IL-6 levels have been found to correlate with other autoimmune conditions, and this study provides some evidence that it is also a biomarker of NMOSD disease activity.
Currently, there are no widely accepted soluble markers for disease progression or activity of neuromyelitis optica spectrum disorder (NMOSD). This article, published in the Journal of Neuroimmunology, analyzed longitudinal interleukin (IL)-6 levels in sera of patients with NMOSD in correlation with both disease activity and brain volume. Levels were studied both during relapse and remission, and the aim of the study was to identify if and how IL-6 can serve as a biomarker of NMOSD.
IL-6 is a proinflammatory cytokine, and plays a role in the immune response by stimulating antibody production, as well as the development of effector T cells. It also disrupts blood brain barrier function and plays a role in regulating the balance between various types of immune cells. The dysregulated production of IL-6 has been associated with other autoimmune and inflammatory diseases, including rheumatoid arthritis and multiple sclerosis.
This study relied on a total of 26 patients with NMOSD, who were recruited during routine clinical follow-up or hospital stays. There were also 16 healthy controls. Among the patients with NMOSD, 88% were anti-AQP4 seropositive, and they had an average disease duration of 9.35 years. Among the patients with NMOSD, significant IL-6 elevation was found during relapse. IL-6 levels also correlated with the severity of relapse, the Expanded Disability Status Scale (EDSS) score, and brain atrophy.
The authors conclude by noting that this preliminary study suggests that IL-6 is a suitable biomarker for evaluating disease activity, in particular, relapse versus remission, and overall outcome in patients with NMOSD. More extensive studies could provide the data needed to establish IL-6 as a biomarker that can be used by physicians to provide more personalized care approaches to patients with NMOSD.
Haramati, A., Rechtman, A., Zveik, O., Haham, N., Brill, L., & Vaknin-Dembinsky, A. (2022). IL-6 as a marker for NMOSD disease activity. Journal of Neuroimmunology, 370, 577925. doi:10.1016/j.jneuroim.2022.577925