The delicate balance between <i>Entamoeba histolytica</i>, mucus and microbiota

Abstract

<i>Entamoeba histolytica</i> (<i>Eh</i>) is a protozoan parasite of humans that colonizes the outer colonic mucus layer. Under conditions not fully understood, <i>Eh</i> breaches innate host defenses and invades the intestinal mucosa-causing amebic colitis and liver abscess. In asymptomatic infection, <i>Eh</i> interacts with and feeds on resident microbiota that forms biofilms on the outer colonic mucus layer. Despite the close association between <i>Eh</i> and commensal microbiota, we still lack basic knowledge on whether microbiota and/or their metabolites influence <i>Eh</i> virulence traits critical in disease pathogenesis. In the pathogenesis of intestinal amebiasis, <i>Eh</i> overcomes the protective mucus layer using a combination of mucinase/glycosidase and potent mucus secretagogue activity. In this addendum, we discuss the interconnected role of a healthy mucus barrier and the role commensal microbiota play in shaping innate host defense against <i>Eh</i>-induced pro-inflammatory and secretory responses critical in disease pathogenesis.