Abstract:
:Current approaches used for dose-response modeling of low-dose exposures of pathogens rely on assumptions and extrapolations. These models are important for quantitative microbial risk assessment of food. A mechanistic framework has been advocated as an alternative approach for evaluating dose-response relationships. The objectives of this study were to investigate the invasion behavior of Campylobacter jejuni, which could arise as a foodborne illness even if there are low counts of pathogens, into Caco-2 cells as a model of intestinal cells and to develop a mathematical model for invading cell counts to reveal a part of the infection dose-response mechanism. Monolayer-cultured Caco-2 cells and various concentrations of C. jejuni in culture were cocultured for up to 12 h. The numbers of C. jejuni bacteria invading Caco-2 cells were determined after coculture for different time periods. There appeared to be a maximum limit to the invading bacterial counts, which showed an asymptotic exponential increase. The invading bacterial counts were higher with higher exposure concentrations (maximum, 5.0 log CFU/cm2) than with lower exposure concentrations (minimum, 0.6 log CFU/cm2). In contrast, the ratio of invading bacteria (number of invading bacteria divided by the total number of bacteria exposed) showed a similar trend regardless of the exposure concentration. Invasion of C. jejuni into intestinal cells was successfully demonstrated and described by the developed differential equation model with Bayesian inference. The model accuracy showed that the 99% prediction band covered more than 97% of the observed values. These findings provide important information on mechanistic pathogen dose-response relationships and an alternative approach for dose-response modeling.IMPORTANCE One of the infection processes of C. jejuni, the invasion behavior of the bacteria in intestinal epithelial cells, was revealed, and a mathematical model for prediction of the cell-invading pathogen counts was developed for the purpose of providing part of a dose-response model for C. jejuni based on the infection mechanism. The developed predictive model showed a high accuracy of more than 97% and successfully described the C. jejuni invading counts. The bacterial invasion predictive model of this study will be essential for the development of a dose-response model for C. jejuni based on the infection mechanism.
journal_name
Appl Environ Microbioljournal_title
Applied and environmental microbiologyauthors
Abe H,Koyama K,Koseki Sdoi
10.1128/AEM.01551-20subject
Has Abstractpub_date
2020-12-17 00:00:00issue
1eissn
0099-2240issn
1098-5336pii
AEM.01551-20journal_volume
87pub_type
杂志文章abstract::Feeding of bovine milk to mice induced a high incidence of bacterial translocation from the intestines to the mesenteric lymph nodes, and the bacteria involved were mainly members of the family Enterobacteriaceae. Supplementation of the milk diet with bovine lactoferrin or a pepsin-generated hydrolysate of bovine lact...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.61.11.4131-4134.1995
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doi:10.1128/AEM.64.6.2096-2104.1998
更新日期:1998-06-01 00:00:00
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journal_title:Applied and environmental microbiology
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doi:
更新日期:1996-02-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.62.5.1723-1727.1996
更新日期:1996-05-01 00:00:00
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pub_type: 杂志文章
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更新日期:1986-07-01 00:00:00
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pub_type: 杂志文章
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更新日期:2012-04-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.67.1.307-316.2001
更新日期:2001-01-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.41.5.1192-1201.1981
更新日期:1981-05-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
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更新日期:2014-01-01 00:00:00
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更新日期:2003-02-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
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更新日期:2008-09-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.01955-09
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
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doi:10.1128/AEM.60.6.2137-2146.1994
更新日期:1994-06-01 00:00:00
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journal_title:Applied and environmental microbiology
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更新日期:1978-08-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.65.6.2478-2484.1999
更新日期:1999-06-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/aem.69.7.4200-4204.2003
更新日期:2003-07-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.61.5.2061-2065.1995
更新日期:1995-05-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.37.5.886-891.1979
更新日期:1979-05-01 00:00:00
abstract::Two activities involved in terminal pathway conversion of sterigmatocystin to aflatoxin B1 were isolated from an aflatoxin-nonproducing mutant of Aspergillus parasiticus (avn-1), and the time course of appearance of the activities in culture was determined. Subcellular fractionation of fungal mycelia resolved the two ...
journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.53.7.1711-1713.1987
更新日期:1987-07-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.02127-07
更新日期:2008-03-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/aem.70.3.1405-1412.2004
更新日期:2004-03-01 00:00:00
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journal_title:Applied and environmental microbiology
pub_type: 杂志文章
doi:10.1128/AEM.71.6.3276-3284.2005
更新日期:2005-06-01 00:00:00