Table 2:
Laboratory-developed multiplex assays
| Sample Type | Antigen | Isotype | Assay Sensitivity & Specificity | Center/Institution | References | Regulatory Status |
|---|---|---|---|---|---|---|
| DBS, Serum | Spike S1, Nucleocapsid | IgG | Sensitivity: DBS 94% for symptomatic (n=774 samples collected >20 days after PCR+ result) 85% for asymptomatic (n=115 samples collected >20 days after PCR+ result), Specificity: DBS 99% (n=730), Serum 99% (n=701) | Wadsworth | PMID: 32648546 PMID: 34319133 | NYS CLEP-approved |
| Serum, Plasma, DBS | Spike, Nucleocapsid, RBD | Total Ig | Sensitivity >97%, Specificity 99% | Wadsworth | PMID: 33104179 | FDA EUA granted; NYS CLEP-approved |
| Serum, Plasma, DBS | Spike, Nucleocapsid, RBD | IgG, IgM, IgA | Sensitivity >97%, Specificity 99% | Wadsworth | PMID: 34151306 | NYS CLEP-approved; FDA EUA pending |
| Oral fluid, Serum, Plasma | Spike, RBD, Nucleocapsid | IgG, IgM, IgA | Oral fluid IgG assay sensitivity 98.8% ≥ 15 days post symptom onset (n=81), specificity 100% (n=127) | Johns Hopkins University, Supporting Michigan State University | PMID: 33067270, 34695724 | Oral fluid assays validated in a high-complexity testing CLIA laboratory; Serum/plasma RUO |
| Serum, Plasma, BAL, DBS | Spike, RBD (different variants), Nucleocapsid | IgG | Sensitivity >97% sensitivity (n=89), Specificity 99% (n=260) | Case Western Reserve University | PMID: 33993265 | RUO |
| Serum, Plasma, Saliva, BAL | Spike, RBD, Nucleocapsid | IgA | Sensitivity >98%, Specificity 99% | Case Western Reserve University | PMID: 33993265 | RUO |
| Serum, Plasma | Spike | IgG | Sensitivity ≥ 93%, Specificity 100% | NIST | PMID: 33800363 | RUO |
| Serum, Plasma | RBD | IgG | Sensitivity ≥ 93%, Specificity 100% | NIST | PMID: 33800363 | RUO |
| Serum, Plasma | RBD, Nucleocapsid | IgG | Nucleocapsid Sensitivity 90.3% (n=155) and Specificity 98.0% (n=133); RBD Sensitivity 90.1% (n=155) and Specificity 97.0% (n=133) | Arizona State University | NR | FDA EUA pending |
| Serum | Spike, Nucleocapsid, RBD | IgG, IgM, IgA | NR | Yale | PMID: 33171100 | RUO |
| Serum | Alpha, Beta, Gamma, and Delta variants (Spike, RBD) | IgG, IgM, IgA | NR | Yale | PMID: 31229590 | RUO |
| Saliva | Spike, Nucleocapsid, RBD | IgG | Sensitivity: Nucleocapsid 97.7%, RBD 92.9%, Spike 98.8%; Specificity: Nucleocapsid 95.2%, RBD 96.4%, Spike 97.6%. (Combined Nucleocapsid & Spike sensitivity 96.5%, specificity 98.8%) | Salimetrics | NR | RUO |
| Serum, Plasma | Spike S1, S1-RBD, Nucleocapsid, S1-NTD | IgG, IgA, IgM (combined) IgG, IgA, IgM (individual) | Sensitivity: combined antigens and isotypes 99%; S1-RBD combined isotypes 99%, S1-RBD IgG 99%; Specificity: combined antigens and isotypes 99%, S1-RBD combined isotypes 99%, S1-RBD IgG 99%. During the acute phase, Sensitivity 92%, Specificity 99%. | Emory/MicroB-plex | PMID: 34001652 | RUO |
BAL: Bronchoalveolar lavage; CLIA: Clinical Laboratory Improvement Amendments; DBS: Dried blood spots; EUA: Emergency use authorization; FDA: Food and Drug Administration; NIST: National Institute of Standards and Technology; NR: Not reported; NYS CLEP: New York State Clinical Laboratory Evaluation Program; PCR: Polymerase chain reaction; PMID: PubMed Identifier; RBD: Receptor binding domain; RUO: Research use only