Selective functional antibody transfer into the breastmilk after SARS-CoV-2 infection

 After SARS-CoV-2 infection to mothers, antibody responses were observed both in maternal serum and breast milk. IgA and IgM were dominantly released into the breast milk, whereas IgGs in the breast milk were functionally attenuated. These antibodies were capable of eliciting neutrophil phagocytosis and neutralization, indicating that selective functional antibodies were released into the breast milk.