Send to

Choose Destination
J Infect Dis. 2002 Aug 15;186(4):570-3. Epub 2002 Jul 24.

Toll-like receptor 4 is not involved in host defense against pulmonary Legionella pneumophila infection in a mouse model.

Author information

Department of Infectious Diseases, Tropical Medicine, and AIDS, Academic Medical Center, University of Amsterdam, The Netherlands.


Legionella pneumophila is a gram-negative microorganism that causes a severe pneumonia known as "legionnaires disease." Toll-like receptor 4 (TLR4) transduces the lipopolysaccharide signal and is therefore considered to play a role in host defense against gram-negative bacterial infection. To determine the role of TLR4 in L. pneumophila pneumonia, C3H/HeJ mice, which display a nonfunctional gene encoding TLR4 (TLR4), and wild-type (wt) C3H/HeN mice were intranasally inoculated with L. pneumophila serogroup 1. Infection proceeded in an identical way in TLR4 mutant and wt mice, as reflected by similar bacterial outgrowth in the lungs. In addition, the inflammatory responses to L. pneumophila infection-as assessed by histopathologic analysis, cell influx in bronchoalveolar lavage fluid, myeloperoxidase activity in lungs, and lung cytokine concentrations-were indistinguishable in TLR4 mutant and wt mice. These data suggest that, in this mouse model, TLR4 does not play a role in resistance to L. pneumophila.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Silverchair Information Systems
Loading ...
Support Center