Phagocytosis, macropinocytosis and antigen presentation by dendritic cells (
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.
more » « less- NSF-PAR ID:
- 10391756
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Journal of Leukocyte Biology
- Volume:
- 100
- Issue:
- 5
- ISSN:
- 0741-5400
- Page Range / eLocation ID:
- p. 855-864
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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