Network modelling links Veillonella to regulatory T cell expansion whilst skin-associated bacteria enhance T cell proliferation in breastfed neonates
Finally, we undertook an integrative analysis of the combined data from flow cytometry, MLR and microbiome sequencing of neonates at 3 weeks of age. Network modelling revealed a range of positive and negative correlations between these parameters. In breastfed neonates CD4+ and CD8+ proliferative responses against maternal antigen were strongly correlated with Gemella and skin-associated taxa (Figure 7a). The presence of Veillonella within the microbiome correlated with the prevalence of Tregs at 3 weeks and this effect was independent of nutrition history (Figure 7b). In breastfed neonates Veillonellawas also associated with HLA-DR expression on CD4+ cells and IFN-γ production in CD8+ cells. These findings suggest that Veillonellamay act to enhance regulatory responses in the early period of life whereas skin-associated bacteria, potentially acquired through breastfeeding, may act to promote proliferative responses.