New Insights into the Role of the Complement System in Human Viral Diseases

Area of Science:

• Immunology
• Virology

Background:

• The complement system (CS) comprises over 30 proteins integral to innate and adaptive immunity.
• It defends against pathogens, including viruses, through three activation pathways: classical (CP), lectin (LP), and alternative (AP).
• Complement activation culminates in the membrane attack complex (MAC), causing target cell lysis.

Purpose of the Study:

• To review the significant role of the complement system in viral diseases.
• To explore the CS's involvement in respiratory diseases, acute liver failure (ALF), disseminated intravascular coagulation (DIC), and vector-borne diseases (VBDs).
• To highlight implications for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) research.

Main Methods:

• Literature review focusing on complement system research in viral etiologies.
• Analysis of studies examining the CS in four specific disease categories: respiratory, ALF, DIC, and VBDs.

Main Results:

• The CS plays a complex role in the pathogenesis and resolution of various viral infections.
• Evidence links CS dysregulation to severe outcomes in respiratory diseases, ALF, DIC, and VBDs.
• Understanding CS mechanisms offers potential therapeutic targets for viral diseases, including SARS-CoV-2.

Conclusions:

• The complement system is a critical factor in managing viral infections and associated pathologies.
• Further research into the CS in viral diseases is essential for developing effective treatments and public health strategies.
• Collaboration with global health organizations is vital for addressing emerging viral threats involving the CS.