Functionality of the IgA Fc receptor (FcalphaR, CD89) is down-regulated by extensive engagement of FcepsilonRI
Besides mast cells and basophils, the high-affinity IgE Fc receptor (FcepsilonRI) is exclusively expressed on certain FcalphaR (IgA Fc receptor)-expressing immune cells such as neutrophils in allergic patients. Transfected rat basophilic leukemia cell line (RBL-2H3) co-expressing FcepsilonRI and Fca...
| Veröffentlicht in: | Clinical immunology (Orlando, Fla.). - 1999. - 129(2008), 1 vom: 16. Okt., Seite 155-62 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2008
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| Zugriff auf das übergeordnete Werk: | Clinical immunology (Orlando, Fla.) |
| Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Actins Antigens, CD Bridged Bicyclo Compounds, Heterocyclic Fc(alpha) receptor Receptors, Fc Receptors, IgE Thiazolidines Phosphoric Monoester Hydrolases mehr... |
| Zusammenfassung: | Besides mast cells and basophils, the high-affinity IgE Fc receptor (FcepsilonRI) is exclusively expressed on certain FcalphaR (IgA Fc receptor)-expressing immune cells such as neutrophils in allergic patients. Transfected rat basophilic leukemia cell line (RBL-2H3) co-expressing FcepsilonRI and FcalphaR was analyzed for effects of simultaneous receptor engagement by their specific antibodies on degranulation and signaling. Whereas supraoptimal FcepsilonRI engagement decreased degranulation, which is known as a bell-shaped dose-response curve, such inhibitory effect was not observed with FcalphaR engagement. However, simultaneous engagement of FcepsilonRI and FcalphaR showed that supraoptimal FcepsilonRI engagement down-regulates FcalphaR-mediated degranulation. This inhibition was associated with extensive phosphorylation of inositol polyphosphate 5'-phosphatase SHIP1 and FcepsilonRIbeta, and reversed by adding actin-depolymerizing drug, latrunculin B. The results suggest an endogenous mechanism by which FcalphaR functionality is down-regulated in an 'allergic environment' where FcepsilonRI is co-expressed and extensively cross-linked on FcalphaR-expressing effector cells |
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| Beschreibung: | Date Completed 07.10.2008 Date Revised 24.11.2016 published: Print-Electronic Citation Status MEDLINE |
| ISSN: | 1521-7035 |
| DOI: | 10.1016/j.clim.2008.07.003 |