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Human Placental and Decidual Organ Cultures to Study Infections at the Maternal-fetal Interface
Published on: July 21, 2016
Bifidobacterium and Lactobacillus DNA in the human placenta
R Satokari1, T Grönroos, K Laitinen
1Functional Foods Forum, University of Turku, Itäinen Pitkäkatu 4A, Turun Yliopisto, Finland. reetta.satokari@utu.fi
Letters in Applied Microbiology
|November 21, 2008
Summary
Bacterial DNA from the gut, including Bifidobacteria and Lactobacilli, was detected in most human placentae. This suggests potential transfer from mother to fetus, possibly influencing infant immune development.
Area of Science:
- Microbiology
- Immunology
- Perinatology
Background:
- Bifidobacteria and lactobacilli are key components of the human gut microbiota.
- These bacteria or their components may be transferable to the placenta.
- The fetus might be exposed to intestinal bacteria during gestation.
Purpose of the Study:
- To investigate the presence of bifidobacteria and lactobacilli, and their DNA, in human placenta samples.
- To determine if intestinal bacteria or their genetic material can be found in the placenta.
Main Methods:
- Analysis of 34 human placenta samples from vaginal and caesarean deliveries.
- Utilized cultivation techniques to detect viable bacterial cells.
- Employed genus and species-specific PCR to detect bacterial DNA.
Main Results:
- No viable bifidobacteria or lactobacilli were detected by cultivation.
- Bifidobacterial DNA was identified in 33 out of 34 placenta samples.
- Lactobacillus rhamnosus DNA was detected in 31 out of 34 placenta samples.
Conclusions:
- Bacterial DNA, specifically from intestinal bacteria, is prevalent in human placenta samples.
- These findings suggest a potential horizontal transfer of bacterial DNA from mother to fetus via the placenta.
- Exposure to bacterial DNA in utero may influence the programming of infant immune development through CpG motifs and Toll-like receptor 9 activation.
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