Abstract:
:Nasopharyngeal colonization is a necessary first step in the pathogenesis of Streptococcus pneumoniae. Using isolates containing defined mutations in the S. pneumoniae capsule locus, we found that expression of the capsular polysaccharide is essential for colonization by the type 2 strain D39 and the type 3 strains A66 and WU2. Nonencapsulated derivatives of each of these strains were unable to colonize BALB/cByJ mice. Similarly, type 3 mutants that produced < 6% of the parental amounts of capsule could not colonize. Capsule production equivalent to that of the parent strain was not required for efficient colonization, however, as type 3 mutants producing approximately 20% of the parental amounts of capsule colonized as effectively as the parent. This 80% reduction in capsule level had only a minimal effect on intraperitoneal virulence but caused a significant reduction in virulence via the intravenous route. In the X-linked immunodeficient CBA/N mouse, the type 3 mutant producing ~20% of the parental amount of capsule (AM188) was diminished in its ability to cause invasive disease and death following intranasal inoculation. Following intravenous or intraperitoneal challenge, however, only extended survival times were observed. Our results demonstrate an additional role for capsule in the pathogenesis of S. pneumoniae and show that isolates producing reduced levels of capsule can remain highly virulent.
journal_name
Infect Immunjournal_title
Infection and immunityauthors
Magee AD,Yother Jdoi
10.1128/IAI.69.6.3755-3761.2001keywords:
subject
Has Abstractpub_date
2001-06-01 00:00:00pages
3755-61issue
6eissn
0019-9567issn
1098-5522journal_volume
69pub_type
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更新日期:1992-12-01 00:00:00
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journal_title:Infection and immunity
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journal_title:Infection and immunity
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journal_title:Infection and immunity
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更新日期:1986-04-01 00:00:00
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pub_type: 杂志文章
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更新日期:2005-05-01 00:00:00
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pub_type: 杂志文章
doi:10.1128/iai.68.1.72-79.2000
更新日期:2000-01-01 00:00:00
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journal_title:Infection and immunity
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doi:10.1128/IAI.22.3.842-851.1978
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:
更新日期:1980-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.66.6.2938-2942.1998
更新日期:1998-06-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.55.5.1051-1057.1987
更新日期:1987-05-01 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:1979-01-01 00:00:00
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更新日期:1993-11-01 00:00:00
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pub_type: 杂志文章
doi:10.1128/IAI.57.3.805-809.1989
更新日期:1989-03-01 00:00:00
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journal_title:Infection and immunity
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更新日期:1998-12-01 00:00:00
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更新日期:2001-04-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章,评审
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更新日期:2017-04-21 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.37.3.1270-1277.1982
更新日期:1982-09-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.27.3.837-841.1980
更新日期:1980-03-01 00:00:00
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journal_title:Infection and immunity
pub_type: 杂志文章
doi:10.1128/IAI.69.8.5088-5097.2001
更新日期:2001-08-01 00:00:00