Phagocytosis of Acanthamoeba by macrophages and neutrophils and “kiss and run” evasion by Entamoeba histolytica
- 1Department of Microbiology and Immunology, University of Louisville
- 2Department of Medicine, University of Louisville School of Medicine
- 3Center for Predictive Medicine, University of Louisville
Abstract
Phagocytosis was discovered in the 19th century and is a cornerstone of innate immunity. Although amoebae species cause over 100 million cases of severe infections annually, one long-standing dogma remained unchallenged: that eukaryotic amoebae are too large to be phagocytosed. Here, we overturn this entrenched dogma and show that human macrophages and neutrophils efficiently phagocytose Acanthamoeba polyphaga and Vermamoeba vermiformis , in a phosphoinositide 3-kinase-dependent manner. In contrast, Entamoeba histolytica utilizes a “kiss and run” evasion strategy of phagocytosis. However, formalin-killed and UV-irradiated E. histolytica are efficiently phagocytosed. Macrophages respond to E. histolytica by formation of striking F-actin fibrillar projections, in contrast to the bona fide phagocytic cups that engulf killed E. histolytica , A. polyphaga , and V. vermiformis . Remarkably, neutrophils harboring phagocytosed amoebae are efferocytosed by macrophages. These findings redefine innate immunity to amoebae, the physical and biological limits of phagocytosis, and uncover divergent evolution among pathogenic amoebae to subvert phagocytosis.
IMPORTANCE: Eukaryotic amoebae have been presumed to be too large to be phagocytosed. We demonstrate that human macrophages and neutrophils can efficiently phagocytose diverse amoebae species, while Entamoeba histolytica evades phagocytosis, redefining innate immunity to amoebae and the physical limits of phagocytosis.
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BibTeX
@article{price2026phagocytosis,
title = {{Phagocytosis of Acanthamoeba by macrophages and neutrophils and “kiss and run” evasion by Entamoeba histolytica}},
author = {Christopher T. D. Price and Ryan S. Doster and Yousef Abu Kwaik},
journal = {mBio},
year = {2026},
month = nov,
doi = {10.1128/mbio.02294-26},
url = {https://journals.asm.org/doi/10.1128/mbio.02294-26},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Phagocytosis of Acanthamoeba by macrophages and neutrophils and “kiss and run” evasion by Entamoeba histolytica
AU - Christopher T. D. Price
AU - Ryan S. Doster
AU - Yousef Abu Kwaik
PY - 2026
DA - 2026/11/04
JO - mBio
DO - 10.1128/mbio.02294-26
UR - https://journals.asm.org/doi/10.1128/mbio.02294-26
AB - Phagocytosis was discovered in the 19th century and is a cornerstone of innate immunity. Although amoebae species cause over 100 million cases of severe infections annually, one long-standing dogma remained unchallenged: that eukaryotic amoebae are too large to be phagocytosed. Here, we overturn this entrenched dogma and show that human macrophages and neutrophils efficiently phagocytose Acanthamoeba polyphaga and Vermamoeba vermiformis , in a phosphoinositide 3-kinase-dependent manner. In contrast, Entamoeba histolytica utilizes a “kiss and run” evasion strategy of phagocytosis. However, formalin-killed and UV-irradiated E. histolytica are efficiently phagocytosed. Macrophages respond to E. histolytica by formation of striking F-actin fibrillar projections, in contrast to the bona fide phagocytic cups that engulf killed E. histolytica , A. polyphaga , and V. vermiformis . Remarkably, neutrophils harboring phagocytosed amoebae are efferocytosed by macrophages. These findings redefine innate immunity to amoebae, the physical and biological limits of phagocytosis, and uncover divergent evolution among pathogenic amoebae to subvert phagocytosis. IMPORTANCE: Eukaryotic amoebae have been presumed to be too large to be phagocytosed. We demonstrate that human macrophages and neutrophils can efficiently phagocytose diverse amoebae species, while Entamoeba histolytica evades phagocytosis, redefining innate immunity to amoebae and the physical limits of phagocytosis.
SN - 2150-7511
ER -