TCR repertoire diversity in Multiple Sclerosis: High-dimensional bioinformatics analysis of sequences from brain, cerebrospinal fluid and peripheral blood.

BACKGROUND: T cells play a key role in the pathogenesis of multiple sclerosis (MS), a chronic, inflammatory, demyelinating disease of the central nervous system (CNS). Although several studies recently investigated the T-cell receptor (TCR) repertoire in cerebrospinal fluid (CSF) of MS patients by high-throughput sequencing (HTS), a deep analysis on repertoire similarities and differences among compartments is still missing. METHODS: We performed comprehensive bioinformatics on high-dimensional TCR Vß sequencing data from published and unpublished MS and healthy donors (HD) studies. We evaluated repertoire polarization, clone distribution, shared CDR3 amino acid sequences (CDR3s-a.a.) across repertoires, clone overlap with public databases, and TCR similarity architecture. FINDINGS: CSF repertoires showed a significantly higher public clones percentage and sequence similarity compared to peripheral blood (PB). On the other hand, we failed to reject the null hypothesis that the repertoire polarization is the same between CSF and PB. One Primary-Progressive MS (PPMS) CSF repertoire differed from the others in terms of TCR similarity architecture. Cluster analysis splits MS from HD. INTERPRETATION: In MS patients, the presence of a physiological barrier, the blood-brain barrier, does not impact clone prevalence and distribution, but impacts public clones, indicating CSF as a more private site. We reported a high Vß sequence similarity in the CSF-TCR architecture in one PPMS. If confirmed it may be an interesting insight into MS progressive inflammatory mechanisms. The clustering of MS repertoires from HD suggests that disease shapes the TCR Vß clonal profile. FUNDING: This study was partly financially supported by the Italian Multiple Sclerosis Foundation (FISM), that contributed to Ballerini-DB data collection (grant #2015 R02).

CSF/serum matrix metallopeptidase-9 ratio discriminates neuro Behçet from multiple sclerosis.

In neuro Behçet disease with multiple sclerosis-like features, diagnosis could be challenging. Here, we studied the cerebrospinal fluid and serum inflammatory profile of 11 neuro Behçet and 21 relapsing-remitting multiple sclerosis patients. Between the soluble factors analyzed (MMP9, TNF α, IL6, CXCL13, CXCL10, CXCL8, IFN γ, IL10, IL17, IL23, and others) we found MMP9 increased in neuro Behçet serum compared to multiple sclerosis and decreased in cerebrospinal fluid. Furthermore, neuro Behçet analysis of circulating natural killer CD56DIM subset suggests their potential involvement in increased MMP9 production. We believe that these findings may have a translational utility in clinical practice.