Transmission of Intestinal Bifidobacterium longum subsp. longum Strains from Mother to Infant, Determined by Multilocus Sequencing Typing and Amplified Fragment Length Polymorphism

Abstract

The gastrointestinal tracts of neonates are colonized by bacteria immediately after birth. It has been discussed that the intestinal microbiota of neonates includes strains transferred from the mothers. Although some studies have indicated possible bacterial transfer from the mother to the newborn, this is the first report confirming the transfer of bifidobacteria at the strain level. Here, we investigated the mother-to-infant transmission of Bifidobacterium longum subsp. longum by genotyping bacterial isolates from the feces of mothers before delivery and of their infants after delivery. Two hundred seven isolates from 8 pairs of mothers and infants were discriminated by multilocus sequencing typing (MLST) and amplified fragment length polymorphism (AFLP) analysis. By both methods, 11 strains of B. longum subsp. longum were found to be monophyletic for the feces of the mother and her infant. This finding confirms that these strains were transferred from the intestine of the mother to that of the infant. These strains were found in the first feces (meconium) of the infant and in the feces at days 3, 7, 30, and 90 after birth, indicating that they stably colonize the infant's intestine immediately after birth. The strains isolated from each family did not belong to clusters derived from any of the other families, suggesting that each motherinfant pair might have unique family-specific strains.

Of the bugs that shape us: maternal obesity, the gut microbiome, and long-term disease risk

“…Consistent with this notion, the distinct microbiome signature of the meconium of newborn infants has been shown to be altered by maternal metabolic and health status (73). The presence of specific strains of maternal enteric bacteria in the meconium implies that the fetus is exposed to microbes from the maternal gut in utero (74) and points to the maternal gut as a key player in the development of fetal gut microbiome. Commensal bacteria from the maternal gut have been isolated from umbilical cord blood of healthy neonates born by cesarean section (71) and oral bacteria have been found in the placenta and amniotic fluid (71) in healthy term pregnancies, and likely unrelated to intra-amniotic infection and preterm labor (69,75).…”

Gut microbiota: a source of novel tools to reduce the risk of human disease?

“…Bifidobacterium-dominated microbiota is more frequent in breastfed than among formula-fed infants. The transfer of specific Bifidobacterium strains from mothers to breastfed infants has been reported (47,48), suggesting unique and specific maternal microbial transfer. In parallel, the mode of delivery has also been reported to affect immune development.…”

The Host Genotype and Environment Affect Strain Types of Bifidobacterium longum subsp. longum Inhabiting the Intestinal Tracts of Twins

“…All the samples were kept at 0 to 4°C and delivered to the laboratory within 24 h for subsequent procedures. The anaerobic transport medium (per 1000 ml) contained 0.225 g KH 2 PO 4 , 0.225 g NaCl, 0.225 g (NH 4 ) 2 SO 4 , 0.0225 g CaCl 2 , 0.0225 g MgSO 4 , 0.5 g L-cysteine hydrochloride, 0.001 g resazurin, 0.5 g agar, 10 g Lab Lemco powder, 100 ml glycerol, and 2.1 ml 8% Na 2 CO 3 (11). Five fecal samples were collected from each participant at time zero (time of the first sampling) and at 2, 4, 6, and 8 months thereafter.…”

“…Environment-associated factors include diet, geographical location, and the maternal source in early life (9,10,11,12). A recent study implies that the first bacteria entering the intestine of an infant may be derived from his/her mother's placenta (9).…”