Expression of proteasomal immunosubunit beta1i is dysregulated in inflammatory infiltrates of minor salivary glands in Sjogren's syndrome.

Objective: Minor salivary gland specimens were analyzed to investigate dysregulation of the proteasome system in patients with Sjögren's syndrome (SS) and patients with sicca syndrome.

Methods: Labial biopsy specimens from 17 patients with SS and 11 patients with non-autoimmunesicca syndrome were analyzed by immunohistochemistry for expression of the inducible proteasomal subunits ss1i, ss2i, and ss5i. The infiltrating subsets of lymphocytes were characterized using immunofluorescence stainings against the cell-surface markers CD20 and CD27.

Autoantibodies to asialoglycoprotein receptor (ASGPR) measured by a novel ELISA--revival of a disease-activity marker in autoimmune hepatitis.

Background: The liver-specific ASGPR is an autoantigen in autoimmune hepatitis (AIH) patients. Anti-ASGPR antibody correlates with disease activity, however, only in-house assays have been reported so far.

Methods: Rabbit ASGPR was purified by affinity chromatography on galactose-Sepharose and used for standardised detection of anti-ASGPR by ELISA.

Murine CD146 is widely expressed on endothelial cells and is recognized by the monoclonal antibody ME-9F1.

The endothelium plays an important role in the exchange of molecules, but also of immune cells between blood and the underlying tissue. The endothelial molecule S-Endo 1 antigen (CD146) is preferentially located at endothelial junctions and has been claimed to support endothelial integrity. In this study we show that the monoclonal antibody ME-9F1 recognizes the extracellular portion of murine CD146.

Anti-20S proteasome autoantibodies inhibit proteasome stimulation by proteasome activator PA28.

Objective: The ubiquitin-proteasome system plays a central role in cellular homeostasis as well as in regulation of the inflammatory and stress responses. However, the occurrence of autoantibodies against 20S proteasome has, to date, been considered to be a non-specific epiphenomenon in patients with autoimmune disorders. This study was undertaken to analyze the properties of antiproteasome antibodies by investigating their influence on the proteolytic activity of the proteasome complex.