Inhibition of complement component C3 reduces vein graft atherosclerosis in apolipoprotein E3-Leiden transgenic mice

Area of Science:

• Immunology
• Vascular Biology
• Surgical Research

Background:

• Vein graft failure is often caused by intimal hyperplasia and accelerated atherosclerosis.
• Inflammation is a key driver of these pathological processes.
• The complement system's role in vein graft atherosclerosis remains largely unexplored.

Purpose of the Study:

• To investigate the involvement of the complement cascade in the development of vein graft atherosclerosis.
• To determine if targeting complement could be a therapeutic strategy for vein graft failure.

Main Methods:

• A mouse model of venous interposition in the common carotid artery was utilized.
• Immunohistochemistry and quantitative mRNA analysis were performed to detect complement components (C1q, C3, C9) and regulatory proteins (CD59, complement receptor-related gene y).
• Interference with C3 activation using complement receptor-related gene y-Ig and inhibition of C3 with cobra venom factor were employed to assess therapeutic effects.

Main Results:

• Vein graft thickening and deposition of complement components (C1q, C3, C9) were observed within 4 weeks.
• Local mRNA expression of C1q, C3, CD59, and complement receptor-related gene y was detected in thickened grafts.
• Inhibition of C3 activation significantly reduced vein graft thickening, C3/C9 deposition, and inflammatory cell infiltration, while also affecting apoptosis and proliferation.

Conclusions:

• The complement cascade plays a significant role in vein graft thickening.
• Targeting complement activation, particularly C3, shows potential as a therapeutic approach to prevent vein graft failure.