Apolipoprotein A1 (ApoA1) is a major protein component of high-density lipoprotein (HDL) in plasma, playing a critical role in cholesterol metabolism. It is synthesized in the liver and intestines and is essential for forming HDL particles. ApoA1 serves as a cofactor for lecithin-cholesterol acyltransferase (LCAT), which is key to HDL particle maturation and the reverse cholesterol transport pathway, where cholesterol is moved from tissues back to the liver for excretion.
Function
ApoA1 is pivotal in reverse cholesterol transport, which removes excess cholesterol from peripheral tissues and prevents atherosclerosis. In addition to its role in cholesterol transport, ApoA1 has anti-inflammatory and antioxidant properties, providing additional protection against cardiovascular diseases (CVD).
Clinical Significance
ApoA1 levels are inversely correlated with cardiovascular risk; higher ApoA1 and HDL levels are associated with lower risks of atherosclerosis and CVD. Due to its strong association with cardiovascular health, ApoA1 can also serve as a substitute for HDL-C in RISK calculations for CVD, offering a direct measure of HDL function rather than simply HDL quantity.
Genetic Aspects
The APOA1 gene, located on chromosome 11, encodes ApoA1. Genetic mutations in APOA1 can lead to conditions like HDL deficiencies and systemic amyloidosis, which affect lipid metabolism and cardiovascular health.
Measurement
Blood ApoA1 levels are measured using methods like immunoassays (e.g., ELISA), valued for their specificity and sensitivity. ApoA1 measurement is frequently part of lipid profiling to assess cardiovascular risk and guide clinical management of CVD prevention.
Dried Blood Spots
Apolipoprotein A1 (ApoA1) can also be measured in Dried Blood Spots (DBS), making it easier to assess cardiovascular health in settings where traditional blood sampling is challenging. Vitas offers the AM-467 assay for the quantification of ApoA1 in both human plasma and DBS using ELISA, providing precise and accessible testing options.