Cytokines, Chemokines, and Growth Factors in Banked Human Donor Milk for Preterm Infants

Background: There has been a recent increase in availability of banked donor milk for feeding of preterm infants. This milk is pooled from donations to milk banks from carefully screened lactating women. The milk is then pasteurized by the Holder method to remove all microbes. The processed milk is frozen, banked, and sold to neonatal intensive care units (NICUs). The nutrient bioavailability of banked donor milk has been described, but little is known about preservation of immune components such as cytokines, chemokines, and growth factors (CCGF). Objective: The objective was to compare CCGF in banked donor milk with mother's own milk (MOM). Methods: Aliquots (0.5 mL) were collected daily from MOM pumped by 45 mothers of NICU-admitted infants weighing < 1500 grams at birth. All daily aliquots of each mother's milk were pooled each week during 6 weeks of an infant's NICU stay or for as long as the mother provided MOM. The weekly pooled milk was measured for a panel of CCGF through multiplexing using magnetic beads and a MAGPIX instrument. Banked donor milk samples (n = 25) were handled and measured in the same way as MOM. Results: Multiplex analysis revealed that there were levels of CCGF in banked donor milk samples comparable to values obtained from MOM after 6 weeks of lactation. Conclusion: These data suggest that many important CCGF are not destroyed by Holder pasteurization.