Treatment of alveolar macrophages with cytochalasin D inhibits uptake and subsequent growth of Legionella pneumophila.
AUTOR(ES)
Elliott, J A
RESUMO
Legionella pneumophila multiplied rapidly in guinea pig and rat alveolar macrophages but failed to grow when phagocytic activity was inhibited by pretreatment with 0.5 or 1.0 microgram of cytochalasin D per ml. Attachment was not inhibited by cytochalasin D. No extracellular multiplication occurred when L. pneumophila were in close proximity to viable functional macrophages or even when the bacteria were attached to plasma membranes of the macrophages. Nonopsonized L. pneumophila were avidly phagocytized by alveolar macrophages. When bacteria were centrifuged onto a cell pellet, more than 85% of the phagocytes contained one or more bacteria within 15 min. In contrast, under the same conditions only approximately 15% of the macrophages contained nonopsonized Escherichia coli or Staphylococcus aureus. Phagocytosis of L. pneumophila by untreated guinea pig macrophages occurred by extension of pseudopodia around the bacteria in a classical manner. The failure of the bacteria to actively penetrate the phagocyte suggests that their intracellular survival must not depend on avoidance of a phagosome but rather on an inhibition of or resistance to subsequent microbicidal functions of the macrophage.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=261061Documentos Relacionados
- Interaction of primate alveolar macrophages and Legionella pneumophila.
- Cyanobacterial stimulation of growth and oxygen uptake by Legionella pneumophila.
- Liquid medium for growth of Legionella pneumophila.
- Roles for tumor necrosis factor alpha and nitric oxide in resistance of rat alveolar macrophages to Legionella pneumophila.
- Oropharyngeal colonization with Legionella pneumophila.