New research published in Nature Communications suggests that antibodies transferred from mother to child before birth and through breastfeeding may shape the oral immune system in ways that persist into adulthood and reduce susceptibility to periodontitis. The study, led by Professor Avi-Hai Hovav and DMD/PhD student Reem Naamneh at the Hebrew University of Jerusalem Faculty of Dental Medicine, used laboratory mouse models to examine how maternal immunoglobulin G (IgG) antibodies operate beyond providing short-term protection in infancy.

Two distinct pathways of immune transfer

Antibodies transferred during pregnancy reach neonatal salivary glands and are secreted into saliva, where they establish immune tolerance and help the developing immune system distinguish between harmless bacteria and genuine threats. Mice lacking these prenatal antibodies showed heightened immune cell activation, higher bacterial loads in salivary glands and gums, and significantly increased susceptibility to periodontitis in adulthood. Breast milk antibodies served a separate function: supporting the physical development of the oral epithelium and maintaining mucosal barrier integrity. When these antibodies were absent or disrupted by antibiotic exposure, that barrier weakened.

Targeted protection and future prevention strategies

The researchers identified that maternal IgG specifically targets bacteria from the Pasteurellaceae family, pathobionts linked to aggressive forms of periodontitis. This suggests a degree of targeted protection passed from mother to child. The team proposes that these findings could support future preventive strategies, including maternal immunisation during pregnancy, which might enhance specific antibodies passed to offspring and reduce their risk of chronic oral infection later in life. The authors note that further research in human populations will be needed before clinical conclusions can be drawn, as the current findings are based on mouse models.