ASSESSMENT OF LEUKOCYTES FUNCTION IN PERIPHERAL BLOOD IN PATIENTS WITH MEDICINAL JAWS OSTEONEKROSIS

Area of Science:

• Immunology
• Oral and Maxillofacial Surgery
• Oncology

Background:

• Medication-related osteonecrosis of the jaws (MRONJ) is a serious complication associated with antiresorptive drugs like bisphosphonates.
• The precise mechanisms underlying MRONJ pathogenesis, particularly the role of immune dysfunction, require further elucidation.
• Understanding phagocyte function in MRONJ patients is crucial for developing effective treatment strategies.

Purpose of the Study:

• To assess the functional activity of peripheral blood phagocytes in patients with MRONJ.
• To investigate the impact of bisphosphonate therapy on phagocyte function.
• To explore potential new therapeutic approaches for MRONJ based on immune modulation.

Main Methods:

• Flow cytometry was used to determine the phagocytic activity of peripheral blood leukocytes.
• Patients with MRONJ, purulent-inflammatory diseases of the maxillofacial region (GVZ ChLO), and healthy controls were included.
• Phagocytic activity was measured before and 14 days after surgical treatment (osteonecrectomy).

Main Results:

• Patients with MRONJ and GVZ ChLO exhibited significantly reduced phagocytic activity (30-40% lower) compared to healthy individuals.
• Leukocyte phagocytosis indices, including stimulation by E. coli and the stimulation index (oxidative burst), were diminished in MRONJ patients.
• Phagocytic activity did not normalize 14 days post-surgery, and macrophage dysfunction was more pronounced in cancer patients on bisphosphonates.

Conclusions:

• Reduced phagocytic activity and impaired innate immunity are characteristic of MRONJ patients, potentially contributing to disease recurrence.
• Surgical intervention alone does not restore phagocyte function in MRONJ.
• Targeting immune dysfunction may offer a novel therapeutic avenue for managing MRONJ.