Clinical and Analytical Performance of ELISA Salivary Serologic Assay to Detect SARS-CoV-2 IgG in Children and Adults
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Design and Sample Collection
2.2. Samples Analysis
2.3. Precision Assessment
2.4. Linearity Assessment
2.5. Impact of Sample Collection Time on Salivary Ab Levels
2.6. Statistical Analyses
2.7. Ethical Statement
3. Results
3.1. Performance Verification and Precision Analysis
3.2. Linearity Assessment
3.3. Clinical Study
3.4. Impact of Sample Collection Time on Salivary Ab
4. Discussion
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Overall | Children | Adults | p-Value * | |
---|---|---|---|---|
n | 187 | 95 (50.8%) | 92 (49.2%) | - |
Age (mean ± SD) | 24.66 ± 17.15 | 9.01 ± 3.3 | 40.8 ± 8.4 | t = 34.4, p < 0.001 |
Gender | 105/82 (F/M) | 49/46 (F/M) | 56/36 (F/M) | Fisher’s exact test, p = 0.239 |
Comorbidities | 30/187 (16.0%) | 17/95 (17.9%) | 13/92 (14.1%) | Fisher’s exact test, p = 0.552 |
Prolonged therapy | 25/183 ^ | 16/94 (17.0%) ^ | 9/89 (10.1%) ^ | Fisher’s exact test, p = 0.201 |
Previous SARS-CoV-2 infection | 154/187 (82.35%) | 80/95 (84.21%) | 74/92 (80.43%) | Fisher’s exact test, p = 0.567 |
Time from last COVID-19 or vaccination (median and IQR $) | 175.3 ± 82.7 | 174.5 ± 72.5 | 176.1 ± 92.3 | t = 0.119, p = 0.904 |
Salivary N/S RBD IgG (kAU/L) | 29.7 (0.5–87.4) | 2.96 (0.5–67.5) | 50.6 (0.5–127.6) | χ2 = 6.4, p = 0.019 |
Anti SARS-CoV-2 S-RBD IgG (kBAU/L) (median and IQR $) | 1672.5 (514.4–3345.8) | 1138.8 (321.3–2706.3) | 2022.9 (808.4–4118.3) | χ2 = 10.4, p = 0.001 |
Time from Vaccine-Induced Immunization or Time from SARS-CoV-2 Infection | Salivary N/S IgG (kAU/L), Median (IQR), (n) | Serum S-RBD IgG (kBAU/L) Median (IQR), (n) | ||
---|---|---|---|---|
Children | Adults | Children | Adults | |
<113 days | 2.01 (0.5 to 18.1) (n = 21) | 59.4 (2.02 to 117.9) (n = 22) | 1719 (526 to 3596) (n = 21) | 3136 (1382 to 4178) (n = 22) |
113 to 180 days | 12.2 (0.5 to 60.7) (n = 16) | 73.8 (0.5 to 192.0) (n = 23) | 1302 (431 to 2521) (n = 16) | 2319 (419 to 5364) (n = 23) |
181 to 210 days | 31.9 (0.5 to 110.2) (n = 28) | 47.5 (0.5 to 68.8) (n = 17) | 1426 (378 to 2821) (n = 28) | 1961 (787 to 3345) (n = 17) |
>210 days | 2.2 (0.5 to 47.1) (n = 30) | 49.1 (1.3 to 328.5) (n = 30) | 800 (89 to 2340) (n = 30) | 1585 (800 to 5523) (n = 30) |
Children | Adults | |||
---|---|---|---|---|
Variables | Coefficients (95%CI) | p-Value | Coefficients (95%CI) | p-Value |
Age | 0.13 (0.07–0.20) | p < 0.001 | −0.03 (−0.59–(−0.001)) | p = 0.040 |
Gender | 0.09 (−0.37–0.55) | p = 0.686 | 0.13 (−0.37–0.63) | p = 0.600 |
Comorbidities | −0.50 (−1.08–0.09) | p = 0.095 | −0.57 (−1.27–0.13) | p = 0.110 |
Prolonged therapy | −0.57 (−1.12–0.09) | p = 0.092 | −0.06 (−0.89–0.78) | p = 0.890 |
Previous SARS-CoV-2 infection | 0.10 (−0.58–0.76) | p = 0.770 | −0.52 (−1.12–0.09) | p = 0.750 |
Time from last COVID-19 or vaccination | −0.001 (−0.004–0.001) | p = 0.316 | 0.0001 (−0.003–0.004) | p = 0.730 |
