Int J Mol Sci . Human Milk Antibodies Against S1 and S2 Subunits from SARS-CoV-2, HCoV-OC43, and HCoV-229E in Mothers with A Confirmed COVID-19 PCR

[tetano]

Int J Mol Sci


. 2021 Feb 9;22(4):1749.
doi: 10.3390/ijms22041749.
Human Milk Antibodies Against S1 and S2 Subunits from SARS-CoV-2, HCoV-OC43, and HCoV-229E in Mothers with A Confirmed COVID-19 PCR, Viral SYMPTOMS, and Unexposed Mothers​

Veronique Demers-Mathieu[SUP] 1 2 [/SUP], Ciera DaPra[SUP] 1 [/SUP], Gabrielle Mathijssen[SUP] 1 [/SUP], David A Sela[SUP] 2 [/SUP], Kirsi M Jarvinen[SUP] 3 [/SUP], Antti Seppo[SUP] 3 [/SUP], Shawn Fels[SUP] 1 [/SUP], Elena Medo[SUP] 1 [/SUP]



Affiliations

• PMID: 33572480
• DOI: 10.3390/ijms22041749

Free article

Abstract

Preexisting immunity to SARS-CoV-2 could be related to cross-reactive antibodies to common human-coronaviruses (HCoVs). This study aimed to evaluate whether human milk antibodies against to S1 and S2 subunits SARS-CoV-2 are cross-reactive to S1 and S2 subunits HCoV-OC43 and HCoV-229E in mothers with a confirmed COVID-19 PCR test, in mothers with previous viral symptoms during COVID-19 pandemic, and in unexposed mothers; Methods: The levels of secretory IgA (SIgA)/IgA, secretory IgM (SIgM)/IgM, and IgG specific to S1 and S2 SARS-CoV-2, and reactive to S1 + S2 HCoV-OC43, and HCoV-229E were measured in milk from 7 mothers with a confirmed COVID-19 PCR test, 20 mothers with viral symptoms, and unexposed mothers (6 Ctl1-2018 and 16 Ctl2-2018) using ELISA; Results: The S2 SARS-CoV-2 IgG levels were higher in the COVID-19 PCR (p = 0.014) and viral symptom (p = 0.040) groups than in the Ctl1-2018 group. We detected a higher number of positive correlations between the antigens and secretory antibodies in the COVID-19 PCR group than in the viral symptom and Ctl-2018 groups. S1 + S2 HCoV-OC43-reactive IgG was higher in the COVID-19 group than in the control group (p = 0.002) but did not differ for the other antibodies; Conclusions: Mothers with a confirmed COVID-19 PCR and mothers with previous viral symptoms had preexisting human milk antibodies against S2 subunit SARS-CoV-2. Human milk IgG were more specific to S2 subunit SARS-CoV-2 than other antibodies, whereas SIgA and SIgM were polyreactive and cross-reactive to S1 or S2 subunit SARS-CoV-2.

Keywords: breast milk; breastfeeding; immunoglobulins; infectious diseases; neonates; passive immunity; polyreactive antibody; α-coronaviruses; β-coronaviruses.