Abstract:
:Legionella pneumophila is a gram-negative facultative intracellular parasite of macrophages. Although L. pneumophila is the causative agent of a severe pneumonia known as Legionnaires' disease, it is likely that most infections caused by this organism are cleared by the host innate immune system. It is predicted that host pattern recognition proteins belonging to the Toll-like receptor (TLR) family are involved in the protective innate immune responses. We examined the role of TLR-mediated responses in L. pneumophila detection and clearance using genetically altered mouse hosts in which the macrophages are permissive for L. pneumophila intracellular replication. Our data demonstrate that cytokine production by bone marrow-derived macrophages (BMMs) in response to L. pneumophila infection requires the TLR adapter protein MyD88 and is reduced in the absence of TLR2 but not in the absence of TLR4. Bacterial growth ex vivo in BMMs from MyD88-deficient mice was not enhanced compared to bacterial growth ex vivo in BMMs from heterozygous littermate controls. Wild-type mice were able to clear L. pneumophila from the lung, whereas respiratory infection of MyD88-deficient mice caused death that resulted from robust bacterial replication and dissemination. In contrast to an infection with virulent L. pneumophila, MyD88-deficient mice were able to clear infections with L. pneumophila dotA mutants, indicating that MyD88-independent responses in the lung are sufficient to clear bacteria that are unable to replicate intracellularly. In vivo growth of L. pneumophila was enhanced in the lungs of TLR2-deficient mice, which resulted in a delay in bacterial clearance. No significant differences were observed in the growth and clearance of L. pneumophila in the lungs of TLR4-deficient mice and heterozygous littermate control mice. Our data indicate that MyD88 is crucial for eliciting a protective innate immune response against virulent L. pneumophila and that TLR2 is one of the pattern recognition receptors involved in initiating this MyD88-dependent response.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Archer KA,Roy CRdoi
10.1128/IAI.02049-05subject
Has Abstractpub_date
2006-06-01 00:00:00pages
3325-33issue
6eissn
0019-9567issn
1098-5522pii
74/6/3325journal_volume
74pub_type
杂志文章abstract::Using pharmacologic and biochemical criteria, we evaluated whether uptake of four different Chlamydia trachomatis serovars, D, E, K, and L2, was dependent upon lipid rafts. Our data suggest that lipid raft-mediated entry is not required for C. trachomatis infection of cultured epithelial cells. ...
journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.72.12.7367-7373.2004
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journal_title:Infection and immunity
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doi:10.1128/iai.70.6.2915-2925.2002
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.2.657-661.1992
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.68.2.809-814.2000
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.31.2.767-774.1981
更新日期:1981-02-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.41.2.563-569.1983
更新日期:1983-08-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00519-16
更新日期:2016-11-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.6.1720-1729.1990
更新日期:1990-06-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.1.279-281.1990
更新日期:1990-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
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更新日期:2006-03-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.72.8.4351-4356.2004
更新日期:2004-08-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.62.8.3396-3407.1994
更新日期:1994-08-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.7.4.597-599.1973
更新日期:1973-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.13.3.696-703.1976
更新日期:1976-03-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.59.11.3909-3916.1991
更新日期:1991-11-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.48.3.607-610.1985
更新日期:1985-06-01 00:00:00
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journal_title:Infection and immunity
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.60.2.565-570.1992
更新日期:1992-02-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.27.1.231-234.1980
更新日期:1980-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00846-07
更新日期:2007-12-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.22.3.798-803.1978
更新日期:1978-12-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.61.1.64-70.1993
更新日期:1993-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.36.1.114-122.1982
更新日期:1982-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.58.1.269-271.1990
更新日期:1990-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.15.3.799-806.1977
更新日期:1977-03-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/iai.71.1.309-316.2003
更新日期:2003-01-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.19.3.923-927.1978
更新日期:1978-03-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.00316-16
更新日期:2016-09-19 00:00:00