Scientists have developed a simplified nanoparticle system capable of “training” the immune system to locate and destroy disease-causing cells. The new technology could become a more accessible alternative to complex and expensive cellular immunotherapy methods currently used, for example, to treat certain types of blood cancer. The findings were published in Science Advances.

The technology was created by researchers from the Johns Hopkins University School of Medicine. They engineered biodegradable polymer nanoparticles—chains of molecules that can safely break down in the body. The surface of these particles is coated with antibodies that allow them to locate and activate T cells, the key “fighters” of the immune system.

Once inside the body, the nanoparticles interact with T cells and deliver mRNA molecules into them. These genetic instructions cause immune cells to produce special receptors capable of recognizing and attacking pathological B cells. Such cells play a major role in several diseases, including the autoimmune condition Lupus, as well as certain blood cancers such as Leukemia and Lymphoma.

Experiments in mice produced striking results: just 24 hours after a single injection, the number of targeted B cells in the blood dropped by about 95 percent. In the spleen—one of the immune system’s key organs—about half of these cells were also eliminated. At the same time, B-cell levels partially recovered after a week, suggesting the possibility of controlled modulation of the immune response.

One of the main advantages of the technology is its relative simplicity. Unlike modern CAR‑T therapy, in which a patient’s immune cells are first extracted, genetically modified in a laboratory, and then returned to the body, the new system could function as a ready-to-use drug. This could potentially make treatment faster, cheaper, and more widely accessible for patients.