A high throughput immuno-affinity mass spectrometry method for detection and quantitation of SARS-CoV-2 nucleoprotein in human saliva and its comparison with RT-PCR, RT-LAMP, and lateral flow rapid antigen test.
Clin Chem Lab Med
; 62(6): 1206-1216, 2024 May 27.
Article
in En
| MEDLINE
| ID: mdl-38253336
ABSTRACT
OBJECTIVES:
Many reverse transcription polymerase chain reaction (RT-PCR) methods exist that can detect SARS-CoV-2 RNA in different matrices. RT-PCR is highly sensitive, although viral RNA may be detected long after active infection has taken place. SARS-CoV-2 proteins have shorter detection windows hence their detection might be more meaningful. Given salivary droplets represent a main source of transmission, we explored the detection of viral RNA and protein using four different detection platforms including SISCAPA peptide immunoaffinity liquid chromatography-mass spectrometry (SISCAPA-LC-MS) using polyclonal capture antibodies.METHODS:
The SISCAPA-LC MS method was compared to RT-PCR, RT-loop-mediated isothermal amplification (RT-LAMP), and a lateral flow rapid antigen test (RAT) for the detection of virus material in the drool saliva of 102 patients hospitalised after infection with SARS-CoV-2. Cycle thresholds (Ct) of RT-PCR (E gene) were compared to RT-LAMP time-to-positive (TTP) (NE and Orf1a genes), RAT optical densitometry measurements (test line/control line ratio) and to SISCAPA-LC-MS for measurements of viral protein.RESULTS:
SISCAPA-LC-MS showed low sensitivity (37.7â¯%) but high specificity (89.8â¯%). RAT showed lower sensitivity (24.5â¯%) and high specificity (100â¯%). RT-LAMP had high sensitivity (83.0â¯%) and specificity (100.0â¯%). At high initial viral RNA loads (<20 Ct), results obtained using SISCAPA-LC-MS correlated with RT-PCR (R2 0.57, p-value 0.002).CONCLUSIONS:
Detection of SARS-CoV-2 nucleoprotein in saliva was less frequent than the detection of viral RNA. The SISCAPA-LC-MS method allowed processing of multiple samples in <150â¯min and was scalable, enabling high throughput.Key words
Full text:
1
Database:
MEDLINE
Main subject:
Saliva
/
Mass Spectrometry
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RNA, Viral
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Molecular Diagnostic Techniques
/
SARS-CoV-2
/
COVID-19
Type of study:
Diagnostic_studies
Limits:
Adult
/
Female
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Humans
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Male
/
Middle aged
Language:
En
Journal:
Clin Chem Lab Med
/
Clin. chem. lab. med
/
Clinical chemistry and laboratory medicine
Journal subject:
QUIMICA CLINICA
/
TECNICAS E PROCEDIMENTOS DE LABORATORIO
Year:
2024
Type:
Article