Abstract

Breastmilk protects newborns from infections through specific and nonspecific compounds. This study investigated the neutralizing activity against SARS-CoV-2 of breastmilk from SARS-CoV-2 negative, unvaccinated mothers, and compared it to that from infected nursing mothers. We enrolled women after COVID-19 swab testing results upon maternity admission, and divided them into two groups: group A, COVID-19-positive mothers, and group B, negative mothers. Breastmilk was randomly sampled at 2, 7, and 20 days postpartum. We collected 19 samples for Group A and 41 for Group B. A microneutralization assay was used to determine the 50% neutralization (NT50) titre. The presence of neutralizing antibodies was also determined. Group A had 100% neutralizing samples at 2 days postpartum (T0), declining 7 days postpartum (T1) and 20 days postpartum (T2). Group B samples exhibited neutralizing activity mostly at 7 days postpartum (T1) (90%). Negative mothers' samples showed no correlation between NT50 titres and antibodies' presence, suggesting that non-specific breastmilk components may exert antiviral action against SARS-CoV-2.

Details

Title
Breastmilk from COVID-19 negative lactating mothers shows neutralizing activity against SARS-COV-2
Author
Morniroli, Daniela 1 ; Signorini, Lucia 2 ; Dolci, Maria 2 ; Vizzari, Giulia 3 ; Ronchi, Andrea 3 ; Pietrasanta, Carlo 1 ; Pugni, Lorenza 3 ; Mosca, Fabio 1 ; Delbue, Serena 2 ; Gianni, Maria Lorella 1 

 University of Milan, Department of Clinical Sciences and Community Health, Milan, Italy (GRID:grid.4708.b) (ISNI:0000 0004 1757 2822); Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, NICU, Milan, Italy (GRID:grid.414818.0) (ISNI:0000 0004 1757 8749) 
 University of Milan, Department of Biomedical, Surgical and Dental Sciences, Milan, Italy (GRID:grid.4708.b) (ISNI:0000 0004 1757 2822) 
 Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, NICU, Milan, Italy (GRID:grid.414818.0) (ISNI:0000 0004 1757 8749) 
Pages
15521
Publication year
2023
Publication date
2023
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2866257212
Copyright
© The Author(s) 2023. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.