Mother-to-Infant Transfer of Microbiomes: Mechanisms, Impact, and Immunological Consequences

Early-life microbial colonization represents one of the most critical determinants of human development. Although the neonatal period was once considered biologically “sterile,” emerging evidence highlights a dynamic and multifactorial process in which microbial communities are transferred from mother to infant. Mode of delivery, breastfeeding, maternal diet, environmental exposures, and early-life antibiotic use collectively shape the establishment of the infant microbiota. These initial microbial encounters influence immune maturation, mucosal barrier formation, immune memory establishment, and metabolic programming. However, substantial gaps remain in elucidating the causal mechanisms that govern microbial transmission and in understanding how maternal physiology, lifestyle, and immunological status collectively affect microbial inheritance during the perinatal period.This Research Topic aims to address the fundamental question of how maternal–infant microbial transfer occurs and to clarify its broader biological significance across both human and animal systems. A deeper mechanistic understanding will help resolve current controversies, including the extent of in utero microbial exposure, the long-term influence of mode of delivery on microbial assembly, and the pathways through which early microbial interactions shape innate and adaptive immunity, including the establishment of immune memory. We welcome studies that generate mechanistic insights, apply multi-omics approaches, employ advanced experimental models, and/or use mathematical modeling to understand infant microbiome establishment dynamics and host–microbiome interactions. By bringing together diverse expertise, this collection seeks to foster conceptual advances and stimulate new strategies that leverage maternal and early-life microbial interactions to support healthy immunological development.Relevant topics include neonatal and early childhood immune maturation, the impacts of maternal diet, probiotics, prebiotics, and antibiotic exposure, maternal infection, inflammation, vaccination, or immune status as determinants of microbial inheritance, and microbial seeding associated with delivery and breastfeeding. Studies examining host genetic factors, mucosal barrier properties, microbial metabolites, environmental influences, and computational approaches to early microbiome assembly are also encouraged.Submissions may include original research or comprehensive reviews that deepen our understanding of the mechanisms underlying mother-to-infant microbial transmission in humans and/or animal models.We welcome articles addressing, but not limited to, the following themes:-Mechanisms of maternal–infant microbial transfer during pregnancy, delivery, and the early postnatal period (humans and animals)-Contributions of mode of delivery (vaginal birth, cesarean section, assisted delivery) to initial microbial seeding and long-term microbiota trajectories-Microbial signatures and potential routes of in utero exposure, including placental, amniotic, and fetal tissues-Impacts of breastfeeding, human milk composition, and donor milk or formula on microbial colonization and immune maturation-Influence of maternal diet, nutrition, and metabolic status on maternal and infant microbiomes-Effects of maternal and early-life exposure to antibiotics, probiotics, prebiotics, and synbiotics on microbial inheritance and immune development-Roles of maternal infection, inflammation, vaccination, and immune status in shaping infant microbial colonization and function-Neonatal and early-life innate and adaptive immune responses to the microbiome, including mechanisms of immune education and immune memory establishment-Host genetic determinants and mucosal barrier properties governing early-life microbial assembly-Functional consequences of early microbial colonization for immune education, mucosal barrier formation, and metabolic programming-Microbial metabolites and host–microbe signaling pathways involved in neonatal and early childhood immune maturation-Environmental influences (e.g., household, siblings, pets, hospital vs. home birth, geography) on early microbiota establishment-Application of multi-omics (metagenomics, metatranscriptomics, metabolomics, proteomics) to dissect mother–infant microbial transmission-Use of advanced experimental models (e.g., gnotobiotic animals, organoids, in vitro co-culture systems) to uncover causal mechanisms-Mathematical and computational modeling to understand infant microbiome establishment dynamics and host–microbiome interactions-Longitudinal cohort studies linking early-life microbial patterns with later immune, metabolic, or neurodevelopmental outcomes (humans and animals)-Interventional strategies that leverage maternal or early-life microbial modulation to promote healthy immunological development Topic editors: Daisuke NAGAKUBO, Mako Kawai, Claudia Matteucci Source: https://www.frontiersin.org/research-topics/76226/mother-to-infant-transfer-of-microbiomes-mechanisms-impact-and-immunological-consequences