Hanson L A, Carlsson B, Dahlgren U, Mellander L, Svanborg Edén C
Ciba Found Symp. 1979(77):187-204. doi: 10.1002/9780470720608.ch12.
It is still not known when the secretory IgA response, important for defence of the mucous membranes, becomes fully competent in the human infant. The infant is, however, provided with 0.25--0.5 g of secretory IgA/day via the maternal milk. The milk contains secretory IgA antibodies against a wide variety of antigens from microorganisms, including bacteria, viruses and parasites. Many of the antibodies are directed against important virulence factors such as bacterial pili, enterotoxins, capsular polysaccharides and endotoxic lipopolysaccharides. The passive transfer of antibodies through the milk may explain why breast-fed infants are resistant to enteric infections in particular. The antibodies in the milk are often directed against antigens in the mother's milieu and intestine. An entero-mammary gland link, possibly consisting of lymphoid cells homing from the Peyer's patches in the intestine to the mammary gland, has been suggested. A limited selective uptake of oligomeric IgA from serum in exocrine glands, including the mammary glands, has also been indicated. Whichever the mechanism, the antibodies transferred via breast milk are composed to meet the needs of the infant.
对于人类婴儿而言，对粘膜防御很重要的分泌型IgA反应何时完全具备功能仍不清楚。然而，婴儿每天通过母乳可获得0.25 - 0.5克分泌型IgA。母乳中含有针对多种微生物抗原的分泌型IgA抗体，这些微生物包括细菌、病毒和寄生虫。许多抗体针对重要的毒力因子，如细菌菌毛、肠毒素、荚膜多糖和内毒素脂多糖。抗体通过母乳的被动转移可能解释了为什么母乳喂养的婴儿尤其对肠道感染具有抵抗力。母乳中的抗体通常针对母亲环境和肠道中的抗原。有人提出存在肠 - 乳腺联系，可能由从肠道派伊尔结归巢至乳腺的淋巴细胞组成。也有迹象表明，包括乳腺在内的外分泌腺会有限地选择性摄取血清中的寡聚IgA。无论机制如何，通过母乳转移的抗体都是为满足婴儿的需求而构成的。
