Fig. 1

Transfer of dairy milk exosomes to the human milk consumer. Genetic dairy cow selection enhances mammary epithelial cell miR-148a expression, a crucial epigenetic mechanism enhancing milk yield that potentially also increases milk exosome miR-148a content. Persistent pregnancy of dairy cows further promotes estrogen-stimulated expression of miR-148a and miR-21. Milk exosomes also contain miR-155 and transforming growth factor-β (TGF-β), which promotes the expression of miR-155. Pasteurization has no significant effect on milk exosome integrity and exosomal miR bioavailability. Large scale pasteurization and cooling technology promoted the persistent entry of dairy milk exosomes and their miRs into the human food chain