The Role of Lipopeptidophosphoglycan in the Immune Response to Entamoeba histolytica

Abstract EN

The sensing of Pathogen Associated Molecular Patterns (PAMPs) by innate immune receptors, such as Toll-like receptors (TLRs), is the first step in the inflammatory response to pathogens.

Entamoeba histolytica, the etiological agent of amebiasis, has a surface molecule with the characteristics of a PAMP.

This molecule, which was termed lipopeptidophosphoglycan (LPPG), is recognized through TLR2 and TLR4 and leads to the release of cytokines from human monocytes, macrophages, and dendritic cells; LPPG-activated dendritic cells have increased expression of costimulatory molecules.

LPPG activates NKT cells in a CD1d-dependent manner, and this interaction limits amebic liver abscess development.

LPPG also induces antibody production, and anti-LPPG antibodies prevent disease development in animal models of amebiasis.

Because LPPG is recognized by both the innate and the adaptive immune system (it is a “Pamptigen”), it may be a good candidate to develop a vaccine against E.

histolytica infection and an effective adjuvant.