TY - JOUR
T1 - Development and Validation of an Enzyme Immunoassay for Detection and Quantification of SARS-CoV-2 Salivary IgA and IgG
AU - Costantini, Veronica P.
AU - Nguyen, Kenny
AU - Lyski, Zoe
AU - Novosad, Shannon
AU - Bardossy, Ana C.
AU - Lyons, Amanda K.
AU - Gable, Paige
AU - Kutty, Preeta K.
AU - Lutgring, Joseph D.
AU - Brunton, Amanda
AU - Thornburg, Natalie J.
AU - Brown, Allison C.
AU - McDonald, L. Clifford
AU - Messer, William
AU - Vinjé, Jan
N1 - Publisher Copyright:
Copyright © 2022 by The American Association of Immunologists, Inc. 0022-1767/22/$37.50
PY - 2022/3/15
Y1 - 2022/3/15
N2 - Oral fluids offer a noninvasive sampling method for the detection of Abs. Quantification of IgA and IgG Abs in saliva allows studies of the mucosal and systemic immune response after natural infection or vaccination. We developed and validated an enzyme immunoassay (EIA) to detect and quantify salivary IgA and IgG Abs against the prefusion-stabilized form of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein expressed in suspension-adapted HEK-293 cells. Normalization against total Ab isotype was performed to account for specimen differences, such as collection time and sample volume. Saliva samples collected from 187 SARS-CoV-2 confirmed cases enrolled in 2 cohorts and 373 prepandemic saliva samples were tested. The sensitivity of both EIAs was high (IgA, 95.5%; IgG, 89.7%) without compromising specificity (IgA, 99%; IgG, 97%). No cross-reactivity with endemic coronaviruses was observed. The limit of detection for SARS-CoV-2 salivary IgA and IgG assays were 1.98 ng/ml and 0.30 ng/ml, respectively. Salivary IgA and IgG Abs were detected earlier in patients with mild COVID-19 symptoms than in severe cases. However, severe cases showed higher salivary Ab titers than those with a mild infection. Salivary IgA titers quickly decreased after 6 wk in mild cases but remained detectable until at least week 10 in severe cases. Salivary IgG titers remained high for all patients, regardless of disease severity. In conclusion, EIAs for both IgA and IgG had high specificity and sensitivity for the confirmation of current or recent SARS-CoV-2 infections and evaluation of the IgA and IgG immune response. The Journal of Immunology, 2022, 208: 1500-1508.
AB - Oral fluids offer a noninvasive sampling method for the detection of Abs. Quantification of IgA and IgG Abs in saliva allows studies of the mucosal and systemic immune response after natural infection or vaccination. We developed and validated an enzyme immunoassay (EIA) to detect and quantify salivary IgA and IgG Abs against the prefusion-stabilized form of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein expressed in suspension-adapted HEK-293 cells. Normalization against total Ab isotype was performed to account for specimen differences, such as collection time and sample volume. Saliva samples collected from 187 SARS-CoV-2 confirmed cases enrolled in 2 cohorts and 373 prepandemic saliva samples were tested. The sensitivity of both EIAs was high (IgA, 95.5%; IgG, 89.7%) without compromising specificity (IgA, 99%; IgG, 97%). No cross-reactivity with endemic coronaviruses was observed. The limit of detection for SARS-CoV-2 salivary IgA and IgG assays were 1.98 ng/ml and 0.30 ng/ml, respectively. Salivary IgA and IgG Abs were detected earlier in patients with mild COVID-19 symptoms than in severe cases. However, severe cases showed higher salivary Ab titers than those with a mild infection. Salivary IgA titers quickly decreased after 6 wk in mild cases but remained detectable until at least week 10 in severe cases. Salivary IgG titers remained high for all patients, regardless of disease severity. In conclusion, EIAs for both IgA and IgG had high specificity and sensitivity for the confirmation of current or recent SARS-CoV-2 infections and evaluation of the IgA and IgG immune response. The Journal of Immunology, 2022, 208: 1500-1508.
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U2 - 10.4049/jimmunol.2100934
DO - 10.4049/jimmunol.2100934
M3 - Article
C2 - 35228262
AN - SCOPUS:85126072406
SN - 0022-1767
VL - 208
SP - 1500
EP - 1508
JO - Journal of Immunology
JF - Journal of Immunology
IS - 6
ER -