Jiang Rulan, Lönnerdal Bo
Curr Opin Clin Nutr Metab Care. 2016 May;19(3):214-9.
Osteopontin (OPN) is an extensively phosphorylated acidic glycoprotein that is present at high concentration in human milk. Bovine milk OPN has recently become commercially available, and can thus be added to infant formula as well as other food products. Studies in experimental animals as well as a clinical trial in human infants reveal important biological roles for milk OPN.
Newborn wild-type mice nursing knock-out dams lacking milk OPN showed impaired cognitive development, reduced brain OPN and myelin-related proteins as compared with pups nursing wild-type dams. Transcriptomic analysis of intestinal biopsies from infant rhesus monkeys fed formula with added bovine milk OPN showed that OPN positively regulated intestinal proliferation, cell migration, and cellular chemotaxis via binding to integrin receptors. A clinical trial on human infants fed formula with added bovine milk OPN showed significantly reduced levels of serum tumor necrosis factor a and fewer days of fever as compared with infants fed regular formula. Further, their immune cell profile was more similar to that of breast-fed infants.
Milk OPN affects immune functions, and intestinal development in the newborn as well as brain development in a mouse model. Addition of bovine milk OPN to infant formula may improve the performance of formula-fed infants and make them more similar to breast-fed infants. Due to its multiple functions, milk OPN is also used for various adult applications.
骨桥蛋白（OPN）是一种高度磷酸化的酸性糖蛋白，在人乳中含量很高。牛乳OPN最近已商业化，因此可添加到婴儿配方奶粉以及其他食品中。对实验动物的研究以及对人类婴儿的一项临床试验揭示了乳OPN的重要生物学作用。
与吸食野生型母鼠乳汁的幼崽相比，吸食缺乏乳OPN的基因敲除母鼠乳汁的新生野生型小鼠认知发育受损，脑OPN和髓鞘相关蛋白减少。对喂食添加了牛乳OPN配方奶粉的恒河猴婴儿的肠道活检组织进行转录组分析表明，OPN通过与整合素受体结合，正向调节肠道增殖、细胞迁移和细胞趋化性。一项针对喂食添加了牛乳OPN配方奶粉的人类婴儿的临床试验表明，与喂食常规配方奶粉的婴儿相比，其血清肿瘤坏死因子α水平显著降低，发热天数减少。此外，他们的免疫细胞谱与母乳喂养婴儿的更相似。
乳OPN影响新生儿的免疫功能、肠道发育以及小鼠模型中的脑发育。在婴儿配方奶粉中添加牛乳OPN可能会改善配方奶喂养婴儿的表现，使其更接近母乳喂养婴儿。由于其多种功能，乳OPN还用于各种成人应用。