Children | Adults | |||
---|---|---|---|---|
Variables | Coefficients (95%CI) | p-Value | Coefficients (95%CI) | p-Value |
Age | 0.08 (0.20–0.15) | p = 0.010 | −0.01 (-0.23–0.01) | p = 0.550 |
Gender | 0.04 (−0.35–0.44) | p = 0.830 | 0.04 (−0.26–(0.35)) | p = 0.780 |
Comorbidities | −0.86 (−1.34–(−0.38)) | p = 0.001 | −0.61 (−1.01–(−0.2)) | p = 0.004 |
Prolonged therapy | −0.95 (−1.43–(−0.48)) | p < 0.001 | −0.33 (−0.83–0.16) | p = 0.190 |
Previous SARS-CoV-2 infection | 0.95 (0.43–1.47) | p = 0.001 | 0.29 (−0.08–0.67) | p = 0.120 |
Time from last COVID-19 or vaccination | 0.0001 (−0.002–0.003) | p = 0.910 | −0.001 (−0.003–0.0003) | p = 0.110 |
log10 Salivary Anti-SARS-CoV-2 N/S IgG | log10 Anti-SARS-CoV-2 S-RBD IgG | |||
---|---|---|---|---|
Children | Adults | Children | Adults | |
Coefficients (95%CI), p-Value | Coefficients (95%CI), p-Value | Coefficients (95%CI), p-Value | Coefficients (95%CI), p-Value | |
Age | 33.9 (14.5 to 53.3), p = 0.001 | −2.99 (−13.30 to 7.31), p = 0.565 | 0.093 (0.044 to 0.142), p < 0.001 | −0.002 (−0.019 to 0.015), p = 0.785 |
Gender | 134.9 (5.6 to 264.1), p = 0.041 | 176.4 (−2.9 to 355.6), p = 0.054 | 0.22 (−0.09 to 0.54), p =1.44 | 0.16 (−0.12 to 0.45), p = 0.266 |
Comorbidities | 219.9 (−56.9 to 496.7), p = 0.158 | −153.5 (−524.3 to 217.4), p = 0.412 | 0.355 (−0.351 to 1.062), p = 0.320 | −0.93 (−1.53 to −0.34), p = 0.002 |
Prolonged therapy | −45.7 (−327.2 to 235.7), p = 0.747 | 226.3 (−191.9 to 644.5), p = 0.285 | −0.43 (−1.12 to 0.26), p = 0.218 | 0.42 (−0.25 to 1.09), p = 0.216 |
Previous SARS-CoV-2 infection | 130.9 (−89.6 to 351.6), p = 0.152 | −68.7 (−295.9 to 158.4), p = 0.548 | 0.21 (−0.31 to 0.73), p = 0.429 | 0.11 (−0.25 to 0.48), p = 0.533 |
Time from last COVID-19 or vaccination (days) | −0.82 (−1.71 to 0.07), p = 0.070 | −0.099 (−1.073 to 0.874), p = 0.839 | 0.0002 (−0.002 to 0.002), p = 0.856 | −0.001 (−0.003 to 0.0003), p = 0.109 |
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Padoan, A.; Cosma, C.; Di Chiara, C.; Furlan, G.; Gastaldo, S.; Talli, I.; Donà, D.; Basso, D.; Giaquinto, C.; Plebani, M. Clinical and Analytical Performance of ELISA Salivary Serologic Assay to Detect SARS-CoV-2 IgG in Children and Adults. Antibodies 2024, 13, 6. https://doi.org/10.3390/antib13010006
Padoan A, Cosma C, Di Chiara C, Furlan G, Gastaldo S, Talli I, Donà D, Basso D, Giaquinto C, Plebani M. Clinical and Analytical Performance of ELISA Salivary Serologic Assay to Detect SARS-CoV-2 IgG in Children and Adults. Antibodies. 2024; 13(1):6. https://doi.org/10.3390/antib13010006
Chicago/Turabian StylePadoan, Andrea, Chiara Cosma, Costanza Di Chiara, Giulia Furlan, Stefano Gastaldo, Ilaria Talli, Daniele Donà, Daniela Basso, Carlo Giaquinto, and Mario Plebani. 2024. "Clinical and Analytical Performance of ELISA Salivary Serologic Assay to Detect SARS-CoV-2 IgG in Children and Adults" Antibodies 13, no. 1: 6. https://doi.org/10.3390/antib13010006