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

Study Overview
=================
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.

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

Conditions
-----------------
Healthy

Intervention / Treatment
-----------------
* Diagnostic Test: nasal swab


Participation Criteria
=================
Eligibility Criteria
-----------------
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

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Healthy volunteers<br>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 | Diagnostic Test: nasal swab<br>* nasal swab will be performed to analysis biological markers at every visit.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| level of ICAM-1 expression in nasal cells | Compare the level of ICAM-1 expression in nasal cells with and without the presence of intracellular Staphylococcus aureus | Months: 0 | 

Secondary Outcome Measures

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

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Staphylococcus aureus, ICAM-1, nasal cells, S. aureus, nasal swab