Elevated Salivary Inflammatory Biomarkers are Associated with SARS-CoV-2 Infection Severity

Area of Science:

• Immunology
• Infectious Diseases
• Biomarker Discovery

Background:

• Elevated serum inflammatory cytokines are linked to severe SARS-CoV-2.
• Salivary biomarkers are gaining attention for diagnosing systemic diseases.
• Investigating salivary inflammatory markers could differentiate SARS-CoV-2 severity.

Purpose of the Study:

• To assess salivary interleukin-6 (IL-6), C-reactive protein (CRP), and C-X-C motif chemokine ligand-10 (CXCL-10) levels.
• To determine if these biomarkers can distinguish between mild and severe SARS-CoV-2 infections.
• To explore correlations between biomarkers, patient demographics, and comorbidities.

Main Methods:

• Saliva samples collected from 142 controls and 158 SARS-CoV-2 patients (72 mild, 86 severe).
• Quantification of IL-6, CRP, and CXCL-10 using immunoassay techniques.
• Statistical analysis to compare biomarker levels across groups and identify correlations.

Main Results:

• IL-6 and CXCL-10 were elevated in both mild and severe SARS-CoV-2 cases.
• CRP was significantly increased only in severe SARS-CoV-2 cases.
• All biomarkers were significantly higher in severe cases compared to mild cases (p < 0.001).
• Higher biomarker levels observed in males, elderly patients, and those with diabetes or hypertension.
• Significant positive correlations found between IL-6, CRP, CXCL-10, and age.

Conclusions:

• Salivary IL-6, CRP, and CXCL-10 levels correlate with SARS-CoV-2 infection severity.
• Saliva holds potential for non-invasive monitoring of COVID-19 severity and therapeutic response.
• Biomarker profiles may aid in personalized patient management for SARS-CoV-2 infection.