NCT03596827

The Protective Immune Response to Attenuated Enterotoxigenic Escherichia Coli Infection

The Protective Immune Response to Attenuated Enterotoxigenic Escherichia Coli Infection in Healthy Human Subjects: A Pilot Study

• Status: Completed
• Phase: N/A
• Study type: Interventional
• Enrollment: 30 (actual)
• Sponsor: NIZO Food Research · Academic / Other
• Sex: Male
• Age: 18 Years – 55 Years
• Healthy volunteers: Accepted

Summary

The existing diarrhoeagenic Escherichia coli (E. coli) challenge model is already suitable for dietary interventions in its current form, targeted to impact on the immediate clinical symptoms upon E. coli infection. In order to make the model also suitable for dietary interventions that are aimed at support of the protective response against reinfection, the immune response triggered by the primary infection should be suboptimal. The MIRRE pilot study is set up to determine how much the primary inoculation dose of diarrheagenic E. coli should be lowered in order to result in a reduced protective response upon a secondary infection.

Detailed description

The MIRRE pilot study is a randomized, double-blind dose-response, parallel 7 weeks human infection study. Healthy male subjects, 18-55 years of age who fulfil all of the inclusion criteria and none of the exclusion criteria, will be randomly assigned to one of five inoculation dosages of a live attenuated diarrheagenic E. coli strain (n=6 per group). Subjects will be instructed to maintain their usual pattern of physical activity and their habitual food intake, but to reduce and standardize their dietary calcium intake. After a standardized evening meal and an overnight fast, subjects will be orally infected on day 14 and 35 with a live, but attenuated, diarrheagenic E. coli (strain E1392/75-2A; collection NIZO food research). Five groups of 6 subjects will be provided one of the following dosages at day 14: 1E10 CFU (standard dose); 1E9 CFU; 1E8 CFU; 1E7 CFU or 1E6 CFU of the E.coli strain. At study day 35, all subjects will receive a second inoculation of 1E10 CFU of the E.coli strain. At various time points before and after diarrheagenic E. coli challenges an online diary will be kept to record information on stool consistency, frequency and severity of symptoms, and blood and stool samples are collected to quantify antibody levels and to quantify fecal infection parameters. The hypothesis of this pilot study is that the E. coli infection dose at primary inoculation determines the outcomes of the protective immune response and the extent of clinical symptoms at a secondary inoculation.Therefore the CFA/II-specific IgG antibody response, in relation to clinical symptoms, is the main outcome.

Conditions

• Diarrhea

Interventions

Type	Name	Description
BIOLOGICAL	E. coli strain E1392-75-2A dose 1E10 CFU	Diarrhoeagenic E. coli strain E1392/75-2A serotype O6:H16 belongs to Pathogen class 2 . The strain has a deletion of genes encoding the heat-labile (LT) and heat-stable (ST) toxins and can not produce any toxins. However, it continues to express Colonization Factor Antigen II (CFA/II) and provides 75% protection against challenge with an LT, ST, CFA/II strain
BIOLOGICAL	E. coli strain E1392-75-2A dose 1E9 CFU	Diarrhoeagenic E. coli strain E1392/75-2A serotype O6:H16 belongs to Pathogen class 2 . The strain has a deletion of genes encoding the heat-labile (LT) and heat-stable (ST) toxins and can not produce any toxins. However, it continues to express Colonization Factor Antigen II (CFA/II) and provides 75% protection against challenge with an LT, ST, CFA/II strain
BIOLOGICAL	E. coli strain E1392-75-2A dose 1E8 CFU	Diarrhoeagenic E. coli strain E1392/75-2A serotype O6:H16 belongs to Pathogen class 2 . The strain has a deletion of genes encoding the heat-labile (LT) and heat-stable (ST) toxins and can not produce any toxins. However, it continues to express Colonization Factor Antigen II (CFA/II) and provides 75% protection against challenge with an LT, ST, CFA/II strain
BIOLOGICAL	E. coli strain E1392-75-2A dose 1E7 CFU	Diarrhoeagenic E. coli strain E1392/75-2A serotype O6:H16 belongs to Pathogen class 2 . The strain has a deletion of genes encoding the heat-labile (LT) and heat-stable (ST) toxins and can not produce any toxins. However, it continues to express Colonizat
BIOLOGICAL	E. coli strain E1392-75-2A dose 1E6 CFU	Diarrhoeagenic E. coli strain E1392/75-2A serotype O6:H16 belongs to Pathogen class 2 . The strain has a deletion of genes encoding the heat-labile (LT) and heat-stable (ST) toxins and can not produce any toxins. However, it continues to express Colonizat

Timeline

• Start date: 2018-09-26
• Primary completion: 2018-11-13
• Completion: 2019-02-28
• First posted: 2018-07-24
• Last updated: 2019-03-20

Locations

1 site across 1 country: Netherlands