Complex changes in serum protein levels in COVID-19 convalescents

Area of Science:

• Proteomics
• Immunology
• Biochemistry

Background:

• The COVID-19 pandemic caused by SARS-CoV-2 has led to extensive research on disease severity.
• However, less is understood about the long-term physiological changes and recovery patterns in individuals after infection.

Purpose of the Study:

• To investigate and quantify proteomic differences in serum samples between COVID-19 convalescents and healthy controls.
• To identify specific protein alterations associated with the recovery phase of COVID-19.

Main Methods:

• Serum proteome quantification was performed on 29 COVID-19 convalescents and 29 matched healthy controls.
• Mass spectrometry-based proteomics was used to analyze protein expression levels.

Main Results:

• Most proteins involved in acute COVID-19 pathways (complement, coagulation, inflammation, adaptive immunity) returned to normal levels in convalescents.
• 22 proteins were significantly elevated and 15 were decreased in COVID-19 convalescents compared to controls.
• Elevated levels of lipid metabolism proteins (CETP, APOA1) and decreased levels of complement/coagulation proteins (C1R, C1S, VWF, THBS1) were observed.
• Race-specific differences in immunoglobulin and cholesterol metabolism proteins were noted.

Conclusions:

• While many acute COVID-19 related proteins normalize during recovery, specific proteomic shifts persist.
• These persistent changes may involve lipid metabolism, complement and coagulation systems, and actin cytoskeleton regulation.
• Potential links to transient platelet count changes and race-specific variations warrant further investigation.