Characterization of the pathogenic effects of Entamoeba gingivalis infection of gingival cells by transcriptome analysis and electron microscopy

The protozoan Entamoeba gingivalis colonizes the healthy oral mucosa with a prevalence of 15%. Colonization can be asymptomatic and it is considered that it is not pathogenic. However, it is able to invade lacerated oral mucosa where it ingests fragments of live cells, suggesting pathogenous potential. Here, we characterized the transcriptomes of gingival cells after infection with Entamoeba gingivalis using RNA Sequencing and observed pathogen interaction with the epithelial monolayer barrier by scanning electron microscopy. In epithelial and fibroblast cells, strongest differential expression showed gene set 'chemokines and inflammatory molecules in myeloid cells' (AUC=0.9, effect size 5.15, adj. P=3.1x10e-19) and “Cell cycle and growth arrest” (AUC=0.91 (effect size=4.56, adj. P=4.8x10e-9), respectively. The most upregulated genes in epithelial cells were TNF (fold change 430) and IL8 (fold change 359) and in fibroblasts ZN331 (fold change 18). We showed that Entamoeba gingivalis killed live epithelial cells by trogocytosis demonstrating strong pathogenic potential. Overall design: Single-end RNA-Seq of primary human fibroblasts or primary human endothelial cells stimulated with Entamoeba gingivalis