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A Murine Model of Group B Streptococcus Vaginal Colonization
Published on: November 16, 2016
Naturalization of the microbiota developmental trajectory of Cesarean-born neonates after vaginal seeding
Se Jin Song1, Jincheng Wang2, Cameron Martino3
1Department of Pediatrics, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Center for Microbiome Innovation, University of California, San Diego, La Jolla, CA 92093, USA.
Insights
Restoring maternal vaginal fluids after Cesarean section (CS) birth helps normalize infant gut microbiota development. This study shows CS-born infants receiving vaginal microbial exposure had microbiota trajectories similar to vaginally born infants.
Area of Science:
- Microbiome research
- Immunology
- Pediatric health
Background:
- Early life microbial exposures are critical for immune system development.
- Cesarean section (CS) birth is linked to altered infant microbiota development compared to vaginal birth.
- Perturbations in early microbiota are associated with immune-related disorders.
Purpose of the Study:
- To investigate the long-term effects of restoring maternal vaginal fluid exposure in Cesarean section (CS)-born infants.
- To determine if microbial restoration after CS birth can normalize infant microbiota trajectories.
- To understand the role of maternal vaginal fluids in seeding the infant microbiome.
Main Methods:
- Longitudinal study tracking microbial development in 177 infants over the first year of life.
- 16S rRNA gene sequencing used to analyze microbiota composition across multiple body sites.
- Comparison between vaginally born infants, CS-born infants, and CS-born infants exposed to maternal vaginal fluids via gauze.
Main Results:
- Microbiota trajectories of CS-born infants exposed to maternal vaginal fluids more closely resembled those of vaginally born infants.
- Maternal vaginal microbiomes shared a majority of amplicon sequence variants with other maternal sites.
- Demonstrated long-term naturalization of the microbiota in CS-born infants through early microbial exposure.
Conclusions:
- Early microbial restoration via maternal vaginal fluids may mitigate altered microbiota development in CS-born infants.
- Maternal vaginal fluids possess pluripotential capacity to provide pioneer bacterial colonizers for newborns.
- Further randomized clinical trials are warranted to confirm reduced disease risk and elucidate mechanisms in CS-born infants.
Background:
Early microbiota perturbations are associated with disorders that involve immunological underpinnings. Cesarean section (CS)-born babies show altered microbiota development in relation to babies born vaginally. Here we present the first statistically powered longitudinal study to determine the effect of restoring exposure to maternal vaginal fluids after CS birth.
Methods:
Using 16S rRNA gene sequencing, we followed the microbial trajectories of multiple body sites in 177 babies over the first year of life; 98 were born vaginally, and 79 were born by CS, of whom 30 were swabbed with a maternal vaginal gauze right after birth.
Findings:
Compositional tensor factorization analysis confirmed that microbiota trajectories of exposed CS-born babies aligned more closely with that of vaginally born babies. Interestingly, the majority of amplicon sequence variants from maternal vaginal microbiomes on the day of birth were shared with other maternal sites, in contrast to non-pregnant women from the Human Microbiome Project (HMP) study.
Conclusions:
The results of this observational study prompt urgent randomized clinical trials to test whether microbial restoration reduces the increased disease risk associated with CS birth and the underlying mechanisms. It also provides evidence of the pluripotential nature of maternal vaginal fluids to provide pioneer bacterial colonizers for the newborn body sites. This is the first study showing long-term naturalization of the microbiota of CS-born infants by restoring microbial exposure at birth.
Funding:
C&D, Emch Fund, CIFAR, Chilean CONICYT and SOCHIPE, Norwegian Institute of Public Health, Emerald Foundation, NIH, National Institute of Justice, Janssen.
