Hypovitaminosis D upscales B-cell immunoreactivity in multiple sclerosis

Area of Science:

• Neuroimmunology
• Endocrinology
• Immunology

Background:

• Vitamin D is recognized as a potential regulator of multiple sclerosis (MS) disease activity.
• The specific impact of vitamin D on B lymphocytes in MS remains unclear.

Purpose of the Study:

• To assess vitamin D's effect on B-cell proliferation and cytokine secretion.
• To investigate the influence of vitamin D deficiency and supplementation on B-cell subtypes in MS patients.

Main Methods:

• Ex vivo assessment of vitamin D's impact on B-cell responses.
• Screening of B-cell subtypes in peripheral blood and cerebrospinal fluid (CSF) from MS patients and controls.
• Analysis of B-cell distribution following vitamin D supplementation in MS patients.

Main Results:

• B cells from MS patients with low vitamin D levels (<20ng/ml) showed enhanced immunoreactivity, particularly CD27(+) memory phenotypes.
• Immune responses decreased with vitamin D co-culture or after supplementation in MS patients.
• Vitamin D deficiency in MS patients correlated with lower CSF vitamin D levels, higher disease activity, and increased intrathecal CD27(+) B cells and plasma cells.

Conclusions:

• Vitamin D attenuates B-cell immunoreactivity.
• Vitamin D deficiency may contribute to MS disease activity by affecting the intrathecal compartment and increasing effector B-cell subtypes.
• Vitamin D supplementation may offer potential benefits for MS patients.