Eosinophils Orchestrate Intestinal Remodeling and Promote Innate Defense During Reproduction

This adaptation culminates during lactation, limits pathogen entry and dissemination, conferring broad innate protection against enteric bacterial infections. Remarkably, both eosinophil accumulation and goblet cell induction persist after lactation, revealing durable remodeling of the intestinal immune and epithelial landscapes with sustained innate defense. Our findings demonstrate that, despite a general trend toward systemic immunosuppression during reproduction, the maternal intestine undergoes remodeling to strengthen innate defense against enteric pathogens, a mechanism that may have evolved to protect mothers and offspring in pathogen-rich environments.

More broadly, our work establishes a framework for studying tissue immune adaptation across the reproductive cycle and highlights that tissue can retain memory of physiological states, with lasting implications for host defense and reproductive health.