The Role of Dysfunctional HDL in Severe Sepsis

Study Summary

Severe sepsis results in over 300,000 Emergency Department (ED) visits and 215,000 deaths annually in the US. Currently there are no effective drug therapies for sepsis. High density lipoprotein (HDL) has antioxidant, anti-inflammatory, and antithrombotic properties and is protective in sepsis. Its functions in sepsis are primarily mediated by its main apolipoprotein, Apo-A1, that: 1) neutralize potent bacterial toxins, 2) protect blood vessel walls from damage, 3) prevent tissue damage through antioxidant properties, and 4) mediate thymocyte apoptosis (critical for survival) and endogenous corticosteroid release. However, recent literature presents inconsistent data on HDL functionality and shows that HDL becomes non-functional during acute inflammatory states called dysfunctional HDL (Dys-HDL). Several causes for Dys-HDL have been hypothesized including the presence of Apo A1 polymorphisms, which may worsen the pathologic inflammatory response in sepsis and have been demonstrated in early sepsis, making Dys-HDL an unstudied potential early marker. This project aims to: 1) determine the presence of Dys-HDL in adult patients with early severe sepsis who present to the ED (Dys-HDL will be tested using a novel cell free assay and HDL Inflammatory Index will be measured), and 2) examine the relationship between Dys-HDL and cumulative organ dysfunction via Sequential Organ Failure Assessment (SOFA) score. Results of this study could establish Dys-HDL as an early disease marker for sepsis which is influential in the development of sepsis-induced organ dysfunction.