IgA dominates the early neutralizing antibody response to SARS-CoV-2

Humoral immune responses are typically characterized by primary IgM antibody responses followed by secondary antibody responses associated with immune memory and composed of IgG, IgA, and IgE. Here, we measured acute humoral responses to SARS-CoV-2, including the frequency of antibody-secreting cells and the presence of SARS-CoV-2-specific neutralizing antibodies in the serum, saliva, and bronchoalveolar fluid of 159 patients with COVID-19. Early SARS-CoV-2-specific humoral responses were dominated by IgA antibodies. Peripheral expansion of IgA plasmablasts with mucosal homing potential was detected shortly after the onset of symptoms and peaked during the third week of the disease. The virus-specific antibody…

• AN
  Agence Nationale de la Recherche

  Awards: 10-INSB-04-01, ANR-10-INSB-04-01, ANR-10, ANR-10-INSB-04
• IN
  Institut National de la Santé et de la Recherche Médicale
• AP
  Assistance Publique - Hôpitaux de Paris
• FD
  Fondation de France
• AP
  Assistance publique-Hôpitaux de Paris
• SU
  Sorbonne Université