Coccidian parasite can withstand a wide range of chemical and physical factors, contributing to their food- and water-borne transmission to humans worldwide. Eimeria acervulina has been proposed as a non-human pathogenic alternative of Toxoplasma gondii to assess food and water decontamination, however it is not known whether the two parasites exposed to chemical and thermal treatments parallel in terms of oocyst structure and infectivity. Using bioassays and lectin-based assays combined with flow cytometry and fluorescence microscopy analyses, this study shows that E. acervulina and T. gondii oocysts display similar response to heating and/or freezing and bleach or NaOH treatments, as in maintaining infectivity, with E. acervulina oocysts retaining their size and structure better than T. gondii. Collectively, these results suggest that E. acervulina is a reliable model for studying the response of T. gondii oocysts to certain chemical and physical agents.

https://doi.org/10.1016/j.exppara.2025.109049

Understanding the transport and retention of Toxoplasma gondii oocysts through soils and into ground and surface water is essential for determining the risk this parasite poses to water resources and human health worldwide. We studied here how various naturally occurring groundwater solutions containing different types of organic compounds (fulvic and humic acids) and electrolytes (NaCl, MgCl₂, CaCl₂) at different concentrations can affect the transport and retention of oocysts in engineered-saturated silica sand columns subjected to continuous flow to simulate the movement of groundwater through an aquifer. Breakthrough curve results from the qPCR analysis were then compared to non-reactive tracer tests to determine parameters that govern the transport of oocysts in saturated porous media. Though breakthrough of oocysts was observed in all tested solutions, higher ionic strength and ion valency resulted in greater oocyst retention. When both organic matter and electrolyte solutions were added to the systems, the electrolyte solutions displayed a far greater influence on parasite retention when compared to the influence of the organic matter alone. Collectively, this study demonstrates the pivotal role of soil groundwater solution chemistry in both the transport and retention of this important zoonotic parasite

https://doi.org/10.1371/journal.pone.0331812

We present a detailed protocol for conducting high-content microscopy assays of immune cells interacting with antigen surfaces and antigen-presenting cells. The principle of the method is illustrated by redirecting NK cells on HER2 antigens using original bispecific antibodies. We provide a complete analysis pipeline using our open-source, home-made software, Celldetective.

🔗 Article