Identification of Immunodominant Antigens in Mexican Strains ofTrypanosoma cruzi

Abstract

Chagas disease represents an important public health problem. In Mexico most studies have been performed using Trypanosoma cruzi' antigens extracted from strains of other geographical origins. This work was aimed at developing a reactive antigen to perform serological diagnosis of Chagas' disease, using Mexican T. cruzi strains. We prepared antigenic extracts from epimastigotes, trypomastigotes and sphaeromastigotes of three Mexican strains. Parasites homogenate was obtained by lysis and sonication, solubilized proteins were analyzed by SDS-PAGE, Western-blot assays, and ELISA to determine the reactivity against sera from chagasic reference serum and chagasic and leishmaniasic patients and healthy donors. Western Blot profiles revealed, with the reference serum, eleven main components between 212 to 25 kDa; however, five bands corresponding to 74, 44, 31, 25 and 18 kDa antigens were recognized by the T. cruzi reactive sera from Mexican chagasic patients, which did not cross-react with Leishmania mexicana. Antigens from the Tequesquitengo strain yielded the best reactivity in the enzymatic immunoassay, thus enabling us to propose their use for serodiagnoses of Chagas' disease in Mexico.

Identification of a Western Blot Pattern for the Specific Diagnosis of Trypanosoma cruzi Infection in Human Sera

“…17,[26][27][28] The bands recognized by the sera of patients with Chagas disease and American CL, mucocutaneous leishmaniasis, and VL using homologous and heterologous antigens have been addressed previously, with different results. 17,20,[29][30][31][32] In our study, individual bands from the standard pattern were recognized by sera from patients with VL or CL, but the general pattern of reactivity of these sera was very different from the pattern of sera from Chagasic patients; in no case did it include more than four bands of those bands included in the standard pattern for Chagas disease.…”

“…12,[17][18][19][20][21][22][23] The main limitation of this technique is that it is difficult to perform interlaboratory comparisons, mainly due to the heterogeneity of the strains and antigenic preparations used. In addition, the size of the slab gels and the concentration of polyacrylamide used as well as the different molecular weight markers all introduce additional variations in band separation and the establishment of respective molecular weights.…”

North American import? Charting the origins of an enigmatic Trypanosoma cruzi domestic genotype

“…A panel of 72 TcI isolates and clones was assembled for analysis (Table 1) [11-16]. Of these, existing sequences and microsatellite data were available for 46 isolates [11,12].…”

High prevalence anti-Trypanosoma cruzi antibodies, among blood donors in the State of Puebla, a non-endemic area of Mexico

“…In Mexico, most studies have been performed using T. cruzi antigens extracted from strains originating from other geographical origins, mainly South America, that show different genotypes (Bucio et al 1999). …”