Klein Laura D, Huang Jincui, Quinn Elizabeth A, Martin Melanie A, Breakey Alicia A, Gurven Michael, Kaplan Hillard, Valeggia Claudia, Jasienska Grazyna, Scelza Brooke, Lebrilla Carlito B, Hinde Katie
Department of Human Evolutionary Biology, Harvard University, 11 Divinity Avenue, Cambridge, MA, USA.
Department of Anthropology, University of Illinois at Chicago, 1007 West Harrison Street, Chicago IL, USA.
Evol Med Public Health. 2018 Oct 13;2018(1):230-245. doi: 10.1093/emph/eoy031. eCollection 2018.
Adaptive immune proteins in mothers' milk are more variable than innate immune proteins across populations and subsistence strategies. These results suggest that the immune defenses in milk are shaped by a mother's environment throughout her life.
Mother's milk contains immune proteins that play critical roles in protecting the infant from infection and priming the infant's developing immune system during early life. The composition of these molecules in milk, particularly the acquired immune proteins, is thought to reflect a mother's immunological exposures throughout her life. In this study, we examine the composition of innate and acquired immune proteins in milk across seven populations with diverse disease and cultural ecologies.
Milk samples ( = 164) were collected in Argentina, Bolivia, Nepal, Namibia, Philippines, Poland and the USA. Populations were classified as having one of four subsistence patterns: urban-industrialism, rural-shop, horticulturalist-forager or agro-pastoralism. Milk innate (lactalbumin, lactoferrin and lysozyme) and acquired (Secretory IgA, IgG and IgM) protein concentrations were determined using triple-quadrupole mass spectrometry.
Both innate and acquired immune protein composition in milk varied among populations, though the acquired immune protein composition of milk differed more among populations. Populations living in closer geographic proximity or having similar subsistence strategies (e.g. agro-pastoralists from Nepal and Namibia) had more similar milk immune protein compositions. Agro-pastoralists had different milk innate immune protein composition from horticulturalist-foragers and urban-industrialists. Acquired immune protein composition differed among all subsistence strategies except horticulturist-foragers and rural-shop.
Our results reveal fundamental variation in milk composition that has not been previously explored in human milk research. Further study is needed to understand what specific aspects of the local environment influence milk composition and the effects this variation may have on infant health outcomes.
与先天免疫蛋白相比，母乳中的适应性免疫蛋白在不同人群和生存策略中更具变异性。这些结果表明，母乳中的免疫防御是由母亲一生的环境塑造的。
母乳中含有免疫蛋白，这些蛋白在保护婴儿免受感染以及在婴儿生命早期启动其免疫系统发育方面发挥着关键作用。母乳中这些分子的组成，尤其是获得性免疫蛋白，被认为反映了母亲一生的免疫暴露情况。在本研究中，我们调查了七个具有不同疾病和文化生态的人群母乳中先天免疫蛋白和获得性免疫蛋白的组成。
在阿根廷、玻利维亚、尼泊尔、纳米比亚、菲律宾、波兰和美国收集了164份母乳样本。人群被分类为具有四种生存模式之一：城市工业化、农村商店经营、园艺采集或农牧结合。使用三重四极杆质谱法测定母乳中先天（乳白蛋白、乳铁蛋白和溶菌酶）和获得性（分泌型IgA、IgG和IgM）蛋白的浓度。
母乳中先天和获得性免疫蛋白的组成在不同人群中有所不同，尽管母乳中获得性免疫蛋白的组成在不同人群中的差异更大。地理位置相近或生存策略相似的人群（例如尼泊尔和纳米比亚的农牧民）母乳免疫蛋白组成更相似。农牧民的母乳先天免疫蛋白组成与园艺采集者和城市工业化人群不同。除园艺采集者和农村商店经营者外，所有生存策略的获得性免疫蛋白组成均存在差异。
我们的结果揭示了母乳组成的基本差异，这在以前的母乳研究中尚未被探讨过。需要进一步研究以了解当地环境的哪些具体方面会影响母乳组成以及这种差异可能对婴儿健康结果产生的影响。
