ABSTRACT
Here, we report an inhibitory effect of a sesquiterpene lactone dehydroleucodine (DhL) on the growth of Trypanosoma cruzi in culture. At concentrations of the drug between 5 and 10 microg/ml in the medium,the parasites remained alive for at least 4 days. Higher concentrations of DhL were lethal for the parasites within a few hours. The effect of DhL is irreversible. Morphological changes induced by DhL were also observed in the parasites. The effect of DhL was blocked by the presence of reducing substrates such as glutathione or dithiothreitol, but these agents were not able to reverse the effect of DhL if added 2 days after the start of drug exposure.
Subject(s)
Lactones/pharmacology , Sesquiterpenes/pharmacology , Trypanosoma cruzi/drug effects , Animals , Artemisia/chemistry , Culture Media , Lactones/chemistry , Lactones/isolation & purification , Microscopy, Electron , Plants, Medicinal , Sesquiterpenes/chemistry , Sesquiterpenes/isolation & purification , Trypanosoma cruzi/growth & development , Trypanosoma cruzi/ultrastructureABSTRACT
Serum of chagasic patients with a high title of specific antibodies against T. cruzi antigens, binds epitopes in the midgut and hindgut of the insect vector Triatoma infestans free of parasites. These antigens were recognized at ultrastructural level by immunocytochemistry with serum of chagasic patients as first antibody and protein "A"-gold as marker. Controls with normal human serum were negative. The positive reaction occurs principally in the apical epithelial portion (microvilli and peritrophic membrane) of the midgut and in the cuticular layer and adjacent cytoplasm of the hindgut. In vectors infected with trypanosomes, the antigen-antibody reaction occurs similarly in the epithelium and also in the trypanosomes present in the lumen. These results suggest that there are antigenic factors in the vector gut that are incorporated by the parasite and are recognized by the immunitary system of the human patient with production of specific antibodies.
Subject(s)
Antibodies, Protozoan/immunology , Chagas Disease/immunology , Triatoma/immunology , Trypanosoma cruzi/immunology , Animals , Antibodies/blood , Antibodies/immunology , Antibodies, Protozoan/blood , Antibody Specificity , Chagas Disease/blood , Epithelium/immunology , Humans , Immunohistochemistry , Intestinal Mucosa/immunology , Microscopy, ImmunoelectronABSTRACT
Serum of chagasic patients with a high title of specific antibodies against T. cruzi antigens, binds epitopes in the midgut and hindgut of the insect vector Triatoma infestans free of parasites. These antigens were recognized at ultrastructural level by immunocytochemistry with serum of chagasic patients as first antibody and protein [quot ]A[quot ]-gold as marker. Controls with normal human serum were negative. The positive reaction occurs principally in the apical epithelial portion (microvilli and peritrophic membrane) of the midgut and in the cuticular layer and adjacent cytoplasm of the hindgut. In vectors infected with trypanosomes, the antigen-antibody reaction occurs similarly in the epithelium and also in the trypanosomes present in the lumen. These results suggest that there are antigenic factors in the vector gut that are incorporated by the parasite and are recognized by the immunitary system of the human patient with production of specific antibodies.
ABSTRACT
Serum of chagasic patients with a high title of specific antibodies against T. cruzi antigens, binds epitopes in the midgut and hindgut of the insect vector Triatoma infestans free of parasites. These antigens were recognized at ultrastructural level by immunocytochemistry with serum of chagasic patients as first antibody and protein [quot ]A[quot ]-gold as marker. Controls with normal human serum were negative. The positive reaction occurs principally in the apical epithelial portion (microvilli and peritrophic membrane) of the midgut and in the cuticular layer and adjacent cytoplasm of the hindgut. In vectors infected with trypanosomes, the antigen-antibody reaction occurs similarly in the epithelium and also in the trypanosomes present in the lumen. These results suggest that there are antigenic factors in the vector gut that are incorporated by the parasite and are recognized by the immunitary system of the human patient with production of specific antibodies.
ABSTRACT
Serum of chagasic patients with a high title of specific antibodies against T. cruzi antigens, binds epitopes in the midgut and hindgut of the insect vector Triatoma infestans free of parasites. These antigens were recognized at ultrastructural level by immunocytochemistry with serum of chagasic patients as first antibody and protein [quot ]A[quot ]-gold as marker. Controls with normal human serum were negative. The positive reaction occurs principally in the apical epithelial portion (microvilli and peritrophic membrane) of the midgut and in the cuticular layer and adjacent cytoplasm of the hindgut. In vectors infected with trypanosomes, the antigen-antibody reaction occurs similarly in the epithelium and also in the trypanosomes present in the lumen. These results suggest that there are antigenic factors in the vector gut that are incorporated by the parasite and are recognized by the immunitary system of the human patient with production of specific antibodies.
ABSTRACT
Serum of chagasic patients with a high title of specific antibodies against T. cruzi antigens, binds epitopes in the midgut and hindgut of the insect vector Triatoma infestans free of parasites. These antigens were recognized at ultrastructural level by immunocytochemistry with serum of chagasic patients as first antibody and protein [quot ]A[quot ]-gold as marker. Controls with normal human serum were negative. The positive reaction occurs principally in the apical epithelial portion (microvilli and peritrophic membrane) of the midgut and in the cuticular layer and adjacent cytoplasm of the hindgut. In vectors infected with trypanosomes, the antigen-antibody reaction occurs similarly in the epithelium and also in the trypanosomes present in the lumen. These results suggest that there are antigenic factors in the vector gut that are incorporated by the parasite and are recognized by the immunitary system of the human patient with production of specific antibodies.