD (including terminal ileitis and colitis) will be obtained including the opportunity to correate in vivo imaging signals with ex vivo P- selectin expression levels and assessing optimal dosing of novel P-MB in pigs before eventual translation of our novel imaging approach into first-in-human clinical trials. We will also develop and test a novel real-time fused MRI/molecular US imaging approach of the bowel, addressing anticipated challenges when eventually translating molecular US imaging into the clinic, such as the need to image a large volume to obtain representative images of inflamed bowel segments, along with spatial orientation to reliably localize inflamed bowel segments within the large field of view of the bowel, as well as the need to reduce possible artifacts from intraluminal gas and motion. Following successful completion of our research aims, we anticipate rapid translation of this patient-friendly, non-invasive and quantitative imaging technique into the clinic to improve clinical management and outcome of patients with IBD.

Public Health Relevance

Current strategies for monitoring the disease's activity in patients with inflammatory bowel disease (IBD) have major limitations largely hampering personalized clinical management. In this research proposal, we will test the accuracy of a new targeted ultrasound imaging approach that allows non-invasive monitoring of inflammation in IBD at the molecular level without the use of radiation. The successful completion of our aims will lead to the development of a new imaging approach that can be used to more accurately monitor inflammation of the bowel in patients with IBD.

National Institute of Health (NIH)
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Research Project (R01)
Project #
Application #
Study Section
Medical Imaging Study Section (MEDI)
Program Officer
Hamilton, Frank A
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Stanford University
Schools of Medicine
United States
Zip Code
Li, You Leo; Hyun, Dongwoon; Abou-Elkacem, Lotfi et al. (2016) Visualization of Small-Diameter Vessels by Reduction of Incoherent Reverberation With Coherent Flow Power Doppler. IEEE Trans Ultrason Ferroelectr Freq Control 63:1878-1889
Zhou, Jianhua; Wang, Huaijun; Zhang, Huiping et al. (2016) VEGFR2-Targeted Three-Dimensional Ultrasound Imaging Can Predict Responses to Antiangiogenic Therapy in Preclinical Models of Colon Cancer. Cancer Res 76:4081-9
Abou-Elkacem, Lotfi; Wilson, Katheryne E; Johnson, Sadie M et al. (2016) Ultrasound Molecular Imaging of the Breast Cancer Neovasculature using Engineered Fibronectin Scaffold Ligands: A Novel Class of Targeted Contrast Ultrasound Agent. Theranostics 6:1740-52
Mullick Chowdhury, Sayan; Wang, Tzu-Yin; Bachawal, Sunitha et al. (2016) Ultrasound-guided therapeutic modulation of hepatocellular carcinoma using complementary microRNAs. J Control Release 238:272-80
Wang, Tzu-Yin; Choe, Jung Woo; Pu, Kanyi et al. (2015) Ultrasound-guided delivery of microRNA loaded nanoparticles into cancer. J Control Release 203:99-108
Machtaler, Steven; Knieling, Ferdinand; Luong, Richard et al. (2015) Assessment of Inflammation in an Acute on Chronic Model of Inflammatory Bowel Disease with Ultrasound Molecular Imaging. Theranostics 5:1175-86
Wang, Huaijun; Hristov, Dimitre; Qin, Jiale et al. (2015) Three-dimensional Dynamic Contrast-enhanced US Imaging for Early Antiangiogenic Treatment Assessment in a Mouse Colon Cancer Model. Radiology 277:424-34
Laeseke, Paul F; Chen, Ru; Jeffrey, R Brooke et al. (2015) Combining in Vitro Diagnostics with in Vivo Imaging for Earlier Detection of Pancreatic Ductal Adenocarcinoma: Challenges and Solutions. Radiology 277:644-61
Abou-Elkacem, Lotfi; Bachawal, Sunitha V; Willmann, Jürgen K (2015) Ultrasound molecular imaging: Moving toward clinical translation. Eur J Radiol 84:1685-93
Wang, Huaijun; Kaneko, Osamu F; Tian, Lu et al. (2015) Three-dimensional ultrasound molecular imaging of angiogenesis in colon cancer using a clinical matrix array ultrasound transducer. Invest Radiol 50:322-9

Showing the most recent 10 out of 16 publications