Transmission of maternal oral pathobionts to the infant gut predisposes offspring to exacerbated enteritis.

Infants acquire maternal microbes from various body sites, which become early colonizers of the infant gut. Consequently, disruption of healthy maternal microbiota, particularly maternal gut dysbiosis, can influence the composition of offspring's gut microbiota and affect their health outcomes. However, the effects of non-gut maternal microbes on infant health and disease remain largely unexplored. Here, we demonstrate that maternal oral dysbiosis can have lasting health impacts on offspring. Ligature-induced periodontitis in mothers promotes the expansion of oral pathobionts, including Klebsiella aerogenes, which are transmitted to the infant gut, altering intestinal immunity and rendering offspring more susceptible to T cell-dependent enteritis. Notably, although these maternal oral pathobionts are eradicated as the microbiota matures, the imprinted susceptibility to enteritis persists into adulthood. Thus, maternal oral dysbiosis not only alters the early gut microbiota of infants but also may have long-term health implications for offspring.