Altered surfactant protein B levels in transgenic mice do not affect clearance of bacteria from the lungs.
To determine the role of surfactant protein B (SP-B) in bacterial clearance from the airways, three groups of mice expressing different levels of SP-B were studied: wild-type mice, hemizygous SP-B mice, and SP-B overexpressing transgenic mice. SP-B levels in overexpressing mice were increased 5-fold relative to hemizygous mice and 2- to 3-fold over wild-type littermates. Mice from each group were infected intratracheally with the common airway pathogens, group B streptococci or Pseudomonas aeruginosa. There was no significant difference in the number of recoverable viable bacteria at 6 h (group B streptococci and P. aeruginosa) and at 24 h (P. aeruginosa) among the three groups. Similarly, systemic dissemination of bacteria was not different among the three groups for both pathogens and at both time points. We conclude that SP-B levels in vivo do not influence clearance of bacteria from the lungs.
Akinbi
H T
HT
Division of Pulmonary Biology, Children's Hospital Medical Center, Cincinnati, Ohio 45229-3039, USA.
Bhatt
H
H
Hull
W M
WM
Weaver
T E
TE
D000818:Animals; D008168:Lung / Q000382:microbiology*; D008657:Metabolic Clearance Rate; D051379:Mice; D008822:Mice, Transgenic; D011510:Proteolipids / Q000378:metabolism*; D011550:Pseudomonas aeruginosa / Q000378:metabolism*; D011663:Pulmonary Surfactants / Q000378:metabolism*; D012995:Solubility; D013292:Streptococcus agalactiae / Q000378:metabolism*; D014867:Water / Q000737:chemistry
D011510:Proteolipids; D011663:Pulmonary Surfactants; D014867:Water