Decrease in cAMP levels modulates adhesion to fibronectin and immunostimulatory ability of human dendritic cells.

Dalia Burzyn; Carolina C Jancic; Sandra Zittermann; María I Keller Sarmiento; Leonardo Fainboim; Ruth E Rosenstein; H Eduardo Chuluyan

PubMed · 12101267

Decrease in cAMP levels modulates adhesion to fibronectin and immunostimulatory ability of human dendritic cells.

Dalia Burzyn·Carolina C Jancic·Sandra Zittermann·María I Keller Sarmiento·Leonardo Fainboim·Ruth E Rosenstein·H Eduardo Chuluyan

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Abstract

The aim of the present study was to analyze the early events elicited by tumor necrosis factor alpha (TNF-alpha) on monocyte-derived dendritic cells (moDC) adhesion to fibronectin (FN) and the involvement of cAMP in the signal transduction mechanism. The intracellular concentration of cAMP and moDC adhesion to FN decreased after TNF-alpha treatment. An inverted dose-dependency for TNF-alpha effect was observed for adhesion and cAMP levels. The presence of a phosphodiesterase (PDE) inhibitor (IBMX) and cAMP analogs (8Br-cAMP, Db-cAMP) reversed the observed TNF-alpha effects. The role of cAMP was analyzed further by examining the cAMP levels in nonadhered and adhered, TNF-alpha-treated moDC. Nonadhered moDC showed lower cAMP levels compared with adhered moDC. Furthermore, nonadhered moDC showed higher IL-12 content and allostimulatory ability compared with adhered moDC. The higher allostimulatory capacity was abolished in the presence of cAMP analogs and a PDE inhibitor. These results suggest that cAMP levels correlate with TNF-alpha-induced changes of moDC adhesion and allostimulatory capacity.

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Cell Adhesion Cells, Cultured Cyclic AMP Dendritic Cells Fibronectins Humans Interleukin-12 Lymphocyte Activation Monocytes Stem Cells T-Lymphocytes Tumor Necrosis Factor-alpha Journal Article Research Support, Non-U.S. Gov't

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Dalia Burzyn, Carolina C Jancic, Sandra Zittermann, María I Keller Sarmiento, Leonardo Fainboim, Ruth E Rosenstein, H Eduardo Chuluyan. 2002. Decrease in cAMP levels modulates adhesion to fibronectin and immunostimulatory ability of human dendritic cells.. https://pubmed.ncbi.nlm.nih.gov/12101267/

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