Study Ties Antinuclear Antibodies to Inflammation, Relapses
That finding from a small study indicates high levels of these antinuclear antibodies were correlated with relapse status and ongoing inflammation in MS.
The study, “Antinuclear antibodies positivity is not rare during multiple sclerosis and is associated with relapsing status and IgG oligoclonal bands positivity,” was published in the journal Revue Neurologique.
Antinuclear antibodies (ANAs) — self-reactive antibodies that mistakenly attack proteins in a cell’s nucleus — are a hallmark of autoimmune conditions that are part of connective tissue diseases. These include scleroderma, rheumatoid arthritis, and lupus.
However, the prevalence of different ANAs and their clinical relevance for patients with MS remains controversial.
In this study, researchers at the University of Sfax in Tunisia measured the levels of ANAs in blood samples taken from 82 South Tunisian MS patients (mean age of 37.1 years at sampling).
More than half of the patients (79.3%) had relapsing remitting MS (RRMS), while 17 (20.7%) had progressive MS, including nine with primary progressive MS (PPMS) and eight with secondary progressive MS (SPMS).
A total of 35 patients (42.7%) tested positive for ANAs. Researchers identified proteins targeted by ANAs in seven patients. None of the patients who tested positive for ANAs had clinical signs of connective tissue diseases.
Researchers also analyzed patients’ cerebrospinal fluid (CSF) — the fluid surrounding the brain and spinal cord that can be collected during a spinal tap. Specifically, they conducted a CSF oligoclonal band screen, which indicates whether antibodies are present. The presence of antibodies is a sign of ongoing inflammation in the central nervous system (brain and spinal cord).
Patients had a positive test result when bands for at least two antibodies were detected in the CSF and absent in the blood.
In agreement with their MS diagnosis, 85.4% of patients tested positive for oligoclonal bands in their CSF. A small fraction (1.2%) had bands in both CSF and blood.
ANAs were found more frequently in patients with oligoclonal bands (47.1%) than in those without them (16.6%). Moreover, ANAs were significantly more common among patients with relapses (52.6%) than in those who were in remission (25.9%).
However, no correlation was found between ANAs and patients’ ages, sex, MS course, disease duration, degree of disability, or annual relapse rate.
Overall, the findings from this small study suggest that MS patients frequently test positive for ANAs, even though they show no clinical symptoms of diseases characterized by high ANA levels.
The presence of ANAs correlated with the presence of antibodies in the CSF and relapsing status, “probably reflecting an ongoing immune dysregulation,” the researchers wrote.
“Longer follow-up, a larger study population as well as the inclusion of control groups (other CNS inflammatory diseases) are required to support these findings,” they wrote.