Evidence map›Paper›PMID 42298609›Full record

ArticleGut pathogens2026

Entamoeba histolytica clones presenting transient virulent phenotypes: subsequent fate of forcibly induced virulent clones by hamster's liver abscess model.

Yumiko Saito-Nakano, Shinji Izumiyama, Yasuaki Yanagawa, Seiki Kobayashi, Yuko Umeki, Takashi Makiuchi, Kumiko Nakada-Tsukui, Koji Watanabe

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Article in Gut pathogens, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

8 authors.

Yumiko Saito-Nakano *Department of Parasitology, National Institutes of Infectious Diseases, Japan Institute for Health Security, Tokyo, Japan.
Shinji Izumiyama *Department of Parasitology, National Institutes of Infectious Diseases, Japan Institute for Health Security, Tokyo, Japan.
Yasuaki Yanagawa *Department of Parasitology, National Institutes of Infectious Diseases, Japan Institute for Health Security, Tokyo, Japan.
Seiki KobayashiDepartment of Parasitology, National Institutes of Infectious Diseases, Japan Institute for Health Security, Tokyo, Japan.
Yuko UmekiDepartment of Parasitology, National Institutes of Infectious Diseases, Japan Institute for Health Security, Tokyo, Japan.
Takashi MakiuchiDepartment of Parasitology, Division of Host Defense Mechanism, Tokai University School of Medicine, 143 Shimokasuya, Isehara, 259-1193, Kanagawa, Japan.
Kumiko Nakada-TsukuiDepartment of Parasitology, National Institutes of Infectious Diseases, Japan Institute for Health Security, Tokyo, Japan.
Koji WatanabeDepartment of Parasitology, National Institutes of Infectious Diseases, Japan Institute for Health Security, Tokyo, Japan. kwatanab@tokai.ac.jp.

Funding

Japan Agency for Medical Research and Development JP23fk0108680h0001Japan Agency for Medical Research and Development JP24fk0108683JST, CREST Japan JPMJCR23B5National Center for Global Health and Medicine 23A2017Shionogi Infectious Disease Research Promotion Foundation 2024S026
6 · The paper itself

Abstract

backgroundAmebiasis, which is caused by Entamoeba histolytica, is prevalent worldwide. Clinical presentation varies from asymptomatic infection to life-threatening extraintestinal disease, and the clinical form can change within one infectious episode. It is also known that periodical animal passages are required for maintaining virulence of E. histolytica in vivo model, such as a hamster liver abscess or murine colitis model. However, it remains uncertain whether or for how long virulence induced by environmental stimuli persists during in vitro passage at the clonal level.

resultsWe generated clones from a hamster liver-passaged E. histolytica strain and periodically checked their liver abscess-forming capability during subsequent in vitro passages. We obtained three clones (ALA-1, ALA-5, and ALA-6) that were highly virulent (abscess weight accounting for > 30% of total liver weight in a hamster model). Interestingly, all clones showed reduced virulence, which disappeared completely after 18 months of in vitro passage. Furthermore, the time to loss of virulence varied among the three clones (18, 12, and 6 months for ALA-1, ALA-5, and ALA-6, respectively). Whole-genome sequencing revealed a small number of single nucleotide polymorphisms at different stages in culture, none of which were shared among clones. Transcriptome analysis comparing gene expression between the highly virulent and avirulent states revealed several differentially expressed genes in each clone. However, there was minimal overlap in differentially expressed genes among the three clones, emphasizing the high complexity of virulence expression in E. histolytica.

conclusionsE. histolytica can transiently adapt their phenotypes according to culture conditions at the clone level. Further studies are needed to clarify the underlying mechanisms of this "protean" infectious disease.

Indexed as

Animal modelEntamoeba histolyticaTranscriptomeVirulenceWhole genome sequencing

Identifiers

PMID42298609
PMCPMC13505009

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.