Comparative Analysis of Whey Proteins in Human Milk Using a Data-Independent Acquisition Proteomics Approach during the Lactation Period

Human
milk (HM) is the primary source of nutrients and bioactive
components that supports the growth and development of infants. However,
the proteins present in human milk may change depending on the period
of lactation. In this light, the objective of the present study was
to evaluate the effect of lactation period on HM utilizing a data-independent
acquisition (DIA) approach to identify the differences in HM whey
protein proteomes. As part of the study, whey proteins of January,
February, and June in human milk were studied. The results identified
a total of 1563 proteins in HM whey proteins of which 114 groups were
subunits of differentially expressed proteins as revealed by cluster
analysis. Protein expression was observed to be affected by the period
of lactation with expression levels of plasminogen, thrombospondin-1,
and tenascin higher during January, keratin, type I cytoskeletal 9
highest in February, and transcobalamin-1 highest in June. The results
of this study contribute to expand our understanding of the human
whey proteome but also provide strong evidence for the nutritional
difference of HM during different lactation periods.