Entamoeba histolytica is the causative agent of amoebiasis. Pathogenesis is associated with profound damage to human tissues. We previously showed that amoebae kill human cells through trogocytosis. Trogocytosis is likely to underlie tissue damage during infection, although the mechanism is still unknown. Trogocytosis is difficult to assay quantitatively, which makes it difficult to study. Here, we developed two new, complementary assays to measure trogocytosis by quantifying human cell death. One assay uses CellTiterGlo, a luminescent readout for ATP, as a proxy for cell death. We found that the CellTiterGlo could be used to detect death of human cells after co-incubation with amoebae, and that it was sensitive to inhibition of actin or the amoeba surface Gal/GalNAc lectin, two conditions that are known to inhibit amoebic trogocytosis. The other assay uses two fluorescent nuclear stains to directly differentiate live and dead human cells by microscopy, and is also sensitive to inhibition of amoebic trogocytosis through interference with actin. Both assays are simple and inexpensive, can be used with suspension and adherent human cell types, and are amenable to high-throughput approaches. These new assays are tools to improve understanding of trogocytosis and amoebiasis pathogenesis.

溶组织内阿米巴是阿米巴病的病原体。发病机制与对人体组织的严重损害有关。我们之前表明，变形虫通过吞噬作用杀死人类细胞。吞噬作用可能是感染期间组织损伤的基础，尽管其机制尚不清楚。Trogocytosis 难以定量测定，这使得研究变得困难。在这里，我们开发了两种新的、互补的检测方法，通过量化人类细胞死亡来测量吞噬作用。一种分析使用 CellTiterGlo（一种 ATP 的发光读数）作为细胞死亡的代理。我们发现 CellTiterGlo 可用于检测与变形虫共孵育后人类细胞的死亡，并且它对肌动蛋白或变形虫表面 Gal/GalNAc 凝集素的抑制敏感，这两种条件已知可抑制阿米巴细胞吞噬作用。另一种检测使用两种荧光核染色剂通过显微镜直接区分活的和死的人类细胞，并且对通过干扰肌动蛋白抑制阿米巴细胞吞噬作用也很敏感。这两种检测方法简单且价格低廉，可用于悬浮和贴壁人类细胞类型，并且适用于高通量方法。这些新的检测方法是提高对吞噬作用和阿米巴病发病机制理解的工具。