Cell-specific and divergent roles of the CD40L-CD40 axis in atherosclerotic vascular disease

Area of Science:

• Immunology
• Cardiovascular Biology
• Molecular Medicine

Background:

• Atherosclerosis is a significant contributor to cardiovascular disease.
• The CD40 ligand (CD40L)-CD40 signaling pathway is a known target for attenuating atherosclerosis.
• CD40L has diverse functions dependent on cell interactions, necessitating investigation into specific cell types.

Purpose of the Study:

• To investigate the distinct roles of CD40L-expressing T cells and platelets in atherosclerosis.
• To elucidate the function of the CD40L-CD40 axis involving T cells and dendritic cells in atherogenesis.
• To determine the impact of platelet CD40L on atherosclerosis and atherothrombosis.

Main Methods:

• Utilizing atherosclerosis-prone mouse models with cell-specific CD40L or CD40 deficiencies (CD4+ T cells, CD11c+ dendritic cells, platelets).
• Assessing atherosclerotic plaque development, immune cell infiltration, and plaque composition.
• Measuring plasma and plaque concentrations of soluble CD40L (sCD40L), soluble CD40 (sCD40), and interferon-gamma (IFN-γ) in patients.

Main Results:

• CD40L deficiency in T cells or CD40 deficiency in dendritic cells led to smaller atherosclerotic plaques with reduced Th1 polarization and interferon-γ production.
• The T cell-dendritic cell CD40L-CD40 axis was identified as crucial in atherogenesis.
• Platelet-specific CD40L deficiency did not affect atherosclerosis but ameliorated atherothrombosis.
• Positive correlations were observed between sCD40L/sCD40 and IFN-γ levels in human carotid plaques and plasma.

Conclusions:

• The CD40L-CD40 pathway exhibits divergent, cell-specific roles in atherosclerosis and atherothrombosis.
• Targeting the T cell-dendritic cell CD40L-CD40 axis holds promise for treating atherosclerosis.
• Modulating platelet CD40L may be beneficial for preventing atherothrombotic events.