Alteration of circulating natural antibodies against VEGFR1-derived peptide antigens in atherosclerosis

Background Several lines of evidence suggest the protective role of natural antibody in common chronic disease like atherosclerosis and cancer. Vascular endothelial growth factor receptors 1 (VEGFR1) and 2 (VEGFR2) are important regulators of angiogenesis and their involvement in developing atherosclerosis cannot be ruled out. Purpose The present study was designed to develop an in-house enzyme-linked immunosorbent assay to test if natural IgG for VEGFR1 and regulatory T cell markers CD25 and FOXP3 could be associated with atherosclerosis. Methods A total of 218 patients with atherosclerosis and 200 healthy controls were recruited; all patients had atherosclerotic carotid plaque and carotid intima–media thickness was analyzed using a diagnostic ultrasound system. Results Mann-Whitney U test demonstrated that plasma anti-VEGFR1 IgG levels were significantly lower in atherosclerosis patients than control subjects (Z=-2.46, P =0.014) although neither anti-CD25 IgG levels nor anti-FOXP3 IgG levels showed significant changes. Male patients mainly contributed to the decreased antiVEGFR1 IgG levels (Z=-2.45, P =0.014). Spearman correlation analysis failed to show any significant correlation between natural IgG levels and carotid intima–media thickness. Conclusion Decreased levels of anti-VEGFR1 IgG may be involved in developing atherosclerosis-related conditions.