Inflammation, Intracellular Invasion and Colonization of the Nasal Mucosa by Staphylococcus Aureus

Not Applicable

Completed

• Conditions: Healthy
• Interventions: Diagnostic Test: nasal swab

• Registration Number: NCT04469348
• Lead Sponsor: Centre Hospitalier Universitaire de Saint Etienne

Brief Summary

An inflammatory state of the nasal cells (very close to keratinocytes) could favour the internalization of Staphylococcus aureus and thus constitute a persistent reservoir for the carriage of this bacterium.

Staphylococcus aureus is a commensal bacterium of the skin and mucous membranes that colonizes approximately 2 billion people worldwide Staphylococcus aureus is also a leading cause of community and healthcare-associated infection. Staphylococcus aureus has demonstrated its ability to invade many non-professional phagocytic cell lines such as keratinocytes, osteoblasts, fibroblasts, epithelial cells and endothelial cells. During pro-inflammatory stimulation, internalization of Staphylococcus aureus into keratinocytes is mainly mediated by ICAM-1. These results suggest that, in humans, an inflammatory state of the nasal cells (very close to keratinocytes) could promote the internalization of Staphylococcus aureus and thus constitute a persistent reservoir for the carriage of this bacterium.

Detailed Description

The main objective is to compare the expression level of ICAM-1 in nasal cells with and without the presence of Staphylococcus aureus.

Study Timeline

• Study First Submitted: 2020-07-09
• Study First Submitted QC: 2020-07-13
• Study First Posted: 2020-07-14
• Study Start: 2021-10-18
• Primary Completion: 2023-01-09
• Study Completion: 2023-01-09
• Status Verified: 2024-05
• Last Update Submitted: 2024-05-22
• Last Update Posted: 2024-05-23

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 157

Inclusion Criteria

• Subject affiliated to a social security scheme or entitled person
• Subject who received informed information about the study et signed consent
• Adult subject (≥18ans)
• Healthy Volunteer

Exclusion Criteria

• Subject undergoing antibiotic treatment or having received antibiotic treatment (oral, IV or local) in the month prior to inclusion
• Subject with a major haemostasis disorder or anticoagulant treatment contraindicated for surgery
• Subject with a pathology increasing the nasal carriage of S. aureus (chronic furunculosis, diabetes, HIV infection, chronic rhinosinusitis)
• Subject under guardianship or trusteeship
• Pregnant woman

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Healthy volunteers	nasal swab	Healthy volunteers will be included. They will have nasal swab at the inclusion visit to detect contamination of S. Aureus. * If contamination of S. Aureus: they will have 12 follow-up visits (1 per month) * If no contamination of S. Aureus: their participation stops

Primary Outcome Measures

Name	Time	Method
level of ICAM-1 expression in nasal cells	Months: 0	Compare the level of ICAM-1 expression in nasal cells with and without the presence of intracellular Staphylococcus aureus

Secondary Outcome Measures

Name	Time	Method
concentration of ICAM-1 in S. Aureus	Months: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12	Measure by analysis of nasal swab.
Measurement of the expression of the genes (mRNA dosage) involved in IL-1 beta secretion	Months: 0	Measure by rt-qPCR technique.
Measurement of the expression of the genes (mRNA dosage) involved in activation of autophagy	Months: 0	Measure by rt-qPCR technique.
cytokine concentration	Months: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12	Measure by analysis of nasal swab.

Trial Locations

Locations (1)

CHU de Saint-Etienne; 🇫🇷 Saint-Étienne, France