Pathogenesis and Control of Chronic Infections, INSERM, EFS, Université de Montpellier, Montpellier, France.
Department of Bacteriology-Virology and Department of Medical Information, CHU Montpellier, Montpellier, France.
Pediatr Allergy Immunol. 2018 Mar;29(2):133-143. doi: 10.1111/pai.12841. Epub 2018 Jan 8.
Initiating breastfeeding within the first hour of life confers an important benefit in terms of child mortality and severe morbidity. Intestinal permeability to ingested macromolecules and immunoglobulins is limited to the first days of human life. These exchanges cease in the very early post-partum period but may increase beyond the neonatal period in response to local inflammation or introduction of a weaning food. From animal- and limited human-based observations, compelling evidence points out to breastmilk cells also trafficking from mother to infant mucosal tissues and participating to the maternal microchimerism. The precise nature of breastmilk cells that are involved is presently not known but likely includes progenitor/stem cells-representing up to 6% of breastmilk cells-with possible contribution of mature immune cells. Stem cell microchimerism may induce tolerance to non-inherited maternal antigens (NIMAs), breastfeeding generating regulatory T cells (T ) that suppress antimaternal immunity. Therefore, in complement to pregnancy-induced microchimerism, breastfeeding-induced microchimerism may be pivotal in infant immune development, intestinal tissue repair/growth and protection against infectious diseases. As a continuum of the gestational period, the neonatal gut may be considered as a temporary, but important developmental extension of the role played by the placenta during intrauterine life; breastmilk playing the role of maternal blood by delivering maternal soluble factors (macromolecules, Ig, cytokines) and immunologically active milk cells. A better understanding of breastfeeding-induced maternal microchimerism would provide further evidence in support of public health messages that reinforce the importance of early initiation of breastfeeding.
在生命的头一个小时内开始母乳喂养，对儿童死亡率和严重发病率有重要益处。肠道对摄入的大分子和免疫球蛋白的通透性仅限于人类生命的最初几天。这些交换在产后早期停止，但在局部炎症或引入断奶食物时可能会在新生儿期后增加。从动物和有限的人类观察中，有力的证据表明母乳细胞也从母亲转移到婴儿的黏膜组织，并参与母体微嵌合体。目前尚不清楚涉及的母乳细胞的确切性质，但可能包括祖细胞/干细胞-占母乳细胞的 6%-以及成熟免疫细胞的可能贡献。干细胞微嵌合体可能诱导对非遗传母体抗原 (NIMA) 的耐受，母乳喂养产生调节性 T 细胞 (T)，抑制抗母体免疫。因此，除了妊娠诱导的微嵌合体外，母乳喂养诱导的微嵌合体可能在婴儿免疫发育、肠道组织修复/生长和预防传染病方面发挥关键作用。作为妊娠期的延续，新生儿肠道可被视为胎盘在宫内生命期间发挥作用的临时但重要的发育延伸；母乳通过输送母体可溶性因子（大分子、Ig、细胞因子）和免疫活性的乳汁细胞来发挥母体血液的作用。更好地了解母乳喂养诱导的母体微嵌合体将为支持强化早期开始母乳喂养重要性的公共卫生信息提供进一步证据。
