Department of Maternal and Child Health, Policlinico Umberto I, Sapienza University of Rome, Rome, Italy.
B cell Unit, Immunology Research Area, Bambino Gesù Children's Hospital, 00165 Rome, Italy.
Clin Infect Dis. 2022 Aug 15;75(Suppl 1):S37-S45. doi: 10.1093/cid/ciac359.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been associated with adverse maternal and neonatal outcomes, yet uptake of SARS-CoV-2 vaccines during pregnancy and lactation has been slow. As a result, millions of pregnant and lactating women and their infants remain susceptible to the virus.
We measured spike-specific immunoglobulin G (anti-S IgG) and immunoglobulin A (anti-S IgA) in serum and breastmilk (BM) samples from 3 prospective mother-infant cohorts recruited in 2 academic medical centers. The primary aim was to determine the impact of maternal SARS-CoV-2 immunization vs infection and their timing on systemic and mucosal immunity.
The study included 28 mothers infected with SARS-CoV-2 in late pregnancy (INF), 11 uninfected mothers who received 2 doses of the BNT162b2 vaccine in the latter half of pregnancy (VAX-P), and 12 uninfected mothers who received 2 doses of BNT162b2 during lactation. VAX dyads had significantly higher serum anti-S IgG compared to INF dyads (P < .0001), whereas INF mothers had higher BM:serum anti-S IgA ratios compared to VAX mothers (P = .0001). Median IgG placental transfer ratios were significantly higher in VAX-P compared to INF mothers (P < .0001). There was a significant positive correlation between maternal and neonatal serum anti-S IgG after vaccination (r = 0.68, P = .013), but not infection.
BNT161b2 vaccination in late pregnancy or lactation enhances systemic immunity through serum anti-S immunoglobulin, while SARS-CoV-2 infection induces mucosal over systemic immunity more efficiently through BM immunoglobulin production. Next-generation vaccines boosting mucosal immunity could provide additional protection to the mother-infant dyad. Future studies should focus on identifying the optimal timing of primary and/or booster maternal vaccination for maximal benefit.
严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）感染与母婴不良结局相关，但在妊娠和哺乳期接种 SARS-CoV-2 疫苗的速度缓慢。因此，数以百万计的孕妇和哺乳期妇女及其婴儿仍然容易感染该病毒。
我们测量了来自 2 个学术医疗中心招募的 3 个前瞻性母婴队列的血清和母乳（BM）样本中的刺突特异性免疫球蛋白 G（抗-S IgG）和免疫球蛋白 A（抗-S IgA）。主要目的是确定母体 SARS-CoV-2 感染和免疫及其时间对全身和黏膜免疫的影响。
该研究包括 28 名在妊娠晚期感染 SARS-CoV-2 的母亲（INF）、11 名未感染的母亲在妊娠后半期接受了 2 剂 BNT162b2 疫苗（VAX-P）和 12 名未感染的母亲在哺乳期接受了 2 剂 BNT162b2 疫苗。VAX 对的血清抗-S IgG 明显高于 INF 对（P<0.0001），而 INF 母亲的 BM：血清抗-S IgA 比值高于 VAX 母亲（P=0.0001）。与 INF 母亲相比，VAX-P 中的 IgG 胎盘转移比值明显更高（P<0.0001）。接种疫苗后，母亲和新生儿血清抗-S IgG 之间存在显著正相关（r=0.68，P=0.013），但与感染无关。
BNT161b2 疫苗在妊娠晚期或哺乳期接种可通过血清抗-S 免疫球蛋白增强全身免疫，而 SARS-CoV-2 感染通过 BM 免疫球蛋白产生更有效地诱导黏膜免疫超过全身免疫。下一代增强黏膜免疫的疫苗可为母婴对提供额外的保护。未来的研究应集中于确定母体接种的最佳时间，以实现最大效益。
