Because gadolinium-based contrast agents have been shown to be retained in the brain, the industry has been on a quest to find a viable alternative.

A human protein-based tumor-targeting MR contrast agent that can be easily cleared by the body may be what they’ve been looking for.

A team led by Gang Han, associate professor at the University of Massachusetts Medical School, designed this new contrast agent and found that it holds promise for clinical application. He told HCB News that to the best of his knowledge, it’s the first human protein-based MR contrast.
Sugar has also been investigated as a potential alternative to gadolinium. Research published in Tomography in January and Radiology last month demonstrated that sugar can be used as an MR contrast agent to detect tumors.

Han’s team focused on proteins because they are naturally-occurring nanomaterials. The protein-bound nanoparticle Abraxane, for example, can be used to treat metastatic breast cancer, and protein scaffolds can improve the effectiveness of contrast agents.

In a paper published last month in Nano Letters, Han and his colleagues explained how they created a protein-based contrast agent. They used human transferrin (Tf) proteins to mimic the natural process of forming special nanoparticles called gadolinium biomineralized human Tf protein-based nanoparticles (Gd@TfNP).

The Gd@TfNPs preserve the functions of Tf very well, have superior chemical and physical properties and are brighter, compared to the gadolinium-based agents currently in use, said Han.

Because of that, Gd@TfNPs can be used as systemically clearable contrast agents for detecting early-stage tumors with MR. They can also be used to optimize drug dose and evaluate clinical results.

“This patent of this technology has been submitted,” said Han. “There is already some industry interest since this paper was published.”

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