Giardia lamblia: Distribuição de Microtúbulos no citoesqueleto de trofozoítos e cistos utilizando taxóide fluorescente

Abstract

G. lamblia is a protozoan parasite of the small intestine and the etiologic agent ofgiardiosis, which presents a complex cytoskeleton composed of microtubules. Inthis study, the microtubule cytoskeleton was labeled in trophozoites and cysts ofG. lamblia, using a fluorescent taxoid (FLUTAX-2), a derivative of Taxol, whichbinds to ??-tubulin dimer polymerized. In addition, the effect of metronidazole onthe cytoskeleton of the parasite was also evaluated. FLUTAX-2 was able to labelthe microtubules of trophozoites and cysts, allowing the observation of cytoskeletalstructures, such as flagella, funis, adhesive disk, and median body. Moreover,FLUTAX-2 labeled the trophozoites from several different cultivation times,revealing the 48 hours as the best incubation period. The incubation of parasites inpresence of metronidazole did not show significant alteration on the microtubulelabeling by FLUTAX-2. We have shown the FLUTAX-2 labeling in other protozoa,Trichomonas vaginalis, T. gallinae and Tritrichomonas foetus, and this is the firstreport revealing the binding profile in G. lamblia. Our results contribute to theknowledge of biological and morphological features of this intestinal pathogen. Furthermore, our data showed no modification of microtubule profile labeling inpresence of metronidazole. Finally, a new perspective for giardiosis diagnosticis suggested, since trophozoites and cysts of G. lamblia were labeled with FLUTAX-2.