CD14 is an essential mediator of LPS-induced airway disease.
Chronic lipopolysaccharide (LPS) inhalation in rodents recapitulates many classic features of chronic obstructive pulmonary disease seen in humans, including airways hyperresponsiveness, neutrophilic inflammation, cytokine production in the lung, and small airways remodeling. CD14-deficient mice (C57BL/6(CD14-/-)) have an altered response to systemic LPS, and yet the role of CD14 in the response to inhaled LPS has not been defined. We observed that C57BL/6(CD14-/-) mice demonstrate no discernable physiological or inflammatory response to a single LPS inhalation challenge. However, the physiological (airways hyperresponsiveness) and inflammatory (presence of neutrophils and TNF-alpha in whole lung lavage fluid) responsiveness to inhaled LPS in C57BL/6(CD14-/-) mice was restored by instilling soluble CD14 intratracheally. Intratracheal instillation of wild-type macrophages into C57BL/6(CD14-/-) mice restored neutrophilic inflammation only and failed to restore airways hyperresponsiveness or TNF-alpha protein in whole lung lavage. These findings demonstrate that CD14 is critical to LPS-induced airway disease and that macrophage CD14 is sufficient to initiate neutrophil recruitment into the airways but that CD14 may need to interact with other cell types as well for the development of airways hyperresponsiveness and for cytokine production.
Brass
David M
DM
National Institute of Environmental Health Sciences, Rall Bldg., Rm. C224, PO Box 12233 MD C2-15, 111 Alexander Dr., Research Triangle Park, NC 27709, USA. brassd@niehs.nih.gov
Hollingsworth
John W
JW
McElvania-Tekippe
Erin
E
Garantziotis
Stavros
S
Hossain
Imtaz
I
Schwartz
David A
DA
D000280:Administration, Inhalation; D019264:Adoptive Transfer; D000818:Animals; D016535:Bronchial Hyperreactivity / Q000473:pathology; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry; D004797:Enzyme-Linked Immunosorbent Assay; D007249:Inflammation; D018950:Lipopolysaccharide Receptors / Q000378:metabolism*; D008070:Lipopolysaccharides / Q000008:administration & dosage / Q000494:pharmacology*; D016676:Macrophages, Alveolar / Q000276:immunology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009504:Neutrophils / Q000276:immunology; D012140:Respiratory Tract Diseases / Q000139:chemically induced / Q000473:pathology*; D012995:Solubility; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
D018950:Lipopolysaccharide Receptors; D008070:Lipopolysaccharides; D014409:Tumor Necrosis Factor-alpha