Siglec-E is a negative regulator of acute pulmonary neutrophil inflammation and suppresses CD11b ß2-integrin-dependent signaling.
Blood
; 121(11): 2084-94, 2013 Mar 14.
Article
em En
| MEDLINE
| ID: mdl-23315163
ABSTRACT
Neutrophil entry into the lung tissues is a key step in host defense to bacterial and yeast infections, but if uncontrolled can lead to severe tissue damage. Here, we demonstrate for the first time that sialic acid binding Ig-like lectin E (siglec-E) functions to selectively regulate early neutrophil recruitment into the lung. In a model of acute lung inflammation induced by aerosolized lipopolysaccharide, siglec-E-deficient mice exhibited exaggerated neutrophil recruitment that was reversed by blockade of the ß2 integrin, CD11b. Siglec-E suppressed CD11b "outside-in" signaling, because siglec-E-deficient neutrophils plated on the CD11b ligand fibrinogen showed exaggerated phosphorylation of Syk and p38 mitogen-activated protein kinase. Sialidase treatment of fibrinogen reversed the suppressive effect of siglec-E on CD11b signaling, suggesting that sialic acid recognition by siglec-E is required for its inhibitory function. Siglec-E in neutrophils was constitutively associated with the tyrosine phosphatase SHP-1 and may therefore function to constitutively dampen inflammatory responses of neutrophils. These data reveal that siglec-E is an important negative regulator of neutrophil recruitment to the lung and ß2 integrin-dependent signaling. Our findings have implications for the human functional ortholog, siglec-9, and its potential role in regulating inflammatory lung disease.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Pneumonia
/
Antígenos de Diferenciação de Linfócitos B
/
Antígenos CD
/
Antígenos CD18
/
Infiltração de Neutrófilos
/
Antígeno CD11b
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Blood
Ano de publicação:
2013
Tipo de documento:
Article
País de afiliação:
Reino Unido