Institute of Physiology, University of Zurich, Zurich, Switzerland.
Functional Genomics Center Zurich, Eidgenössische Technische Hochschule (ETH) Zurich and University of Zurich, Zurich, Switzerland.
Front Immunol. 2024 Sep 6;15:1404192. doi: 10.3389/fimmu.2024.1404192. eCollection 2024.
Breast milk is a vital source of nutrients, prebiotics, probiotics, and protective factors, including antibodies, immune cells and antimicrobial proteins. Using bacterial lipopolysaccharide arrays, we investigated the reactivity and specificity of breast milk antibodies towards microbial antigens, comparing samples from rural Kenya and urban Switzerland. Results showed considerable variability in antibody reactivity both within and between these locations. Kenyan breast milk demonstrated broad reactivity to bacterial lipopolysaccharides, likely due to increased microbial exposure. Antibodies primarily recognized the O-antigens of lipopolysaccharides and showed strong binding to specific carbohydrate motifs. Notably, antibodies against specific O-antigens showed cross-reactivity with parasitic pathogens like and , thus showing that antibodies reacting against lipopolysaccharide O-antigens can recognize a wide range of antigens beyond bacteria. The observed diversity in antigen recognition highlights the significance of breast milk in safeguarding infants from infections, particularly those prevalent in specific geographic regions. The findings also offer insights for potential immunobiotic strategies to augment natural antibody-mediated defense against diverse pathogens.
母乳是营养物质、益生元、益生菌和保护因子（包括抗体、免疫细胞和抗菌蛋白）的重要来源。我们使用细菌脂多糖阵列研究了母乳抗体对微生物抗原的反应性和特异性，比较了肯尼亚农村和瑞士城市的样本。结果表明，这些地点的抗体反应性在内部和之间都存在相当大的可变性。肯尼亚母乳对细菌脂多糖表现出广泛的反应性，可能是由于微生物暴露增加所致。抗体主要识别脂多糖的 O 抗原，并与特定的碳水化合物基序表现出强烈的结合。值得注意的是，针对特定 O 抗原的抗体与寄生虫病原体如 和 表现出交叉反应性，这表明针对脂多糖 O 抗原的抗体可以识别超出细菌范围的广泛抗原。观察到的抗原识别多样性突出表明母乳在保护婴儿免受感染方面的重要性，特别是在特定地理区域流行的感染。这些发现还为增强天然抗体介导的针对多种病原体的防御的潜在免疫生物策略提供了思路。
