Ongoing immune system imbalance and blood clot inflammation in active Long Covid

Analysis of over 6,500 proteins in 268 blood samples revealed dysregulated activation of the complement system in individuals with Long Covid.

• Long Covid may involve ongoing issues with the complement system, which helps regulate immune responses.
• Increased activation of both the alternative and classical complement pathways was observed in these patients.
• Higher levels of antibodies against certain herpesviruses could be linked to the activation of the classical complement pathway.
• Signs of hemolysis, tissue damage, and platelet activation were also found to be elevated in individuals with Long Covid.
• Machine learning identified complement and thromboinflammatory proteins as important potential biomarkers for diagnosis and treatment.

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