IL-5 accounts for the mouse pleural eosinophil accumulation triggered by antigen but not by LPS.
The involvement of interleukin-5 (IL-5) in the pleural eosinophilia induced by LPS or allergen was investigated. The number of pleural eosinophils in actively sensitized mice increased 24 h after the intrathoracic (i.t.) injection of ovalbumin (12 mg/cavity), peaked within 72 h, and persisted significantly increased for at least 120 h. Despite being less intense, the i.t. injection of LPS (250 ng/cavity) also increased the number of pleural eosinophils at 24 h, returning to basal levels within 72 h. Intraperitoneal pretreatment with monoclonal antibody to IL-5 (TRFK-4 and TRFK-5, 500 mg/kg) suppressed the eosinophil accumulation induced by IL-5 (200 units/cavity) or ovalbumin, but had no effect on the LPS-induced eosinophilia. Transfer of the cell-free pleural washing from LPS-treated donor mice to naive recipient animals led to a selective increase in the eosinophil counts. The co-incubation of the pleural washing from LPS-treated animals with monoclonal antibody to IL-5 failed to modify the phenomenon. The results indicate that IL-5 plays an important role in the antigen-induced accumulation of eosinophils in vivo, but not in the eosinophilia triggered by LPS.
Bozza
P T
PT
Departamento de Fisiologia e Farmacodinâmica, Instituto Oswaldo Cruz/FIOCRUZ, Rio de Janeiro, Brazil.
Castro-Faria-Neto
H C
HC
Penido
C
C
Larangeira
A P
AP
Silva
P M
PM
Martins
M A
MA
Cordeiro
R S
RS
D000818:Animals; D000911:Antibodies, Monoclonal; D002631:Chemotactic Factors, Eosinophil / Q000032:analysis / Q000502:physiology*; D015848:Interleukin-5 / Q000032:analysis / Q000276:immunology / Q000502:physiology*; D008070:Lipopolysaccharides / Q000276:immunology*; D008297:Male; D051379:Mice; D010047:Ovalbumin / Q000276:immunology*; D010998:Pleurisy / Q000276:immunology*
D000911:Antibodies, Monoclonal; D002631:Chemotactic Factors, Eosinophil; D015848:Interleukin-5; D008070:Lipopolysaccharides; D010047:Ovalbumin