Smart Immune Cells: Tumor Destruction Breakthrough
USC engineers have revolutionized cancer treatment wiht EchoBack CAR T-cells, a cutting-edge CAR T-cell therapy designed to precisely target and destroy solid tumors.Unlike conventional methods, these smart immune cells, activated by ultrasound, can attack tumors for five days, offering enhanced efficacy and safety. This breakthrough in cancer immunotherapy, published in Cell, marks a meaningful step forward in treating previously resistant cancers. Pioneering research, led by Peter Yingxiao Wang, utilizes ultrasound control, potentially reducing treatment frequency. These innovative T-cells show great promise,particularly against prostate cancer. News Directory 3 is excited to cover this groundbreaking advancement in medical science. Could this lead the charge in personalized cancer treatment? Discover what’s next …
USC Engineers develop EchoBack CAR T-Cell Therapy for Solid Tumors
Updated June 27,2025
Los Angeles-USC biomedical engineers have engineered a new type of immune cell,the “EchoBack CAR T-cell,” designed to target and destroy solid tumors with unprecedented precision. This innovative cancer immunotherapy approach, detailed in the journal Cell, offers a potential breakthrough in treating cancers previously resistant to immunotherapy, while safeguarding healthy tissues.
CAR T-cell therapy, which has shown success against blood cancers like leukemia, involves extracting a patient’s T-cells, genetically modifying them to enhance thier cancer-fighting abilities, and then reintroducing them into the body. Peter Yingxiao Wang leads pioneering research in this area at USC’s alfred E. Mann Department of Biomedical Engineering.
The Wang Lab’s latest innovation, the echoback CAR T-cell, can attack tumor cells five times longer than conventional CAR T-cells.Focused ultrasound remotely controls these cells, possibly increasing treatment safety and efficacy. This novel role for ultrasound in cancer therapy could revolutionize treatment protocols.
Longwei Liu, assistant professor at the USC Viterbi School of Engineering and lead author, explained that first-generation ultrasound-controllable CAR T-cells typically attacked cancer cells for only 24 hours. The EchoBack CAR T-cells, however, remain active for at least five days after ultrasound activation at the tumor site.
Liu noted the reduced treatment frequency as a major benefit. “With first-generation cells, patients might need daily hospital visits. The new generation could reduce visits to once every two weeks, or even less.”
Wang hailed the development as a “breakthrough,” making ultrasound-controllable CAR T-cells practical for real-world medical use.
The focused ultrasound acts as an “on switch,” triggering the CAR T-cells to recognize and attack cancer cells after a brief, 10-minute pulse.
Wang emphasized the long-lasting effect of the ultrasound stimulation, enabling the cells to effectively kill tumors locally. “It’s a milestone, migrating from conceptual design to a practical application system,” he said.
The cells are named ’EchoBack-CAR’ due to their unique mechanism that echoes the ultrasound stimulation. This feedback function allows them to react to tumor cells, triggering activation and attack.
“When a tumor cell is nearby, it signals our CAR T-cell, which then produces more killing molecules,” liu explained.”This also enhances safety, as the CAR molecule degrades when the T-cells migrate out of the tumor, preventing harm to normal tissue. We’ve engineered them to be smart CAR T-cells.”
Lab experiments in mouse models tested the new CAR T-cells against prostate cancer and glioblastoma cells.
“The ultrasound controllable CAR, with two rounds of stimulation, outperformed standard CAR T-cells,” Liu said. “When challenged repeatedly with tumor cells, standard CAR T-cells became weary, while our ultrasound controllable CAR maintained better function, less exhaustion, and enhanced killing.”
USC Viterbi PhD students Peixiang He and Yuxuan Wang contributed considerably. The team collaborated with Yale University and the University of north Carolina at Chapel Hill for single-cell sequencing. Qifa Zhou, a Zohrab A. Kaprielian Fellow in Engineering at USC, provided ultrasound technology expertise.
What’s next
The team hopes to adapt this technology to treat other solid tumors, such as breast cancer and retinoblastoma, offering a modular tool for future immunotherapy applications. Liu envisions a future where “smart” CAR T-cells, responsive to ultrasound and tumor signals, provide meaningful benefits to patients.