Our project aims to identify the link between early intestinal microbiota signatures in very preterm neonates and the maturation of gut, lung, and the development of immunity which is unbalanced in several diseases such as allergy. This will be assessed using gnotobiotic mice: newborn germ-free mice, colonized by different fecal microbiotas representative of the various bacterial patterns identified in very premature infants through EPIFLORE study (ANR12-BSV3-0025). Following this primary colonization, these microbiotas will be allowed to diversify over time (Figure 1).
During this 2-year project, first, we plan to study the impact of the first-month microbiota on the maturation of the gut and lung ecosystems and immunity over time until adulthood (i.e. 6 weeks) at local and systemic level. Second, we will study the impact of the first-month microbiota colonization on allergies development). These data will be essential to further study the impact of probiotics/prebiotics during primary colonization to prevent long-term outcomes.
The first year was devoted to WP1 : Impact of preterm colonization on gut-lung maturation and immunity with two aims: (1) To characterize the maturation of gut, lung, and immunity in presence of M3 or M5; (2) To evaluate the resilience (or not) of M3 and M5 after the weaning diversification and its impact. Weaning has a major impact on immunity development, in relation with the microbiota. This is the first study on the capacity of diversification at weaning to correct the effects of early dysbiosis.