Introduction
There is increasing support for a link between early childhood microbiome composition and later development of asthma and atopy [1]. One possible mechanism for this association is the connection between the maternal and infant gut microbiome or “seeding” of the infant microbiome by a mother with asthma or atopy.
Objectives
We investigated whether the maternal gut microbiome in early pregnancy differs between women with and without asthma.
Methods
Faecal samples were collected at 16 weeks gestation (baseline) from women enrolled in SPRING (Study of PRobiotics IN Gestational diabetes), NHMRC funded trial supplementing overweight or obese women with probiotics from 16 weeks through pregnancy [2]. Ten women with asthma and 15 matched controls had DNA isolated from stool samples sequenced by 16S rRNA sequencing and analysed with the QIIME software suite. Samples were ordinated by principal component analysis (PCA). Taxa associated with asthma and healthy controls were identified using the linear discriminant analysis (LDA) effect size method.
Results
Preliminary analysis showed differences in the microbiome between the two groups. Women with asthma had decreased Bifidobacterium longum and increased Ruminococcus callidus abundance compared to women without asthma.
Conclusions
Lower levels of Bifidobacterum longum have been reported in children with allergy [3]. In mice, feeding with Bifidobacterium longum reduced airway inflammation [4]. Bifidobacterium species are thought to influence the host immune system.
A difference can be seen in gut microbiome composition in women with and without asthma in a cohort of overweight and obese women in early pregnancy. These initial findings suggest that mothers with asthma have an altered gut microbiome, similar to that seen in studies of infants who later develop asthma and atopy. It is possible that the infants of women with asthma in pregnancy are inheriting a microbiome already primed for asthma and atopy development. This requires further exploration.