Maternal immune regulation of lactogenesis

Abstract Breastfeeding has long been associated with health benefits for the infant. Breast milk is composed of essential nutrients and bioactive molecules shaping growth, immune development offspring. An optimal mammary gland (MG) during pregnancy critical to maintaining beneficial effects lactation. Nevertheless, how lactation process regulated by system remains largely unexplored. Our data reveal that commitment epithelial cells into milk-secreting accumulation T-bet +lymphoid cells, preferentially localized at proximity inside epithelium. Among +cells, we characterized an unconventional T cell population exhibiting common features gut CD8αα +intra-epithelial lymphocytes deriving from same thymic progenitor. Such thymus involution specific enrichment in precursor migrates MG pregnancy. These promote production expression β-casein, one main protein, resulting increase newborn weight. This work uncovers a previously unappreciated contribution adaptive Decoding regulation will allow understand profound transformation this compartment as primary nutritional source offspring may dysregulation could affect long-term newborns. was supported part intramural funds NIAID, NIH.