Elevated levels of soluble CD26 and CD30 in multiple sclerosis

<p>Objective The activation of autoreactive T cells is a major event in the initiation of autoimmune responses in multiple sclerosis (MS). In addition to the T cell receptor stimulation, optimal activation of T cells requires various costimulatory molecules, such as CD26 and CD30, which has not been extensively studied in MS. Our aim was to explore whether the circulating levels of CD26 and CD30 in sera are associated with MS subtypes, inflammatory disease activity and disability in MS patients. Methods The study included 195 participants: 39 relapsing-remitting MS patients, 19 secondary-progressive MS patients, 19 clinically isolated syndrome patients, 58 controls for sCD26 analysis and 60 for sCD30 analysis. The levels of sCD26 and sCD30 in sera were analyzed using enzyme-linked immunosorbent assay, and the levels of interleukin-10, tumor necrosis factor-α and interferon-γ were analyzed with the Luminex assay. Results We observed increased levels of sCD26 and sCD30 in relapsing-remitting MS, secondary-progressive MS, and clinically isolated syndrome patients compared with the controls (P <0.05). Furthermore, elevated levels of sCD30 were noticed in treated relapsing-remitting MS patients than in untreated patients (P = 0.016), and also in converted CIS patients than in unconverted patients (P = 0.009). Although sCD26 and sCD30 could not associate with clinical measures, such as the disability score or disease activity, the levels of sCD30 correlated positively with interleukin-10 levels (r = 0.583, P <0.0001) and sCD26 levels (r = 0.262, P = 0.046) in MS patients. Conclusion The present results suggest that the elevated levels of sCD30 are associated with the regulatory immune responses predisposing to clinically stable phase of MS.</p>