Effects of pulmonary surfactant and surfactant protein A on phagocytosis of fractionated alveolar macrophages: relationship to starvation.
Cell Mol Biol
; 38(2): 123-30, 1992 Apr.
Article
em En
| MEDLINE
| ID: mdl-1571941
ABSTRACT
Pulmonary surfactant isolated from bronchoalveolar lavage fluid of rat lung contained a high content of surfactant protein A (SP-A) in starved for 2 days compared to fed controls, but this phenomena returned to baseline following more than 4 days starvation. As determined by immunoperoxidase staining of lung sections using SP-A antibody, SP-A could be consistently observed in nonciliated bronchiolar (Clara) cells, alveolar type II cells and some alveolar macrophages (AM). Fc receptor-mediated phagocytosis of AM was enhanced by SP-A, which was dependent on the dosis and reached a maximum at 10 micrograms of SP-A/ml. Antibody to SP-A completely inhibited the enhanced response of phagocytosis. When exposed AM subpopulations, separated into four fractions (I, II, III and IV) by discontinuous Percoll gradient, to SP-A or pulmonary surfactant prepared from rats fed and starved for 2 days enhanced their phagocytic activity in high dense cells (III and IV), particularly to SP-A and pulmonary surfactant from rats starved for 2 days. Whereas little change in lower dense fractions (I and II) were seen in all exposures except for SP-A that enhanced the cells of fraction II. These results supported the concept that pulmonary surfactant and its apoprotein, SP-A, are a factor to regulate lung defense system including activation of AM that undergo different processes following starvation.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fagocitose
/
Proteolipídeos
/
Inanição
/
Surfactantes Pulmonares
/
Macrófagos Alveolares
Limite:
Animals
Idioma:
En
Ano de publicação:
1992
Tipo de documento:
Article