Establishment of Larval Zebrafish as an Animal Model to Investigate <em>Trypanosoma cruzi</em> Motility <em>In Vivo</em>

Abstract

Chagas disease is a parasitic infection caused by Trypanosoma cruzi, whose motility is not only important for localization, but also for cellular binding and invasion. Current animal models for the study of T. cruzi allow limited observation of parasites in vivo, representing a challenge for understanding parasite behavior during the initial stages of infection in humans. This protozoan has a flagellar stage in both vector and mammalian hosts, but there are no studies describing its motility in vivo.The objective of this project was to establish a live vertebrate zebrafish model to evaluate T. cruzi motility in the vascular system. Transparent zebrafish larvae were injected with fluorescently labeled trypomastigotes and observed using light sheet fluorescence microscopy (LSFM), a noninvasive method to visualize live organisms with high optical resolution. The parasites could be visualized for extended periods of time due to this technique's relatively low risk of photodamage compared to confocal or epifluorescence microscopy. T. cruzi parasites were observed traveling in the circulatory system of live zebrafish in different-sized blood vessels and the yolk. They could also be seen attached to the yolk sac wall and to the atrioventricular valve despite the strong forces associated with heart contractions. LSFM of T. cruzi-inoculated zebrafish larvae is a valuable method that can be used to visualize circulating parasites and evaluate their tropism, migration patterns, and motility in the dynamic environment of the cardiovascular system of a live animal.

An Animal Model of Acute and Chronic Chagas Disease With the Reticulotropic Y Strain of Trypanosoma cruzi That Depicts the Multifunctionality and Dysfunctionality of T Cells

“…Indeed, experimental models of T. cruzi infection have been successfully used to propose or develop new strategies to combat ChD. To date, several animal models have been used to study many aspects of T. cruzi infection (13), including zebrafish (14), rabbits (15), dogs (16), rats (17), mice (18), and non-human primates (19). Given their small size and cost-effectiveness of laboratory maintenance, mice are one of the most promising animal models used to study this parasitic disease (18, 20).…”

T Cell Specificity: A Great Challenge in Chagas Disease

“…Despite the translational challenges of animal models in Chagas disease (24,25), they are still crucial for increasing the knowledge of the disease and the interaction between the host and the parasite (26)(27)(28)(29). Indeed, mouse models (wild type mice with H2 -mouse MHC-molecules or transgenic ones expressing human MHC) are broadly utilized under different strategies to evaluate the specificity of T cell response against T. cruzi infection (Figure 3).…”

Ambystoma mexicanum, a model organism in developmental biology and regeneration: a colombian experience

“…In Colombia, the main vertebrate models used in developmental biology and regeneration research, include chicken embryos (Carbonell et al, 2018;Meza Lasso et al, 2016), the common white mouse (Salazar and Arango, 2014) and zebrafish (Akle et al, 2017). Even though several amphibians are frequently used as vertebrate models to study development and regeneration, only a few studies report the use of amphibians such as Xenopus laevis) (Daudin, 1802) in electrophysiological studies (Chaves et al, 2003).…”