AIMS: Bifidobacteria and lactobacilli are part of the human normal intestinal microbiota and may possibly be transferred to the placenta. It was hypothesized that intestinal bacteria or their components are present in the placenta and that the foetus may be exposed to them. We investigated the presence of bifidobacteria and lactobacilli and their DNA in the human placenta. METHODS AND RESULTS: We studied 34 human placentae (25 vaginal and nine caesarean deliveries) for the presence Bifidobacterium spp. and Lactobacillus rhamnosus. Cultivation was used for the detection of viable cells and genus and species-specific PCR for the detection of DNA. No bifidobacteria or lactobacilli were found by cultivation. Bifidobacterial DNA was detected in 33 and L. rhamnosus DNA in 31 placenta samples. CONCLUSIONS: DNA from intestinal bacteria was found in most placenta samples. The results suggest that horizontal transfer of bacterial DNA from mother to foetus may occur via placenta. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacterial DNA contains unmethylated CpG oligodeoxynucleotide motifs which induce immune effects. Specific CpG motifs activate Toll-like receptor 9 and subsequently trigger Th-1-type immune responses. Although the newborn infant is considered immunologically immature, exposure by bacterial DNA may programme the infant's immune development during foetal life earlier than previously considered.
AIMS: Bifidobacteria and lactobacilli are part of the human normal intestinal microbiota and may possibly be transferred to the placenta. It was hypothesized that intestinal bacteria or their components are present in the placenta and that the foetus may be exposed to them. We investigated the presence of bifidobacteria and lactobacilli and their DNA in the human placenta. METHODS AND RESULTS: We studied 34 human placentae (25 vaginal and nine caesarean deliveries) for the presence Bifidobacterium spp. and Lactobacillus rhamnosus. Cultivation was used for the detection of viable cells and genus and species-specific PCR for the detection of DNA. No bifidobacteria or lactobacilli were found by cultivation. Bifidobacterial DNA was detected in 33 and L. rhamnosus DNA in 31 placenta samples. CONCLUSIONS: DNA from intestinal bacteria was found in most placenta samples. The results suggest that horizontal transfer of bacterial DNA from mother to foetus may occur via placenta. SIGNIFICANCE AND IMPACT OF THE STUDY: Bacterial DNA contains unmethylated CpG oligodeoxynucleotide motifs which induce immune effects. Specific CpG motifs activate Toll-like receptor 9 and subsequently trigger Th-1-type immune responses. Although the newborn infant is considered immunologically immature, exposure by bacterial DNA may programme the infant's immune development during foetal life earlier than previously considered.
Authors: Amanda L Prince; Ryan M Pace; Tyler Dean; Diana Takahashi; Paul Kievit; Jacob E Friedman; Kjersti M Aagaard Journal: Am J Primatol Date: 2019-05-07 Impact factor: 2.371
Authors: Michelle D Rodriguez; Kevin K Yu; Zubin S Paul; Maureen Keller-Wood; Charles E Wood; Eric W Triplett Journal: Appl Environ Microbiol Date: 2019-09-17 Impact factor: 4.792
Authors: Christian Milani; Sabrina Duranti; Francesca Bottacini; Eoghan Casey; Francesca Turroni; Jennifer Mahony; Clara Belzer; Susana Delgado Palacio; Silvia Arboleya Montes; Leonardo Mancabelli; Gabriele Andrea Lugli; Juan Miguel Rodriguez; Lars Bode; Willem de Vos; Miguel Gueimonde; Abelardo Margolles; Douwe van Sinderen; Marco Ventura Journal: Microbiol Mol Biol Rev Date: 2017-11-08 Impact factor: 11.056