Complement biomarkers, including complement factor H (CFH), Ba, and sC5b-9, present in the peripheral blood of neuromyelitis optica spectrum disorder patients, can aid in understanding the disease’s status.
The complement system is implicated in the pathogenesis of neuromyelitis optica spectrum disorder (NMOSD). Recently, eculizumab, a humanized anti-C2 monoclonal antibody, was utilized in treating neuroimmune diseases. This study investigated the role of biomarkers in predicting the activation of complement pathways, which may also offer insight into the pathogenesis and prognosis of the disease.
The study concluded that complement biomarkers in the peripheral blood, including complement factor H (CFH), Ba, and sC5b-9, can aid in understanding the status of the disease. The study findings are published in the journal Frontiers in Immunology.
Baseline Characteristics of Study Participants
The study included 21 NMOSD patients and 25 patients diagnosed with Guillain–Barre syndrome (GBS). The mean age was 48.0 years in the NMOSD patients and 50.8 years in the GBS patients. Anti-glycolipid and anti-aquaporin 4 (AQP4) antibodies were positive in 88% of GBS and 81% of NMOSD patients.
Complement Biomarker Levels in NMOSD and GBS Patients
The levels of sC5b-9 in the acute phase of patients with NMOSD were significantly higher than those of patients with GBS. This indicates progression of the complement system to the terminal pathway in the acute phase of NMOSD. Furthermore, the levels of serum Ba were higher in both GBS and NMOSD during the acute phase. A complement regulatory protein, complement factor H (CFH), was significantly lower among NMSOD patients compared to GBS patients and healthy controls. Complement factor I (CFI) levels were also higher among GBS and NMOSD patients compared to healthy controls.
Correlation of Complement Biomarker Levels in NMOSD and GBS Patients
The correlational analysis demonstrated a positive correlation between Ba and sC5b-9 levels and a negative correlation between CFI and CFH levels.
Changes of Complement Biomarker Levels in Acute and Remission Phases
There were no changes in the main laboratory investigations across the acute and remission phases. The levels of Ba and sC5b-9 biomarkers demonstrated a significant reduction in the remission phase, which were previously elevated during the acute phase. The average CFH levels remained lower in the NMOSD patients compared to healthy controls during both acute and remission phases. Some of the patients demonstrated a marked reduction in CFH levels during the remission phases. The CFI levels decreased during the remission phase; however, the average CFI levels were higher among healthy controls in the remission phase.
Biomarker Levels in GBS Remain Stable
On the contrary, GBS patients did not demonstrate changes in the complement biomarker levels across the acute and remission phases. A moderately positive correlation exists between the duration of the disease and the CFI levels.
Complement biomarkers, including CFH, Ba, and sC5b-9, present in the peripheral blood of neuromyelitis optica spectrum disorder patients, can aid in understanding the disease’s status.
Source
Miyamoto, K., Minamino, M., Kuwahara, M., Tsujimoto, H., Ohtani, K., Wakamiya, N., Katayama, K., Inoue, N., & Ito, H. (2023). Complement biomarkers reflect the pathological status of neuromyelitis optica spectrum disorders. Frontiers in Immunology, 14. https://doi.org/10.3389/fimmu.2023.1090548
