Triacylglycerides and Phospholipids from Egg Yolk Differently Influence the Immunostimulating Properties of Egg White Proteins

Abstract

As part of a whole egg, egg white proteins are embedded in a lipid matrix that could modify their presentation to the immune system and their allergenic properties. The present study examines the impact of the main egg lipid components, triacylglycerides and phospholipids, in the early events of sensitization to egg. To this end, BALB/c mice were exposed intragastrically to egg lipids and egg lipid fractions, alone and in mixtures with egg white proteins, and Th2-promoting and proinflammatory effects were investigated. Our results highlight that the egg lipid fraction is responsible for Th2 adjuvant effects and point at a different influence of triacylglycerides and phospholipids on the bioavailability and immunomodulating properties of egg white proteins. While triacylglycerides promote type 2 responses at the small intestine level, phospholipids reduce the solubility of EW proteins and induce Th2 skewing in lymphoid intestinal tissues, which may have a direct impact on the development of egg allergy.

Egg yolk lipids induce sensitization to egg white proteins in a mouse model without adjuvant and exacerbate Th2 responses to egg white in cells from allergic patients

“…In line with our previous acute administration study (Pérez-Rodríguez et al, 2021) the present results also suggest that egg proteins combined with TG were preferentially absorbed through IECs, whereas PL contributed to the delivery of antigens to lymphoid organs. The different effect of triglycerides and phospholipids on antigen uptake was confirmed in the absorption of OVA, the most abundant and allergenic egg white protein (Benedé et al, 2015).…”

Critical features of an in vitro intestinal absorption model to study the first key aspects underlying food allergen sensitization

“…Conversely, co‐administration of shorter chain triacylglycerols or other lipids that are preferentially taken up through Peyer's patches favored subsequent transport of proteins to the draining mesenteric lymph nodes and increased their immunogenicity (Li, Wang, et al., 2013). Moreover, a recent study reported that egg phospholipids reduce the solubility of egg white proteins in simulated duodenal fluid, impairing epithelial absorption and promoting antigen delivery to Peyer's patches (Pérez‐Rodríguez et al., 2021).…”