Project description:The ability of Entamoeba histolytica to phagocytose host cells correlates to observed virulence in vivo. To better understand the mechanism of phagocytosis we used paramagnetic beads coated with host ligand and sorted trophozoites based on phagocytic ability. Gene expression was then measured in both the sorted phagocytic and non-phagocytic populations using a custom Affymetrix chip for E. histolytica. Feed forward regulation of phagocytosis by Entamoeba histolytica. Infection and Immunity. PMID 23045476
Project description:Differential expression was used to access gene differences after Entamoeba histolytica infection. Entamoeba histolytica is an important diarrheal pathogen worldwide, and induces apoptosis of the intestinal epithelium as part of its disease process. Regenerating (REG) 1 protein is anti-apoptotic. We investigated the involvement of REG 1 in E. histolytica colitis. Colonic biopsy samples were obtained from 8 subjects with acute E. histolytica colitis, and again 60 day later during convalescence. Gene expression in the human colon during acute and convalescent E. histolytica disease was evaluated using microarray and confirmed by polymerase chain reaction (PCR). REG 1 protein expression was evaluated with immunohistochemistry. The mechanism of REG 1 involvement in E. histolytica disease was subsequently investigated with a mouse model. REG 1A and REG 1B were the most upregulated genes in the human intestine in acute versus convalescent E. histolytica disease (p=0.003 and p=0.006 respectively). PCR confirmed the microarray results (p=<0.001 and p=0.001 respectively). Increased REG 1A and REG 1B protein expression was similarly observed by immunohistochemistry. REG 1 -/-mice were found to be significantly more susceptible to E. histolytica infection than wild type mice.
Project description:The enteric protozoan parasite Entamoeba histolytica have high phagocytic ability. Phagocytosis is also important for the pathogenicity of this parasite; molecular mechanisms of phagocytosis and phagosome maturation is focused. Atg8 is well studied autophagy marker protein. We previously shown that E. histolytica Atg8 translocate to nascent trogosomes and expression silencing of the Atg8 caused retardation of phagosome acidification. To investigate how Atg8 regulates phagosome maturation, here we conducted proteome analysis of phagosomes isolated from an E. histolytica strain in which atg8 gene expression are silenced (atg8 gene silenced, atg8-gs) and its mock control strain (transfected with psAP2-Gunma).
Project description:To know the role of Rab7 isotypes in enteric protozoan parasite Entamoeba histolytica, one out of nine Rab7 isotypes, Rab7D, was specifically silenced and examined the effect on virulence-related phenotypes. To clarify transcriptomic difference caused by rab7d gene silencing, RNA-seq analysis was conducted.
Project description:Entamoeba histolytica trophozoites epigenetically silenced for ameobapore A (G3 parasites) were additionally silenced for the Rhomboid gene Rom1 (EHI_197460) using the mechanism outlined in Mirelman et al. Parasite. 2008 Sep;15(3):266-74 (PMID 18814693). Rom1 silencing was confirmed by RT-PCR. Gene expression in these parasites was compared to that of the parent G3 strain.
