Spatial confinement of Trypanosoma brucei in microfluidic traps provides a new tool to study free swimming parasites

PLoS One. 2023 Dec 22;18(12):e0296257. doi: 10.1371/journal.pone.0296257. eCollection 2023.

Abstract

Trypanosoma brucei is the causative agent of African trypanosomiasis and is transmitted by the tsetse fly (Glossina spp.). All stages of this extracellular parasite possess a single flagellum that is attached to the cell body and confers a high degree of motility. While several stages are amenable to culture in vitro, longitudinal high-resolution imaging of free-swimming parasites has been challenging, mostly due to the rapid flagellar beating that constantly twists the cell body. Here, using microfabrication, we generated various microfluidic devices with traps of different geometrical properties. Investigation of trap topology allowed us to define the one most suitable for single T. brucei confinement within the field of view of an inverted microscope while allowing the parasite to remain motile. Chips populated with V-shaped traps allowed us to investigate various phenomena in cultured procyclic stage wild-type parasites, and to compare them with parasites whose motility was altered upon knockdown of a paraflagellar rod component. Among the properties that we investigated were trap invasion, parasite motility, and the visualization of organelles labelled with fluorescent dyes. We envisage that this tool we have named "Tryp-Chip" will be a useful tool for the scientific community, as it could allow high-throughput, high-temporal and high-spatial resolution imaging of free-swimming T. brucei parasites.

MeSH terms

  • Animals
  • Microfluidics
  • Parasites*
  • Swimming
  • Trypanosoma brucei brucei*
  • Trypanosomiasis, African*
  • Tsetse Flies* / parasitology

Grants and funding

MDN was funded by a Human Frontier Science Programme (HFSP) postdoctoral fellowship (LT000047/2019-L). Work in the Trypanosome Cell Biology Unit (PB Lab) is funded by an ANR grant (ANR-18-CE13-0014- 01) and by a French Government Investissement d’Avenir programme, Laboratoire d’Excellence “Integrative Biology of Emerging Infectious Diseases” (ANR-10-LABX-62-IBEID). We gratefully acknowledge the UTechS Photonic BioImaging (Imagopole), C2RT, Institut Pasteur, supported by the French National Research Agency (France BioImaging; ANR-10–INBS–04; Investments for the Future). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.