Comparisons of proteomic profiles of whey protein between donor human milk collected earlier than 3 months and 6 months after delivery.

<bold>Background and Objectives: </bold>Human milk has nutritional, protective, and developmental advantages for premature infants. However, proteomic information of low abundant protein of donor milk is insufficient. The purpose of this study is to analyze and compare the proteome of low abundant protein of donor milk obtained at different postpartum ages other than the colostrum.<bold>Methods and Study Design: </bold>Donor breast milk from 12 healthy mothers was collected 15 days, 2 months and 6 months after delivery and stored by medically approved methods. The whey milk proteomes were analyzed by mass spectrometry and classified using bioinformatics analysis.<bold>Results: </bold>Human milk obtained 15 days and 2 months after delivery showed more abundant expression of whey proteins related to the generation of precursor metabolites and energy, metabolism, and catalytic activity, compared with milk collected at 3 months. Immune and transport-related proteins were abundant at all time points. Proteins involved in cellular movement, immune cell trafficking, and the carbohydrate metabolism network was more abundant in whey milk collected at 15 day and 2 months using a network analysis.<bold>Conclusions: </bold>We report proteomic information for human donor whey protein. As significant changes were found in whey proteome collected earlier than 2 months and 6 months after delivery, selecting human donor milk earlier than 2 months might be more helpful for early postnatal recipients. [ABSTRACT FROM AUTHOR]