Re-examination of resistance of Toxoplasma gondii tachyzoites and bradyzoites to pepsin and trypsin digestion

Parasitology. 1998 Jan:116 ( Pt 1):43-50. doi: 10.1017/s0031182097001935.

Abstract

The effect of digestion in trypsin and acid pepsin on Toxoplasma gondii tachyzoites and bradyzoites was re-evaluated because of recent use of this method to distinguish tachyzoites from bradyzoites. Toxoplasma gondii tachyzoites survived better in 0.5% trypsin solution for 1 h than in 1.0% solution, and occasionally survived for 2 h in acid pepsin solution. Extracellular tachyzoites (> or = 1000) were also infectious orally to mice and cats. Bradyzoites survived equally in trypsin and acid pepsin solutions but the digestion of brain tissue in 0.5% trypsin solution was better than in acid pepsin solution. The resistance to digestion in acid pepsin solution is not a reliable method to distinguish tachyzoites from bradyzoites.

MeSH terms

  • Animals
  • Ascitic Fluid / parasitology
  • Brain / parasitology
  • Cats
  • Host-Parasite Interactions
  • Life Cycle Stages
  • Lung / parasitology
  • Mice
  • Pepsin A / metabolism
  • Pepsin A / pharmacology*
  • Species Specificity
  • Toxoplasma / drug effects
  • Toxoplasma / growth & development*
  • Toxoplasma / metabolism
  • Toxoplasma / pathogenicity
  • Toxoplasmosis, Animal / parasitology*
  • Trypsin / metabolism
  • Trypsin / pharmacology*

Substances

  • Trypsin
  • Pepsin A