Radiology Report: Contrast Agent Lab

Posted on March 2021

Professor Jamey Weichert, PhD started the Contrast Agent Lab when he came to UW in 1998. The lab designs, synthesizes, and evaluates novel targeted molecular imaging agents for CT, MR, and nuclear medicine, including PET. They take a biochemical approach to design, using naturally occurring compounds known to be stored or metabolized in the organ or tissue of interest, to serve as carriers for the radiologic moiety. Lab members work closely with the molecular imaging group, cancer geneticists, tumor biologists and clinicians at UW. Learn more about the Contrast Agent Lab and their current projects below.

Dr. Weichert was trained as a medicinal chemist and worked in a large nuclear pharmacy as an undergraduate before going to graduate school to work with Professor Raymond Counsell, who was well-known for developing radiopharmaceuticals. For his thesis, Dr. Weichert developed new iodinated contrast agents to use in CT scanning, which he continued researching long after graduation. The CT contrast agents he has since developed in his lab are being supplied by Medilumine (Montreal), for preclinical use in animal model micro-CT scanning. He also expanded on his initial research to study MRI and optical contrast agents.

While CT contrast agent research presents exciting opportunities for advancement in the imaging field, Dr. Weichert’s latest research has focused on radiopharmaceuticals for cancer imaging and therapy. He is currently working to combine tumor-targeted radionuclide therapy (TRT) with immunotherapy to cure tumors. “Our current research has afforded complete tumor response in a majority of tumor-bearing mice, and results in T-cell memory induction capable of preventing subsequent return of the same cancer,” explains Dr. Weichert.

This work, done collaboratively with several other UW labs, has garnered over $20 million in research funding over the past three years, including a $12.5 million dollar, five-year NCI PO1 grant from the National Institutes of Health in 2020.

Now that the team has overcome sensitivity challenges with developing a tumor-selective MR contrast agent, they are looking to push their research further to develop a dual-modality, tumor-selective MR/CT contrast agent. “By extending our current approach and using modeling calculations, this goal appears feasible. We are just synthesizing the first target compound now, and hope to continue advancing this research,” Dr. Weichert says.

A component critical to this lab’s success is their ability to work with the UW Small Animal Imaging and Radiotherapy Facility (SAIRF). The SAIRF is one of the top small animal imaging facilities in the country and offers advanced tools to assist in research. One of these technologies is the hybrid SPECT/CT scanner that was installed in late 2020, which is capable of 250-micron SPECT and 5-micron CT resolution, both of which are about 50 times better than is possible with clinical scanners.

One of the best things about the lab is that all of their work is designed for translation to the clinic. “The wonderful facilities and advanced research will hopefully establish UW as a leading destination for theranostic cancer treatment, capable of conducting paradigm-changing clinical trials and providing top patient care,” says Dr. Weichert.

Learn more about the Contrast Agent Lab and their current projects here: