Detection of breastmilk antibodies targeting SARS-CoV-2 nucleocapsid, spike and receptor-binding-domain antigens

ABSTRACT

A 40-year-old female was found to have strongly neutralizing SARS-CoV-2 breastmilk IgA and IgG antibodies reactive against multiple SARS-CoV-2 antigens at 2.5 months after documented infection with SARS-CoV-2. At 6.5 months following the infection, she remained positive for breastmilk and serum SARS-CoV-2 neutralizing antibodies. Holder breast milk pasteurization did not diminish SARS-CoV-2 antibody titres but it reduced its neutralizing capacity, while serum heat inactivation had no negative effect on SARS-CoV-2 serum antibody levels and neutralizing capacity. Current data on SARS-CoV-2 and breastmilk are reviewed.

KEYWORDS:

• SARS-CoV-2
• COVID-19
• antibody
• IgG
• IgA
• breastmilk

Acknowledgements

Dr LC James (Medical Research Council Laboratory of Molecular Biology, Cambridge, UK) for the SARS-CoV-2 N-protein; Dr JAG Briggs (Medical Research Council Laboratory of Molecular Biology, Cambridge, UK) for the SARS-CoV-2 trimeric S-protein; Dr JA Nathan (University of Cambridge, Cambridge, UK) for the SARS-CoV-2 RBD-protein; Dr Nigel Temperton (University of Kent, Canterbury, UK) for the pCAGGS_TMPRSS2, pCAGGS_hACE-2, p8.91 and pCSFLW plasmids, and Dr Edward Wright (University of Sussex, Brighton, UK) for the HEK293T/17 cell line. We thank the index case for granting us permission to publish this work.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was funded by the Addenbrooke’s Charitable Trust, UK [grant number 900256].