The evaluation of a semiautomated computer method to determine the effects of DMSO on Giardia lamblia-intestinal cell interaction.

In this work, we describe a semiautomated computer method to evaluate the activity of a common drug solvent, dimethyl sulfoxide (DMSO), on in vitro Giardia lamblia-host cell interaction. To compare the number of intestinal cells (IEC-6) and the adhered trophozoites over a specific area in control and treated coculture, a computer routine was created. Using video-light microscopy and digital image-processing tools, the operator was able to count the number of epithelial cells or parasites when they were still lying on the slide surface and without the need to detach them from the substrate for counting with a hemocytometer or other counting devices. Using this strategy, we calculated the total cell number per area and verified the effects of different concentrations of DMSO on G. lamblia-intestinal cell interaction and on the IEC-6 culture. At concentrations of 0.2% and 1%, this solvent produced a fragmentation on the monolayer of epithelial cells. However, DMSO did not affect the attachment of G. lamblia. In the course of these experiments, we compared the semiautomated method to the manual counting method and found that the first one generated smaller standard deviations (SD) than the second.