Determination of the inhibitory activity and biological half-live of soluble CD83: comparison of wild type and mutant isoforms.

A soluble form of CD83 ("sCD83") has been shown to block DC-mediated T cell stimulation in vitro and an immunosuppressive role has also been shown in vivo using an experimental-autoimmune-encephalomyelits (EAE) model. Using recombinant mutational analyses, recently, we could show that sCD83 forms a homo-dimer, whereby four cysteines are involved in the intra-molecular disulfide bonds and the fifth cysteine is responsible for the inter-molecular bridging of the two molecules. Further studies revealed that the two CD83-isoforms, i.

Prevention and treatment of experimental autoimmune encephalomyelitis by soluble CD83.

CD83 is up-regulated on the surface of dendritic cells (DCs) during maturation and has been widely used as a marker for mature DCs. Recently, we reported the recombinant expression of the extracellular immunoglobulin domain of human CD83 (hCD83ext). Using this soluble form of CD83, allogeneic as well as specific cytotoxic T lymphocyte proliferation could be blocked in vitro.

Role of CD83 in the immunomodulation of dendritic cells.

Glycoprotein CD83 is one of the best-known maturation markers for human dendritic cells (DCs). The fact that CD83 is strongly upregulated together with co-stimulatory molecules such as CD80 and CD86 during DC maturation suggests it plays an important role in the induction of immune responses. Infection studies with herpes simplex virus type 1 (HSV-1) and the inhibition of the CD83 mRNA specific transport from the nucleus to the cytoplasm suggested a possible functional role for CD83.

Cloning and characterization of the promoter region of the human CD83 gene.

Human CD83 (hCD83) is a glycoprotein expressed predominantly on the surface of dendritic cells (DC). To get insight into the regulation of hCD83 expression, we cloned a 3037 bp fragment up-stream of the translation initiation codon. Deletion mutants were constructed revealing highest promoter activity in the -261 fragment containing four SP1 binding sites and one NF-kappaB element.