Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.5.1.52 (PNGase F)
 1,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human DCs (dendritic cells) express surface CD83 upon activation. Comparing the surface induction of CD83 with the upregulation of CD40, CD80 and CD86 during LPS (lipopolysaccharide)-induced DC maturation showed that CD83 induction occurred more rapidly. Despite the lack of CD83 on immature DCs, it was detected in these cells by Western blotting and flow cytometry. Indirect immunofluorescence revealed CD83 inside immature DCs in perinuclear regions. CD83 was absent on monocytes and macrophages, but it was detected inside these cells and found to be rapidly surface-expressed upon LPS-induced activation. Whereas CD83 expression on activated DCs was sustainable, its expression on monocytes and macrophages was transient. Optimal interleukin-4 co-stimulation during DC generation from monocytes was found to be essential for stable CD83 surface expression. CD83 was detected as 37 and 50 kDa forms in transfected 293T cells. Macrophages and immature DCs expressed the 37 kDa form, whereas mature DCs predominantly expressed the 50 kDa form. In monocytes, CD83 was detected as a 22 kDa detergent-insoluble form. The rapid CD83 surface induction on DCs and macrophages was blocked by brefeldin A, but not by cycloheximide, showing that fresh CD83 synthesis was not essential. Tunicamycin inhibited the expression of the 50 and 37 kDa CD83 forms, and also blocked CD83 surface expression on DCs and macrophages. PNGase F (peptide N-glycosidase F) digestion reduced the 37 and 50 kDa CD83 forms to 28 kDa. In summary, monocytes, macrophages and immature DCs contain preformed intracellular CD83, and its rapid surface expression upon activation is post-translationally regulated in a process involving glycosylation.
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PMID:CD83 is preformed inside monocytes, macrophages and dendritic cells, but it is only stably expressed on activated dendritic cells. 1532 Aug 71

The cell surface protein CD83 belongs to the immunoglobulin superfamily and is highly expressed on mature dendritic cells. The soluble form of CD83, sCD83, is a potential immune suppressor. In a previous study, recombinant soluble CD83 was expressed in Escherichia coli, resulting in a lack of functional glycosylation. Although eukaryotic cell systems for producing sCD83 offer the advantages of protein processing, folding, and posttranslational modification, these systems are complicated, expensive, and produce low levels of protein. To obtain more efficient expression of sCD83, we expressed human sCD83 fused with fragment crystallizable region of human IgG1 (hIgG1 Fc) in Pichia pastoris. Under the optimal conditions (time of induction, 48 h; inoculum density (OD600), 80; concentration of methanol, 3.0 %; pH 7.0-8.0; concentration of casamino acid, 5.0 %), the purified human sCD83-hIgG1 Fc (hsCD83-Ig) fusion protein existed as dimers at 25-30 mg/L culture. Treatment with PNGase F showed that purified hsCD83-Ig was modified by N-linked glycosylation. Moreover, the hsCD83-Ig expressed in the P. pastoris system could suppress lymphocyte proliferation in ConA-stimulated and one-way mixed lymphocyte reaction systems. Thus, hsCD83-Ig expressed in P. pastoris is functional and may be used in experimental therapies for graft rejection, graft-versus-host disease, and autoimmune diseases.
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PMID:Production and characterization of human soluble CD83 fused with the fragment crystallizable region of human IgG1 in Pichia pastoris. 2339 67

CD83 is a highly glycosylated type I transmembrane glycoprotein that belongs to the immunoglobulin superfamily. CD83 is upregulated during dendritic cell (DC) maturation, which is critical for the initiation of adaptive immune responses. The soluble isoform of CD83 (sCD83) is encoded by alternative splicing from full-length CD83 mRNA and inhibits DC maturation, which suggests that sCD83 acts as a potential immune suppressor. In this study, we developed a sound strategy to express functional sCD83 from Pichia pastoris in extremely high-density fermentation. Purified sCD83 was expressed as a monomer at a yield of more than 200 mg/L and contained N-linked glycosylation sites that were characterized by PNGase F digestion. In vitro tests indicated that recombinant sCD83 bound to its putative counterpart on monocytes and specifically blocked the binding of anti-CD83 antibodies to cell surface CD83 on DCs. Moreover, sCD83 from yeast significantly suppressed ConA-stimulated PBMC proliferation. Therefore, sCD83 that was expressed from the P. pastoris was functionally active and may be used for in vivo and in vitro studies as well as future clinical applications.
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PMID:The expression and characterization of functionally active soluble CD83 by Pichia pastoris using high-density fermentation. 2458 42