Serum concentration of CD40L is elevated in inflammatory demyelinating diseases

•Serum concentration of CD40L is elevated in MS and NMO patients.•There is a correlation between CD40L and humoral immunity in inflammatory demyelinating disease.•MS and NMO patients with abnormal thyroid function seem to have high levels of serum CD40L.

It is believed that auto-inflammatory activity, including cellular and humoral immunity responses, especially T cell–B cell collaboration, is one of the most important components of the pathogenesis of inflammatory demyelinating disease. CD40L is critical for T cell–B cell collaboration. Actually, serum CD40L levels have been shown to increase in MS. In the present study, serum CD40L levels were measured by an enzyme-linked immunosorbent assay (ELISA) in NMO (n = 27) and MS (n = 19) patients and controls (n = 14). We revealed elevation of CD40L in NMO patients, and discovered a correlation between CD40L and humoral immunity in inflammatory demyelinating disease.