Serum Protein N-Glycans in Colostrum and Mature Milk of Chinese Mothers

Abstract

To study the Chinese human milk N-glycome over lactation, N-glycans were released and separated from serum proteins, purified by solid phase extraction, and analysed by MALDI-TOF-MS. In total, 66 different putative N-glycans were found in colostrum (week 1) and mature milk (week 4) of 7 Chinese mothers. A clear difference was observed between milk of 5 secretor and 2 non-secretor mothers, based on the type and relative amounts of the individual N-glycans. The relative levels of the total neutral nonfucosylated and the fucosylated N-glycans in milk of 5 secretor mothers increased and decreased over lactation, respectively. This pattern could not be observed for the milk from the 2 non-secretor mothers. Overall, this was the first study that provided detailed information on individual N-glycans in milk among mothers and over time, and that fucosylation of N-glycans in milk was associated with the mother’s secretor status.