Bovine lactoferrin and its effects on innate immune cells in a complex milk matrix

Abstract

Human milk proteins provide a source of nutrition for the newborn infant but also are associated with biological functions. Lactoferrin is one of the major human milk proteins and has modulating effects on the immune system. This project determined the biological activity of bovine lactoferrin (bLF) on innate immune cells in the presence and absence of a liquid cow's milk based matrix (milk matrix) in vitro and in young mice. The expression of the costimulatory molecule CD80 on macrophages was significantly upregulated in vitro by human milk and the milk matrix. The greater expression by the milk matrix was reduced to the CD80 levels of human milk through the addition of bLF. The expression of CD80, CD86, and MHC class II on bone marrow‐derived dendritic cells (BMDCs) was upregulated by bLF and the milk matrix but not by human milk. Following oral administration of bLF to mice the respiratory burst capacity of neutrophils was determined. While the milk matrix had no effect, the levels were significantly decreased by human milk and bLF in the presence and absence of the milk matrix. Serum cytokine IL‐6 and IL‐12p40 levels were significantly reduced by the addition of bLF to the milk matrix. These studies demonstrate a biological role of bLF in a complex milk matrix in modulating the response of innate immune cells in in vitro and in vivo experiments.Research Support: provided by Mead Johnson Nutrition