Department of Pediatrics, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil.
Department of Pediatrics, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brazil; Universidade Paulista, UNIP, São Paulo, SP, Brazil.
Clinics (Sao Paulo). 2022 Aug 10;77:100093. doi: 10.1016/j.clinsp.2022.100093. eCollection 2022.
Human milk constitutes a secretion with unique functions of both nourishing the nursling and providing protection against enteric and respiratory infections, mainly due to its content of secretory IgA antibodies but also due to the presence of a plethora of bioactive factors. Specific IgA antibodies are produced locally by plasma cells derived from B lymphocytes that migrate from other mucosae to the mammary gland during lactation, particularly from the gastrointestinal and respiratory tracts. Therefore, here, the authors will provide a comprehensive review of the content and functions of different nutritional and bioactive anti-infectious components from breast milk, such as oligosaccharides, lactoferrin, haptocorrin, α-lactalbumin, k-casein, lysozyme, lactoperoxidase, mucin, fatty acids, defensins, cytokines and chemokines, hormones and growth factors, complement proteins, leukocytes and nucleic acids, including microRNAs, among many others, and the induction of antibody responses in breast milk after maternal vaccination with several licensed vaccines, including the anti-SARS-CoV-2 vaccine preparations used worldwide. Currently, in the midst of the pandemic, maternal vaccination has re-emerged as a crucial source of passive immunity to the neonate through the placenta and breastfeeding, considering that maternal vaccination can induce specific antibodies if performed during pregnancy and after delivery. There have been some reports in the literature about milk IgA antibodies induced by bacterial antigens or inactivated virus vaccines, such as anti-diphtheria-tetanus-pertussis, anti-influenza viruses, anti-pneumococcal and meningococcal polysaccharide preparations. Regarding anti-SARS-CoV-2 vaccines, most studies demonstrate elevated levels of specific IgA and IgG antibodies in milk with virus-neutralizing ability after maternal vaccination, which represents an additional approach to improve the protection of the nursling during the entire breastfeeding period.
人乳是一种具有独特功能的分泌液，既能滋养婴儿，又能提供针对肠道和呼吸道感染的保护，这主要归因于其分泌型 IgA 抗体的含量，但也归因于存在大量的生物活性因子。特定的 IgA 抗体由源自 B 淋巴细胞的浆细胞在哺乳期从其他黏膜迁移到乳腺中产生，特别是从胃肠道和呼吸道。因此，作者将全面回顾母乳中不同营养和抗感染生物活性成分的含量和功能，如寡糖、乳铁蛋白、触珠蛋白、α-乳白蛋白、κ-酪蛋白、溶菌酶、乳过氧化物酶、黏蛋白、脂肪酸、防御素、细胞因子和趋化因子、激素和生长因子、补体蛋白、白细胞和核酸，包括 microRNAs 等，以及母体接种多种已批准疫苗（包括全球使用的抗 SARS-CoV-2 疫苗制剂）后母乳中抗体反应的诱导。目前，在大流行期间，母体接种已重新成为通过胎盘和母乳喂养向新生儿提供被动免疫的重要来源，因为如果在怀孕期间和分娩后进行母体接种，可以诱导特异性抗体。文献中有一些关于细菌抗原或灭活病毒疫苗诱导的乳 IgA 抗体的报道，如抗白喉-破伤风-百日咳、抗流感病毒、抗肺炎球菌和脑膜炎球菌多糖制剂。关于抗 SARS-CoV-2 疫苗，大多数研究表明，母体接种后，母乳中具有病毒中和能力的特异性 IgA 和 IgG 抗体水平升高，这是在整个母乳喂养期间提高婴儿保护的另一种方法。
