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Updated: Aug 8, 2026
Culture of myeloid dendritic cells from bone marrow precursors
Published on: July 26, 2008
CD83 is preformed inside monocytes, macrophages and dendritic cells, but it is only stably expressed on activated
Weiping Cao1, Szu Hee Lee, Jinhua Lu
1Department of Microbiology, Faculty of Medicine, National University of Singapore, Blk MD 4, 5 Science Drive 2, Singapore 117597.
Insights
Human dendritic cells (DCs) rapidly express surface CD83 upon activation. This process involves preformed intracellular CD83 and post-translational regulation, particularly glycosylation, rather than new protein synthesis.
Area of Science:
- Immunology
- Cell Biology
Background:
- Dendritic cells (DCs) are crucial immune regulators.
- CD83 is a cell surface marker indicating DC activation.
- The precise mechanisms of CD83 expression remain incompletely understood.
Purpose of the Study:
- To investigate the kinetics and regulation of CD83 expression on DCs, monocytes, and macrophages.
- To compare CD83 induction with other activation markers during DC maturation.
- To elucidate the post-translational modifications involved in CD83 surface expression.
Main Methods:
- Flow cytometry and Western blotting to detect CD83 expression.
- Indirect immunofluorescence microscopy to localize intracellular CD83.
- Functional assays using inhibitors like brefeldin A and tunicamycin.
- Enzymatic deglycosylation using PNGase F.
Main Results:
- CD83 is rapidly induced on the surface of activated DCs, monocytes, and macrophages, preceding other activation markers.
- Intracellular, preformed CD83 exists in immature DCs, monocytes, and macrophages.
- Rapid surface expression is independent of de novo protein synthesis but requires glycosylation.
- Different CD83 glycoforms (37 and 50 kDa) are observed, with mature DCs predominantly expressing the 50 kDa form.
Conclusions:
- Monocytes, macrophages, and immature DCs store preformed intracellular CD83.
- Rapid surface expression of CD83 upon activation is a post-translational event, primarily regulated by glycosylation.
- CD83 glycosylation status differentiates between immature and mature DCs.
Abstract:
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.
