The Korea Advanced Institute of Science and Technology announced on July 19, 2026, that a research team led by Professor Heung Kyu Lee identified an immune mechanism for anti-CTLA-4 therapy in brain tumors. The findings were published in Science Immunology on July 10, 2025.

The study found that B cell and antibody responses initiated in tumor-draining lymph nodes are critical to the antitumor effects of anti-CTLA-4 therapy. This discovery addresses a persistent challenge in treating glioblastoma, a malignant brain tumor with frequent recurrence and poor prognosis after surgery and radiation therapy.

Immune checkpoint inhibitors have shown limited effectiveness in glioblastoma due to the immunosuppressive environment surrounding the tumor. The research team investigated the specific biological pathways that might overcome this resistance using mouse glioma models.

In these models, anti-CTLA-4 treatment reduced tumor burden and prolonged survival. The therapeutic effects of anti-CTLA-4 treatment were largely lost in mice lacking B cells, indicating that these immune cells play a central role in the therapy's success.

The B cell response increased markedly in the Deep Cervical Lymph Nodes, which receive lymphatic drainage from the brain. Germinal center B cells and T follicular helper cells increased together in the Deep Cervical Lymph Nodes during the treatment period.

The increase in B cells and T follicular helper cells was accompanied by an increase in immunoglobulin G (IgG) responses. IgG antibodies bound to the surface of glioma cells and helped macrophages remove the tumor cells.

Researchers used a dual-reporter glioma model expressing red fluorescent protein mCherry and green fluorescent protein EGFP to visualize tumor-infiltrating phagocytes engulfing glioma cells. This imaging technique allowed the team to confirm the physical interaction between immune cells and tumor tissue.

Yumin Kim served as the first author of the study. Professor Heung Kyu Lee served as the corresponding author of the study.

Professor Ji Eun Oh from the KAIST Graduate School of Medical Science and Engineering contributed to the research. The work was supported by Samsung Science and Technology Foundation grants SSTF-BA1902-05 and SSTF-BA2201-11.

The study was published in the form of a doctoral thesis at the Korea Advanced Institute of Science and Technology. The institute is a South Korean public research university established in 1971.

The identification of B cell–dependent mechanisms provides a biological explanation for the variable success of immune checkpoint inhibitors in brain cancer. By linking antibody production in deep cervical lymph nodes to tumor clearance, the research outlines a specific pathway that could be targeted to improve patient outcomes.

The publication in Science Immunology and the subsequent institutional announcement establish the findings within the broader scientific discourse on neuro-oncology. The use of dual-reporter models offers a methodological framework for future studies seeking to visualize immune-tumor interactions in real time.