Table 1:
Laboratory-developed singleplex ELISA assays
| Sample Type | Antigen | Isotype | Assay Sensitivity & Specificity | Center/Institution | References | Regulatory Status |
|---|---|---|---|---|---|---|
| Serum, Plasma, Dried Plasma samples | RBD | IgG (IgA/IgM being eval) | Day 0–7 after infection: Sensitivity 73.01%; Day 8–14 after infection: Sensitivity 100%; Day ≥ 15 after infection: Sensitivity 100%; Specificity (n=388 samples collected prior to COVID-19 pandemic): 97.68% | Emory University | PMID: 32835303 | FDA EUA granted |
| Serum, Plasma | RBD and Spike | IgG, IgM, IgA | Sensitivity 95%, Specificity 100% (n=38 positive, n=74 negative sera tested) | Mount Sinai | PMID: 32302069, PMID: 32511441, PMID: 33142304 | FDA EUA granted |
| Serum, Plasma, Saliva | RBD | Total Ig, with IgG, IgM, IgA titers | Overall sensitivity 82.5%, overall specificity 100% (n=300); At > 14 days from symptom onset, sensitivity 100%, specificity 100% (n=261); | University of Minnesota | PMID: 32791053, PMID: 33539808 | Assays validated in a high-complexity testing CLIA laboratory |
| Serum, Plasma | RBD | IgG, IgM | Sensitivity: 91% for RBD IgG 15–21 days post onset of symptoms, 100% >21 days post-onset of symptoms; 90% for RBD IgM 15–21 days post onset of symptoms, 100% >21 days post-onset of symptoms. Specificity: 99.75% for RBD IgG, 100% for RBD IgM | Stanford University | PMID: 33288645 | Assays validated in a high-complexity testing CLIA laboratory |
| Serum, Plasma | RBD-ACE2 | Total IgG that blocks RBD-ACE2 binding | N/A, used as a follow-up assay in seropositive specimens | Stanford University | PMID: 33288645 | Assay validated in a high-complexity testing CLIA laboratory |
| Serum, Plasma | RBD | IgG, IgM + IgG | Sensitivity 98% (n=181), Specificity 98.9% (n=181). | University of Puerto Rico | PMID: 34696403, https://www.biorxiv.org/content/10.1101/2020.06.11.146332v2 | Assay validated in a high-complexity testing CLIA laboratory |
| Serum, Plasma | Spike | IgG | Sensitivity 98.3% (n=60), Specificity 99.3% (n=150) | Frederick National Laboratory | NR | RUO |
| Serum, Plasma | Spike | IgM | Sensitivity 93.8% (n=30), Specificity 97.6% (n=80) | Frederick National Laboratory | NR | RUO |
| Serum, Plasma | Nucleocapsid | IgG | Sensitivity 97% (n=34), Specificity 100% (n=99) | Frederick National Laboratory | NR | RUO |
| Serum, Plasma | Nucleocapsid | IgM | NR | Frederick National Laboratory | NR | RUO |
| Serum, Plasma, Saliva | RBD | Total Ig | Sensitivity 95% (n=259; 9 or more days after symptom onset), Specificity 96% (n=535) | University of North Carolina | PMID: 32527802, 35090596 | FDA EUA pending |
| Serum, Plasma, Saliva | Spike NTD | Total Ig | Sensitivity = 92% (n=259; 9 or more days after symptom onset), Specificity = 94% (n=535) | University of North Carolina | PMID: 35090596 | FDA EUA pending |
| Serum | Spike, RBD | IgG | NR | CVVR/BIDMC/Harvard | PMID: 34107529 | RUO |
| Serum, Plasma, Breast milk | RBD | IgG, IgA, IgM | NR | CVVR/BIDMC/Harvard | PMID: 33983379, PMID: 33893169 | RUO |
| Serum, Plasma | Spike | IgG | Sensitivity 100%, Specificity 98.8% | Tulane University | NR | RUO |
| Serum, Plasma | RBD | IgG | NR | Tulane University | NR | RUO |
| Serum, Plasma | Nucleocapsid | IgG | NR | Tulane University | NR | RUO |
| Plasma, Serum | Spike, RBD | IgM, IgG, IgA | Spike: IgG (Sensitivity 96.6%, Specificity 96.7%); IgA (Sensitivity 99.3%, Specificity 90%); IgM (Sensitivity 97.9%, Specificity 100%). RBD: IgG (Sensitivity 97.3%, Specificity 100%); IgA (Sensitivity 99.3%, Specificity 96.7%); IgM (Sensitivity 97.9%, Specificity 96.7%). IgG data based on n=126 convalescent plasma donors, n=30 pre-pandemic samples; IgM/IgA data based on n=20 hospitalized, n=30 pre-pandemic samples. | Johns Hopkins University | PMID: 32764200 | RUO |
| Serum, Plasma | Spike (ECD), RBD | IgG | NR | University of Texas-Austin | PMID: 32910806 | RUO |
| Serum, Plasma | RBD | IgG | Sensitivity 100% (n=155), Specificity 96.5% (n=133) | Arizona State University | NR | RUO |
| Serum, DBS | RBD | IgG, IgM | Sensitivity 97% (n=39), Specificity 100% (n=37) | University of Arkansas for Medical Sciences | PMID: 34478478, https://www.medrxiv.org/content/10.1101/2021.08.04.21261592v3 | RUO |
| Serum, DBS | RBD, Spike, Nucleocapsid | IgG, IgM | Sensitivity 97% (n=39), Specificity 100% (n=37) | University of Arkansas for Medical Sciences | PMID: 34478478, https://www.medrxiv.org/content/10.1101/2021.08.04.21261592v3 | RUO |
| Serum, Plasma, Breast milk | RBD, Spike, Nucleocapsid | IgG, IgM, IgA | 97% Sensitivity (n=114), Specificity 99% | University of Alabama Birmingham | NR | RUO |
| Serum, Plasma | RBD, Nucleocapsid,Spike Trimer | IgG, IgA | RBD: Sensitivity (70.9% for IgG, 74.4% for IgA) and Specificity (100% for both IgG and IgA); Nucleocapsid: Sensitivity (81.4% for IgG, 77.9% for IgA) and Specificity (98.5% for IgG, 100% for IgA); Spike Trimer: Sensitivity (67.4% for both IgG and IgA) and Specificity (98.5% for IgG, 100% for IgA). Data based on PCR confirmed COVID-19 hospitalized patients (n=86) and negative pre-pandemic samples (n=65). | University of Massachusetts Chan Medical School | PMID: 32780998 | RUO |
| Serum, Plasma | Nucleocapsid | IgG | Sensitivity 100% (n=44), Specificity 99.5% (n=202) | The Ohio State University | PMID: 33035201 | FDA EUA pending |
| Serum | Nucleocapsid | IgG | NR | The Ohio State University | NR | RUO |
| Oral fluid | Nucleocapsid | IgG | Sensitivity 92% (n=24), Specificity 98% (n=85) | Salimetrics | NR | RUO |
ACE2: Angiotensin converting enzyme-2; BIDMC: Beth Israel Deaconess Medical Center; CLIA: Clinical Laboratory Improvement Amendments; CVVR: Center for Virology and Vaccine Research; DBS: Dried blood spots; ECD: Extracellular domain; EUA: Emergency Use Authorization; FDA: Food and Drug Administration; NR: Not reported; NTD: N-terminal domain; PMID: PubMed Identifier; RBD: receptor binding domain; RUO: research use only