Stem-Like Cell Characteristics from Breast Milk of Mothers with Preterm Infants as Compared to Mothers with Term Infants

Purpose: Breast milk stem cells are hypothesized to be involved in infant health and development. Our research team is the first known team to enroll mothers of hospitalized preterm infants during the first few weeks of lactation and compare stem cell phenotypes and gene expression to mothers of healthy full-term infants. Settings: Participants were recruited from a Level IV Neonatal Intensive Care Unit (preterm dyads) and the community (full-term dyads) in the northeastern United States. Participants: Mothers of hospitalized preterm infants (<37 weeks gestational age at birth) and mothers of healthy full-term infants (>39 weeks gestational age at birth). Results: Breast milk stem-like cell populations were identified in both preterm and full-term breast milk samples. The data suggest variability in the proportion of stem cell phenotypes present, as well as statistically significant differential expression (both over- and underexpression) of stem cell-specific genetic markers when comparing mothers' milk for preterm and full-term births. Conclusions: Our findings indicate that (1) stem cells are present in preterm breast milk; (2) differential expression of stem cell-specific markers can be detected in preterm and full-term breast milk samples; and (3) the percentage of cells expressing the various stem cell-specific markers differs when preterm and full-term breast milk samples are compared.