Expression and function of the angiopoietin receptor Tie-2 in human eosinophils.
J Allergy Clin Immunol
; 114(5): 1077-84, 2004 Nov.
Article
en En
| MEDLINE
| ID: mdl-15536413
ABSTRACT
BACKGROUND:
Increased vascularity of bronchial mucosa is closely related to the expression of angiogenic factors, which contribute to the pathogenesis of diseases such as asthma bronchiale.OBJECTIVE:
Here we examine the effects of the angiogenic growth factors angiopoietin 1 and angiopoietin 2 on eosinophil function in vitro and possible involvement of the angiopoietin receptor Tie-2.METHODS:
Eosinophil migration was studied by micropore filter assays. Signaling mechanisms required for angiopoietin-dependent migration were tested by using signaling enzyme blockers. Tie-2 mRNA and receptor expression on the cell surface of eosinophils was demonstrated in RT-PCR and by fluorescence-activated cell sorting analysis.RESULTS:
Angiopoietin 1 significantly stimulated eosinophil chemotaxis via activation of phosphodiesterase, phosphatidylinositol 3'-kinase, and tyrosine kinases. The effect on eosinophil migration of angiopoietin 1 was reversed by an antibody against the Tie-2 receptor and by angiopoietin 2. Incubation of eosinophils with angiopoietin 1 abolished the chemotactic effects of vascular endothelial growth factor on human eosinophils via the Tie-2 receptor. Finally, Tie-2 expression by human eosinophils was demonstrated on the transcriptional and protein level.CONCLUSIONS:
Data suggest that angiopoietin 1 stimulates directed migration and possibly inhibits vascular endothelial growth factor-induced eosinophil chemotaxis via its Tie-2 receptor, which is expressed by eosinophils. Thus, angiopoietin 1 may play an important role in the modulation of eosinophilic inflammation.
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Colección:
01-internacional
Asunto principal:
Receptor TIE-2
/
Eosinófilos
Límite:
Humans
Idioma:
En
Revista:
J Allergy Clin Immunol
Año:
2004
Tipo del documento:
Article
País de afiliación:
Austria