An ELISA-Based Method to Measure Mucosal Antibody Responses Against SARS-CoV-2 in Human Saliva

The primary mode of transmission for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is infection of the respiratory tract through droplets and/or aerosols. Therefore, immune responses at respiratory mucosal surfaces play a significant role in the prevention of infection. Greater emphasis is now being placed on mucosal immunity induced by exposure to SARS-CoV-2 antigens through infection or vaccination. In concert with cellular immunity, humoral responses at mucosal surfaces, especially the secretory version of immunoglobulin A (sIgA), can be instrumental in preventing respiratory infections. A better understanding of mucosal immune responses can further our knowledge of immunity to SARS-CoV-2 and help inform vaccine design. Here we describe a detailed protocol for an in vitro assay based on the enzyme-linked immunosorbent assay (ELISA) to assess mucosal antibody response to SARS-CoV-2 spike protein in human saliva. © 2024 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol: ELISA measurement of mucosal antibodies to SARS-CoV-2 spike protein in human saliva.