In-house ELISA method to analyze anti-Trypanosoma cruzi IgG reactivity for differential diagnosis and evaluation of Chagas disease morbidity

Abstract

<jats:p>INTRODUCTION: The goal was to develop an in-house serological method with high specificity and sensitivity for diagnosis and monitoring of Chagas disease morbidity. METHODS: With this purpose, the reactivities of anti-T. cruzi IgG and subclasses were tested in successive serum dilutions of patients from Berilo municipality, Jequitinhonha Valley, Minas Gerais, Brazil. The performance of the in-house ELISA was also evaluated in samples from other relevant infectious diseases, including HIV, hepatitis C (HCV), syphilis (SYP), visceral leishmaniasis (VL), and American tegumentary leishmaniasis (ATL), and noninfected controls (NI). Further analysis was performed to evaluate the applicability of this in-house methodology for monitoring Chagas disease morbidity into three groups of patients: indeterminate (IND), cardiac (CARD), and digestive/mixed (DIG/Mix), based on their clinical status. RESULTS: The analysis of total IgG reactivity at serum dilution 1:40 was an excellent approach to Chagas disease diagnosis (100% sensitivity and specificity). The analysis of IgG subclasses showed cross-reactivity, mainly with NI, VL, and ATL, at all selected serum dilutions. Based on the data analysis, the IND group displayed higher IgG3 levels and the DIG/Mix group presented higher levels of total IgG as compared with the IND and CARD groups. CONCLUSIONS: These findings demonstrated that methodology presents promising applicability in the analysis of anti-T. cruzi IgG reactivity for the differential diagnosis and evaluation of Chagas disease morbidity.</jats:p>

Identification of phenotypic markers of B cells from patients with Chagas disease

“… showed that lower levels of IgG1 and IgG3 antibodies were found in chagasic patients with cardiac form the disease. The anti‐ T.cruzi antibodies present different reactivity in patients with distinct clinical forms . Our findings appoint that, although we did not showed differences of B cells markers between distinct clinical forms of the disease, the difference between control group and patients may indicate that distinct immune mechanisms involved with B cells may be important in the course of the disease.…”

Activity of the sesquiterpene lactone goyazensolide against Trypanosoma cruzi in vitro and in vivo

“…Enzyme-linked immunosorbent assay (ELISA) : Serum samples from all surviving animals were collected 90, 180 and 240 (d.p.t.). The ELISA reaction for detection of anti- T. cruzi IgG antibodies was performed and standardized in the Laboratory of Chagas Disease, UFOP (Voller et al ., 1976; Santos et al ., 2012). Sera samples were diluted 1:80 for analysis and peroxidase-labelled anti-mouse IgG conjugate diluted 1:2000 (SIGMA, St. Louis, USA) in buffered saline with 0.05% Tween 20 (PBS-Tween) were used.…”

Efficacy of Lychnopholide Polymeric Nanocapsules after Oral and Intravenous Administration in Murine Experimental Chagas Disease

“…Serum samples were collected via the orbital venous plexus at 90 and 180 dpt for detection of anti-T. cruzi IgG and were analyzed as described previously (33) and modified (34). A concentration of 4.5 g/ml of antigen, a serum dilution of 1:80, and peroxidase-conjugated anti-mouse IgG at a dilution of 1:2,000 were used.…”