Robust and Specific Secretory IgA Against SARS-CoV-2 Detected in Human Milk—Fox 2020

Protecting newborns and young children against COVID-19 is crucial to minimizing community transmission and preventing major disease and death, but the SARS-CoV-2 immune response in human milk has not been studied. The SARS-CoV-2 Spike protein was evaluated in milk samples from eight COVID-19-recovered and seven COVID-19-suspected donors. All samples showed substantial specific IgA reactivity to the entire Spike, and 80% showed IgA and secretory (s)Ab binding to the RBD. 67% samples bound IgG or IgM to RBD. Most IgA was sIgA because sAb titers were significantly linked. These findings suggest a strong sIgA-dominant SARS-CoV-2 Ab response in human milk following infection in most people. Ab functionality and milk sIgA therapeutic usage need further study.

Fox, A., Marino, J., Amanat, F., Krammer, F., Hahn-Holbrook, J., Zolla-Pazner, S., & Powell, R. L. (2020). Robust and Specific Secretory IgA Against SARS-CoV-2 Detected in Human Milk. iScience, 23(11), 101735. https://doi.org/10.1016/j.isci.2020.101735