Influence of Intestinal Microbiota Implantation in Preterm Infants on Microbiota and Immune Orientation at 3 Years

Study Overview
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Brief Summary
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The main objective of this research is to study the links between changes in the intestinal microbiota (in terms of diversity) during the first 6 weeks of life for preterm infants and the presence / absence of a TH1 immune status at 36 months of age.

Detailed Description
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The secondary objectives are to study the links between changes of the intestinal microbiota premature infants in terms of: changing diversity of the microbiota in the first 6 weeks of life; changes in the bacterial community (UniFrac study) during the first 6 weeks of life; diversity of the microbiota up to 6 weeks; -AND- diversity of the microbiota at 1, 2 & 3 years; bacterial communities (UniFrac study) at 1, 2 & 3 years; lymphocyte subpopulation profiles at 3 years; serum immunoglobulin A, G, M, E levels at 3 years; history of infectious episodes, allergic and inflammatory episodes during the first 3 years of life. The links between certain variables known in the literature and neonatal microbiota will be confirmed / studied in our population: mode of delivery; length (and type) of antibiotic therapy in the neonatal period; duration of breastfeeding.

Official Title
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Influence of Intestinal Microbiota Implantation Parameters in the Neonatal Period in Premature Infants on Microbiota Profiles and Immune Orientation at 3 Years of Age

Conditions
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Infant, Premature

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: The parents of the patient (or legal guardian if any) have been informed about the implementation of the study, its objectives, its constraints, and patient rights The parents of the patient (or legal guardian if any) must have given their free and informed consent and signed the consent form The patient must be affiliated with or beneficiary of a health insurance plan Premature infants born at less than 33 weeks of gestation Exclusion Criteria: The patient is participating in another interventional study (Excepted  Recherche du Portage de Clostridium butyricum et de Toxines de Clostridium chez les Prématurés Hospitalisés en Néonatologie afin de prédire la survenue d'Entérocolites Nécrosantes, RCB 2016-A00-529-42 ;  BetaDose Dose reduction of antenatal betamethasone given to prevent the neonatal complications associated with very preterm birth , RCB 2016-001486-90. It is not possible to correctly inform the parent (or legal guardian, if applicable) A serious deformity or digestive malformation was diagnosed at birth During the hospital stay in the neonatology department, the patient had a digestive disease requiring surgery (except necrotizing enterocolitis) A transfer to another hospital is foreseen/predictable (eg, due to geographical distance)

Ages Eligible for Study
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Maximum Age: 1 Day

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| The study population<br>The study population corresponds to infants born at less than 33 weeks of gestation. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The presence/absence of a Th1 type immune orientation | Immune orientation will be determined according to the following ratio determined by lymphocyte stimulation tests: INF-gamma/(INF-gamma+IL+4). The latter ratio varies between 0 and 0.5 with IL-4 > INF-gamma (TH2 orientation) and between 0.5 and 1 when INF-gamma > IL-4 (TH1 orientation). | 36 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Blood lymphocyte subset determination | Subsets are determined according to the presence/absence of the following differentiation clusters: CD3, CD4, CD8, CD19, CD25, CD56, CD127, FOXP3. | 36 months |