BNT162b2 mRNA vaccine elicited antibody response in blood and milk of breastfeeding women

• Published in: Nature communications Vol. 12; no. 1; p. 6222
• Main Authors: Rosenberg-Friedman, Michal, Kigel, Aya, Bahar, Yael, Werbner, Michal, Alter, Joel, Yogev, Yariv, Dror, Yael, Lubetzky, Ronit, Dessau, Moshe, Gal-Tanamy, Meital, Many, Ariel, Wine, Yariv
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 28.10.2021; Nature Publishing Group; Nature Portfolio
• Subjects: 13/109; 631/250/2152/2153/1291; 631/250/255/2514; 631/250/590/2293; 631/326/596/4130; 82/1; 82/16; 82/80; 82/83; Adult; Animals; Antibodies; Antibody Formation - genetics; Antibody Formation - physiology; Antibody response; BNT162 Vaccine; Breast Feeding; Breastfeeding & lactation; Clinical trials; Coronaviruses; COVID-19; COVID-19 vaccines; COVID-19 Vaccines - genetics; Female; Health risks; Humanities and Social Sciences; Humans; Immunization; Immunoglobulin A; Immunoglobulin G; Infant mortality; Infants; Infections; Milk; Milk - chemistry; mRNA; mRNA Vaccines; multidisciplinary; Neutralization; Risk management; Risk reduction; RNA, Messenger - analysis; RNA, Messenger - blood; Science; Science (multidisciplinary); Vaccines; Vaccines, Synthetic - therapeutic use
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-021-26507-1

The importance of breastmilk in postnatal life lies in the strong association between breastfeeding and the reduction in the risk of infection and infection-related infant mortality. However, data regarding the induction and dynamics of breastmilk antibodies following administration of the Pfizer-BioNTech BNT162b2 COVID-19 mRNA vaccine is scarce, as pregnant and lactating women were not included in the initial vaccine clinical trials. Here, we investigate the dynamics of the vaccine-specific antibody response in breastmilk and serum in a prospective cohort of ten lactating women who received two doses of the mRNA vaccine. We show that the antibody response is rapid and highly synchronized between breastmilk and serum, reaching stabilization 14 days after the second dose. The response in breastmilk includes both IgG and IgA with neutralization capacity. Maternal antibodies can reduce risk of infection of infants. Here, the authors show induction of IgG and IgA antibodies in breastmilk and serum of ten lactating women after immunization with the Pfizer-BioNTech BNT162b2 COVID-19 mRNA vaccine.