Serum HDL and their subfractions are impaired in multisystem inflammatory syndrome in children (MIS-C)

Area of Science:

• Immunology
• Cardiovascular Research
• Pediatric Infectious Diseases

Background:

• Multisystem inflammatory syndrome in children (MIS-C) is a severe post-COVID-19 condition characterized by a hyperimmune response.
• High-density lipoproteins (HDL) play a crucial role in modulating inflammation and immune responses through their subfractions.

Purpose of the Study:

• To investigate the role of serum cholesterol, HDL, and HDL subfractions (HDL-SUB) in the pathogenesis of MIS-C.
• To determine the potential of HDL and HDL-SUB as diagnostic biomarkers for MIS-C.

Main Methods:

• Serum levels of cholesterol, HDL, and HDL-SUB were analyzed using capillary electrophoresis.
• These lipid parameters were correlated with biomarkers of inflammation and endothelial damage measured by microfluidic immunoassays.
• The study included 48 MIS-C patients at hospital admission and 48 age- and sex-matched healthy controls.

Main Results:

• MIS-C patients exhibited significantly lower serum cholesterol and HDL levels compared to controls.
• Serum cholesterol inversely correlated with inflammation biomarkers, indicating cytokine impact on reverse cholesterol transport.
• HDL levels inversely correlated with endothelial damage biomarkers, suggesting HDL's role in MIS-C endothelial dysfunction. A remodeling of HDL-SUB was observed, with a decrease in anti-inflammatory small HDL particles.

Conclusions:

• The study confirms a severe impairment of reverse cholesterol transport in MIS-C.
• Serum HDL and HDL-SUB show promise as valuable diagnostic biomarkers for MIS-C.