ADAM23 is a member of the brain macrophage-derived chemokine family. Structural homology of ADAM proteins suggests their function as integrin receptors. Previous studies have linked ADAM23 as a dominant contributor to brain development and cancer metastasis. The present studies now show that ADAM23 expression on DCs partially governs antigen-presentation capacities to responder CD4+ T cells. With the use of RNAi approaches, knockdown of ADAM23 in murine BMDCs resulted in impaired T cell activation, proliferation, and cytokine production. Knockdown did not alter the maturation profile of DCs (i.e., costimulatory molecule expression or production of proinflammatory cytokines) but markedly impaired cognate T cell responses. There was a significant decrease in antigen-specific clonal expansion coupled with a global decrease in Th cytokine production. Impaired early activation and proliferation did not alter/skew the balance of Th polarization but significantly depressed total levels of IL-2, IFN-γ, IL-4, and IL-17 cytokine production in CD4+ T cells primed by ADAM23 knockdown versus control DCs. Finally, neutralizing antibodies targeting the α(v)β(3) integrin receptors resulted in similar phenotypes of impaired CD4+ T cell responses. Taken together, these studies show a novel role of ADAM23 in governing DC antigen presentation to cognate CD4+ T cells.
CD123hi CD11c− dendritic cells (CD123hi DC) are a distinct subset of human DC present in bone marrow, blood, lymphoid organs, and peripheral tissues. Pathogen stimulation, cytokine, or CD40 ligation induces CD123hi DC maturation, involving a shift from their innate immune to cognate antigen-presenting functions. In this study, we revealed that blood CD123hi DC in the presence of cytokine (granulocyte macrophage-colony stimulating factor and interleukin-3) undergo progressive, step-wise maturation through an “early” stage, delineated by expression of the antigen detected by the new monoclonal antibody CMRF58 (CD123hiCMRF58+CD40−CD86−CD83−) to the “late” stage with costimulatory antigen expression (CD123hiCMRF58+CD40+CD86+CD83+/−). In this early stage, cytokine-maintained CD123hi DC do not display changes in their morphology, no longer produce interferon-α (IFN-α) in response to bacteria, and develop the capacity to induce proliferation and polarization of allogeneic T cells. CD123hiCMRF58+ DC, phenotypically similar to in vitro cytokine-maintained CD123hi DC, were not detected in tonsil but are present in allergen-challenged nasal mucosa of allergic individuals. Thus, CD123hi DC in certain tissue environments such as allergen-challenged nasal mucosa share a common CD123hiCMRF58+ phenotype with in vitro cytokine-maintained blood CD123hi DC characterized by lack of IFN-α production.
more » « less- NSF-PAR ID:
- 10395722
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Leukocyte Biology
- Volume:
- 77
- Issue:
- 3
- ISSN:
- 0741-5400
- Page Range / eLocation ID:
- p. 344-351
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Backgrounds To explore the expression and functions of the tripartite motif‐containing protein 21 (TRIM21) in oral lichen planus(OLP) lesions.
Methods Paraffin sections of buccal mucosa samples from 15 cases of reticular oral lichen planus (OLP) patients and 10 healthy controls were used for immunohistochemistry to determine expression and distribution of TRIM21. Buccal mucosae from 11 OLP patients and seven healthy controls were analyzed by qPCR to quantify its gene expression. Peripheral blood mononuclear cells and CD3+ cells from four pairs of age‐ and sex‐matched OLP patients and healthy controls were isolated for immunocytochemistry and culture. Following lentivirus‐mediated overexpression of TRIM21 gene in CD3+ cells, CCK‐8 was applied to evaluate cell proliferation. Cytokines including IL‐2, IL‐4, IL‐5, IL‐6, IL‐10, TNF‐α, and IFN‐γ in the supernatants were measured by the cytometric bead array and verified by ELISA.
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Basic Protocol 1 : Seeding enteroid fragments onto Transwells for monolayer formationAlternate Protocol : Seeding enteroid fragments for monolayer formation using triturationBasic Protocol 2 : Isolation of monocytes and derivation of immune cells from human peripheral bloodBasic Protocol 3 : Isolation of neutrophils from human peripheral bloodBasic Protocol 4 : Assembly of enteroid/macrophage or enteroid/neutrophil co‐culture -
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