Johns Hopkins scientists are reporting tiny magnetic particles can boost the effectiveness of immunotherapy, offering a promising new treatment that trains the body's immune system to better fight cancer and infections.

In a study published in the journal ACS Nano, Johns Hopkins investigators demonstrated the technique boosted white blood cells — known as killer T cells because of their potential as an effective weapon against cancer, as well as infectious diseases — in mice.

"The challenge has been to train these cells efficiently enough, and get them to divide fast enough, that we could use them as the basis of a therapy for cancer patients,” said Jonathan Schneck, M.D., a professor of pathology, medicine, and oncology at the Johns Hopkins University School of Medicine's Institute for Cell Engineering. “We've taken a big step toward solving that problem."

The researchers found exposing T cells to magnetic nanoparticles primed them to more effectively battle tumors and divide rapidly to form more T cells.

"The [technique provides] the foundation for simplifying and streamlining the process of generating tumor-specific T cells for use in immunotherapy," said Juan Carlos Varela, M.D., a former member of Dr. Schneck's laboratory who is now an assistant professor at the Medical University of South Carolina.

While the team tested the new method only on cancer, Dr. Schneck says it could also potentially work for therapies against chronic infectious diseases, such as HIV. He added that clinical trials of the technique could begin within two years.