An advanced protocol for the purification of whipworm eggs from feces for use as therapeutic agents

Parasitol Int. 2019 Jun;70:41-45. doi: 10.1016/j.parint.2019.01.010. Epub 2019 Feb 1.


Recent studies have attempted to treat autoimmune diseases using Trichuris suis. whipworm) eggs. Large quantities of eggs can be obtained efficiently by collecting from the feces of the porcine hosts rather than by extracting from the female worm uterus. However, it is difficult to process large amounts of feces using the current methods. In the present study, we propose a method to collect the eggs from bulk feces more efficiently. Collecting the eggs using washing meshes (25 μm sieve) yields 65.7% (56.0-70.7) of eggs (median, min-max) from 100 g feces. Our method, which uses ethyl acetate and simulated gastric fluid, yielded 91.4% (91.4-94.0) of the eggs from 100 g feces into the separated aqueous solution. Egg collection using simulated gastric fluid (SGF) method was also 60 min faster than that using the sieve method. As the SGF used in the experiment is a strongly acidic reagent with a pH of 1-2, embryonation of the eggs was induced by the rapid pH change. As a result, 37.1% (8.0-77.8) of the eggs had embryonated two months after SGF stimulation. Using the developed method, we could process the feces quickly and efficiently. Furthermore, after purification, egg embryonation could be induced without any harmful reagent treatment. This method is expected to be helpful for further research using Trichuris suis eggs.

Keywords: Egg collection; Ethyl acetate; Simulated gastric fluid; Trichuris suis.

MeSH terms

  • Acetates
  • Acids / chemistry
  • Animals
  • Autoimmune Diseases / therapy
  • Feces / parasitology*
  • Female
  • Gastric Juice / chemistry
  • Hydrogen-Ion Concentration
  • Ovum / parasitology*
  • Parasite Egg Count / instrumentation
  • Parasite Egg Count / methods*
  • Swine
  • Trichuris / isolation & purification*


  • Acetates
  • Acids
  • ethyl acetate