Learning from the research on amebiasis and gut microbiome: Is stimulation by gut flora essential for effective neutrophil mediated protection from external pathogens?

Abstract

Amebiasis, caused by intestinal infection with Entamoeba histolytica, is one of the leading causes of parasite infection-related mortality and morbidity globally. Although its pathogenesis, including determinant factors of infection outcome, remains unclear, recent clinical data indicate that the gut microbiome plays a role in determining the severity of amebiasis. Recently, we investigated the effects of the gut microbiome on neutrophil mediated protection from E. histolytica infection using a mouse model. We identified that surface expression of CXCR2 on neutrophils was diminished in mice with dysbiosis, which resulted in decreased neutrophil recruitment to the infection site, allowing more aggressive intestinal tissue damage by E. histolytica. Our results indicated that oxidase activity during E. histolytica infection was also diminished after dysbiosis, consistent with the results from prior research. Thus, the gut microbiome plays an important role in regulating neutrophil phenotype when fighting against external pathogens.

The Immune System in Transfusion-Related Acute Lung Injury Prevention and Therapy: Update and Perspective

“…Neutrophil recruitment to inflamed tissues involves elements of neutrophil rolling and firm adhesion ( Filippi, 2019 ). To capture extracellular pathogen-associated molecules and other stimuli, neutrophils release decondensed chromatin coated with granular proteins, which form neutrophil extracellular traps (NETs) ( Branzk et al, 2014 ; Storisteanu et al, 2017 ; Watanabe and Petri, 2019 ). However, the secretion of NETs can also cause tissue damage at the expense of the host and has been shown to impair wound healing or facilitate lung injury in diabetes ( Wong et al, 2015 ) and ventilator-induced lung injury ( Yildiz et al, 2015 ).…”

Both living and dead Faecalibacterium prausnitzii alleviate house dust mite‐induced allergic asthma through the modulation of gut microbiota and short‐chain fatty acid production

“…23 This insight firmly supports the concept that the balance between immune tolerance and inflammation within tissues is partly influenced by the crosstalk between immune cells and the microbiome. [24][25][26] The disruption of communication between the host and the microbiome can be detrimental to the efficient maturation of the immune system, resulting in a risk of development of inflammatory disorders, such as asthma and respiratory infections. 27,28 Therefore, strategies to ensure the proper development of the immune system and to preserve a health-promoting microbiota are considered in the prevention of asthma and allergyrelated diseases.…”

Neutrophils vs. amoebas: Immunity against the protozoan parasiteEntamoeba histolytica

“…Thus, it seems that NETosis operates as an innate immune defense mechanism against pathogenic amoebas. Also, the effector functions of neutrophils can be modified by the microbiota 32–34 in a manner leading to less severe forms of amoebiasis 35,36 . This review describes the mechanisms of E. histolytica infection and discusses the novel view of how neutrophils are involved in protection from amoebiasis.…”