Serum levels of soluble Fas/APO-1 (CD95) and its molecular structure in patients with systemic lupus erythematosus (SLE) and other autoimmune diseases

Abstract

SUMMARYThere are two major forms of the Fas molecule, membranous Fas and soluble Fas (sFas). To clarify the clinical significance of sFas in autoimmune diseases, we designed a sandwich ELISA to determine serum concentrations of sFas and its molecular structure, and we then analysed the correlation between levels of sFas and laboratory findings in patients with SLE and other autoimmune diseases. The levels of serum sFas were significantly higher in SLE patients than in subjects with other autoimmune diseases and in healthy donors, and the frequency of a positive serum sFas was much greater in SLE patients with high SLE disease activity index scores than in those with low scores. In addition, sFas-positive SLE patients showed a significant difference in various laboratory parameters from sFas-negative SLE patients. Serial measurements of serum sFas levels in SLE patients with active disease revealed that the elevated level of sFas dramatically decreased with improvement in clinical and laboratory findings, following corticosteroid therapy. We propose that the serum level of sFas can serve as an appropriate marker for evaluating SLE disease activity. Serum sFas is heterogeneous with respect to molecular structure, thus several mechanisms are involved in the generation of sFas.

Two Cases of Myelodysplastic Syndrome with Extramedullary Polyclonal Plasma Cell Proliferation and Autoantibody Production: Possible Role of Soluble Fas Antigen for Production of Excessive Self-Reactive B Cells.

“…The levels of soluble Fas antigen were higher in patients with SLE than in patients with other autoimmune diseases and healthy subjects. Furthermore, the frequency ofa positive serum soluble Fas antigen was much greater in patients with higher disease activity, and serial determination of the serum Fas antigen levels demonstrated their parallel changes with the disease activity (21). These findings supported the significance of soluble Fas antigen in the pathogenesis of autoimmune disease.…”

The alteration of fas receptor and ligand system in hepatocellular carcinomas: How do hepatoma cells escape from the host immune surveillancein vivo?

“…The serum concentrations of sFas and sFasL were measured by sandwich enzyme-linked immunosorbent assay as described previously. 38,42 For the assay of sFas, DX-3 and DX-2 were used as capture monoclonal antibody (MoAb) and detector MoAb, respectively, and 4H9 and 4A5 were used for sFasL. Briefly, Nunc Immuno-model Maxisorb-plates (Nunc, Inc., Naperville, IL) were coated with 50 µL of capture MoAb (10 µg/mL) overnight at 4°C, followed by blocking of the free sites with 100 µL of Block Ace (Dainihon Pharmaceutical Co., Osaka, Japan) for 2 hours.…”

The soluble CD40 ligand sCD154 in systemic lupus erythematosus

“…On the other hand, soluble proteins released from activated T cells may contribute to immune activation (20)(21)(22)(23). TNF-α, for example, is a protein that can exist as either a soluble molecule or a membrane-associated glycoprotein (24)(25)(26).…”