Tel Aviv University researchers discovered that white blood cells that cause allergies, called eosinophils, inhibit the growth of cancers in humans and animals. Nine days after eosinophil injection, tumor size was half that of non-injected mice.
The discovery published in Cancer Research, a journal of the American Association for Cancer Research, lead the team to exploit those allergy-causing cells’ “destructive” properties to develop new immunotherapy for cancer. Immunotherapy offers better protection against cancer than chemotherapy and has fewer side effects.
While previous research has indicated that eosinophils may be beneficial in the fight against cancer, Prof. Ariel Munitz, lead researcher of Department of Microbiology and Clinical Immunology believes his research paints the clearest picture of their potential and that his team is the first to begin creating eosinophil-based immunotherapy.
“Enhancing the number and power of T-cells is one of the main targets of immunotherapy treatments administered to cancer patients today,” Prof. Ariel Munitz said. “We discovered a new interaction that summons large quantities of T-cells to cancer tissues, and our findings may have therapeutic implications. Ultimately, our study may serve as a basis for the development of improved immunotherapeutic medications that employ eosinophils to fight cancer.”
Eosinophils create highly damaging proteins that were initially designed to combat parasites. However, in the present Western world, where high levels of sanitation have considerably reduced the risk of many parasites, eosinophils frequently have a detrimental effect on people, causing allergic and asthmatic reactions.
Given eosinophils’ destructive capacity, the researchers chose to investigate the potential benefits of these white blood cells when directed against cancer cells.
They chose to focus their research on lung metastases for two principal reasons:
“To begin, metastases, not original tumors, are frequently the primary source of difficulty in cancer treatment. The lungs are a primary site of metastasis for a variety of cancers,” Prof. Munitz explained.
“Second, we proved in a preliminary investigation that eosinophils accumulate in malignancies forming in mucous organs such as the lungs, and hence hypothesized that they would also be present in lung metastases.”
The researchers studied tissue samples obtained from patients with breast cancer. They discovered that eosinophils infiltrate the lungs and cancer tissues, where they frequently produce damaging proteins and summon T lymphocytes for reinforcement. T-cells eventually congregate in the afflicted lungs, limiting tumor growth.