Department of Microbiology-Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL.
J Immunol. 2024 Sep 1;213(5):612-618. doi: 10.4049/jimmunol.2400277.
Breast milk confers multiple benefits to the neonate, including passive immunity against multiple microorganisms via Abs. However, it remains unclear whether breast milk-derived Abs affect vaccine-induced immunity in the neonate. We evaluated in C57BL/6 and BALB/c mice whether breastfeeding from an mRNA-SARS-CoV-2-vaccinated dam affects vaccine-induced immunity in neonate mice. Using an experimental model that allows the distinction of maternal Abs and neonate Abs based on their allotype, we show that breastfeeding from an immune dam is associated with reduced vaccine immunity in the neonate. Importantly, mice that breastfed from an immune dam showed reduced numbers of plasma cells after vaccination, relative to mice that breastfed from a naive dam. Our subsequent studies using an mRNA-luciferase reporter system show that passive transfer of Abs through breastfeeding accelerates the clearance of vaccine Ag in suckling mice, resulting in reduced Ag availability. Altogether, maternal Abs transferred through breast milk can protect against infectious microorganisms, but they may also interfere with the neonate's response to vaccination by accelerating the clearance of vaccine Ag. These findings are important for understanding the effects of maternal Abs on the neonate's response to vaccines and may provide insights for improving neonatal vaccines.
母乳为新生儿提供多种益处，包括通过 Abs 提供针对多种微生物的被动免疫。然而，目前尚不清楚母乳衍生的 Abs 是否会影响新生儿的疫苗诱导免疫。我们在 C57BL/6 和 BALB/c 小鼠中评估了从接种 mRNA-SARS-CoV-2 疫苗的母鼠中进行母乳喂养是否会影响新生儿小鼠的疫苗诱导免疫。使用一种实验模型，该模型可以根据同种型区分母源 Abs 和新生儿 Abs，我们表明从免疫母鼠中进行母乳喂养与新生儿疫苗免疫降低有关。重要的是，与从未免疫母鼠中母乳喂养的小鼠相比，从免疫母鼠中母乳喂养的小鼠在接种疫苗后浆细胞数量减少。我们随后使用 mRNA-荧光素酶报告系统的研究表明，通过母乳喂养被动转移 Abs 会加速疫苗 Ag 在哺乳小鼠中的清除，从而导致 Ag 可用性降低。总之，通过母乳传递的母源 Abs 可以预防感染性微生物，但它们也可能通过加速疫苗 Ag 的清除来干扰新生儿对疫苗的反应。这些发现对于理解母源 Abs 对新生儿对疫苗的反应的影响很重要，并可能为改善新生儿疫苗提供思路。
