Circulating antibodies recognizing oxidatively modified low-density lipoprotein in children

Area of Science:

• Immunology
• Cardiovascular Science
• Biochemistry

Background:

• Circulating antibodies against oxidatively modified low-density lipoprotein (LDL) are implicated in cardiovascular disease.
• The presence and significance of these antibodies in healthy children are not well understood.

Purpose of the Study:

• To investigate the occurrence of IgG antibodies against oxidatively modified LDL in healthy children and adults.
• To characterize the antigens recognized by these antibodies and the oxidation state of LDL.

Main Methods:

• Quantification of IgG antibodies against copper-oxidized LDL and malondialdehyde-derivatized LDL (MDA-LDL) in children and adults.
• Analysis of LDL oxidation products and apo B100 modification.
• Assessment of LDL's propensity for in vitro oxidation.

Main Results:

• Healthy children consistently showed increased titers of IgG recognizing oxidized LDL and MDA-LDL compared to adults.
• Antibodies recognized epitopes formed late in LDL oxidation, associated with aldehyde-protein adducts.
• LDL from children exhibited higher in vitro oxidation susceptibility despite normal alpha-tocopherol levels.

Conclusions:

• Circulating antibodies recognizing lipid peroxidation end-products, including modified LDL, are present in healthy children.
• The findings suggest that LDL oxidation may occur in vivo during childhood.
• This early-life oxidation could be a potential immunogen, warranting further investigation into its role in cardiovascular health.