Guided STED nanoscopy enables super-resolution imaging of blood stage malaria parasites

Sci Rep. 2019 Mar 18;9(1):4674. doi: 10.1038/s41598-019-40718-z.

Abstract

Malaria remains a major burden world-wide, but the disease-causing parasites from the genus Plasmodium are difficult to study in vitro. Owing to the small size of the parasites, subcellular imaging poses a major challenge and the use of super-resolution techniques has been hindered by the parasites' sensitivity to light. This is particularly apparent during the blood-stage of the Plasmodium life cycle, which presents an important target for drug research. The iron-rich food vacuole of the parasite undergoes disintegration when illuminated with high-power lasers such as those required for high resolution in Stimulated Emission Depletion (STED) microscopy. This causes major damage to the sample precluding the use of this super-resolution technique. Here we present guided STED, a novel adaptive illumination (AI) STED approach, which takes advantage of the highly-reflective nature of the iron deposit in the cell to identify the most light-sensitive parts of the sample. Specifically in these parts, the high-power STED laser is deactivated automatically to prevent local damage. Guided STED nanoscopy finally allows super-resolution imaging of the whole Plasmodium life cycle, enabling multicolour imaging of blood-stage malaria parasites with resolutions down to 35 nm without sample destruction.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blood / parasitology*
  • Diagnostic Imaging / methods*
  • Humans
  • Life Cycle Stages
  • Malaria / diagnosis*
  • Microscopy, Fluorescence
  • Nanostructures
  • Plasmodium falciparum / physiology*
  • Plasmodium falciparum / ultrastructure
  • Vacuoles