In Vivo Bioluminescence Imaging to Assess Compound Efficacy Against Trypanosoma brucei.

Traditional animal models for human African trypanosomiasis rely on detecting Trypanosoma brucei brucei parasitemia in the blood. Testing the efficacy of new compounds in these models is cumbersome because it may take several months after treatment before surviving parasites become detectable in the blood. To expedite compound screening, we have used a Trypanosoma brucei brucei GVR35 strain expressing red-shifted firefly luciferase to monitor parasite distribution in infected mice through noninvasive whole-body bioluminescence imaging. This protocol describes the infection and in vivo bioluminescence imaging of mice to assess compound efficacy against T. brucei during the two characteristic stages of disease, the hemolymphatic phase (stage 1) and the encephalitic or central nervous system phase (stage 2).

Impedance-Based Microfluidic Assay for Automated Antischistosomal Drug Screening.

Schistosomiasis is a neglected tropical disease, caused by parasitic worms, which affects almost 200 million people worldwide. For over 40 years, chemotherapeutic treatment has relied on the administration of praziquantel, an efficacious drug against schistosomiasis. However, concerns about developing drug resistance require the discovery of novel drug compounds. Currently, the drug-screening process is mostly based on the visual evaluation of drug effects on worm larvae in vitro by a trained operator. This manual process is extremely labor-intensive, has limited throughput, and may be affected by subjectivity of the operator evaluation. In this paper, we introduce a microfluidic platform with integrated electrodes for the automated detection of worm larvae viability using an impedance-based approach. The microfluidic analysis unit consists of two sets of electrodes and a channel of variable geometry to enable counting and size detection of single parasite larvae and the collective evaluation of the motility of the larvae as an unbiased estimator for their viability. The current platform also allows for multiplexing of the analysis units resulting in increased throughput. We used our platform to record size and motility variations of Schistosoma mansoni larvae exposed to different concentrations of mefloquine, a drug with established in vitro antischistosomal properties. The developed platform demonstrates the potential of integrated microfluidic platforms for high-throughput antischistosomal drug screening.