An Entamoeba sp. strain isolated from rhesus monkey is virulent but genetically different from Entamoeba histolytica☆

Molecular Testing for Clinical Diagnosis and Epidemiological Investigations of Intestinal Parasitic Infections

“…As a result, DNA amplification will occur but will probably not be detected by this assay. Whereas E. nuttalli appears to be virulent in nonhuman primates, at present, it remains unclear whether E. nuttalli can infect and cause disease in humans (53)(54)(55)(56)(57).…”

“…The morphology of cysts and trophozoite stages of E. bangladeshi appears similar to that of E. histolytica (49,51). Phylogenetic analysis of the relationship between E. bangladeshi and other Entamoeba parasites reveals that, although distinct, E. bangladeshi clearly groups with the clade of Entamoeba parasites infecting humans, which includes E. histolytica, E. dispar, and E. moshkovskii; this "complex" moreover contains two additional species that have not been found in humans so far, namely, E. ecuadoriensis (sewage) and E. nuttalli (nonhuman primates [NHPs]) (52,53). Of note, E. nuttalli differs from E. histolytica by 2 to 3 bp precisely in the DNA sequence of the E. histolytica detection probe of a widely used real-time PCR based on SSU rRNA genes of E. histolytica and E. dispar (28).…”

Primary pathogenicity analysis of a Chinese Entamoeba histolytica isolate

“…The genomic DNA was subjected to PCR for the amplification of hexokinase (HXK), glucose-6-phosphate isomerase (GPI), phosphoglucomutase (PGM), and heavy subunit of lectin genes (LecHgl). The primers and PCR conditions for E. histolytica were based on previously described procedures (8,9). PCR was performed briefly in a 50 μL reaction mixture using TaKaRa Ex-taq ® DNA Polymerase (Takara, Dalian, China).…”

DNA characterization of simian Entamoeba histolytica-like strains to differentiate them from Entamoeba histolytica

“…In non-human primates, several cases of E. histolytica or E. histolytica-like organism infections have been identified by isoenzyme analysis, monoclonal antibody test, or PCR (Tachibana et al 1990;Verweij et al 2003;Takano et al 2005;Tachibana et al 2007;Suzuki et al 2007). One of the simian E. histolyticalike strains, EHMfas1, has been isolated from a healthy cynomolgus monkey (Macaca fascicularis) and identified using species-specific PCR for E. histolytica and antigencapture ELISA (Takano et al 2005).…”

“…These two simian E. histolytica-like strains were suggested to be a new species, because EHMfas1 exhibits differences in the 16S-like small subunit ribosomal RNA (18S rDNA), chitinase and SREHP genes, and P19-061405 exhibits differences in several DNA sequences, including the 18S rDNA and SREHP genes (Takano et al 2007;Tachibana et al 2007). It has been proposed that P19-061405 should be distinguished from E. histolytica by revival of the name Entamoeba nuttalli (Castellani 1908) that was the first reported E. histolytica-like species found in a liver abscess of a monkey ).…”