Association of antibodies against myelin and neuronal antigens with neuroinflammation in systemic lupus erythematosus.

Objectives: To determine frequency and syndrome specificity of novel and known nervous system (NS)-directed antibodies in a large, unbiased cohort of SLE patients in the Swiss SLE Cohort Study.

Methods: This retrospective pilot study included 174 patients in a cross-sectional and 102 in a longitudinal study. Antibodies against 12 NS antigens [myelin oligodendrocyte glycoprotein (MOG), neurofascin 186 (NF186), aquaporin-4 (AQP4), N-methyl-D-aspartate receptor (subunit NR1) (NMDAR-NR1), α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (subunits 1 and 2) (AMPAR1/2), gamma-aminobutyric acid B receptor (subunits B1 and B2) (GABABR1/2), glutamate decarboxylase 65 (GAD65), glycine receptor (GlyR), contactin-associated protein-like 2 (CASPR2), leucine-rich glioma-inactivated 1 (LGI1), metabotropic glutamate receptor 5 (mGluR5) and dipeptidyl-peptidase-like protein 6 (DPPX)] were screened with validated cell-based assays and correlated with clinical and diagnostic findings.

Immune complexes containing serum B-cell activating factor and immunoglobulin G correlate with disease activity in systemic lupus erythematosus.

Methods: Levels of serum BAFF, IgG anti-BAFF and BAFF-IgG complexes were quantified by enzyme-linked immunosorbent assay. IgG anti-BAFF and BAFF-IgG complexes were further characterized using serum fractions obtained by fast protein liquid chromatography. To study the association of serum BAFF, IgG anti-BAFF and BAFF-IgG complex levels with SLE manifestations, 373 visits from 178 patients prospectively included in the Swiss SLE Cohort Study were analysed.

Cathepsin S inhibition suppresses autoimmune-triggered inflammatory responses in macrophages.

In several types of antigen-presenting cells (APCs), Cathepsin S (CatS) plays a crucial role in the regulation of MHC class II surface expression and consequently influences antigen (Ag) presentation of APCs to CD4 T cells. During the assembly of MHC class II-Ag peptide complexes, CatS cleaves the invariant chain p10 (Lip10) - a fragment of the MHC class II-associated invariant chain peptide. In this report, we used a selective, high-affinity CatS inhibitor to suppress the proteolytic activity of CatS in lymphoid and myeloid cells.