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Chagas disease, caused by Trypanosoma cruzi parasite, is one of the most prevalent parasitic infections in Latin America and is responsible for millions of clinical cases. However, mainly because of [...]

Parasites are responsible for the most neglected tropical diseases, affecting over a billion people worldwide (WHO, 2015) and accounting for billions of cases a year and responsible for several millions of deaths. Research on extracellular vesicles (EVs) has increased in recent years and demonstrated that EVs shed by pathogenic parasites interact with host cells playing an important role in the parasite's survival, such as facilitation of infection, immunomodulation, parasite adaptation to the host environment and the transfer of drug resistance factors. Thus, EVs released by parasites mediate parasite‐parasite and parasite‐host intercellular communication. In addition, they are being explored as biomarkers of asymptomatic infections and disease prognosis after drug treatment. However, most current protocols used for the isolation, size determination, quantification and characterization of molecular cargo of EVs lack greater rigor, standardization, and adequate quality controls to certify the enrichment or purity of the ensuing bioproducts. We are now initiating major guidelines based on the evolution of collective knowledge in recent years. The main points covered in this position paper are methods for the isolation and molecular characterization of EVs obtained from parasite‐infected cell cultures, experimental animals, and patients. The guideline also includes a discussion of suggested protocols and functional assays in host cells [ABSTRACT FROM AUTHOR]

Chagas disease, caused by the protozoa parasite Trypanosoma cruzi, is a neglected tropical disease and a major public health problem affecting more than 6 million people worldwide. Many challenges remain in the quest to control Chagas disease: the diagnosis presents several limitations and the two available treatments cause several side effects, presenting limited efficacy during the chronic phase of the disease. In addition, there are no preventive vaccines or biomarkers of therapeutic response or disease outcome. Trypomastigote form and T. cruzi-infected cells release extracellular vesicles (EVs), which are involved in cell-to-cell communication and can modulate the host immune response. Importantly, EVs have been described as promising tools for the development of new therapeutic strategies, such as vaccines, and for the discovery of new biomarkers. Here, we review and discuss the role of EVs secreted during T. cruzi infection and their immunomodulatory properties. Finally, we briefly describe their potential for biomarker discovery and future perspectives as vaccine development tools for Chagas Disease. [ABSTRACT FROM AUTHOR]

The most severe clinical symptomatology of Chagas disease affects ~30% of those chronically infected with the Trypanosoma cruzi parasite. The pathogenic mechanisms that lead to life-threatening heart and gut tissue disruptions occur "silently" for a longtime in a majority of cases. As a result, despite there are several serological and molecular methods available to diagnose the infection in its acute and chronic stages, diagnosis is often achieved only after the onset of clinical symptoms in the chronic phase of the disease. Furthermore, although there are two drugs to treat it, the assessment of their performance is impractical with current parasite-derived diagnostics, and therapeutic efficacy cannot be acknowledged in a timely manner.In this chapter we present two procedures to measure host-derived molecules as surrogates of therapeutic response against chronic T. cruzi infection. Their outputs relate to the generation and activity of thrombin, a major component of the blood coagulation cascade. This is due to the fact that a hypercoagulability state has been described to occur in chronic Chagas disease patients and revert after treatment with benznidazole.