DZNE Researchers Use Infrared Three-Photon Microscopy to Track Microglia-Glioblastoma Interactions in the Living Brain

DZNE study reveals that microglia immune cells actively influence glioblastoma spread, suggesting new therapeutic targets for aggressive brain cancer.

By: AXL Media

Published: Apr 21, 2026, 9:56 AM EDT

Source: Information for this report was sourced from EurekAlert!

Capturing the Cellular Mechanics of Brain Cancer Infiltration

Glioblastoma is recognized as the most aggressive form of adult brain cancer, largely due to its ability to infiltrate healthy tissue far beyond the primary tumor site. To better understand this process, a research team from the DZNE, University Hospital Bonn, and the Cluster of Excellence “ImmunoSensation” utilized three-photon microscopy to observe the living brain. This advanced imaging technique, which employs infrared light, allowed the scientists to visualize the "far infiltration zone"—a region located several millimeters away from the main tumor mass. The study, published in the journal Immunity, provides a rare look at how cancer cells interact with the brain's internal environment during the early stages of spread.

The Role of Microglia as Active Modulators of Tumor Spread

Microglia are the resident immune cells of the brain, traditionally viewed as sentinels that patrol for threats. However, the new findings suggest these cells are far from passive observers in the presence of glioblastoma. The researchers observed that the behavior of microglia is highly dynamic and dependent on the density of the invading cancer cells. When only a few tumor cells are present, microglia demonstrate increased motility and heightened surveillance activity. This suggests an initial attempt by the immune system to recognize and perhaps contain the malignant threat before it establishes a firmer foothold in the surrounding neural tissue.

Declining Immune Response Amidst Intensifying Infiltration

As the concentration of glioblastoma cells increases within the infiltration zone, the protective behavior of the microglia appears to falter. The study revealed that as tumor presence intensifies, the once-active immune response begins to decline, characterized by a reduction in microglial motility. To further investigate this phenomenon, the team experimented with disabling specific receptors that microglia use to sense their surroundings and conducted pharmacological depletion to reduce the number of immune cells. These interventions confirmed that the crosstalk between the immune cells and the cancer is a primary driver of how effectively the tumor can invade new areas of the brain.