The virulence of  Toxoplasma gondii so far has been determined experimentally using mice. In an announcement the Swiss Foundation 3r reported an in vitro cell culture system which is suitable for  investigating the virulence of Toxoplasma gondii strains. In the study T. gondii strains of different virulence has been cultivated together with human epithelial cells from the intestine. The infectivity is correlated with the number and size of the observed phenomena in the cell layer. On the contrary   the degree of inhibition of the beta-defensin2 protein which is responsible for defence in the epithelial cells also decreases with the number of observed phenomena. These alterations could be used as  ndicators to determine the infectivity of Toxoplasma gondii in human intestinal cells without animal experiments.

More information: http://www.forschung3r.ch/de/projects/pr_107_07.html