(P30-015-23) Egg Intake Alters Inflammatory Properties of HDL and Immune Cells Under Basal and Pathogenic Conditions, Which Uniquely Correlate With Changes in HDL Composition

Objectives: We have previously reported that intake of whole eggs vs. egg whites alters the lipidomic and proteomic composition of HDL – including changes in proteins involved in immune regulation. Thus, we investigated whether egg intake alters HDL inflammatory capacity of macrophages under basal and pathogenic (lipopolysaccharide (LPS)-stimulated) conditions, and whether similar inflammatory patterns were observable in subject-derived peripheral blood mononuclear cells (PBMCs).

Methods: We conducted a 16-week randomized, crossover intervention trial in which healthy men and women (n = 26) followed a 4-week egg-free diet, followed by random assignment to a 4-week diet period of consuming 3 whole eggs/day or 3 egg whites/day. Participants were then switched to the alternative egg treatment, separated by a second 4-week egg-free washout period. Fasted blood samples were collected after each diet period to measure PBMC inflammatory potential and isolate HDL for compositional analysis and inflammatory macrophage assays.

Results: We observed that interleukin-1β (IL-1β) secretion from RAW 264.7 macrophages was reduced by subject-derived HDL following whole egg intake in the absence of LPS, whereas LPS-induced tumor necrosis factor ɑ (TNFɑ) secretion was increased. In contrast, IL-1β production by subject-derived PBMCs was increased following the whole egg diet period under basal and LPS-stimulated conditions. Interestingly, we observed that changes in macrophage and PBMC cytokine production between egg white and whole egg diet periods correlated with distinct subsets of HDL lipid classes and proteins involved in lipid transport, immune activation, and pathogen defense, under basal vs. LPS-stimulated conditions. Further, PBMC IL-1β production under basal conditions negatively correlated with efflux capacity, whereas efflux capacity did not correlate with LPS-induced cytokine production by macrophages or PBMCs.

Conclusions: Intake of whole egg and egg whites differentially impacts the inflammatory properties of HDL and subject PBMCs, which uniquely correlate with changes in efflux capacity and HDL composition under basal and inflammatory challenge conditions.

Funding Sources: This study was funded by an Agriculture and Food Research Initiative Grant from the USDA National Institute of Food and Agriculture.