When cancer immunotherapy meets ultrasound, the result is non-invasive and no side effects to eliminate solid tumors!

Bioengineers at the University of California, San Diego have developed a cancer immunotherapy that pairs ultrasound with anti-cancer immune cells to destroy malignant tumors while preserving normal tissues
.

This new experimental therapy significantly slowed the growth of solid cancer tumors in mice
.

The team is led by Peter Yingxiao Wang, professor of bioengineering at the University of California, San Diego, and Shu Chien, professor emeritus of bioengineering, who detailed their work in a paper published in the journal Nature Biomedical Engineering on August 12
.

This work solved a long-standing problem in the field of cancer immunotherapy: how to make chimeric antigen receptor (CAR) T cell therapy to treat solid tumors safely and effectively
.

CAR-T cell therapy is a promising new method to treat cancer
.

It involves collecting the patient's T cells and genetically engineering them to express a special receptor called CAR on the surface, which can recognize specific antigens on cancer cells

This therapy is effective for some blood cancers and lymphomas, but it is not effective for solid tumors
.

This is because many target antigens on these tumors are also expressed on normal tissues and organs

First author Yiqian (Shirley) Wu said: "CAR-T cells are so powerful that they can also attack normal tissues and express low levels of target antigens
.

"

"The problem with standard CAR-T cells is that they are always there-they always express the CAR protein, so you can't control their activation," Wu explained
.

To solve this problem, the research team took standard CAR-T cells and reorganized them so that they only express CAR protein when using ultrasound energy
.

This allows researchers to choose the time and place for CAR-T cell gene activation

"We successfully used ultrasound to directly control CAR-T cells in the body for cancer immunotherapy," said Wang, a faculty member at the Institute of Medical Engineering and Nano Immunoengineering Center at the University of California, San Diego
.

Wang pointed out that the exciting thing about using ultrasound is that it can penetrate tens of centimeters under the skin, so this type of treatment has the potential to treat tumors buried deep in the body non-invasively

The team’s method involves injecting modified CAR-T cells into the tumors of mice, and then placing a small ultrasonic sensor on the skin area above the tumors to activate the CAR-T cells
.

This type of transducer uses a so-called focused ultrasound beam to focus or concentrate short pulse ultrasound energy on the tumor

The researchers tested their CAR-T cells with standard CAR-T cells
.

In the mice treated with the new CAR-T cells, only the tumors exposed to ultrasound were attacked, while other tissues in the body were not affected

Wu said: "This shows that our CAR-T cell therapy is not only effective, but also safer
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It has minimal on-target and extra-tumor side effects

This work is still in its early stages
.

Before entering clinical trials, the team will conduct more preclinical trials and toxicity studies
.

# # #

Peter Yingxiao Wang is the scientific co-founder of Cell E&G Inc.
and Acoustic Cell Therapy Inc.
and holds financial interests.
The company aims to license the technology for further development
.
These financial benefits do not affect the design, implementation or reporting of this research
.

Original Search: Nature Biomedical Engineering.
DOI 10.
1038/s41551-021-00779-w