Complement deficiencies in systemic lupus erythematosus

Area of Science:

• Immunology
• Genetics
• Rheumatology

Background:

• The complement system is a critical innate immunity component, bridging innate and adaptive immunity.
• It comprises over 30 proteins interacting sequentially through classical, lectin, and alternative activation pathways.
• Inherited deficiencies in complement components are rare but increase susceptibility to infections and autoimmune diseases.

Purpose of the Study:

• To review the associations between complement deficiencies and systemic lupus erythematosus (SLE).
• To elucidate the causal mechanisms linking complement deficiencies to SLE development.

Main Methods:

• Literature review of studies on complement deficiencies and SLE.
• Analysis of genetic and molecular mechanisms underlying the association.

Main Results:

• Deficiencies in early classical pathway complement components are strongly associated with SLE.
• Specific complement deficiencies predispose individuals to SLE through impaired immune complex clearance and altered immune regulation.

Conclusions:

• Complement deficiencies, particularly in early classical pathway components, are significant risk factors for SLE.
• Understanding these links is crucial for diagnosing and managing SLE patients with complement deficiencies.